frame welding

GoldenMotor.com

graydog8josh

Member
Nov 23, 2012
450
4
18
Starkville,MS
Has anyone built a frame themselves? Im wanting to rebuild one out of real structural steel tubing instead of rigid conduit and I'm wondering if anyone has any ideas or tips.

I read that people making frames are using 4130 chromoly, and im wanting to go about the same size as the rigid conduit thinner.

the specs on rigid conduit
1/2 rigid
ID: .634
OD:.855
wall thickness: .110

so im thinking ill get some 4130 chromoly .875 OD, .058 Wall which will be half the thickness

I read people are building downhill bikes iwth .49 wall chromoly but im kinda scared to go too thin on my first chromoly frame, as i dont know how the metal will behave. ..

I do know that the galvanized rigid conduit is such a pain in the... to preclean and reclean and ventilate my shop space and it turns the shielded area around my welds a funny purple color if i get too close to it and that zinc coating turns fluffy and white and contaminates my welds and they end up looking junky.

I just have been using rigid because its really thick and and i got about 50ft of it for free. I wanted to open up my top tube so it would straddle my motor so i wouldnt have to worry about frame clearance issues and now i am opening my mind to doing real structural welding on my bike so i can go real fast w/o anything breaking.

I taught myself to tig weld for this so i really hope someone can give me some good tips and not just naysay. Im going to do it anyway i just what to see whats out there as far as information

So what do you think?
.49 wall or .58 or thicker?
 

dtv5403

New Member
May 4, 2015
322
1
0
USA
I personally have no comment about the thickness or whether this is a good idea or not, I think if you can do the welds correctly than there really is no reason to say it's not a good idea. I will ask you this, though. Have you considered building a lugged frame?
 

caoboy

New Member
Sep 3, 2015
108
0
0
modesto