Cro-Moly

[J-Dogg]

Hey i only have an ac stick welder and i was wondering if i can weld cro-moly with it?

and if so what would be the best rod for this?

[arcdawg]

while i think that you could do it with a stick machine i would have to be conserned with the h.a.z.

maybe a 7018 rod ?

dawg

[ASKANDY]

Well...What is it that you are welding. While you can probably weld anything with any type of process, the best way to do Chrome-Moly is TIG. You would have to be the judge of the welded parts usage. I wouldn't do a race chassis or any critical weld with it unless you did some serious stress relieving.

Andy

[J-Dogg]

It is for bike frame i am cutting and lenghthining and giving it more rake.

How would i strees relive it?

Thanks Jared

[Tanner]

Surely just buying a new frame would be 400000x easier?

[dyn88]

I think you may be the only guy who would stress relieve a bike frame. All thr well here it is, there are two different ways to stress relieve- first is vibratory this is a controversial method and not approved by everybody. The second is thermal- for mild steel they will heat up the frame to 650 degrees f and hold it there for 1hr each inch of thickness of material(not a concern with the bike frame) at a minimum of 2 hours then they let it cool in the furnace to room temp(in still air).

[fun4now]

prefit it

you might consider getting it all cleande and fitted up and taking it to someone to have it TIG welded. if it is all ready for welding when it get's there it wont caust as much as all they will have to do is just weld it if you have don all the prep.

good luck

[Tanner]

I know I wouldnt ride a rewelded frame unless I TIG welded it, or I had a professional weldor TIG it. Even the thought of stick welds on a bike make me wake up at night with a cold sweat. Then again, biking is my life, so maybe I'm just making a big deal out of nothing.

[J-Dogg]

I no it would be good idea it were going to be riden properly like for trials and downhill but i am just making a chopper out of it

Thanks

[Tanner]

Oh, in that case, like we're doing at school to an old frame - LET 'ER RIP!

[eric75]

What's the wall thickness on your tubing?

The other folks on the forum are welcome to correct me if I'm wrong, but stick is poorly suited for anything less than 1/8" thick.

Something else to consider, since it will be a custom chopper, is the appearance of the welds. Is this a show bike or a kid's bike? Stick will need to be ground and filled with body filler before you paint.

For a bike frame, Stick would be my last suggestion. MIG would be much better. Oxy-fuel welding would also be acceptable. TIG would be ideal.

Since most choppers like you describe are made from kid's bikes, which tend to be overweight, you may be OK. Just remember that non-heat treated welds will be weaker than factory welds, and longer tubes mean higher stress on those welds.

[J-Dogg]

Thanks for the responses

it is about 1/8 of an inch

Since i am only 14 i dont really have enough money for an oxy. All i have is an old stick welder wright now.
I will just weld it then grind the welds down

I am thinking a 7018 would be the best rod any other opions?
Thanks

[HAWK]

J-Dogg,

If stick welding it is the only option, then the 7018 is probably your best choice. However, unless you can locate some 5/64" rods burn through will be an issue. Try to use dry fresh rods as they will burn better. I know they are made and have used them with success. If not, then a 3/32" 7014 on AC or DCSP would be my second choice.

[glockdoc]

Consider using internal or external collars/rings and brass or siver braze together. If your heart is set on using the stick welder the backup rings would definitely help stop blow thru

[fun4now]

glockdoc

If your heart is set on using the stick welder

i think it is a mater of availability. lots of people start out with stick (due to $$$)i started out on O/A cuz i had done it b4 when yunger. O/A would be nice for this but he dosent have acces to it.

a slip ring will help with stick good ideal as it will help with strangth as well as burn through.