Private Sub Form_Open(Cancel As Integer) 
Set wrkCur = DAO.DBEngine.Workspaces( 0 ) 
wrkCur.BeginTrans 
fTr = True 
End Sub 
.... 
If fTr = True Then 
wrkCur.CommitTrans 
fTr = False 
End If 

Private WithEvents frmChild As Form

    Dim W As DAO.Workspace
    Dim RecSet1 As DAO.Recordset
    Dim RecSet2 As DAO.Recordset
    Dim b As Boolean

Private Sub Form_Load()

    Set W = DBEngine.Workspaces( 0 )
    Set frmChild = Me!calc.Form
    Set RecSet1 = CurrentDb.OpenRecordset( "..." )
    Set RecSet2 = CurrentDb.OpenRecordset( "..." )
    
    Set Me.Recordset = RecSet1
    Set Me!calc.Form.Recordset = RecSet2
    b = False
    
End Sub

Private Sub Form_Dirty(Cancel As Integer)

If b = False Then
    W.BeginTrans
    b = True
End If

End Sub

Private Sub frmChild_Dirty(Cancel As Integer)

If b = False Then
    W.BeginTrans
    b = True
End If

End Sub