Removing bearings from idle wheels

JG Custom Metal Works

JG Custom Metal Works

Joined
Nov 27, 2013
Messages
1,626
My bearings in the idle wheels on my KMG platten are bad and need replaced. They’re seized up bad. I know they’re bad because they get hot as hell when running the grinder and make a nasty sound. The wheels, bolt, and bearings get hot enough to instantly boil liquid when it hits the surface. Of course once I noticed this I stopped using them.

I did some searching on this forum and also called Beaumont and they said to use a bunch from the other side. That ain’t happening. There’s no where for the punch to rest on and they are seized on there way too bad. I bought a bearing removal tool with a slide hammer yesterday from Harbor Freight yesterday and I can’t even get them out with that. It’s crazy.

I have the wheels in the freezer now and was gonna try the bearing remover again in a little bit. If that doesn’t work I’m gonna try a heat gun or torch. Beaumont told me I could sent them back and they’d fix them, but I’d rather do it myself and not have my grinder down for days on end. Plus, I already bought the bearings.

Any ideas? I’d greatly appreciate the help.
 
aluminum is pretty cheap. if you have a lathe just make some new ones :)
 
Aluminum's coefficient of thermal expansion is roughly twice that of steel. Heating the wheel to 400F will increase the diameter of the bearing pocket .005" while the steel bearing race should only increase .003" at the same temp.

Put them in the freezer, then heat from the outside of the wheel to keep the race cool as the wheel warms up. Then pop them out with your slide hammer.
 
I don’t know what your bearing removal tool looks like, but Snap-On sells a variety of sizes of blind hole bearing pullers. They attach to a slide hammer. Liquid Nitrogen or dry ice may produce more shrinkage than a freezer. Kroil is a pretty good lubricant for stuck stuff. Good luck.
 
i am sure someone will give a tried and true answer, but if it was me i would put a flathead screwdriver through the back and catch the back edge of the one i want removed at an angle, and try to tap it out. i would hammer around in different spots, because hammering in one spot would drive it out unevenly and probably wedge in there tighter.
 
JG Custom Metal Works said:
My bearings in the idle wheels on my KMG platten are bad and need replaced. They’re seized up bad. I know they’re bad because they get hot as hell when running the grinder and make a nasty sound. The wheels, bolt, and bearings get hot enough to instantly boil liquid when it hits the surface. Of course once I noticed this I stopped using them.

I did some searching on this forum and also called Beaumont and they said to use a bunch from the other side. That ain’t happening. There’s no where for the punch to rest on and they are seized on there way too bad. I bought a bearing removal tool with a slide hammer yesterday from Harbor Freight yesterday and I can’t even get them out with that. It’s crazy.

I have the wheels in the freezer now and was gonna try the bearing remover again in a little bit. If that doesn’t work I’m gonna try a heat gun or torch. Beaumont told me I could sent them back and they’d fix them, but I’d rather do it myself and not have my grinder down for days on end. Plus, I already bought the bearings.

Any ideas? I’d greatly appreciate the help.
Click to expand...

I have maybe 50 different tool for bearing removal in my shop but in you case I don t know how they a mount so no advice ...But at the end of the day , when even 50 puller don t help , Dremel with small cutting disk is my tool of choice
 
kuraki said:
Aluminum's coefficient of thermal expansion is roughly twice that of steel. Heating the wheel to 400F will increase the diameter of the bearing pocket .005" while the steel bearing race should only increase .003" at the same temp.

Put them in the freezer, then heat from the outside of the wheel to keep the race cool as the wheel warms up. Then pop them out with your slide hammer.
Click to expand...
Kuraki was right , maybe you should try to heat wheel and than hit it on some flat wood with opening large then Dia. of bearing .. maybe bearing will go out ? Try both side ...if one come out probably would be easy to take out other one ?
 
I saw picture on net , but can t see what I need . Did bearing have tube between them or not ? If they have , some hard round steel will catch on bearing ....If not , take some hard round steel , cut flat and hit with hammer behind bearing /I mean start hitting in aluminium / You will little damaged inside but I don t see problem with that .Do that on two opposite side ..... ??? Make sence ?
 
