Hi everyone I was wondering if someone could help me? I want too weld some brackets on my rear-end axle tubes , (mig) weld. I don't want to put too much heat on them (warp) I have a Miller 150 machine I have been using to build a chassis. Any info would be great. Dennis.
some tell you to jig it all so it doesnt warp, you'll robably get 10 different answers. Personally, I have done 10 or 12 all assembled and it hasnt hurt them. I use really hot bursts with tons of time to let it cool. Go from front to back side of each bracked in the same spot so it pulls against both welds as it cools.
if the housing is all assembled how would you know that it's still straight or was straight to begin with? the best way is to check it for straight before and weld it how ever you choose and straighten if nessary after. By doing 360 degree welds you shouldn't have an issue. I usually find that just putting perches on doesn't do any damage.
28abone its easier to warp axle tubes than most people think it is !! first get some scrap pieces same thickness as your bracket and axle tube[or as close as u can and do some test welds to get the welder set up right [limited weld surface on the brackets and tube are not the place to set up your welder] after looking at your photo i realize u already know that [sorry] tig welding is best for this type of weld because you can control the heat and heat area much more than mig. a good mig weld reqiures a "short run" normaly to get good weld bite into the metals and that is where people f-up !! starting at bead and go half way around the tube first pass ,that much heat will pull the tube towards the weld or heat source. if u take a piece of sq. tube and lay it flat on bench then take a nother piece of sq. tube set it on top at 90 degrees [to form a T] and completely weld it up no cooling or moving around it is going to pull[or bow ]the the piece laid flat on table. same with welding the axle tube if u are welding say shock or a panard mount less welding less heat. alot of 4-bar and ladder bar brackets are a 360 degree around the tube to help stop this problem[u cut them at center of tube opening to get on axle tube and weld together] any way short beads and moving a round letting each short bead cool then another short bead elsewere and let cool is best. if you are good with your mig and have at least .035 wire u can pulse weld [or stitich weld ] also.but you must be sure of the bite or penitation .good tig welds look like a" stack of dimes" with a half overlap you can do this with a mig but evrything HAS to be right![material clean,welder setting right, gas ajustment and technic] you look like you have the skill level the tube frame looks great i hope i helped will ck back if u have a question about my rambling THE MAERSTO
small full penetration welds..stop..cool down...move,.. small full penetration weld..stop cool down..repeat until job is done
In cases where you're going to be having to narrow the axle housing, weld all your brackets on first, then narrow it. When they put it in the jig to weld on the new housing ends, it will hold the housing ends in the right spot even if you have warped the tubes somewhat welding your brackets on. I made homemade 4-bar brackets that wrap around the axle tubes 360 degrees. That seems less likely to warp an axle tube when you're welding all the way around it, and you make short welds (about an inch at a time) back and forth front to back, allowing a lot of time to cool in between welds. But when the brackets wrap all the way around, you have to use them on an axle housing that you can chop the housing ends off of first. The brackets that are only on one side of the tube are probably more likely to warp the axle tube if you get too big of an area of the tube hot at once. Take time in between welds. If you weld with fat long beads on one side of tube without taking a break and get the whole side of the tube glowing red, it will shrink in those areas and pull the tube a little crooked when it cools down.
I saved this thread awile back, some very good info here http://www.jalopyjournal.com/forum/showthread.php?t=249023
Yea, what the hell kind of chassis is that. It sure is wide. Overbuilt for sure. Monster truck maybe?
we and ,or, i have never used a jig for welding brackets for shocks, panard bar mounts or any type of 4 bar ladder bar or radius rods ,didnt see the need ,if you just take a little time welding and dont race throught it, but i have seen new 9" rear ends that have been over welded and have bearing failers in a couple thousand miles. its along the same lines as frame benchs if u set up take measurements and hold those measurements there is so much variance in frame work u dont need t jig up a frame. working with hot rod chassie body combs. it really holds true. THE MAESTRO
When we ran dirt track we used to put in or take out toe on the rear axle housing by heating it and cooling it. Once you do it a few times you kind of get the hang of it and know how much heat to use. I have also seen people weld so much stuff on a axle the one side was out 3/16 and the other 1/4 the other way. just be carefull take you time and do a little at a time let it cool move to the next side and do it again. good luck
an old racer told me this once and i've used it for years,so take it for what it's worth, wrap a wet shop rag around the axel housing on both sides of where your welding to act as a heat sink. he was pretty well respected,so i sorta believed in what he was saying.again for what it's worth..............................
I have never had a problem with welding a bracket onto one side only of an axle tube, but then again, all the rearends that I have ever used were from donor cars that had a zillion miles on them already, and had a lot of wear on them. This meant that probably if the axle tube did bend a bit, there was enough slop in all the clearances that a slight bend would go unnoticed. However, if you are concerned, then make your brackets like this 3D model I just created. Make it a full 360 degree bracket, then split it as shown to get it over the axle tube, then tack it back together. Position it correctly, then weld all the way around a full 360 degrees in short "bursts" alternating from side to side as you weld. The thing that causes axle tubes to bend is a lot of welding and concentrated heat on one side of the tube only. With a bracket like this, the heat is equalized all the way around the tube, so bending will be kept to an absolute minimum.---Brian
WOW this is a thread for supposed guru's versus I did it this way -LOL I have modified probably well over a 100 without a jig and after the job is finished check it for accuracy and no problems. When I do a full length back brace on a 9 inch I tack on each end and middle then simply go about an inch on one side then the other then middle. When welding flange ends on I do use a jig but still rotate my welds. A square,leavel and plum bob will tell you where your at as to straight and most guys have these in their shop
Here is a way of checking for warpage. Put the thing together and put wheels on it. Block the wheels and rotate the housing. Use an indicator or put something near the top of the wheels and look for movement or camber change. No Change=OK
Weld an inch of bracket per tube. Cool for half an hour, hit it with another inch per tube, repeat til they're done. You're kind of overthinking this whole thing. Look how shoddy 70s/80s OEM axle brackets are and you'll become a lot more comfortable.
I think the most important part is to be patient. Welding in the same area and allowing the heat to build up is the biggest problem. Move around from side to side allowing plenty of time for the weld to cool. It can take a couple of hours for 30 minutes of welding with all the cooling time in between. I've done an ass load over the last 40 years for me and my friends and never had a problem.
On a side note, we make large truck axles, Peterbilt, Kenworth, etc. The axle housings (top and bottom) are pressed in a 200 ton press. Then they are welded together, then the pumpkin in welded on. The tube ends are friction welded (push onto the end, apply tons of force, rotate) As you can imagine, at this point it aint gunna be straight. It is placed in a straightener, spun to check out of round, stops at appropriate location, then "pressed" in just the right spot (this huge axle actually bends several inches) spun some more, pressed again, until it meets spec. Cool stuff to watch. Rich
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