Before I commit, I though I would ask. I'm working on my rear end pan hard bar setup. I'm looking into TIG welding the panhard link directly to the axle pinion housing. The axle is a Eaton axle out of a Blue Bird bus. I believe the housing is cast iron, but I could be wrong since I dont know how to really tell. I have never TIG welded to cast iron before, so this is all new. But I've read through the tech tips and I have some ideas. Do you think this is a good idea? Would this be structurally fine to support the forces placed on the housing? Thanks in advance for taking the time!!
Nope, the heat will cause internal stress cracks that will break with added loads. In order to properly weld it you would need to empty the axle housing and preheat, before welding. If the carrier housing is cast steel, you should be OK if properly prepared. My suggestion would be to remove the top 6 or so bolts and make a plate to bolts thru, then weld a plate horizontally just like the one you wish to weld in place. What are you building? Those 1/2" bolts holding the axle in place look questionable also. 1/2 would be fine for a normal 1/2 - 3/4 ton truck, but something that would have that axle should have at least 3/4" or more diameter U bolts.
Yes you can weld it, but if you want it to stay you need to add a brace that goes to the pinion and bolts to 3 or so of those bolts. i would also make a tab and bolt it to the one closest housing bolt. I would preheat it and run a 7018 for penetration. I weld stuff like that all the time
You would be better off welding with 7018 with a little pre heat and let it cool slowly. On our school busses with air bags I am having problems with welds breaking around the pumkin cover on the back side of the diff. There is a lot of stress around there. Hope my info helps.
This is why I asked! I saw a easy solution that I though might work? I thought his would be a good place to bounce it off. I think Im going to look into another option and used those housing bolts as a mount surface. Thanks Again! My build is a 36 chevy Dually. I like the old split rim style found on dump trucks.
After seeing what you are building, I think I'd go with a heavy duty bolt on bracket -pick up at least the top three bolts where the pumkin bolts in and all six bolts around the pinion. Might even consider replacing some of the bolts with grade 8 studs. This would be stronger than welding onto the cast and completely removable for repair or modifications.
Do not weld on the housing. even if you learn how. If I were you I would not use a short Panhard bar especially if there will be some bump and droop (rear end vertical travel). If you must have a P bar make it at least 3/4 of the housing width but you might not be able to package it the way the narrow frame is. If I were you I would do a y-bar fron the top center of the housing forward to the frame rails. Use a 5/8" rod end in double shear on the top of the housing. Better yet would be a y-bar below the housing using a horizontal rod end. This will lower the roll center, and the car might have better drivability. Have fun.
I have welded broken ears on hog heads with TIG but there is no shear forces in the part like you will have. TIG welding cast iron works awesome if the casting is not full of dirt. You'll know it as soon as the metal becomes moltent beacuse the dirt will float throughout the puddle and crater or volcano when the torch is throttled back. I use a high nickel stick rod and beat the flux off of it. Then buff it up with a scotch brite. You MUST preheat it. Different people will say different temperature but my tempel sticks only go to 650F and that's were I go. Wrapping in fiberglass blankets afterwards controls the cool down more evenly than without. The cool thing is that the TIG torch is just the tool to induce the heat to get the metal moltent and the rod will flow in like butter melting. A little practice and you can do a fine job but not for high stress areas. Oh, success on welding ears is about 95% good. The other 5% is now yard art, a pot for the wife's flowers. I'm a good welder and I have the scars to prove it. Flying A
Why would you want to weld to the housing? Make a strong bracket and bolt it to the housing. If you try and weld it you are asking for a lot of trouble. I am not guessing on this.--TV
I see lots of bolts there on the center-section and the pinion support that can be utilized to bolt a bracket on. Just make a mount that spans the area between the three top center-section bolts to the top two-three pinion support bolts. No trancendental metal welding miricale required.
What I have seen above about welding cast Iron is true, needs to be pre-heated, I take it to 475, weld with nickel rod then re-heat back to 475 then burry it in a can of vermiculite (yes the flower garden stuff) with a lid. This process will take about 24 to 36 hours to cool the iron and help prevent stress cracks from forming. Another thing to think about is when you weld cast iron engine blocks, due to the heat involved all critical existing machining has to be trued, decks, crank and cam centerlines, and bores. I would say the same would have to be done to the gear housing. I would NEVER weld a life or death suspension part to a cast iron rear axle pumpkin. Just my opinion. <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
Um, any room on the axle housing, the cast steel, or stamped steel part??? Weld you Panhard rod doo-dad on the back side, or a Watts Linkage setup....
Don't want this to sound negative, but you've got a much broader problem than just welding to cast iron. The sprung to unsprung ratios of your suspension/chassis are so out of proportion that no suspension is going to work anyway. Not likely to matter to you based on what I see, but just thought I'd throw it out there for consideration so you don't end up with a suspension that doesn't function. Bob
Build a bracket to bolt on it will be cleaner in long run THA WILL BE ONE SIC BUILD!!!!!!!! Keep us posted
I knew this was the right place to ask! I think I'm going to drop the whole welding the bracket to the housing. Instead I'm going to need to figure out a second solution. I like the Y-Bar setup, and the Watts Linkage setup is cool. I'm going to take a second look at the pan hard bar with the use of a bracket instead of welding directly to the housing! Thanks Again! I appreciate everyone's thoughts and ideas!
nobody has given you any shit about the rat rod your building? Not on topic here and if you did a search this has all been covered before. At least you did an intro.....
Make a steel ring that goes aroung the pinion and use all six bolts, exstend it out and up then run your panhard bar to the frame, looks like it would be 20 or so inches and that would be plenty long for your limited travel. This is where dirt modifieds run theirs and it is shaped like a J hence the name J BAR.
I think that housing is cast steel... you shouldn't have any problem welding it... But how the hell are you going to gear that thing? You're mating a 5,000 rpm engine to a rear axle/wheel combo designed for 2100 rpm's... IF you can get the darn thing moving you'll be in first gear until 90 mph... As was mentioned the unsprung weight of the axles will force you to have a suspension stiffer than anything that frame can handle... you'd be better off building it on a big truck frame...but unless you have air ride it will ride like crap, I believe. BTW... those aren't "split rims" on the drive axle...they are "Dayton" wheels...more often called "wagon wheels"...the fronts, of course, are split rim tube type wheels. Good luck...you're gonna need it.
The Jalopy Journal
