# How to press bearings on shaft?



## Pete Q (Apr 18, 2010)

OK here is the problem: I have to replace drive shaft bearings on new-to-me 60's model IH balanced sickle mower. The bearings fit the shaft very tightly (they require a press or some skilled hammering to slide them on the shaft). The problem is that the bearings need to be pressed onto the shaft from opposite directions and there is nothing to hold the shaft in place while doing this. Ideally I would need some kind of press that can press from both directions simultaneously. What kind of tricks are there to get this done? I imagine the pro machine shops use some kind of hydraulic tool for this, but I don't want to take the entire implement to a machine shop just to get a couple of bearings pressed onto a shaft. I have been looking for a very deep reach metal clamp that I could use as a manual press, but no luck finding one here in local stores. 

If you happen to understand my poor explanation of the problem and happen to have an idea how to get this done, please tell.


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## ace admirer (Oct 5, 2005)

are they radial or tapered bearings? does the shaft have a shoulder between the bearings? 
are the old bearings off the shaft?

when i lack facilities for interference fit bearings on a shaft, i use a 60 watt bulb to gently heat (expand) the bearing and install with a gloved hand.


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## ace admirer (Oct 5, 2005)

are they radial or tapered bearings? does the shaft have a shoulder between the bearings? 
are the old bearings off the shaft?

when i lack facilities for interference fit bearings on a shaft, i use a 60 watt bulb to gently heat (expand) the bearing and install with a gloved hand.


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## Ozarks Tom (May 27, 2011)

I've heated bearings in an oil bath, and turned press fit into slide on.


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## Pete Q (Apr 18, 2010)

Ozarks Tom said:


> I've heated bearings in an oil bath, and turned press fit into slide on.


I have heard about that but did not think they would enlargen so much that would still not need quite bit of pressing. If you say it works I will try it tonight.



ace admirer said:


> are they radial or tapered bearings? does the shaft have a shoulder between the bearings?
> are the old bearings off the shaft?
> 
> when i lack facilities for interference fit bearings on a shaft, i use a 60 watt bulb to gently heat (expand) the bearing and install with a gloved hand.


These are radial bearings. I got the old bearings off with a standard bearing puller, and actually I got one new bearing pressed on as I could do that with shaft in my work bench, but now I need to press the second bearing on so that the shaft is in the housing. There are no shoulders on shaft. 

The lamp is good idea for heating too, maybe try that first and then warm oil bath next if it does not work.

Thanks for ideas so far!


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## Darren (May 10, 2002)

Another trick is to use dry ice to shrink the shaft. Buy it from a welding gas supplier. I've used that to install metal cased seals. Don't forget to wear gloves. The dry ice temp is about -100 degrees Fahrenheit.


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## OkieDavid (Jan 15, 2007)

Heat the bearing and chill the shaft somehow (dry ice, ice chest full of ice water etc..)


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## farminghandyman (Mar 4, 2005)

20 Ton Shop Press - Hydraulic Shop Presses on Sale

this is what I suggest,

press on the race that is being pressed on some times a pipe works well, or a socket 

there are smaller presses but I would not recommend a smaller unit, you may not need a 20 ton, but there are times one does,

and the cost of the two are not that much different, 

depending on the situation one may be able to make a frame out of some all thread, (rod that is threaded) get two 3/4" or 1" rods and nuts, and two plates one to go on each side of the unit, (shaft) and a plate on the other side for a Jack, and if it has to go on a deep shaft a section of pipe to press the bearing and the jack on the pipe, 

if you have enough hands one may be able to tighten both rods (nuts) equally add some extra washers for easer turning, (they will work like bearings), 

if one has two trees the right space apart one could possibly set up a jack and press it on, 

but the easiest way is the shop press, and it may only cost a few dollars to take to a shop and have it done, 

(not really sure of the drive shaft deal) but there are special tools for bearings on car axles that extend the reach of the press or so one does not have to have it spread 3 feet apart, that possibly could help in your situation, 

there is what is called a bearing separator or splitter (basically two half's that bolt together) that support the back of a bearing and one can thread rods into the separator, to pull with on a bearing puller, Bearing Splitter & Large Bearing Separator (not that I am a big fan of harbor freight but they do have some low cost items, that are fair for the dollar, 

this video below may work as well, simular in design in the bearing puller extenders for a car axles
[ame=http://www.youtube.com/watch?v=kYHFCJy6DPw]$5 Bearing Separator - YouTube[/ame]

this is some what like I was sugesting but using all thread, [ame]http://www.youtube.com/watch?v=Uab9VncBIUg[/ame] here is a comercial version or close, http://munstertoolco.ie/sykes-pickavant-09310000-external-separator-kit.html

a picture of the problem would help to get a better and clearer answer,


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## ace admirer (Oct 5, 2005)

yeah, make sure the shaft is very clean.polished clean and no burrs. watch the heat, a 60 watt bulb with a bearing sitting on it heats pretty fast. if the bearing is sealed and factory lubricated, about 400 degrees is as hot as you want to go. you have to be pretty rapid when assembling. 

if oil bath is used, watch for flames, spilling hot oil and have the proper tools for retrieving the bearing from the depths of the container, watch getting the gloves soaked in the hot oil. all of this is why oil is not used in industries now. we use conduction contact headers and induction heaters.


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## Pete Q (Apr 18, 2010)

ace admirer said:


> yeah, make sure the shaft is very clean.polished clean and no burrs. watch the heat, a 60 watt bulb with a bearing sitting on it heats pretty fast. if the bearing is sealed and factory lubricated, about 400 degrees is as hot as you want to go. you have to be pretty rapid when assembling.
> 
> if oil bath is used, watch for flames, spilling hot oil and have the proper tools for retrieving the bearing from the depths of the container, watch getting the gloves soaked in the hot oil. all of this is why oil is not used in industries now. we use conduction contact headers and induction heaters.


It worked! The oil bath ended up being easier first try so I just heated up a half pint of oil on an electric burner I have in barn anyway, so no risk with flames. I also realized that the shaft needs to be clean of burrs to reduce friction so I used fine sand paper to polish it a bit. The hot bearing was still slightly tight but I could press it on with a pipe and pushing the opposite end of the shaft against my thigh. Ended up with perfect fit and a very tight bearing after cooling down. 

Great advice - thanks alot to all of you, ace admirer, Darren, Ozark Tom, OkieDavid and farminghandyman!


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## Pete Q (Apr 18, 2010)

farminghandyman said:


> 20 Ton Shop Press - Hydraulic Shop Presses on Sale
> 
> this is what I suggest,
> 
> ...



Wow this is a motherload of great advice, farminghandyman. The hot oil bath was all I needed this time after all, but I will save this post for future reference. Thanks!


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