: roll bar
Jun 12th, 00, 01:37 AM
I think most of the thread on the roll bar got lost so i'll just start again... I know that toward the end of the thread some users were warning people not to try this at home... and a few others were asking about my welder and commenting on the fact that I had decided to buy a MIG welder and learn to weld vs. paying someone to install it for me. Just to let all know that are interested, I purchased a Craftsman MIG welder 110v .. about their middle of the road MIG. (made by Century) I used .030 wire with a 75%Argon 25% CO2 mix gas. EVERYONE I spoke to (be it from tech departments to manufacturers of the roll bars) said this welder would be just fine for welding in the cage. While learing to weld with scrap metal... I found that I could easily burn through and make holes in both the mounting plates and the tubing ( I don't think penetration was a problem)... I had my welds looked over by a professional welder and he said they looked fine... Not to confuse anyone... I realize that everyone's mechanical abilities vary, and not everyone has access to an experience welder for guidence. So, no, in now way was I suggesting that someone with no experience should just go out and do what I did. But to those of you that do not know how to weld, it is not rocket science, like some would have you to beleive. (people have been telling me for years that welding is extemely difficult) If you get the proper instruction, from both experienced welders and books, and do alot of practicing, I can't see any reason why someone with average mechanical ability couldn't learn to weld and save themselves a ton of money as well as the do-it-yourself satisfaction for the rest of their lives. Like always be sure you know what you are doing... better safe than sorry.
Jun 12th, 00, 04:55 AM
I agree. You could also get some professional instruction. I took a $100 dollar, 7 night course at a local community college and learned to MIG, TIG, braze, etc. Definitely worth the money. This way you practice on someone else's welder until you get used to it.
'69 Base Camaro
355, 200-4R trans
Jun 12th, 00, 05:17 AM
I also agree. I've had welders since I was in high school. I started welding dirt bike frames back together and then built a couple of sandrails/desert buggies and a car trailer. I've still got my $75 Sears arc welder from the early 70's and just sold my gas welder. I'm considering stepping up to a MIG welder one of these days and will when I get to the next project that requires welding. I'd also recommend a class and plenty of practice. I can't even remember the number of things I've welded together for myself and friends over the years.
'69 400SB, Richmond 5-speed; '99 HD Road King Classic
Jun 12th, 00, 03:51 PM
I would just like to throw in my 2 cents worth. I built my first race car, a 67 Camaro that went 10.70's in the 1/4 mile, using a Sears stick welder in the Garage. I sold it about 5 years ago. The car is still together after 22 years and has passed NHRA certification several times. But...those were in my younger and maybe (?) dumber days.
Last year a local racer got very seriously injured when his "homebuilt" car crashed. It basically fell apart under the stress of the rollover / crash after a 1/4 mile pass. This car had passed many a tech inspection. You cannot possibly imagine the stress that a roll cage is under in those types of conditions. If I were to build another car today that ran fast enough to require a full cage....it would be done by a professional chassis builder. My head is too important to me to take that type of chance again.
Just my opinion,
Advanced Automotive Machine
Jun 12th, 00, 04:54 PM
I'm was a welder by trade (now in sales much easier on the body) and agree with bill let the guys who do it all time do the job.
Jun 12th, 00, 05:05 PM
Bill has a good point for cages. TIG wedling is the only way to go when the cage is welded inside the car. The weld puddle and temp. can best be controlled with a TIG welder. But, if you are going to install a roll bar that basically is welded to the floor pans and truck floor then that could be done by a novice welder with a MIG welder. I purchased a Lincoln SP120 mini MIG welder a few years ago and it works great. I have also taken a community college welding course which only confirmed what I learned on my own. The course was good for piece of mind and practice. What I have found to be key is penetration, weld width and not under cutting the stock. Just like anything welding takes pratice.
Jun 12th, 00, 07:25 PM
I'd like to preface my comments by saying I think it's great the way you went about learning to weld. It just scared me a little to think of someone doing a project like this as his first effort.
Another thought, if you sell the car and the new owner crashes it and the roll bar weld fails, YOU could be held liable.
It's scary to think that you might still be held liable for that 67 Camaro roll cage...It's probably an exaggeration on my part to even bring this part up. Yikes! I'm starting to talk like my dad!
Just for gereral info:
The way the mig welder welds is by shooting in wire and burning it up until the metal gets hot enough to melt. You are depositing weld while things are warming up. This means the start of a mig weld on a cold piece should be gone over again when heated up. If you don't get good penetration, it's hard to tell with a mig. It's especially hard to weld thick to thin materials. You should generally not weld one pice of metal to something over twice as thick as the other.
Mig makes a weld bead that has no undercut on the sides like a stick arc would. Actually, an undercut would not be desireable on a stick weld on tubing as it would be a fracture point. But the point is it's very difficult to tell by looking at a mig weld bead if there is good penetration. It's up to the experience of the welder to get it right.
Now, let me tell you I am a big fan of mig welding. It's the first thing I grab when doing repairs on our farm. I've even welded 3" by 1" thick chisel standards together with it and if you get them wrong you will find out quick! I especially like the clean welds with no inclusions of flux like the stick arc has.
I think MIG does a poor job when welding thick pieces together without V ing it out a bunch to build proper heat in the metal. The more surface you weld together the better the mig (or any) welder works.
Where I got caught was the first time I welded with a mig I was welding two pieces of 4" tubing together into a K shaped frame. One of the welds just snapped off and there was no penetration at all of one piece. I was just learning to use the welder and the welds looked fine.
The other time I butt welded 2"X 1/4" square tube to a 3"X 5/8" piece of bar stock. The weld stuck to the square tube not to the bar stock, not enough heat on it to penetrate.
The older I get, the faster I was!
Jun 12th, 00, 07:49 PM
I thought I would tell you we had a I-CAR instructor in our shop a while back talking to us about certification. He told us that people (that have been in the trade for quite a while) that take the I-CAR welding certification test have a 85% fail rate. WOW not as easy as it looks, and looks can be decieving.
Jun 13th, 00, 09:56 AM
Looks like the home welding works only for me...sorry for even posting about it.
Jun 13th, 00, 10:11 AM
Hey.... I liked reading about it.
Jun 13th, 00, 10:42 AM
Soooo did I. It was out right educational, seriously!
Jun 13th, 00, 12:08 PM
I wouldn't get too down about the replys to your post. I think several of the people that responded did so out of concern for your safety. The point I got out of this discussion is that getting a rollbar welded into my car CORRECTLY may be harder than I thought.
Jun 13th, 00, 04:21 PM
Hey all, I was just sharing some info I recieved. I personally love it when people are willing to try to do work they have never done before. Nothing like the satisfaction of finishing a project on your own.
BUT if you need help from someone ask. Its the best way to avoid mistakes. The best newcomers to body & paintwork (my field) are not afraid to dig into a job, and also not afraid to ask for help when needed.
Jun 13th, 00, 05:57 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by mburke:
Looks like the home welding works only for me...sorry for even posting about it.<HR></BLOCKQUOTE>
Don't feel bad. If you had good advice and help I'm pretty shure you did a good job. The thing is, if anyone else reading this shortcuts the job or doesn't get some supervision it could be a disaster.
It's not the place to do your first welding job.
I read a magazine article a couple of months ago where they used a home mig to tack the roll bar together and then took the car to the pro welder. This would be a good alternative for someone who wants to do as much as possible at home but doesn't have the experience to complete the welding.
The older I get, the faster I was!