Pin drive bolts splitting Help Please

[David Kirkham]

You see, what most people (who don't machine) don't realize, is how easy it is to chuck a part up in the lathe and not get it in straight! Happens ALL the time. A collet chuck really helps to bring that concentricity back to 0.

I HATE crappy parts.

David

[David Kirkham]

Notice how we cut the tapered end (the pointed end of this part) right off. Compare to CNGreen's part above with the crack in it

The original Trigo part as a very sharp area where the thread starts (the taper area). The problem is, as that area gets thinner and thinner the steel obviously gets weaker and weaker. Cutting the thread into the part only exacerbates (I learned that word from Jamo ) the problem. Then you torque the boogers out of that thin little starting thread and BAD things start to happen. That first thread will "pull" out and raise up. It will raise up where it is the weakest--right at the end of the thread. That weak area will raise up (remember, only on one side now--right at the beginning of the thread as it only starts in ONE area) and it will cause the pin to tip!

Sounding familiar???

So, we trimmed the point off (remember CNGreen's crack in the taper) and then deeply deburred the thread so it could not pull. This becomes a very important object lesson. Many times you can REMOVE material from a part and make the part a STRONGER part. Here is a perfect example.

Now you know why our parts cost so much. We try to think about everything. Thinking takes time; deburring takes time, programming takes time, finding the right alloy takes time; you get the point. You can purchase cheap parts...but sometimes (well, usually) it will come back to bite you on the bum bum.

Notice the large nose radius on the taper.

[David Kirkham]

Here is a final pic of the finished part. The cool bronze color is from the precipitation hardening. Notice the color was lathed off when we corrected the taper to 90 degrees.

OK, they are now officially for sale. All takers, please contact me!

kirkhammotorsports at gmail dot com

REMEMBER!!!

These are 90 degree tapers!!!

[Paul F]

David, most excellent.

22 please. What's the total with shipping and tax?

[cdnus]

David,
Untill now only the cheap crappy parts were available.
Now because of your dedication to quality there is a Grade A+ & safer nut available.
Now how about us Vintage NUTS

Craig

[David Kirkham]

Paul,

22 each is $8 shipping anywhere in the continental US.

This thread is so long I can't even remember what I said I'd sell the first batch for???

Just call me tomorrow and give me a visa and I'll ship them tomorrow. (I know I have a check of your's too; happy to deal with that any way you want. We have not cashed it.)

David

[David Kirkham]

Originally Posted by cdnus

David,
Untill now only the cheap crappy parts were available.
Now because of your dedication to quality there is a Grade A+ & safer nut available.
Now how about us Vintage NUTS

Craig

We can probably make a batch of them tomorrow, but we will have to figure out exactly what needs to be made first.

David


ps. thanks for the kind words!

[CNGreen]

Thank you SO MUCH David for making our cars safer!

I'm just happy I got to show you and the world the crappy parts I was gonna throw on my car!!



BTW What IS the proper torque rating for this part? I assume no locktite?

[427PMS]

Daivid ,
I am looking for a set of your pins for the Trigos , I sent you a IM

Thanks Chris

[cdnus]

David,
No rush on my account----snowed in till mid April.

Craig

[Dominik]

Great!

I hope the manufacturers of wheels and adapters were reading this...

Dom

[cdnus]

David
After viewing the photos of the finished taper end it looked familiar, so I measured the same ends of the vintage nuts that I am now using.
The end has been machined off flat & remains .040 wide after the inside (thread) has been chamfered @ (looks like 90deg.) to a face width of approx .060. All edges are nicely finished.
So it would appear whoever made these up took the design under serious consideration as have you.
The only shortcoming is the internal hex, which can present a problem on installation & removal if one is not very carefull.

Craig

[Paul F]

I've contacted Trigo, Vintage, and Compomotive about our discussion. Vintage said they would make some comments on this thread. I'm reviewing information with Compomotive. I have not heard back from Trigo.

[jmarsey]

I am running the Compomotives on the jbl. I split one years ago, replaced it and remembered thinking the design was not very forgiving. They are very easy to split if not careful. The car is due for new rotors so I’ll be disturbing these pins. Would love to replace them David.

Paul, let me know if you get specs from Compomotive, otherwise I know I have that old split one here somewhere to measure. Just have to find it.

Thanks David and so cool you are helping out here. Amazing thread.

Talk soon, John

[Paul F]

John, will do.

David's pins are installed. Thanks David!

You can see the difference in these pictures.

This picture shows the Compomotive pin. You can see a shadow caused by the gap between the hub and the pin. The pin has the smaller taper angle. Also notice the fractures at the top of the pin.



This is the same hub with the David's pin. Notice there is no shadow because the tapers match.

[427PMS]

Ahhh , Thats is very nice .
Paul, good picture comparison from old to new
David , excellent job on the pins I didnt think I could be excited to get some pins but I am looking forward to receiving them Thanks

Chris

[jmarsey]

Paul,

Thanks for posting pics. Yes, looks familiar (crack). Hope I can still get a set of those beauties.

John

[Paul F]

I forgot to mention that David's pins, besides fixing the taper issue that David discovered, also fixed the original problem; the splitting pins. I was able to torque them down with no fear of splitting them.

Ahhhhh.

[jmarsey]

Hi David,

Don't know if you got my PM but wondering if your pins are still available, or did I miss the boat?

Hope you can still help me out.

Thanks, John

[CNGreen]

I also need to know what to torque the pins to. Also, should I apply locktite?

David, sorry I haven't posted about the pins yet; unfortunately we've had a death in the family...