I've gone through the search threads and am still up in the air as to wether to cut and splice two different pitman arms together in this case a dodge top to a 36-37 Ford bottom. I would have a pro welder do the knitting as I just have a small mig. Any opinions before I send the time and geta's?
I did that with a '33 Willys grafted to a '32 Ford. The trick is to use as much of the individual arms as possible, then grind them flat on the mating surfaces so you have a good fit. When you weld them together, make sure you use a qualified(certified) welder to do the welding and weld them along the full length of each edge. If you do it right, you shouldn't have any problems.
This is in the tech archives. I would think the same process could be used for changing splines on one if there was enough meat left to weld to.
I disagree with HOT ROD 40 COUPE---Being a certified pipe welder since 1957, after grinding both FLAT ends, BEVEL EACH part 33 degree's, leave a 3/32 gap between both parts, preheat slightly & run your first (root) pass, turn over & run the next pass, now that your work is nice & hot, back off the amps a little, & continue to weld on each side, alternating back & forth as you weld up to surface, If you have access to LO-HY (low hydrogen) rod, fill remaining surface with it, otherwise finish with same type rod.---------------Don
Have seen several done buy a certified welder Parts were chamfered before welding to give most possible weld area. Sort of like this. Like Don Says
You GO, Don!!.......hey, you got time to do some lakes dumps for me this weekend? I need a certified welder......... CB
Do it! I would drill and pin it in the center though. I am assuming you are familiar with tig? I would recommend tig welding it for sure. My 60 year old plus hot rodder buddy just told me a story that he sawed two pinions apart and welded the two halves he needed with a pin in it back together and ran it for years in their olds gasser! This guy is a serious genius, i am lucky to know him. Dons advice is solid gold.
i agree with deuce daddy don except i would use tig weld.its a cleaner ,stronger weld. after welding ,let cool for 4 to 8 hours
The Model A Restoration series of books put out by MARC or MAFCA, I can't remember which, had an article about this. They recommended cutting each end to be welded with an "L" shaped stepped cut down the length of each part leaving a little extension step on each part that would fit together with the other parts end. I've tried to illustrate it with typing but the site won't show it properly. Basicly the two L shaped stepped ends are prepped to fit the two opposite shaped steps together for more cross sectional area in the weld. I hope you can visualize this.
I'm with Don on this one also... Tight fits are for ladies blue jeans. I'd also set it on an anvil and peen the hell out of the weld area as it cooled. Not hard, but swing that hammer until your arm is tired and the steel is cool enough to touch.. It's a metal thing... molecules and cracks while cooling kinda stuff... but trust me. JOE
I am working on my cowl steering now....I think you should clarify in your post you are not welding cast parts.....right?
http://www.jalopyjournal.com/forum/showthread.php?t=269720 I don't think a pin would be any advantage. For a round shaft that needs to be concentric, yes. But with a pitman arm it's only going to reduce the weld area.
I suppose it would depend on the style of pitman arm, im not too familiar with a 37 ford pitman arm. I like pinning things as much as i can when making a fit like this, just my thoughts.
I guess I didn't make myself clear. That's why I suggested he go to a certified welder, they would know to bevel. What I was referring to was the full length of each pitman arm as the mating surface so that you have a large overlap of material, the full length of each arm. Then bevel and weld.
It's not whether a part is cast or not. It is what metal a part is cast with. You will never find a "cast iron" part in a suspension or steering system. The question is it steel or iron. You won't find iron in any critical factory steering or suspension part. Cast iron is what engine blocks, sewage pipe and your grandmothers black frying skillet is made of. Steel is what gas pipes, steering components, I beam axles and sky scraper I beam frames are made of. Just because a part is cast does not mean it is inherently subject to cracking of unable to be welded safely. Iron is a natural element . Steel is a man made alloy.
Pitman arms would be forged steel, not cast iron. Why do you need to do this splicing in the first place? If you must weld it, I think the splined hub welded into a one piece arm would be the safest approach.
Very well put TOMMY. Cast (or forged) steel steering and suspension parts... especially the old stuff... is some of the best metal you could hope to weld. JOE
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