Frame Bracing Photo Collection

531blackbanshee wrote: here are some tig faq's from lincoln ele.

TIG WELD 4130!
The Lincoln Electric Company, Welding Services. June 2000



Yes, you can TIG weld 4130 tubing up to .120" wall thickness easily with the techniques and procedures described in this bulletin. Answered are the top ten most frequently asked questions about TIG welding 4130 Chrome-Moly. These attached procedures apply to typical sporting applications such as experimental airplanes, racing car frames, roll cages, go-carts, bicycles, and motorcycle frames. The suitability of these techniques and procedures must be evaluated for your specific application.

Q. Can I weld 4130 using the TIG process?
A. Yes, 4130 Chrome-Moly has been TIG welded in the aerospace and aircraft industries for years. As with all welding, proper procedures and techniques must be followed.

Q. Do I need to pre-heat?
A. Thin wall tubing (< 0.120" wall) applications do not typically require the normal 300ºF to 400ºF pre-heat to obtain acceptable results. However, tubing should be at room temperature (70ºF) or above before welding.


Q. What filler material do I use?
A. Although there are several good filler materials, ER80S-D2, is one you should consider. This filler material is capable of producing welds that approximate the strength of 4130. ER-70S-2 is an acceptable alternative to ER80S-D2, as is ER70S-6, although the weld strength will be slightly lower.

Q. When I use ER70S-2 filler material, do I give up strength for elongation?
A. Yes. The filler material, when diluted with the parent material, will typically undermatch the 4130. However, with the proper joint design (such as cluster or gusset, for example), the cross-sectional area and linear inches of weld can compensate for the reduced weld deposit strength.

Q. Why is 4130 filler metal not recommended?
A. 4130 filler typically is used for applications where the weld will be heat treated. Due to its higher hardness and reduced elongation, it is not recommended for sporting applications such as experimental airplanes, race car frames, roll cages, etc.

Q. Can I weld 4130 using any other filler metals?
A. Some fabricators prefer to use austenitic stainless steel fillers to weld 4130 tubing. This is acceptable provided 310 or 312 stainless steel fillers are used. Other stainless steel fillers can cause cracking. Stainless filler material is typically more expensive.

Q. Do I need to heat treat (stress relieve) 4130 after welding?
A. Thin wall tubing normally does not require stress relief. For parts thicker than .120", stress-relieving is recommended and 1,100ºF is the optimum temperature for tubing applications. An Oxy/Acetylene torch with neutral flame can be used. It should be oscillated to avoid hot spots.


Q. Do I have to pre-clean 4130 material?
A. Remove surface scale and oils with mild abrasives and acetone. Wipe to remove all oils and lubricants. All burrs should be removed with a hand scraper or de-burring tool. Better welding results with clean materials.

Q. Do I need to back-purge 4130 material?
A. Backpurging is not normally necessary, although some fabricators do. It will not hurt the weld and may improve the root pass of some welds.
.

Q. Should I quench the metal after I finish welding?
A. ABSOLUTELY NOT! Rapid quenching of the metal will create problems such as cracking and lamellar tearing. Always allow the weld to slow cool.

More Information on TIG Welding Chrome-Moly 4130

Find out more about Lincoln Electric's professional line of TIG welders here
Or, check out Lincoln cut length TIG welding filler metals here

WELDING SPECIFICATION: Aircraft and Motorsports

GENERAL INFORMATION

Remove all oxides and burrs within 3" of weld area.
Acetone wipe to remove all cutting oils.
Assemble and tack weld in joint in a minimum of four (4) places with TIG.
Tubing should be at minimum temperature of 70ºF (room temperature.
TIG weld per parameters specified using Lincoln's Precision TIGâ„¢: The Power To Perform. 185, 275 or 375.

they have been oxy acetelyne welding hobby airplane frames out of chrome moly for a long time.anyone who is skilled at o/a welding can weld a frame up or modify it without having to worry whether the welds are going to fail or not,they aren't if you did it right.
plus when you do finally get a tig you will already have most of the skills built up by doing the o/a welding.
that's my .02 anyways.

leon

Some info on frame jigs: www.chopperhandbook.com/jigs.htm

leon

chain line processing.









leon

leon

Leon - I'm a novice welder - I see mention about heat treating and making the frame brittle. What should be done to prevent this from happening?[/quote]

doubledub,
do plan to use mig or tig to weld your braces in with?









leon

531blackbanshee wrote:

DoubleDub wrote: Leon - I'm a novice welder - I see mention about heat treating and making the frame brittle. What should be done to prevent this from happening?

doubledub,
do plan to use mig or tig to weld your braces in with?

I have access to an oxy acetylene torch and a tig welder. Likely it will be with the tig.

Yes, Beuatiful Tig welding.
I just raked a frame, sorry if it is a project.
I like looking at current events and stuff.
I gusseted this KZ frame at the neck.
Hope my post don't get in the way of anyone's

Gee? Am I allowed to post a 10 year old PROJECT Picture?
This is old school.

DoubleDub wrote: In preparation for my frame bracing on my 650 racer I collected a bunch of bracing photos from various members new and old. Just thought I would share the wealth. Feel free to add more if you have them!

doubledub,
the tubing on these frames are thin enough that as long as they are warm enough not to condense when they start to heat up you can tig them and let them cool naturally without worry of embrittlement.

1/8 inch "breather" holes in the tube will help keep gas from building up inside the sealed tube and causing bugholes in your welds.a spot weld after all the welding is done seals em right back up.

if it is cool,a pre-heat with a propane torch to get the tubes to 100 degrees or so to remove any moisture will be in order.

hth,

z1kzonly and 79mk11 thanks for the additional pics.

leon