Welding Question

[Falcon351C]

Hey Guys,
Im welding up a cage in my 64' falcon. I purchased the main hoop from chris alstons chassis works....which is a mild steel hoop...and a friend of mine just gave me a few pieces of chrome moly tubing. Will I have any problem welding the mild steel to the moly? I will be using a mig welder...any special wire I need to run? Any problems i may run into? Sorry this isnt a buick question...but I have much respect for the buicks..and the owners on this board...thats why this is the only board I look at. Thanks in advance.

 

[EightSecV6]

You CANNOT mig weld mild steel to chromoly, it is not accepted by the NHRA ( will cause cracks in the chromo.) If you use all mild steel you will be fine, any piece of chromo. you add must be tig welded.
Bill

 

[6PacktoGo]

Adding chrome moly to mild steel is not the best idea. It can be done, but you MUST use the TIG process. Contrary to popular belief, chrome moly CAN be successfully MIG welded, but it requires the touch of a true expert, I've been welding for 20 years and I would not attempt to weld mild steel to chrome moly with a MIG welder. Also note that mild steel filler rod is often used to weld chrome moly to chrome moly, in order to increase ductility. Mark Williams even suggests you do so in their instructions for their chrome moly dragster and funny car chassis kits.

I use mil spec 1.625" X 0.120" DOM mild steel tubing to build race cars as a minimum acceptable material. The only other acceptable material for me is mil spec 4130 chrome moly 1.625" X 0.090".

Technically, what you propose is illegal in both NHRA AND IHRA. I would suggest you acquire the proper tubing, and do it right. You can probably get by, depending on how good the tech inspectors are. And how good your welder is.

 

[10SV6]

If you've got a MIG welder just go get mild steel tubing.

A little off subject - The amateur aircraft guys use a lot of cromemoly in making up their airframes. The majority of it is oxyacetelyene gas welded. You want to talk about some ugly welds.

 

[Falcon351C]

Aww man....

Well thanks for the answers guys...even though it wasnt what I wanted to hear lol All the pieces are notched and ready to weld...but....i'll just take your advice...and use all mild steel. I was only going to do this..since it would of saved me so much time...but....I know I have to do it right. I'll find something else to put the choremoly cage in. Thanks for saving me alot of headaches down the road.