Sling Pilots Forum

This is kind of embarrassing, but I just finished fabricating the frame for my DRDT-2, and when I attempt to insert the dimple dies they won't go in without shearing the O-rings that are on the pins. I've oiled them and attempted to gradually rock them in but the O-rings are just too large to go on without damage. Is there a trick here or did they put too large O-rings on the dies or something?

Based on my experience it does take a bit of pressure to get them to seat into the DRDT-2... Once you get them in there a few times they go in easier. After finishing my plane they take a bit of encouragement to remain in the slots.

I don't think the o-rings should/would shear off though...

FWIW, I had the same problem, called the DRDT maker in AZ. Ended up shearing my o-rings off in the DRDT. All good now.

STGove wrote: ↑Sat Jun 15, 2024 4:42 pm FWIW, I had the same problem, called the DRDT maker in AZ. Ended up shearing my o-rings off in the DRDT. All good now.

So you just kept using the sheared O-rings? I guess that's an option, although it seemed once they were sheared off the didn't hold so well.

I wonder if the problem is just that the chamfer in the mounting hole is too sharp, maybe I'll try rounding it a bit.

Again, just an FYI, and YMMV, but the guy who designed the DRDT told me if the dies get loose, just put on some tape to hold them in place.

I had the same problem. Inserting the dies into the DRDT2 was difficult. When I used the arm to force them together, the outer part of both o-rings were sheared off. After that, they don't stay in the machine very well.

My solution was to simply put a thin piece of plastic (from a shopping bag) over the shaft of each die, then press them into the machine again, assisted by the lever. That adds just enough resistance so they don't fall out, but I can easily twist them out when needed.

FYI, I added a loop of steel wire in place of the O-ring. This worked so well I couldn't get it out again, and when I tried to pry it out the shaft snapped. Beware, those things are apparently really brittle (and expensive, I was quoted EUR 115 plus tax and shipping to get a new one).