Small lot heat treat shop for DD rivets?

pfarber

pfarber

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pfarber
I have to repair some wheels and I need to get the DD rivets I have heat treated (annealed?) for the springs (old Goodyear brakes).

Anyone in the SE USA know of a shop that can HT the rivets and ship on dry ice? Or maybe a really good knife/metal smith that has a HT oven in the SE?

Thanks
 
Check with the crew at Air Corps Aviation. I know they had to search a long time to find anyone that was qualified to make some special rivets they needed for a restoration.
 
The temps don’t have to be that high.

Maybe an electric heater element and monitor with a laser temp?

Once heated; make sure you keep them in dry ice right till the moment

of driving them. A coffee or lunch break and you have to start all over

again.


Just for grins you may want to try driving a thawed one on scrap.

The use a 10x glass and check for cracks.
 
From what I’ve read 2024 alloy rivets need to be heated to 910-930°, quenched, and then driven within 20 minutes. If I needed to have DD rivets replaced I’d have a qualified shop do the work.
 
My WAG is a small amount would be treated as a ”Custom Job” which will

make it extremely pricey. Then you have to assure that they are not

allowed to warm during the entire chain. It will be very apparent when

driving if that has happened. They do “ keep “ with proper refrigeration.
 
D and DD rivets are a lost art... I could use E rivets but I also have the problem of driving hard rivets... so the cost of a pneumatic squeezer that can do E6-6 is gonna be way higher than driving to a shop that can heat treat and I take them home on dry ice.

One poster is correct.. 910-930F for 30min, quench and use within 20 minutes OR place in freezer at < 0F for up to 90 days.

A low end HT furnace is $500, there are DIY furnaces that knife makers use that can be put together for $300-ish. But I'm hoping somewhere in the SE US there is at least one shop that can warm up 10 rivets for me.
 
Tifton GA, about a S.E. USA as you can get. Convince him that he wants to make a riveting video. :) (Keith does do work for viewers, no idea how much he charges)
 
Is there no other way to fix this part?
Send off to the appropriate CRS?
What exactly is it?
 
I do recall substituting Hy-Loks for the DD’s in a couple spots.
 
Magman said:
I do recall substituting Hy-Loks for the DD’s in a couple spots.
Click to expand...
Its for a wheel so the shop head needs to be formed to the contour of the rim. Monel (E) rivets are the usual substitues, but I can't set a 6-6 without buying bigger tools. I can set a DD6-6 when annealed quite easily. Also substituting would be a major airframe repair.
 
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Let'sgoflying! said:
Is there no other way to fix this part?
Send off to the appropriate CRS?
What exactly is it?
Click to expand...
The manual only lists MS20426DD6-6. Substituting would be a major airframe repair. FAR 43 Appendix A (b)(1)(xvii) wheels. If I use the proper rivet then its just maintenance. The operation is riveting a locking spring to the outside of a wheel. Its an old Goodyear brake system.
 
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If you can’t find a heat treat shop find a place that does pottery. A small pottery kiln can get up to those temperatures and be controlled to stay there.
 
The DD’s can be like butter when annealed.
However; assure your tools are up to the task as well.
Using a light gun or light bucking bar will result in multiple light
hits that will work harden the rivet and cause it to crack.
You want complete the process with as few blows as possible.

One time there were two folks doing the riveting plus the inspector.
After the rivet was driven the inspector would examine with a mag glass.
MANY had to be carefully removed due to cracking. This was very
awkward to access and a blind rivet was not permitted in that location.
There were a great deal of rivets removed but the ONE difficult rivet
was successfully completed and ready for shaving.

btw- This was 3 people in a 12 hour day and there was no goofing off.
 
pfarber said:
The manual only lists MS20426DD6-6. Substituting would be a major airframe repair. FAR 43 Appendix A (b)(1)(xvii) wheels. If I use the proper rivet then its just maintenance. The operation is riveting a locking spring to the outside of a wheel. Its an old Goodyear brake system.
Click to expand...
we’ve covered repairs - what about replacement instead?
You didn‘t say what aircraft.
Maybe a Cleveland upgrade?
 
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