Carl Goldberg mounts for red postage stamp backplate reedies

Balogh,
I have no interest in these, but if you pull off a neat trick, I'll make sure to get a Dubro clip to "the stateside distribution point." Feel free to hit me up if you gain traction in your quest. Until then, I will try to find a way to get the clip to you.

Ron, Jim,


Thanks for your generous offers.


I got a few 3D courtesy pieces from Jason Wi and also bought from Bernie some 3D printed mounts that Jason Wi produced, but I saw that the last pieces were sold out by Bernie some time ago, so I thought Jason's production run has been over.

My 3D units have been partly utilized but some also snapped...I boiled others in hot water in hopes they will soften up like the black COX props..

International shipments are unreliable during Covid times (it has been almost a month I have been waiting for Dick Russ' 1/2A Streaker to arrive here from Oklahoma, with no sign of its whereabouts whatsoever..in pre-Covid times it took 9days for Bernie to ship here from Canada or Matt to ship from US)  and I thought if someone on CEF volunteers to stock the 16 from ebay then later when Covid shipping miseries are over I could buy some from that stock...

I can try printing out of glass fiber and carbon fiber zytel. Standard zytel is brittle just off the printer. I do boil them to anneal them but that may not be enough as they will dry out again in arid environments.

Not sure I can add much more thickness anywhere without it fitting like the CG molded one. Where do these tend to break?

Thanks Jason, they mostly break where the thin plate intersects the thicker bracket. Some break already under the torque when the spring starter is wound clockwise, some later due to engine vibration. Some were cured well with boiling.

Maybe with a bit wider slot for the spraybar up and down you could afford a bit thicker plate with glass fiber?

im good for 2, but not all of em...

I could volunteer to buy the pack of 16 but a 27% Value Added Tax plus import duty is added in Hungary...plus I am not sure how long it takes to ship here...so someone in the US should better buy the package and resell it to whoever are interested on CEF in smaller lots. I am in for 3 or 4. The auction ends in a few hours though. The Goldberg mounts are rarities nowadays and I would regret to see this opportunity go...

Jason_WI wrote:I can try printing out of glass fiber and carbon fiber zytel. Standard zytel is brittle just off the printer. I do boil them to anneal them but that may not be enough as they will dry out again in arid environments.

Not sure I can add much more thickness anywhere without it fitting like the CG molded one. Where do these tend to break?

Jason, do you think you could form a ”chamfer” into the inside corners between the thin part that faces the engine backplate and the thicker part that works as a spacer? Maybe between the triangular part and spacer part too?

Sometimes sudden changes in thickness of a structure cause stress concentrations, that combined with the vibration... A chamfer (not sure if it’s a correct term for the round ”fillet” shape that I mean) would spread the stress over a larger area.

Not sure if I could explain this in a way anyone understands, but imagine it being steel, about 20x the size and with a nice thick continuous weld seam done by a pro into all the inside corners of the part

Kari,  yes this is what is called "stress relief by smooth transition " in stress analysis. I was also trying to add that chamfer or fillet from CA glue to relieve the stress, but CA does not adhere well to the material of the mount.