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I am getting ready to put my 1932 frame together and want some opinions on the subject. I have had guys that TIG weld tell me that it looks nice and all, but there is a very high heat transfer which can affect metal hardness. On the other hand MIG does a good job, but some say it isn't strong enough.
Now I know back in the 50's when guys were building rods they only used ARC welders. Is it really just a matter of preference?
I think it is a preference. My 33 has 550hp (dyno'd) and I built my frame using a MIG. No problems at all. If you are a good welder than you wouldnt have a problem using any type of welding.
I've used all three processes.
I use TIG for most things now, but I wouldn't hestitate to use the others in certain situations.
TIG is going to require good fits and clean metal. I think it looks good, but that's just my opinion. I like the control it gives you. You can do things that are next to impossible with any other method.
If you can't get the metal perfectly clean, then stick will likely give better results. It's also good in tight and/or deep places with limited room. I have a couple places on my T that will get E7018 stick welds for this reason.
Mig is probably the easiest to use, but it's also pretty easy to screw up. You can get welds that look good, but have no real penetration.
Bottom line is, use what you are 100% confident with. The important thing is consistent strong welds. You can get that with all three if you practice enough.
By the way, you would be surprised at how many airplanes and race car frames were gas welded and brazed together in the old days. Not that I'm recommending those processes, but I have used them.
I'm pretty good with a stick, better with a MIG, but I have never done TIG. I am probably going to go with MIG. All steel is new or bead blasted so it should not be a problem.
I agree. Also, TIG is alot more time consuming than MIG or stick.Quote:
Originally Posted by Uptown83
Be careful with blasting. You can drive dirt or other impurities into the surface and cause porosity in your welds.
MIG is more tolerant of dirty metal than TIG, but not much.
I use a pneumatic sander to clean the surface for either one before welding.
I have to agree with Hotrod46, if your good with mig then do it that way. I prefere tig only because its cleaner and i can manipulate it better , but mig is also nice to.
All have their place. I've used both on frames, as mentioned tig requires a lot more careful fitment of all the pieces but IMO leaves a great looking weld. Mig is much faster and done correctly plenty strong for a hot rod. As a standard rule around here, if it's going to go over 140 mph use a tig..... I've crashed (hard) with cages welded up with both mig and tig, none of them came in on me.....
I don't think this one will ever see 140 mph! I'm building it for cruisin not racing. Plus I'm using a flathead which for now is mostly stock, I probably am looking at 150 Horsepower max.
I use TIG because I have a nice new one, it's clean and doesn't leave spatter all over, Looks nice, easy to get good solid welds, I can weld almost any common material, no cleanup.....
You need a good fit, but no big deal. If you are "gap welding" with MIG you are kidding yourself on strength. It may get by because of shear volume of weld but if really tested it will not pass. You may be able to weld aluminum with practice with MIG but it will take time to get a good weld. Look at aluminum trailers. These guys do it all day every day so the welds are usually pretty good. MIG does a good job on mild steel but you need good fit and good wire for 4130 just as Tig plus you really have to work on penetration.
jmho
I think speed is also a factor, is it not? Mig is better when you are doing long passes and lots of them, but tig is a lot slower process, as I understand it.
I'm a little surprised the tig I got Dan hasn't been used more, but he is so comforable with his mig that he uses it almost exclusively. My buddy who owns the body shop bought the very same tig at the same time period, and he hasn't used his yet. He says he's waiting for Dan to teach him how.
Maybe when he starts on his body the tig will be used then.
Don
I've heard the same thing about TIG, that it is slow. Maybe I'll weld the center and rear crossmembers MIG, then take the frame to a buddy's to TIG the front crossmember, motor mounts, and shock mounts.
There isn't any doubt that TIG is slower more complicated and costly than MIG. It is also more difficult to master however you should be able to do pretty well if you can gas weld easily. You need to use both hands and one foot or the other, maybe an elbow for the pedal, maybe have someone else stand on the pedal( much harder) maybe just roll over on it. I always seem to be out of position with the tig but it isn't that hard. Plus I growl at anybody when they walk on my cables. You need a good helmet and an auto dark is nice for most applications. I still use my dedicated darks however. Just old fashioned but I hate getting buzzed when you block the light sensor.
if you are playing bet your life then it is tig for me . not hard to use and they have thumd wheel on the torch body no need for the foot pedal use to do all my work with mig .now all my work i use my tig
I went to the thumb control, too. Still put the foot pedal on for bench welding, but I use the thumb control for out of position welding....
It's a matter of preference as to thumb or foot pedals. My experience has been the same as yours...foot pedal for bench and thumb for out of position. When I learned to TIG I had neither, it was set your amperage and go :)Quote:
Originally Posted by Dave Severson
yep had a snap on that was like that .then had a old murtrain welder like a big old miller that was foot pedal not good for over head under a car try running the pedal with the side of your foot or prop it up with a heavy jack stand fun:3dSMILE: the new welder has thumb silde i just do not care of the pedal at all now .a friend talk me into the thumb control he build air frames took some time but like it even when sitting and welding on the welding table i block up my arms use a C clamp block of wood any thing that helps for them long welds that are up off the table like headder tubsQuote:
Originally Posted by 53fatfndr
personally i like tig better, much stronger and can control your weld much better, also tig in some cases no filler metal is needed , also a good tig rig you can weld virtually any metal, also on tig if it has to hold any kind of pressure you must tig it, mig does not seal very well, always a leak if you mig. but mig is wayyyyyyyy faster
bottom line is this. 70,80,90k tensile strength in the filler applied under the correct parameter conditions does not change in respect to which process you use. This is why in the "old days" they got away with brazing and gas welding. 90,000 does not change if it is by stick, mig, tig or torch. the key is in the filler and how careful you are to get near perfect conditions.
angle, arc length, machine settings, metal prep, grinding tacks, buffing off slag between passes and tie ins etc.
I used both when I built my chassis. I used the mig to weld in the boxing plates. This was much faster than using the tig, and the mig allowed me to use 18 gauge shims to create a gap to fill with weld before grinding the weld. I use tig for all crossmembers and brackets because of the nice neat appearance of the weld. The tig is excellent for this type of welding where appearance is important. The tig also has great weld penetration when used correctly. The tig welding process is by far the most difficult to master. Barry Lobeck's welder and Carl Fjiastadt of the Deuce Frame Company are great examples of what quality welds are possible with tig. They are truly artist at tig welding!
every thing has a place i use tig now more then any thing but i still use mig but not much .i can run ac/dc arc welding rod with my tig welding machine and i run more arc rod in the last year then the mig for iron welding and did a brick mold that had much wear and was over 2 thick wear steel that had to be filled with wear filler rod run 1/4 rod and filled it up so knowing what works the best for the job. it is nice to have options .as for tig being hard i think it is easy to use not hard at all if you ever gas welded you can tig that is all we did alot of in school
those workds usually come either from a pipefitter, boilermaker or an ironworker, which is it june?Quote:
Originally Posted by threearmsinjune
Maybe a pipe fitter -Quote:
those workds usually come either from a pipefitter, boilermaker or an ironworker, which is it june?
But my guess is none of the above, a pipe welder or inspector would mention grinding tacks . . . in order to get a 100% penetration root pass.
Since he said 'they' - I'm leaning towards inspector.