Working on the MG Transmission

Tony Wells

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Drill blanks, or check into PeeDee wires. Good job on the fitup.

Everyone have the formula(s) for thread wires? Unified, and Acme/Stub Acme? 55 deg?
 
'Tis true, that. It is making a certain assumption, but is generally safe for repair work. I'm more used to meeting drawing requirements and passing Incoming QC. Tough not having gages.
 
Tables are fine, but don't cover all the weird threads that are possible, or Acme, Stub Acme, or other specials that engineers dream up.

And a side note, since the MoW method is intended to measure right at the pitch line, the standard sets like the PeeDee sets don't actually have the "right" size for many of the non UN series threads.
 
Is it possible the fastener threads in your transmission are 55 degree Withworth?

I know a guy restoring a series 1.5 e-Type, and all the fasteners in the car are in SAE UNF. Thankfully still readily available.
 
My boss and his kids have a few 50s MGs(1952 MG TD, 1957 Magnetta). The transmissions use British Standard Fine thread and Whitworth threaded fasteners.
 
Of course .whitworth threads are 55 degrees, with a slightly rounded top.
MG threads are a combination of whitworth heads and old French
Standard Metric. Don't ask, and I won't give you along explanation.

BLJHB.
 
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