Getting the roll pins out is a real problem for replacing the planet
shafts with a special hardened and ground bolt/planet-shaft.
I think a hypodermic needle and high pressure oil might work.
Put the needle all they way down in the bottom and apply a shot
of high pressure oil to the needle. In theory it should pop out some
what.
I also thought about tapping it with a 2-56 tap.
Then there is supper glue and welding wire but you have to get all
the oil out first.
Here is another idea. Stick welding wire in and apply a lot of current.
The welding wire might then weld itself to the roll pin. Then pull it
out. This trick might work the best and is easy to try on the junk
planet carrier I have. Are you up for this test Ed?
Paul Lamar
Using the welding trick has real potential.
Insert the welding rod only into the roll pin about 1/16th of an inch.
This should reduce the possibility of the roll pin welding it self to
the planet carrier instead of the roll pin.
Something as simple as a 12 volt car battery should put out enough
current to weld the wire to the roll pin.
Paul Lamar
Here are some ideas from the Internet.
Take a small stick welding rod and knock off the flux at the end. Grind
it a bit so it'll go into the hole in the pin tight. Turn the amperage
all the way down on the welder. Hook the stinger to the rod and
gradually turn the amperage up, giving the pin time to heat up. You can
probably get a 1/8 pin red hot with 30-40 amps at most. Once its hot,
gradually reduce the amperage so it doesn't cool fast enough to
re-harden. At that point it should be fully annealed. It might come
right out, but if not it'll be soft enough to easily thread a hard screw
into it so you can get a slide hammer on it. It generally works much
better than a torch because it puts the heat exactly where you need it.
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Use some heavy putty or clay
Make a roll of it and keep pushing it in the drilled hole [at the blind
end of the pin].
Than give some blows on your small piston in the drilled hole and ad
some more putty if needed.
Putty or clay works better if there is some leaking
You can also drill a hole from the back of the casting or the side
But this is definitely the way to remove a pin out of a blind hole
Peter from Holland
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forget all the heating, beating and other crap and get an eighth inch
carbide ball burr
position control is important so you stay on center, but spin her up
use coolant and cut it out.
takes maybe 60 seconds
i have done several fuller transmission mainshaft rollpins in this
manner, shafts that have been scrapped because machine shops cannot get
those hard little bastards out.
at least the shops in this area can't get them out.
i use a dremel tool and plunge right into the little bugger, taking a bit
at a time, and use anything handy for coolant.
8 bucks for a burr and a minute is well worth the effort.
bob g
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Does it need to be welding rod? Would a piece of drill rod work?
This got me thinking (dangerous, I know): Assuming something besides
welding rod can be used, is there a way to tin the rod with silver
solder (or whatever), flux it up and have the rod solder itself to the
roll-pin as everything cools? Obviously, if you did it wrong you could
wind up silver soldering the roll-pin into the hole...
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I've had success just screwing a hardened drywall screw into the roll
pin and pulling it out with a slide hammer. Metalmunchr (above) adds
softening the pin for a good bite -- a great idea. In any case, might
try just the screw to start. In my case, there was enough bite to do the
job, even with a hard screw into a hard pin.
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... Does it need to be welding rod? Would a piece of drill rod work?...
A common nail would probably work just fine.
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