Winshield, Stanchion to frame assembly.

[Arrow]

Contradiction between TRF and Moss and what I have. I have an appointment tomorrow to assemble my windshield (new glass from Moss). I have had the frame components re-chromed. There are three screws that hold the Stanchion, Tenon Plate and frame together. Moss calls for 4 each (2 per side) of #323-085 short screws (7/8 inch) and 2 each (1 per side) of #323-305 long screws (1 inch). The Roadster Factory calls for 2 each (1 per side) of #561206 shorter screw (I bought TRF screws and they are 7/8 inches) and 4 each #552662 longer screws (again I bought these and they are indeed 1 inch long). Obvioously this info is contradictory.

All these screws are 10-32.

To confuse matters these screws go into a small metal strip inside the frame, The top and bottom screws on mine are threaded 10-32 BUT the middle screw is threaded 6-32.

Here are my questions?

1-starting from the top of the frame working down what is the correct length of screw? Top hole, middle hole, bottom hole.

2-can anyone address why both vendors supply 10-32 for all holes and my frame clearly takes a 10-32 in the top, 6-32 in the middle and 10-32 in the bottom hole. I will try to attach a photo of the two metal strips that fit inside the frame and hopefully you can tell the screw holes are different sizes.

 

[CJD]

On both my cars they were all 10-32. The long ones are on the bottom.

They did have 6-32's for the corner frame brackets, 3 per side.

 

[TFB]

I recently did this assembly for post 60k .All the screws are same size,different lengthI believe 2BA,not 10/32.
The upper 2 shorter screws go into a small block held to the frame by a smaller screw,guessing also a BA insteas of 8 or 6/32.The bottom longer screw is the same thread and goes into the lower hole in corner bracket.
I took the longest screw(for bottom) and counted how many turns from thread starting until it hit glass,then marked that number next to hole.Then when I assembled tenonns and stanchions I counted the turns and if it didnt snug before the previous recorded number i shortened the screw.The middle screw holes where the shallowest.
Tom

 

[vivdownunder]

The two shorter screws go in the top and middle staunchion holes. The longer one goes in the bottom where the staunchion thickens slightly.

Fitting a 1mm rubber strip between the tenon plate and windscreen surround is a useful way to ensure the screws don't hit the glass. Such rubber strips were supplied as original, but usually overlooked because they weren't shown in the factory parts book and haven't been available as a repro part. I just cut them from a piece of rubber strip such as that supplied for the glass to frame seal.

It's speculated the rubber strip was an afterthought to better waterproof the screen assembly, and it certainly helps in torrential downpours.

Viv

 

[martx-5]

I'll agree with Tom. Those screws are BA, not the yankee sizes we're used to. Although some of them are very close, they are not the same and the thread angles are also different. For example, a 2BA screw (very close to 10-32) has a major diameter of 0.185" with a thread pitch of 31.4 tpi and a thread angle of 47.5 degrees.

Here's some info on BA and other British threads...

https://www.britishfasteners.com/threads/index.html

Edit: I have found that on the TR3, most screws smaller then 1/4" are usually BA screws. Electrical and instrument screws Iv'e found to be different also, but I'm not sure what they are. So, be careful when measuring, replacing or re-tapping them.