Got them out. I pulled out the heat gun and heated it on high for around 30 seconds. Then put the bearing puller on, heated up a little again, to compensate for the heat loss from time and the cold bearing removal tool contacting it. I didn’t want to heat it too much with the bearing removal tool in it because it might have ruined the tools temper. Tightened it down and hammered the hell out of it. It still took a good amount of effort, but they came out.

So, I need to press in my new bearings now. Any advice? I was thinking maybe freeze the bearings, heat the wheels, and then press them in with a one ton arbor press. I might put a small piece of flat stock in between bearing and the ram so the pressure is evenly applied. I know it’s not good to use and lubrication with sealed bearings, but would it be appropriate when pressing them in? Maybe some white lithium grease?

Thanks a bunch for taking the time to respond everyone. I really appreciate it.
 
JG Custom Metal Works said:
So, I need to press in my new bearings now. Any advice? I was thinking maybe freeze the bearings, heat the wheels, and then press them in with a one ton arbor press. I might put a small piece of flat stock in between bearing and the ram so the pressure is evenly applied. I know it’s not good to use and lubrication with sealed bearings, but would it be appropriate when pressing them in? Maybe some white lithium grease?

Thanks a bunch for taking the time to respond everyone. I really appreciate it.
Click to expand...
Well done :thumbsup: That is best way , and if tolerance is right they should go inside easy .But before you start , clean well inside of housing.....you can use grease when pressing , can help but can t make damage :)
 
Sounds like you have it well under way...
If its real tight, A smear of grease in the bore may help.
But I would just start out with a very clean bore, heat the wheel, freeze the bearing,& work quickly. It might even drop right in...
Of course if you have to press, only apply force to its outer race.
 
Dry ice / acetone will shrink the bearing, a good blast from a can of dust off gets them pretty cold too. That's what I used to get a set out once. I figured the cold concentrated on the bearing was more effective.
 
SBuzek said:
A good way to press them in is use a socket the same size as the outer race and your arbor press.
Click to expand...

That’s a good idea. I’m gonna use that.

I’m gonna give it a go tonight and if they won’t go I’ll try liquid nitrogen tomorrow. I need to refill my dewar anyway. They should be alright in LN shouldn’t they?

Thanks again guys.
 
JG Custom Metal Works said:
That’s a good idea. I’m gonna use that.

I’m gonna give it a go tonight and if they won’t go I’ll try liquid nitrogen tomorrow. I need to refill my dewar anyway. They should be alright in LN shouldn’t they?

Thanks again guys.
Click to expand...
Don t do that .Except if in bearing you have some DuPont grease for NASA space shuttle :) Put them in a regular freezer . . . that's enough .
 
I was able to get them in last night dry, with no heat. I will say Stan’s advice for using the socket worked great for multiple reasons. There is a sharft that runs inside the wheel that needs to be aligned with the two bearings. The first time I pressed the second one in, I pressed it in part way so I could check and make sure it was still lined up. It wasn’t. So I popped one of the bearings out and tried to figure out how I would keep it from moving inside the wheel while I put a punch of pressure on things. Finally I figured out that I could just run the capture bolt(that connects it to the machine) through the whole operation and the part that stuck up through the top would just run into the socket body when I pressed down. Perfect! FYI my arbor press has a channel where the base is so that the bolt was able to sit lower than the wheel. Otherwise it would have been too proud of the wheel. If this doesn’t make sense, I can take a pic.

I really hate starting threads on here unless I have to, but I couldn’t find anything else on here addressing the issue. I appreciate the help.

Oh and in an effort to help future people who may come across this thread looking for help, I’ll link the bearing puller I bought below. Also, these bearings are called “blind bearings” btw. Once I found that out I searched “how to remove blind bearings” on google/YouTube and found videos of people using the slide hammer bearing puller. Just remember HEAT IS THE KEY when removing seized up bearings like these. The bearing puller alone wouldn’t work for me. Again, I used a cheap Harbor Freight heat gun on high setting for 30 seconds,mscrewed on the bearing puller, heated for 15 more seconds, and started hammering. Bingo.

Slide hammer bearing puller:
https://www.harborfreight.com/slide-hammer-and-bearing-puller-set-5-pc-62601.html

To be honest, the quality of the tool wasn’t that great. The collet that expands under the bearing bent slightly during use. That could have been from me not heating the bearing up first though. I think Walmart online sells one for $42 that might be higher quality. Who knows, I haven’t used it. Good luck
 
You must log in or register to reply here.
Back
Top