Powermatic PJ882 - Question on Byrd Cutter Head

[Dennis Peacock]

Greetings,
I have a PJ882 that I originally bought with a standard cutterhead in it. This year, I decided to upgrade from the standard cutterhead to the Byrd Shelix cutterhead. I ordered it from Byrd with new bearings already installed. The cutterhead change out went fine and without any trouble. Upon 1st run, it was quiet and cut really well. After about an hour of running, the bearings started making noise, louder and louder the more it ran. I contacted Byrd and they shipped me new bearings at no cost to me. I pulled the cutter head out, removed the noisy bearings and installed the new bearings. Once again, it ran smooth and quiet. After about 2 hours run time, I'm getting bearing noise again. What am I missing here? I've rebuilt and replaced bearings in almost every machine in my shop in the past 2 years and this one is the only one giving me continued bearing noise problems. What am I not getting right?

[Mike Kees]

Dennis ,I am sitting here baffled as well. If everything runs smooth with no extra vibration ,there does'nt seem to be a reason for the bearings to go that quickly. Something is wrong. How do the bearings install ? Are they in a machined block that the end of the shaft with a bearing slips into a machined hole ? Wondering if there were some alignment shims under one of these bearing blocks that got misplaced ? Do both bearings make noise or one side only ?

[Alex Zeller]

I would pull one of the rubber seals off of the old bearings (if you still have them) and see how much grease is inside it. It's possible that the factory didn't apply enough grease for the bearing and Byrd just sent you two more from the bad batch they have.

[Charles Coolidge]

Sounds like the bearings are in a bind, agree with Mike look for shims. Also did you accurately measure the OD of the old and new bearings, if the new bearings are larger they could be in a pinch. Something is out of kilter.

[Dennis Peacock]

I do have another set of bearings to put in it. I also still have the old cutterhead. Maybe I can measure where the old bearings sat on the original cutterhead and then measure the distance between the bearings on the new cutterhead and see if I have them slightly out of tolerance. I did notice that when I pulled the bearings off the new cutterhead when the 1st set went bad, that there was a bit of "side to side" play in the bearings upon removal that wasn't there when I installed the cutterhead/bearings. I don't get to choose where the bearing cups sit as they are threaded on the bottom side with a bolt hole to hold them in place on the jointer. So I'm wondering if the bearing spacing on the new cutterhead was a tad off when it arrived from Byrd and when I replaced the "bad" bearings, I simply installed the replacements in the exact same spacing because I didn't know any better and assumed that Byrd placed them where they needed to be as per factory spec. ??
Just trying to figure all this out because breaking down my jointer every couple of months is getting really old and expensive.

Powermatic says that this is the size bearing that goes on the jointer - 6204-2NSE and says that the part number is: BB-6204VV and that's what I last installed on the machine. I can order new bearings if I need to.

[Charles Coolidge]

I looked at the schematic in the manual. Are those outer blocks the bearing sits in a press on fit? It has to be a snug fit. One would press on the outer bearing race to install in the bearing block and the inner bearing race to press on the cutter head shaft so as not to damage the bearing. So to me the bearing would first be pressed into the bearing block pressing on the outer race, then assuming the bearing block now supports the inner race press the bearing block/bearing assembly onto the cutter head shaft.

I know the interwebs talk about beating these on with a hammer but a hydraulic press is really the way to go.

The last think I can see is to be careful with installing not to over tighten the long bolt that secures it to the jointer casting.

462540

[Dennis Peacock]

Charles,
The bearing blocks are a "press fit". They are snug and getting the olds ones out of the blocks when removing the original cutterhead was a chore. I did put on the new bearings on the new cutterhead with a buddies help who has a hydraulic press. And thinking back, getting those bolts loose on the original head was straining. Those were seriously tight and when I put it all back together with the new head and bearings, I was sure to "not" put it back that tight again. :)