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Here is what I'm looking for. Picture a long 4-40 (or 3mm) setscrew that has a hollow center. I need it for the Bullet project, it needs to be brazed to a piece of piano wire. I can't use the DuBro style solder on pieces shown in the first pic as they are far too weak. The rod needs to go thru the threaded part. Below are pics of what they used. I have been all over McMaster Carr and didn't see anything close.

I may be able to use a 4-40 or 3mm helicoil. I had no idea they made them that small lol! They ain't cheap either

This might be what you need. Seach ebay for Tamiya Special Rod End Set Super Champ/Hilux/Blazer/Ranger/Sand Scorcher/ Brat

What about axial ball end stud or I think I saw some thing like that at rc4wd

helicoil won't work, as it's for an internal thread, not an external one.

they probably made some 3mm specially modified threaded tubes. Here is an option for you: find long 4-40 or 3mm set screws, like 10mm long or whatever you have estimated, and braze into the hex portion of the set screw. you won't be able to drill them through, because they are too hard.

brazing will be stronger than solder and even just the end in the hex will be more than strong enough.

Can you thread a piece of tubing with a die and then cut it to whatever length you want?

How about 4-40 allthread use the brass tamiya shock sleeve bushing thingy braze over end allthread.You can make them from brass tube at hobby store then have the depth needed to solder or braze the long rod into it.DON

You could use a socket head screw and silver solder the wire into the socket head of the screw. I did this when I made some sprint bars for my Losi short course buggy. Let me know the dimensions of what you you need and I'll make them up for you.

Thanks guys, lots of good ideas. I need the visual stylings of the original so I think I will try some hollow setscrews first, although the cap head screw idea may work as well if I can turn the diameter of the head down enough.

Did you win the auction???

Yes! All 3

jwscab wrote: you won't be able to drill them through, because they are too hard.

What are you talking about willis?! I drill them all the time. Slow speed, hard feed pressure. Yes, one's small as 4-40 might be tricky but not impossible.

In the future look thru rc airplane hardware at tower hobbies and you'll find some there.

Not the same. I have tried Sullivan and DuBro, and looked at many others. These are hollow so they rely on the piano wire for strength. A pushrod end from model airplanes soldered on would bend way too easily.

The one on the mockup is an aircraft one cut down.

Ohhh. I see you checked out every avenue.