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lastditch
10-08-2002, 11:56 AM
Since we have quite a diverse talent pool on this sight how about this one.

Anyone have plans or specs for making a bearing heater for installing bearing the easy way?
From what I remember of them there is not much to them for parts. Looks like half of a transformer
I have access to lamination material, so what else does one need?

Forrest Addy
10-08-2002, 01:48 PM
Why bother. My bearing heater is an old fondue pot. I usually heat them dry but if I have several to mount I heat them in oil.

Rotate
10-08-2002, 05:33 PM
Bearing heater is essentially a transformer where bearing rings become the secondary winding (shorted). This method of heating bearings is very good because it's very efficient and there is little chance of lubrication leaving the seal or contemination entering the race.

It shouldn't be difficult to make one, however you will need to split the core so that the bearing can be slipped in.

Good luck.


Albert

rbregn
10-08-2002, 08:27 PM
I use a "Fry Daddy" . It was my wifes, until I put motor oil in it. For some reason she didn't want it back for cooking french fries in it. So now I have another tool in my garage!

motorworks
10-08-2002, 08:37 PM
Hi
A desk lamp turned up with a 25 watt chanderlier bulb.Place the bearing on the bulb,cover with tin foil and in ~ 5-10 mins
the bearing will be hot enough.
Don't leave on too long and be careful as the bearing can get very hot.Welding gloves come in handy.
e

charlie coghill
10-08-2002, 10:11 PM
Hi Guys;

I know I will be crucified for this one. I have a electric stove burner that I plug into the welding outlet. The burner that I have has a place where the burner fastened to the stove, this is where I connected the ground wire. Place a couple of bricks on a welding table or a noncombustable surface,place the burner on the bricks and the bearing on the burner. You will have to watch the temp and use welding gloves as the bearing can get real hot. If fact it can get too hot.

Charlie.

[This message has been edited by charlie coghill (edited 10-08-2002).]

lastditch
10-09-2002, 07:10 PM
Thanks for the ideas on the bearing heater.
I use hot oil bath right now BUT with two 4 year olds and a 7 year old checking my work I need a safer way.
After reading the recent homemade themocouple post I went to the http://www.omega.com/ web
sight and seen they have the electric strip heaters among various other electric heating elements fairly reasonable. I got some strip heaters laying around I will have to give that a try have to see the wattage on mine. I will post if they work out.
Has anyone tried these yet?

Thrud
10-10-2002, 02:17 AM
lastditch:
I have only used the crude methods in emergencies. Timken makes a small CPU controlled bearing heater that is cheap insurance if you do lots of bearings - it will never over heat them. Overheating a new bearing when installing is one of the major reasons for premature failures. Try to keep it under 180*F to minimize damage. Always check with the bearing house or the manufacturer for proper instructions. Measure twice, cut once.

Hellbender
10-11-2002, 10:43 AM
I just use an electric hotplate, welding gloves and a 180deg. temp. crayon, heat on 1 side (smaller) a little while, then flip (a pancake spatula works good http://bbs.homeshopmachinist.net//biggrin.gif) over and heat until the crayon marks it.

My grandpa used water drops on top until it evaporated (but don't wait til it sizzels), not very scientific, but I never remember one failing.

HB

------------------
NRA Lifetime Member

Ragarsed Raglan
10-11-2002, 12:12 PM
I don't like to heat bearings, I like to freeze the shaft! We use Liquid N^2 at work for valve seat inserts (they are a dovetail fit in our engines), and for valve guides. So a super low temp thermos flask comes in handy for the carry out!

It can even be used for installing the outer ring. I used some aerosol expanding polystyrene GP filler sealer to insulate a bread tin within a bigger bread tin to give me an open bath of the stuff.

Gov't health warning: beware, this is dangerous stuff - not for the faint hearted.

RR

trap
10-12-2002, 10:24 PM
Most of the time I use a press and drivers to install bearings ...... until something goes into aluminum. Then it's time to get out bearing heaters and/or the cold stuff. Sometimes I will put an aluminum housing in an oven to install or remove races / bearings.

To heat a bearing just to install it on a shaft sometimes causes a lot of problems if it seizes to the shaft before it bottoms out.