VBA macro for printing is having performance issues - vba

Question

I have a subroutine in an Access db that takes the active Word document and sends the first of every n pages to one printer, and the rest to another. The macro works, but it runs progressively slower with each loop. So far it's taken 1h 40m to print 300 pages (100 recipients, 3 pages each).
Anyone out there know how I can speed things up?
Here's an example of the typical params being passed in: cmdPrintStart(3, 1, 247, "\Main", "\Letterhead")
Public Sub cmdPrintStart(tbPageCount As Long, tbStart As Long, tbEnd As Long, Printer1 As String, Printer2 As String)
On Error GoTo Exit_Handler
Dim wApp As Word.Application
SetWordApp wApp 'This sub sets wApp to an instance of Word, or creates one if none is found.
With wApp.ActiveDocument
Dim DefaultPrinter As String, i As Long
DefaultPrinter = ActivePrinter
For i = tbStart To tbEnd
Debug.Print = "Printing recipient " & i & " of " & (tbStart - tbEnd + 1) & "..."
'Switch active printer and print first page of section
ActivePrinter = Printer1
.PrintOut Range:=wdPrintFromTo, From:="p1s" & i, To:="p1s" & i
'Switch active printer and print the rest of the section
ActivePrinter = Printer2
.PrintOut Range:=wdPrintFromTo, From:="p2s" & i, To:="p" & tbPageCount & "s" & i
Next i
End With
ActivePrinter = DefaultPrinter
Exit_Handler:
If Err Then
MsgBox "Unexpected error #" & Str(Err.Number) & " occurred: " & Err.Description, vbCritical, "Well shoot."
Debug.Print = "Printed up to recipient " & i & " before encountering an error."
Else
Debug.Print = "All done! Printed recipients " & tbStart & " to " & tbEnd & "."
End If
End Sub
Further info:
The purpose is to send page 1 of each section in a mail merge document to a tray with letterhead paper, and the other pages to normal paper, printed in collated order. Surprisingly, there doesn't seem to be anything in Word that allows you to do this.
The active document is a post-merged document. If it will improve performance, I can try writing a sub to print from the mail merge template with the connected data source instead.
Thanks in advance for your help.

Answer 1

I'm just taking a wild guess here: does each loop open a new instance of Word in memory, with the result that after many loop executions you're running out of memory? Maybe try dereferencing your Word object at the end of each loop, something like
wApp.Close
Set wApp = nothing
I don't know that it will help but it surely can't hurt.