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jason@gmachine
06-04-2007, 07:24 PM
i just finished this roll-bar setup for a 65' chop top. The car is going over to Stangwerks to get the top chopped 3" in the rear and 4" in the front. Its MIG welded 4130 with TIG welded removable harness bar.

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Jason

jason@gmachine
06-04-2007, 07:25 PM
harness bar
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Jason

jason@gmachine
06-04-2007, 07:25 PM
4130 sub-frame connectors!
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Jason

Kenova
06-10-2007, 12:44 PM
You'll have to post a pic or two when the chop is done. Should be interesting.
Ken

jason@gmachine
06-11-2007, 11:49 AM
yeah and i think we are going to be putting out 3-link kit on the rear and a new front setup with coilovers in front so he can run a bigger engine!


Jason

RobM
06-13-2007, 03:41 PM
bad ass.

How tall is the driver? i know im 6' 2'' and could even come close to fitting into a mustang with a 3 inch chop unless the seat was set down lower.

jason@gmachine
06-13-2007, 04:57 PM
bad ass.

How tall is the driver? i know im 6' 2'' and could even come close to fitting into a mustang with a 3 inch chop unless the seat was set down lower.


he is about 5'10" but i think this is just going to be a SEMA car only, he wants it to showcase his paint skillz!


Jason

RobM
06-14-2007, 02:40 PM
sounds cool.

silver69camaro
06-25-2007, 12:32 PM
"Its MIG welded 4130 with TIG welded removable harness bar. "

Just curious, why was MIG used on some parts? Most chrome-moly parts welded with MIG must be stressed relieved post welding.

jason@gmachine
06-26-2007, 09:54 PM
one reason, cost, the customer did not want to pay the extra labor cost to have it TIG welded.

"Most chrome-moly parts welded with MIG must be stressed relieved post welding."

Maybe i was taught differently but MIG welding 4130 is more forgiving than TIG welding 4130 and does not need to be stress relieved. The only 4130 welded part that Needs to be stress relieved is something welded with 4130 rod and not ER-70s. Most MIG welded parts that are 4130 are done so because they don’t require it to be heat treated.

Ex. Herman Motorsports MIG welds their chassis for this very reason, there is much more of a tendency for a TIG chassis to have stress cracks in the long run.

Another Ex. the Rear trailing arms on our Class 5 are MIG welded 4130 because we are not going to heat treat them and they have less chance for stress cracks with the MIG setup.


In many cases MIG welding 4130 is safer then TIG.


Jason

silver69camaro
06-27-2007, 05:20 AM
I agree about not using 4130 rod, and using ER70S. Even so, if I'm not mistaken, NHRA mandates that no chrome-moly cage be MIG welded, only TIG can be used.

I disagree with MIG being safe due to heat control. I always find more control with TIG. But that's not to say it's totally safe with TIG, as a very small bead can have faster cooling rates and be failure prone also...so it largely depends on the weldor.

Honestly, I'd use oxy/acetylene before MIG. But that's just my opinion.

jason@gmachine
06-27-2007, 08:53 PM
I agree about not using 4130 rod, and using ER70S. Even so, if I'm not mistaken, NHRA mandates that no chrome-moly cage be MIG welded, only TIG can be used.

I disagree with MIG being safe due to heat control. I always find more control with TIG. But that's not to say it's totally safe with TIG, as a very small bead can have faster cooling rates and be failure prone also...so it largely depends on the weldor.

Honestly, I'd use oxy/acetylene before MIG. But that's just my opinion.

well then we stand on complete opposite sides of the MIG argument. Im sure that our NASCAR chassis that was 4130 was also unsafe as well as this class 1 and TT. LOL.

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Well we can at least agree on something, that we disagree on the use of MIG with 4130!

no hard feelings though, i have always liked your products.

JAson

silver69camaro
06-28-2007, 05:20 AM
...so it largely depends on the weldor.



This is pretty much my final thoughts. I know MIG can be done, which is great due to a large fillet bead, but I guess it just depends on the operator's skill.

Wonder why NHRA requires TIG and NASCAR does not?

jason@gmachine
06-28-2007, 12:19 PM
This is pretty much my final thoughts. I know MIG can be done, which is great due to a large fillet bead, but I guess it just depends on the operator's skill.

Wonder why NHRA requires TIG and NASCAR does not?


im right there with you on this one, same with SCORE. It really is confusing because the forces that a TT chassis sees are greater than the forces a NHRA chassis will see. But then again i see some really scary stuff out at the off-road races! LOL.



Jason

RobM
07-01-2007, 01:50 PM
wanna see scary go to a dirt oval track in a really small town.


how do you guys stand on brazing chassis together on lighter weight vehicles? alot of the formula type cars are brazed together. Im pretty sure scca alows a brazed roll cage in some classes. the joints have to be very tight though

quadfather
07-02-2007, 04:04 PM
i feel only a tig should be used on 4130 . part of the reason is the tig has a post flow gas that keeps the weld area from being contaminated as it cools. also with the tig you have much better control of the heat used . i never did understand why the offroad stuff is migged. and i think most of the the stock car stuff is mild steel. i don't see why anyone with a tig would choose to use the mig instead. in my case, i take pride in my work and choose to use a tig because the end product looks more apealing to the eye. i believe if done properly the mig could be safe on 4130 , but why take a chance on a roll cage?

jason@gmachine
07-05-2007, 07:56 PM
using MIG has nothing to do with not taking pride in our work, or at least that is how you came across. I can and have TIG welded 4130 chassis and im currently TIG welding my class 5, which is taking forever. I do not suggest that everyone can weld 4130 to a proper level but in my hands i can weld a 4130 cage with MIG or TIG and they will both come out very safe and do their job if the situation were ever to arise.


why is some off-road stuff MIG welded?

well one answer is because the MIG weld is more forgiving and can "give" a little so the stress on the heat affect zone is reduced. With a TIG chassis you need to check all the welds for cracks after a race and all the suspension parts. With MIG welded 4130 there is less of a chance for the stress cracks. A good example of this would be our rear trailing arms on our class 5. They are MIG welded 4130 because we have found that TIG welded 4130 arms are prone to stress cracks after a race.

Jason

silver69camaro
07-06-2007, 11:40 AM
They are MIG welded 4130 because we have found that TIG welded 4130 arms are prone to stress cracks after a race.

Jason

Assuming the same filler is used for both processes, I assume this is the case because of the larger bead/fillet radius from MIG?

Looks like I opened a can of worms with this one. Sorry!

RobM
07-09-2007, 02:08 PM
MIG has a smaller heat affected zone.

Some really high end custom Bicycle frame fabricators (road race bikes) only braze their frames together because a TIG welded frame is much more stressed and needs to be heat treated

I bet if you TIG welded then heat treated those trailing arms on your Buggy they wouldn’t crack. But this would complicate the whole deal quite a bit

jason@gmachine
07-09-2007, 03:57 PM
Well actually we found that both non heat treated TIG welded arms using ER70-s had problems with cracks, and so did the heat treated TIG welded with chromo rod arms. To date all the trailing arms are MIG welded and now hold up great with no cracks. On the new car we will see how the MIG ones work because we are planning on bashing this chassis three times harder than other class 5 cars.


Can of worms?
Yeah this is an ongoing debate that has done nothing but gone in circles. Everyone has their own way of doing things and I still stand to the idea that the skill of the welder is the main factor in any failure of a weld.

No hard feelings either way to anyone!

Jason