How would you do this?

My cousin-inlaw is working or restoring an old John Deere Tractor and came
to a point where he needs to make a part for a pushrod that cannot seem to
be found for love nor money, I'm sure ther are plenty out there somewhere
but right now he can't seem to locate one and wants to get the tractor back
together. Its not big, its a 2 inch long 3/4 inch diameter cylinder with a
hole on both ends but not through drilled. The one hole is drilled to
press fit on the push rod and the other has a semi sphericle bottom for a
cam socket. Looks like a simple lathe operation or even just a drill press
and the correct sized blank. My question is how would you make the semi
spherical bottom of the cam socket?? My thought is to drill is partially
out with a normal bit then grind a bit the have a semi circle profile to
finish it up and maybe lap it a bit with a ball bearing and some compound.
He is thiinking of drilling and finishing it up with a ball grind stone in
a drill press. My question is how was this done originallu and/or how
would you do it in a home shop.
Thanks
Bill
Reply to
Bill
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Bill wrote in news:Xns983B59AAFC004fredbarneybigmailbox@216.196.97.142:
Are you describing a lifter, aka cam follower? A picture would be most helpful. THe steel used in lifters is very hard.
Years ago, my father would rebuild old tractors and what he found was that manufacturers sometimes used parts from the auto industry. One particlar tractor he worked on required piston rings. He couldn't find a set as the company was defunct. After doing some checking he found that a set of rings for a Packard fit perfectly.
Reply to
R. Pierce Butler
Snippage
Ball end mill in a lathe?
ED
Reply to
ED
Drill as described, then finish with a ball end mill in the correct size. For a one-shot project you can chuck it into a drill press and do fine. If you have a lathe that would make centering it easier.
Reply to
Rex B
How you go about making this item isn't nearly as important as how hard it is when you're finished making it. If you get the heat treat wrong, or don't do it, the lifter (the item) will fail, taking the cam with it. You'll find yourself in worse condition than you are now. Assuming it is a lifter, and you have one as an example, be certain to duplicate the hardness. That means you may not be able to make a new one by hand, because it would require more equipment than you may have at your disposal. Typically, such items are centerless ground after heat treat.
Harold
Reply to
Harold and Susan Vordos
My rule of thumb is that if you have to ask, chances are you can't make it. If you have to ask but don't and you can't make it right, then you're either dumb or you're me :-).
There are groups of restorers all over for old tractors, particularly John Deeres. If it's really a lifter I would try to get in touch with the group close to me and see if anyone has one to buy. Alternately, I'd go looking on ebay.
Reply to
Tim Wescott
There are many sorts of pushrods on machinery. Is this an engine pushrod, or is it something like a brake or clutch linkage pushrod?
Reply to
Rex B
I'd use a radius-cutter tool.
LLoyd
Reply to
Lloyd E. Sponenburgh
May be a dumb question, but has he checked with a John Deere dealer? I have a 1936 BR and if I need parts I pick them up at the dealer. They had every part I needed when I restored my tractor, except the fenders! Greg
Reply to
Greg O
"Greg O" wrote in news: snipped-for-privacy@corp.supernews.com:
Not dumb but I'm not the one with tractor experience so I ASSumed since he said he couldn't find one he meant he'd exhausted his local contacts such as nearby dealers....I'm wondering if he actually meant, I can't find any squirled away in the barns/sheds/corncribs on the farm and no brother/father/inlaws have any they can find. Not that that means there might not be one around on one of the above farms, being that most of the farms in the family go back over a hundred years in the family and junk collects...
Bill
Reply to
Bill
Rex B wrote in news: snipped-for-privacy@corp.supernews.com:
Engine pushrod.
Bill
Reply to
Bill
"Harold and Susan Vordos" wrote in news:vUhNg.812$ snipped-for-privacy@newsreading01.news.tds.net:
Believe it or not hardness crossed my mind when we were discussing it but like I mentioned in another post he has the engine and tractor experience, I don't so I ASSumed he will take that in account....... If not I guess the tractor will be needing a new cam in the near future.... I do like the way the old stuff fits together and the mass of real iron its made from, seems like it would go no matter what breaks, just hammer it back in place and finish plowing. Kinda of a "File to Fit and Bang to adjust" type of machinery :)
Bill
Reply to
Bill
A radius turner would do great. I've been playing with one at school. Only have use it for convex so far but would do the same for concave. ...lew... If he's near Albuquerque I'd do it for him.
Reply to
Lew Hartswick

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