Heavy Nut

[Bradrock]

The flap push rod requires "heavy nut" to be welded to the end, on plans #12. Could someone clarify "heavy nut" please? Does AN315-5 fit the bill, or is there a heavier option?

[Enewton57]

Bolt and nut supply companies carry them. Just do a search for heavy nut on Google and you will find them. They are a longer nut with more threads to give added strength. As an alternative you could weld a regular nut and a thin nut together. Thread them onto a bolt and align the flats, but don't tighten them together. Tack weld on three side and remove. Weld together. You might need to run a tap through to clean out any slag after.

[X'N]

I bet you could cut down a coupling nut too. Or is that the same as a heavy nut?

[bestbearhawk1231]

I went to Fastenal to get mine. They are used for structural steel applications like steel framed tin buildings. The nuts are longer than a standard nut and bigger diameter. They had to order them in since the fine threads are kinda odd ball in my neck of the woods. I welded 2 heavies end to end then welded the assembly onto the ends of the push rods. I didn't like the thought of only having one nut on the end so I doubled them up, they are about the length of a coupling nut cut in half. I used a bolt to position the nuts properly but you need to make sure that you remove the bolt while the nut is still cherry red or you will never get it out. I had to work a tap through each nut a couple times to get the slag out so the bolt would thread in nice. Take your time with the welding and tapping. It worked better for me to weld 2 flats at a time, remove the bolt, tap the threads, insert the bolt, weld 2 more flats and repeat the process. There was a lot less slag build up that way. Take your time with the tap and used lots of cutting/tapping fluid. I use mystic metal mover for steel cutting, drilling, and tapping. If you break the tap, you are starting over.

[mswain]

mcmaster carr carries them too. that is where i purchased mine.