Gallery, Projects and General > Project Logs
Spindle problem with cincinnati tool and cutter grinder 2 spindle
PekkaNF:
This "normal" SKF 2305 was the one first giving the grief, but the other (pair) has detectable noise too.
This 2305 is easy to find pretty much exact replacement, but the paired ball bearing 6305 arrangement is harder to find. Size is common, but the clearance and accuracy needs to be sorted out
Pekka
PekkaNF:
Now this got interesting: Started whing on coffee about my grinding machine spindle bearings and consensus was that new brand name SKF/FAG deep grove ball bearings standard accuracy class tends to be P5 or close and I might be better off choosing C3 clearance and match/fit bearings myself that trying to find matched pair. Easier option would be to buy pair of universal angular contact bearings, they should fit straight out of package, no fitting&faffing...only to check that critical loads do not exceed demand....deep groove ball bearings and angular contact ball bearings are rather different.
The story (they say) about C3 P5 is that larger than normal clearance (C3) might be actually better if I plan to shim (or preload) the clearance out...those bearings do not cost arm and leg, might buy two just to check if they can be measured and tried out.
Choices.....
Pekka
*Forgot C3*
gerritv:
Sounds like all round good news.
And perhaps hope for when I decide mine are too noisy to live with. I think I have a matched pair of 205W's at each end, can't tell until I take it completely apart. And that means replacing the bearings anyway :-(
PekkaNF:
Very often bearings are hard to remove without putting pressure on correct bearing ring, thus brinneling the bearings. Therefore I used no hammering and minimum amount of pressure. I want to measure/check the bearings.
I am not mechanical engineer, but there are quote a few I can talk to and one in particular has been designing and making big industrial gear boxes and developing methods to produce parts of them. Like to talk to him, because he is very hands on person, although got later in life doctorate degree, cut's fast trough bullshit and tells me often that I have been reading too much and spent too little time looking bearing tables and intimately understand what they actually mean in practice.
I rinsed the bearings yesterday with grease remover, dunk them on ultrasonic cleaner, dunk them on IPA (to remove water) and gave a drop of oil to be able to check them.
Then a friend came to check them. He said that the bearing surfaces looks pretty much good enough and I could clean then further (looks like grease interacted with cage and "plated" it) and reuse them. Totally unexpected. He explained that the noise I heard most likely came from gunked grease and released "plating" from the cage.
2305 bearings have certain amount of play, C3 internal clearance seem to be standard, threfore the play I measured from floating end is not alarming for this bearing type.
http://www.skf.com/pk/products/bearings-units-housings/ball-bearings/self-aligning-ball-bearings/self-aligning-ball-bearings/index.html?designation=2305%20E-2RS1TN9
Values: ISO 5753-1. Values are valid for unmounted bearings under zero measuring load.
http://www.skf.com/pages/jsp/catalogue-table.jsp?id=tcm:143-138591
That means effectively that I should mount the wheel on the other end I had it.....no problem. I need to buy the belt anyways, might use 30€ for new bearing and dab it with good grease.
Other end (2*6305 deep groove ball bearings) is still under consideration, exact replacements are hard to get, original ones are shedding debris from ball cage and they are not measured yet. I may need to buy pretty good ball bearings, measure axial deflection under preload and stack them with shims between inner and outer races...never done it on this accuracy, would be new and firs one for me.
I need to buy belt anyway, I'll give me few days to think this over and maybe I can devise ways to measure old and new bearings?
Pekka
Andrew Wildman:
Sounds like fun and games. I hate fitting bearings. Always seems that even with the correct procedure results are variable
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version