Snap Measurements for '29 Phaeton/Roadster
 

I'm resurrecting this topic because my research turned up two answers from the forum: One posted originally by Tom Weserberg ca 2011 and one posted by Brent more recently. Both good sources! I've attached both for clarity. Note that my questions below are only in reference to the snap holes.

Frame width: Brent shows 43" and Tom shows 42 3/4". Oddly, my new frame is 42 7/8" from Mike's. What is common to both pictures is that the first holes from either side are about 1 1/2" in and the 2nd and 3rd holes from the passenger side are each 10" and 20" from the initial hole, resp. In both cases the wiper center (with or without a hole) is 11 1/2" (!0"+1.5") from the driver side edge.

Put another way, the 5 main measurements (four 'main' holes and center of wiper) are exactly 10" apart and centered as a group on the frame.

The principal difference between the two pictures is the gap between the snaps surrounding the wiper center: for Tom the gap is 5" (leaving 7 1/2" to each of the nearest snap holes), and for Brent, it's 2 1/2" (leaving 8 3/4" to each of the nearest snap holes).

Two questions:
(1) What is the 'right' gap between the snaps surrounding the wiper arm? I would think that you'd want the opening around the wiper post to be as small as possible, ie, closer to Brent's picture, for resistance to water or air leakage around the slot where the wiper post comes through. (Am I correct that for '29 there is no hole: the post comes over the frame?)

(2) Brent shows the snap holes being centered from top to bottom on the frame . However, Tom shows the holes being centered 1/4" (16/64") from the bottom. Since the holes themselves are 19/64" (slightly smaller than the 5/16" snap), this is clearly not possible, since the hole is bigger than the distance from the lower edge. So my question is: are the holes centered from top to bottom, as Brent shows, or should the holes be lowered from center and if so, by how much?

Thanks for any advice or insights!
Tom

Re: Snap Measurements for '29 Phaeton/Roadster
 

Re: Snap Measurements for '29 Phaeton/Roadster
 

Brent has been very helpful. His experience has always been to center, though he offered to check the archives (once they’re open).

In the meantime I’d love to know if anyone has experience or seen snaps not centered vertically?

Re: Snap Measurements for '29 Phaeton/Roadster
 

Find an original frame and check?

Re: Snap Measurements for '29 Phaeton/Roadster
 

https://www.fordbarn.com/forum/attac...p;d=1632449271
Snap Measurements for '29 Phaeton/Roadster

Re: Snap Measurements for '29 Phaeton/Roadster
 

Final question: has anyone ever seen snaps on any Model A open car that were NOT centered top to bottom? Tom’s picture clearly shows them to be lower than center. If lower is better, how much lower? 1/4” from bottom edge is indicated, but that would put the snap less than 1/8” from the glass and the roof material would be pressed against the glass.

Thoughts?

Re: Snap Measurements for '29 Phaeton/Roadster
 

The window frame on my 28 is bare metal and has a deep scribe line on snap hole centerline. Using a caliper held at an angle sufficient to catch the edge, the scribe line is about .290. Why was this windshield frame scribed and hand drilled ? One can only guess that the guy using a drill press with drill jig could not drill enough to keep up with the rate, or maybe the drill jig was in the maintenance shop; who knows. The holes are not all perfectly centered on the scribe line, and some are not very round either.