Chrome moly vs dom

[merc123]

just for the he-- of it i took a piece of 083 1-3/4 and a piece of 065 1-1/2 and welded them this morning. let it air cool for 20 minutes then put them in the vice and beat them to death with a 5 pound sludge hammer bent the end of the pipe flat wore my self out trying to brake it. not a chance no cracks / nothing. so i guess i will stay with my way of welding moral of my story is don't go cheap on the wire and the gas.

Drop a 2300# piece of lead from 5 feet onto concrete. Then drop a 5 pound piece of lead from 5 feet and see which ones has more damage on the concrete... I don't think you're using an accurate example. A 5 pound sledge, or a 100 pound sledge, wouldn't be anything comparable to hitting a wall in a race car at 50 MPH no matter how hard you sling it.

[twisterf5]

Drop a 2300# piece of lead from 5 feet onto concrete. Then drop a 5 pound piece of lead from 5 feet and see which ones has more damage on the concrete... I don't think you're using an accurate example. A 5 pound sledge, or a 100 pound sledge, wouldn't be anything comparable to hitting a wall in a race car at 50 MPH no matter how hard you sling it.

ya your right but we did put some pieces in a press a few years back all welded different and this set up is the best we found. i have knocked some clips off in my time but never had a failure like the pic that was posted. that is why i beat a piece to crap yesterday.it was hit well over 100 time and not even a crack. all our molly is out of germany that is what is printed on the pipe that is what our supplier has. maybe our is stronger than us stuff or what ever they are using. all i can say is it take a 10 time the strength to bend it in our bender and i have not broke any yet.

[50j]

It's hard to see in those pictures but from what I can see it looks like it was mig welded and it broke at the joints. It could have been too much heat, wrong wire, big gaps, too thin a tube, who knows. There's nothing that can't be done wrong. I would probably use DOM on something that'll be on a rough track myself but to break on impact like that isn't normal for 4130. If I used 4130 I would tig weld it only so that I could control the heat. No gaps larger than the rod. Tig welding takes time and skill so there will be people that will try to mig it.

[dirty white boy]

ya your right but we did put some pieces in a press a few years back all welded different and this set up is the best we found. i have knocked some clips off in my time but never had a failure like the pic that was posted. that is why i beat a piece to crap yesterday.it was hit well over 100 time and not even a crack. all our molly is out of germany that is what is printed on the pipe that is what our supplier has. maybe our is stronger than us stuff or what ever they are using. all i can say is it take a 10 time the strength to bend it in our bender and i have not broke any yet.

dont let these experts get ya down man,...your chassis seen to take abuse as good or better than the rockets an mastersbuilts you run with,..an hold up just fine!

[twisterf5]

dont let these experts get ya down man,...your chassis seen to take abuse as good or better than the rockets an mastersbuilts you run with,..an hold up just fine!

no man im good been doing this for 30 years now. like any chat site you can't tell if you talkin to a racer or a seat warmer. but with all the talk i just had to try to brake it(think i pulled something trying LOL .this chassis was built with supers in mind but you right there is not a chassis out there that can take what mine can one tried last year and ended up in a scrap heap LOL you just can't fix stupid maybe he learned.

[rayburn62]

There is no way the heat involved in the powder coating process affects the chassis metalurgical structure. The process simply does not get hot enough. More racer science going on there. Proper filler material, shielding gas, heat, fit and technique all play a roll in the welding of moly.

[twisterf5]

There is no way the heat involved in the powder coating process affects the chassis metalurgical structure. The process simply does not get hot enough. More racer science going on there. Proper filler material, shielding gas, heat, fit and technique all play a roll in the welding of moly.

thought that was funny myself

[Matt49]

To anneal 4130 you have to hold it over 1500 degrees. I doubt you'll find many powder coating operations that go over 400.
Just another example of dynoman trying to pretend like he knows something.

[fastford]

i tried to stay out of this but i cant stand it any longer without putting my 2 cents in the mix, ive been welding all my 4130 with mild steel and a mig ever since it was discovered that its blend creates a flexible enough weld to keep from stress cracking for a long time, as for powder coating, i do it because the bond it has is so great that after a crash or long periods of stress it makes it easier to spot cracks, ive saw cracks that was under conventional types of paint, but the paint didnt crack so you would not have known, JMO

[50j]

I have heard that aircraft manufacturers mig weld it too but it isn't done by Boo Boo with his 110 buzz box. Tig welding lets you back the heat off on outside areas and put more to inside joints. You've got a lot more control over it. All pro level 4130 drag cars are tig welded without exception. Whatever works though.

