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spaco spaco is offline
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Default babbitting - sooting the shaft, drilling the core for 'excessflow', gasoline stove pump cups?

Yup. A 1/16" hole will be just fine. Melted babbit can flow through
some pretty small places, and FAST! Try some to see for yourself.

It's not so much the "clearance' that you get with the soot, its keeping
the babbit from sticking to the shaft that's the big deal.

I don't know what an "electric torch" is, but it doesn't look to me that
you need that much heat. Getting the parts up to 300 degrees F or so
should be plenty. Most of that heat is needed to make certain that ALL
the moisture is gone.

For that small amount of babbit, why not just melt it with your
oxyacetylene torch and don't mess with the gasoline stove.
To get to the correct temperature, we use a pine stick as a tester.
when the metal is hot enough to pour, the pine stick will turn brown
immediately when inserted into the melted babbit and the stick will "buzz".

Make sure you've got a good seal at the "bottom" of the pour. The
babbit is heavy, and you'll be pouring from quite a ways above.

I probably don't need to tell you this, but make sure you and any
helpers have full face shields and heat/splash protective gear.

We once did a babbit pour where everyone "knew" the rules, but the part
had a tiny bit of grease stuck in a corner and it turned to a gas
immmediately, spraying babbit all over, including some that stuck to the
roof, 15 feet above.

Pete Stanaitis
---------------------

dave wrote:

I'm planning on doing a 'somewhat strange' babbitt pour soon.

couple of quick questions:

I need to pour the babbitt bearing around a 1.000 diam round cold-rolled
shaft. the shaft'll be dead vertical during the pour. the steel thing
I'm pouring the babbitt INTO is actually the center of this steel reel,
see the last six images on this page

http://machines.awardspace.com/6-4_SO-cord/

this procedure isn't gonna allow me lots of room to 'see down into the
reel core' during the pour, *BUT* I want the babbitt to ONLY go up as
high as a certain level INSIDE the reel core (about one-third up the
'fluted side' of the reel core, to be exact. best illustrated in this pic

http://machines.awardspace.com/6-4_S...os/photo5.html


so, plan is to drill a small hole INTO the side of the reel 'core' where
I want the 'top' of the pour to end, hoping the excess babbitt will just
'run out' through the hole.

question: how small CAN the hole BE? would a sixteenth diameter do the
job? (the whole dealie, reel core and shaft within and all, will be
heated for a solid half-hour with an electric torch immediately before
the pour, to 'help the flow')

and, regarding sooting the shaft: assume I do a nice job of sooting the
shaft with my oxi-acet, will the soot ALONE give me enough clearance to
be able to turn and lift the reel OFF the shaft after the pour? if
neccessary, I'll be honing out the babbitt a tiny bit after the pour
with a brake cyl hone...

anybody know a good source for those hand-pumped gasoline stove "leather
packings" that go in the pump? (the thing that'd be called a 'brake cup'
if you were doing a car brake repair). maybe it's called a leather pump
cup?

thanks guys

toolie

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