<?xml version="1.0" encoding="utf-8"?>
<!--XBRL document created with Toppan Merrill Bridge  11.4.0.1 -->
<!--Based on XBRL 2.1-->
<!--Created on: 8/3/2026 8:51:45 PM-->
<!--Modified on: 8/3/2026 8:51:45 PM-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrli="http://www.xbrl.org/2003/instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#StatementCondensedConsolidatedBalanceSheets" roleURI="http://www.mecinc.com/role/StatementCondensedConsolidatedBalanceSheets" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" roleURI="http://www.mecinc.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#StatementCondensedConsolidatedStatementsOfCashFlows" roleURI="http://www.mecinc.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureAcquisitionAssetsAcquiredLiabilitiesAssumedDetails" roleURI="http://www.mecinc.com/role/DisclosureAcquisitionAssetsAcquiredLiabilitiesAssumedDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureSelectBalanceSheetDataScheduleOfInventoriesDetails" roleURI="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfInventoriesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureSelectBalanceSheetDataScheduleOfPropertyPlantAndEquipmentDetails" roleURI="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfPropertyPlantAndEquipmentDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureSelectBalanceSheetDataScheduleOfListingOfIntangibleAssetsDetails" roleURI="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfListingOfIntangibleAssetsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureLeasesComponentsOfLeaseExpenseDetails" roleURI="http://www.mecinc.com/role/DisclosureLeasesComponentsOfLeaseExpenseDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260630.xsd#DisclosureEarningsPerShareDetails" roleURI="http://www.mecinc.com/role/DisclosureEarningsPerShareDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item" />
  <calculationLink xlink:role="http://www.mecinc.com/role/StatementCondensedConsolidatedBalanceSheets" xlink:type="extended" xlink:title="995200100 - Statement - Condensed Consolidated Balance Sheets" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent_639213871039918759" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_AssetsCurrent_639213871039918759" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_639213871039918759" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639213871039918759" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_639213871039918759" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="us-gaap_ReceivablesNetCurrent_639213871039918759" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639213871039918759" xlink:to="us-gaap_ReceivablesNetCurrent_639213871039918759" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet_639213871039918759" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639213871039918759" xlink:to="us-gaap_InventoryNet_639213871039918759" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_ToolingInProgressNet" xlink:label="mec_ToolingInProgressNet_639213871039918759" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639213871039918759" xlink:to="mec_ToolingInProgressNet_639213871039918759" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639213871039918759" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639213871039924377" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_639213871039924377" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Goodwill_639213871039924377" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup" xlink:label="us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup_639213871039924377" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_IntangibleAssetsNetExcludingGoodwill_639213871039924377" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_639213871039924377" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_639213871039924377" order="6" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent_639213871039929776" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Assets" xlink:to="us-gaap_OtherAssetsNoncurrent_639213871039929776" order="7" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities_639213871039929997" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_Liabilities_639213871039929997" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent_639213871039929997" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_LiabilitiesCurrent_639213871039929997" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent_639213871039929997" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639213871039929997" xlink:to="us-gaap_AccountsPayableCurrent_639213871039929997" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_639213871039929997" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639213871039929997" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent_639213871039929997" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_AccruedSalariesWagesAndPayrollTaxesCurrent" xlink:label="mec_AccruedSalariesWagesAndPayrollTaxesCurrent_639213871039935613" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639213871039929997" xlink:to="mec_AccruedSalariesWagesAndPayrollTaxesCurrent_639213871039935613" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedBonusesCurrent" xlink:label="us-gaap_AccruedBonusesCurrent_639213871039935613" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639213871039929997" xlink:to="us-gaap_AccruedBonusesCurrent_639213871039935613" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="us-gaap_OtherLiabilitiesCurrent_639213871039935613" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639213871039929997" xlink:to="us-gaap_OtherLiabilitiesCurrent_639213871039935613" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermLineOfCredit" xlink:label="us-gaap_LongTermLineOfCredit_639213871040016027" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_LongTermLineOfCredit_639213871040016027" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_639213871040016027" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent_639213871040016027" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent" xlink:label="us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent_639213871040016027" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_DeferredCompensationCashbasedArrangementsLiabilityClassifiedNoncurrent_639213871040016027" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredIncomeTaxLiabilitiesNet" xlink:label="us-gaap_DeferredIncomeTaxLiabilitiesNet_639213871040016027" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_DeferredIncomeTaxLiabilitiesNet_639213871040016027" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639213871039929997" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_639213871040026719" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_StockholdersEquity_639213871040026719" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639213871040026719" xlink:to="us-gaap_CommonStockValue_639213871040026719" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalCommonStock" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639213871040026719" xlink:to="us-gaap_AdditionalPaidInCapitalCommonStock_639213871040026719" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639213871040026719" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_639213871040026719" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TreasuryStockCommonValue" xlink:label="us-gaap_TreasuryStockCommonValue_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639213871040026719" xlink:to="us-gaap_TreasuryStockCommonValue_639213871040026719" order="4" use="optional" weight="-1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="extended" xlink:title="995200200 - Statement - Condensed Consolidated Statements of Comprehensive Income (Loss)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639213871040026719" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639213871040026719" xlink:to="us-gaap_OperatingIncomeLoss_639213871040026719" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639213871040026719" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue" xlink:label="us-gaap_CostOfRevenue_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="us-gaap_CostOfRevenue_639213871040026719" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="us-gaap_AmortizationOfIntangibleAssets_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="us-gaap_AmortizationOfIntangibleAssets_639213871040026719" order="3" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense" xlink:label="us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_639213871040026719" order="4" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherSellingGeneralAndAdministrativeExpense" xlink:label="us-gaap_OtherSellingGeneralAndAdministrativeExpense_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="us-gaap_OtherSellingGeneralAndAdministrativeExpense_639213871040026719" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_ImpairmentOfLongLivedAssets" xlink:label="mec_ImpairmentOfLongLivedAssets_639213871040026719" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639213871040026719" xlink:to="mec_ImpairmentOfLongLivedAssets_639213871040026719" order="6" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseNonoperating" xlink:label="us-gaap_InterestExpenseNonoperating_639213871040042131" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639213871040026719" xlink:to="us-gaap_InterestExpenseNonoperating_639213871040042131" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639213871040026719" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_639213871040042360" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_IncomeTaxExpenseBenefit_639213871040042360" order="2" use="optional" weight="-1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/StatementCondensedConsolidatedStatementsOfCashFlows" xlink:type="extended" xlink:title="995200300 - Statement - Condensed Consolidated Statements of Cash Flows" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProfitLoss" xlink:label="us-gaap_ProfitLoss_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_ProfitLoss_639213871040042360" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation" xlink:label="us-gaap_Depreciation_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_Depreciation_639213871040042360" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentForAmortization" xlink:label="us-gaap_AdjustmentForAmortization_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_AdjustmentForAmortization_639213871040042360" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_ShareBasedCompensation_639213871040042360" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_ProvisionForDoubtfulAccounts_639213871040042360" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_InventoryExcessAndObsolescenceReserve" xlink:label="mec_InventoryExcessAndObsolescenceReserve_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_InventoryExcessAndObsolescenceReserve_639213871040042360" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_GainLossOnSaleOfPropertyPlantEquipment_639213871040042360" order="7" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_ImpairmentOfLongLivedAssets" xlink:label="mec_ImpairmentOfLongLivedAssets_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_ImpairmentOfLongLivedAssets_639213871040042360" order="8" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_DeferredCompensationNonCash" xlink:label="mec_DeferredCompensationNonCash_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_DeferredCompensationNonCash_639213871040042360" order="9" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_639213871040042360" order="10" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNoncashIncomeExpense" xlink:label="us-gaap_OtherNoncashIncomeExpense_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_OtherNoncashIncomeExpense_639213871040042360" order="11" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_NonCashLeaseExpense" xlink:label="mec_NonCashLeaseExpense_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_NonCashLeaseExpense_639213871040042360" order="12" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable_639213871040042360" order="13" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="us-gaap_IncreaseDecreaseInInventories_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInInventories_639213871040042360" order="14" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_IncreaseDecreaseInToolingInProcess" xlink:label="mec_IncreaseDecreaseInToolingInProcess_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_IncreaseDecreaseInToolingInProcess_639213871040042360" order="15" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639213871040042360" order="16" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_IncreaseDecreaseInDeferredTaxes" xlink:label="mec_IncreaseDecreaseInDeferredTaxes_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="mec_IncreaseDecreaseInDeferredTaxes_639213871040042360" order="17" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_639213871040042360" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayable_639213871040042360" order="18" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_639213871040062761" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_639213871040062761" order="19" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilities_639213871040062761" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639213871040042360" xlink:to="us-gaap_IncreaseDecreaseInAccruedLiabilities_639213871040062761" order="20" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_639213871040062761" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_639213871040062761" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_639213871040062761" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639213871040062761" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_639213871040062761" order="1" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_639213871040062761" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639213871040062761" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_639213871040062761" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromLinesOfCredit" xlink:label="us-gaap_ProceedsFromLinesOfCredit_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_ProceedsFromLinesOfCredit_639213871040068375" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfLinesOfCredit" xlink:label="us-gaap_RepaymentsOfLinesOfCredit_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_RepaymentsOfLinesOfCredit_639213871040068375" order="2" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="us-gaap_ProceedsFromIssuanceOfCommonStock_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_ProceedsFromIssuanceOfCommonStock_639213871040068375" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfFinancingCosts" xlink:label="us-gaap_PaymentsOfFinancingCosts_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_PaymentsOfFinancingCosts_639213871040068375" order="4" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_639213871040068375" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_PaymentsForRepurchaseOfCommonStock_639213871040068375" order="6" use="optional" weight="-1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeasePrincipalPayments" xlink:label="us-gaap_FinanceLeasePrincipalPayments_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639213871040068375" xlink:to="us-gaap_FinanceLeasePrincipalPayments_639213871040068375" order="7" use="optional" weight="-1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureAcquisitionAssetsAcquiredLiabilitiesAssumedDetails" xlink:type="extended" xlink:title="99940202 - Disclosure - Acquisition - Assets acquired, liabilities assumed (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_639213871040068375" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory_639213871040068375" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_639213871040068375" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_639213871040068375" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredOperatingLeaseRightOfUseAsset" xlink:label="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredOperatingLeaseRightOfUseAsset_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredOperatingLeaseRightOfUseAsset_639213871040068375" order="6" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibles_639213871040068375" order="7" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets_639213871040068375" order="8" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets_639213871040068375" xlink:to="us-gaap_Goodwill_639213871040068375" order="9" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesCurrent" xlink:label="mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesCurrent_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesCurrent_639213871040068375" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesWagesAndPayrollTaxes" xlink:label="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesWagesAndPayrollTaxes_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesWagesAndPayrollTaxes_639213871040068375" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesBonusesAndDeferredCompensation" xlink:label="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesBonusesAndDeferredCompensation_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="mec_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedSalariesBonusesAndDeferredCompensation_639213871040068375" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther_639213871040068375" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesNonCurrent" xlink:label="mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesNonCurrent_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="mec_BusinessCombinationRecognizedLiabilityAssumedLeaseLiabilitiesNonCurrent_639213871040068375" order="6" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities_639213871040068375" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther_639213871040068375" order="7" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfInventoriesDetails" xlink:type="extended" xlink:title="99940301 - Disclosure - Select balance sheet data - Schedule of Inventories (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="us-gaap_InventoryFinishedGoodsNetOfReserves_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryFinishedGoodsNetOfReserves_639213871040068375" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryRawMaterialsNetOfReserves" xlink:label="us-gaap_InventoryRawMaterialsNetOfReserves_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryRawMaterialsNetOfReserves_639213871040068375" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryWorkInProcessNetOfReserves" xlink:label="us-gaap_InventoryWorkInProcessNetOfReserves_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryWorkInProcessNetOfReserves_639213871040068375" order="3" use="optional" weight="1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfPropertyPlantAndEquipmentDetails" xlink:type="extended" xlink:title="99940302 - Disclosure - Select balance sheet data - Schedule of Property, Plant and Equipment (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="us-gaap_PropertyPlantAndEquipmentGross_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_PropertyPlantAndEquipmentGross_639213871040068375" order="1" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_639213871040068375" order="2" use="optional" weight="-1" priority="2" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureSelectBalanceSheetDataScheduleOfListingOfIntangibleAssetsDetails" xlink:type="extended" xlink:title="99940305 - Disclosure - Select balance sheet data - Schedule of Listing of Intangible Assets (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet_1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet_1" xlink:to="us-gaap_FiniteLivedIntangibleAssetsGross_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet_1" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_639213871040068375" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsGrossExcludingGoodwill_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IntangibleAssetsNetExcludingGoodwill_1" xlink:to="us-gaap_IntangibleAssetsGrossExcludingGoodwill_639213871040068375" order="1" use="optional" weight="1" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IntangibleAssetsNetExcludingGoodwill_1" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_639213871040068375" order="2" use="optional" weight="-1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureLeasesComponentsOfLeaseExpenseDetails" xlink:type="extended" xlink:title="99940501 - Disclosure - Leases - Components of lease expense (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LeaseCost" xlink:label="us-gaap_LeaseCost_1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_VariableLeaseCost" xlink:label="us-gaap_VariableLeaseCost_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LeaseCost_1" xlink:to="us-gaap_VariableLeaseCost_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubleaseIncome" xlink:label="us-gaap_SubleaseIncome_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LeaseCost_1" xlink:to="us-gaap_SubleaseIncome_639213871040068375" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermLeaseCost" xlink:label="us-gaap_ShortTermLeaseCost_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LeaseCost_1" xlink:to="us-gaap_ShortTermLeaseCost_639213871040068375" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseCost" xlink:label="us-gaap_OperatingLeaseCost_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LeaseCost_1" xlink:to="us-gaap_OperatingLeaseCost_639213871040068375" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260630.xsd#mec_FinanceLeaseCost" xlink:label="mec_FinanceLeaseCost_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LeaseCost_1" xlink:to="mec_FinanceLeaseCost_639213871040068375" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseInterestExpense" xlink:label="us-gaap_FinanceLeaseInterestExpense_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="mec_FinanceLeaseCost_639213871040068375" xlink:to="us-gaap_FinanceLeaseInterestExpense_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseRightOfUseAssetAmortization" xlink:label="us-gaap_FinanceLeaseRightOfUseAssetAmortization_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="mec_FinanceLeaseCost_639213871040068375" xlink:to="us-gaap_FinanceLeaseRightOfUseAssetAmortization_639213871040068375" order="2" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.mecinc.com/role/DisclosureEarningsPerShareDetails" xlink:type="extended" xlink:title="99941401 - Disclosure - Earnings Per Share (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_639213871040068375" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_639213871040068375" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_639213871040068375" order="2" use="optional" weight="1" />
  </calculationLink>
</link:linkbase>