[fastford]

I have heard that aircraft manufacturers mig weld it too but it isn't done by Boo Boo with his 110 buzz box. Tig welding lets you back the heat off on outside areas and put more to inside joints. You've got a lot more control over it. All pro level 4130 drag cars are tig welded without exception. Whatever works though.

wow, how did you know my name was boo boo? how ever i use a millermatic 200 with a flow meter to control my 75/25 argon. i have used tig and mig and if your joint, and not the one your smoking, is properly fitted , i prefer the mig, but if all you know how to do is braze, then tig would be better

[50j]

wow, how did you know my name was boo boo? how ever i use a millermatic 200 with a flow meter to control my 75/25 argon. i have used tig and mig and if your joint, and not the one your smoking, is properly fitted , i prefer the mig, but if all you know how to do is braze, then tig would be better

Nobody said that you were the Boo Boo, but... As long as the person welding the car up is also driving it have at it. If you're building chassis for other people to drive and they're putting their lives in your hands you have an obligation to do it right. Mig is a whole lot easier and faster and works fine on mild steel. Tig is much more difficult on a chassis because you're welding overhead and out of position a lot of the time but if you're actually qualified to be building chassis it's the way to go with 4130. Yes, I can do both. Educate yourself. Good luck.

[fastford]

Nobody said that you were the Boo Boo, but... As long as the person welding the car up is also driving it have at it. If you're building chassis for other people to drive and they're putting their lives in your hands you have an obligation to do it right. Mig is a whole lot easier and faster and works fine on mild steel. Tig is much more difficult on a chassis because you're welding overhead and out of position a lot of the time but if you're actually qualified to be building chassis it's the way to go with 4130. Yes, I can do both. Educate yourself. Good luck.

where do you get this so called qualification your talking about, is it some sort of certificate or some thing? ive been in some of the biggest and well known shops around and ive yet to see any

[50j]

I guarantee you that you've never been in a shop building pro drag cars and mig welding 4130. A simple call to NHRA would let you know that you can't do it and certify the chassis. My info is firsthand. As far as working in pro level shops, you truly have no idea. Again, educate yourself and then post on the subject. No hard feelings, if you don't know you don't know.

[fastford]

I guarantee you that you've never been in a shop building pro drag cars and mig welding 4130. A simple call to NHRA would let you know that you can't do it and certify the chassis. My info is firsthand. As far as working in pro level shops, you truly have no idea. Again, educate yourself and then post on the subject. No hard feelings, if you don't know you don't know.

90% of people on here ,including you, have probably never held a mig or a tig, and as for your dragracing statement , thats why i quit fooling with that BS a long time ago, ive welded nearly every thing known to man over the last 30 yrs, but you dont have to believe me thats your right, no hard feelings here either, have a good day

[50j]

Like I said, make the call. I could make you look real ignorant right now but I'm not into whizzing contests. Pride and stupidity are found together, and you're hurling personal insults at someone you know nothing about. I have the credentials but I'm not interested in putting a resume on the internet.

[fastford]

Like I said, make the call. I could make you look real ignorant right now but I'm not into whizzing contests. Pride and stupidity are found together, and you're hurling personal insults at someone you know nothing about. I have the credentials but I'm not interested in putting a resume on the internet.

i could make the same reference to you, and like the famous forest gumps mama said " stupid is as stupid does" take it any way you want, the end.......

[50j]

i could make the same reference to you, and like the famous forest gumps mama said " stupid is as stupid does" take it any way you want, the end.......

Everything I said was 100% accurate and can be confirmed with even minimal effort. The type of rod, shielding gas, and procedure is what is used in pro chassis shops. NHRA, SFI, and now circle track chassis builders agree that it should be tig welded. You however are more brilliant than than the people who have been building hundreds of cars, structural engineers, and the people doing the testing because you have a Millermatic and a Flow Meter. Big deal who doesn't have one. If you look at your super duper spool it's probably ER70-S2 wire, maybe ER70-S6. You just can't control the heat as easily. Go back to beating tubes with a hammer for testing. I don't know where some of you people come from, but I've never seen a forum like this where people don't want correct information.

[JustAddDirt]

How does Rocket weld their moly cars? i know it is mig welded, but do they stress relieve it?

[fastford]

Everything I said was 100% accurate and can be confirmed with even minimal effort. The type of rod, shielding gas, and procedure is what is used in pro chassis shops. NHRA, SFI, and now circle track chassis builders agree that it should be tig welded. You however are more brilliant than than the people who have been building hundreds of cars, structural engineers, and the people doing the testing because you have a Millermatic and a Flow Meter. Big deal who doesn't have one. If you look at your super duper spool it's probably ER70-S2 wire, maybe ER70-S6. You just can't control the heat as easily. Go back to beating tubes with a hammer for testing. I don't know where some of you people come from, but I've never seen a forum like this where people don't want correct information.

the stay the he!! off here FOOL