Needed Prewar CWC Shockmaster Upper Strut Reference Dimension Needed!

[Krakatoa]

I need a reference height dimension of the upper strut rod for og men's head tube Shockmaster. Note how drawing a right angle first makes it easy to get an accurate measurement. I am working on a '40 model. If you have one apart I could also use the steering tube height from bottom of lower race to top of tube.

Thanks,

Nate VT

 

[jlively970]

Howdy Nate - I got this as a parts fork, Men’s CWC shockmaster, 40/41.

Hope this helps and let me know if you need anything further!
Josh

 

[jlively970]

@Krakatoa , good or bad info?? Just following up

 

[Krakatoa]

@Krakatoa , good or bad info?? Just following up

Good thank you!

I should have some results to show soon!

 

[jlively970]

Copy that Nate, just making sure you didn’t need any other fork dimensions!

 

[Krakatoa]

I got to this job today and all in all it was a success and I think it came out great. I gotta say CWC made a fine quality product using good materials that stands up to time and abuse. And it is remarkably still malleable and machinable!

Notes:

Fairly certain now the shoot for number on steering tube length is approx 6 5/16 to 6 3/8". This is important because if it is too short there will not enough room for the truss plate stack and top nut engagement. If too long there is a risk of the top nut bottoming without exerting clamping pressure. Good news is this length works for many bikes with 5" headtubes.

I made some calculations and I went with a 7/8" truss rod section to achieve the desired 8 1/8" men's length. I did this because the threads are originally rolled not cut with a die. The diameter of the threads is .024" larger than the diameter of the rod. You won't get a good result simply running a die down these. I learned this from experience ruining a pair of ladies Shelby truss rods a couple years ago. In any case to follow this out I made a small v shaped piece out of .012 shim stock to use as a step up in the v block for the rod end to rest and lined it up on center with the threaded end to tig.

If anyone out in Cabeland needs a similar mod done to their fork please feel free to PM or call to discuss.

And this one is now for sale here:

Primo Prewar 1940 CWC Shockmaster Springer Fork Complete Men's Length Ready to Ride!!

New work! 1940 CWC Shockmaster fork complete as shown with 6 5/16" men's steering tube length, ready to install! Precisely adapted from a low milage un- abused og paint ladies length fork! Steering tube was re threaded to exact men's depth and trimmed to length for standard men's 5" headtube...

thecabe.com

Nate VT
401-548-9082

@jlively970

 

[jlively970]

Nice Job @Krakatoa ! Glad that info helped and was accurate enough. I’m really surprised to find that you couldn’t run the die on the truss rods to cut new threads...

 

[Krakatoa]

Nice Job @Krakatoa ! Glad that info helped and was accurate enough. I’m really surprised to find that you couldn’t run the die on the truss rods to cut new threads...

It was actually the case with the CWC ones being rolled threads. The Shelby I did recently was more straightforward. They were in fact die cut to begin with. I used a 3/8" x 24tpi die to thread those down. My remark regarding Shelby trusses earlier is not accurate I see now. The problem in that 1st case was I used a pipe thread die!

 

[jlively970]

It was actually the case with the CWC ones being rolled threads. The Shelby I did recently was more straightforward. They were in fact die cut to begin with. I used a 3/8" x 24tpi die to thread those down. My remark regarding Shelby trusses earlier is not accurate I see now. The problem in that 1st case was I used a pipe thread die!

So you could use a 3/8” x 24tpi die on the CWC truss rods?

 

[Krakatoa]

No on these CWC yes on Shelby