Kidbee 21st March 2012, 08:28 PM The bench grinder at work started to seriously vibrate a few months ago. The grinding wheel had been replaced with a better quality one. It went okay for a while and then the vibrations started. I Googled forums and did everything to correct the problem with no result.
Thought I would replace the wheel for another and the problem stopped for awhile and then started again as the grinding wheel speed increased.
I had another old Skil wheel in which the diameter of the hole in the wheel matched that of the axle it fitted on to. The grinder stopped its vibration with this wheel.
Both the other wheels had had nylon bushes and that appears to have caused the vibration.
Think I will buy a nylon rod and make my own or turn up some hardwood ones.
Gary
Tools4Me 21st March 2012, 11:53 PM The bench grinder at work started to seriously vibrate a few months ago. The grinding wheel had been replaced with a better quality one. It went okay for a while and then the vibrations started. I Googled forums and did everything to correct the problem with no result.
Thought I would replace the wheel for another and the problem stopped for awhile and then started again as the grinding wheel speed increased.
I had another old Skil wheel in which the diameter of the hole in the wheel matched that of the axle it fitted on to. The grinder stopped its vibration with this wheel.
Both the other wheels had had nylon bushes and that appears to have caused the vibration.
Think I will buy a nylon rod and make my own or turn up some hardwood ones.
Gary
Gary, could it be that the nylon bush is loose on the shaft (or loose inside the stone)? Maybe after a little while running it gets off-centre and vibrates? Have you dressed them?
dr4g0nfly 22nd March 2012, 06:41 AM Mines done this a couple of times, maybe I'd better strip the wheels off and have a look-see myself.
Thanks for this post.
Lumber Bunker 27th March 2012, 12:18 AM Nylon bushes not fitting the shaft of the grinder is a problem. - get some that fit
new stone wearing unevenly is another - dress with dimond dressing tool. to remove "out of round"
incorrect installation of wheel - read the instructions
anything else?
Tighting the nut down and dress the wheel will fix the vibration. most times.
Kidbee 28th March 2012, 07:44 PM Both nylon bushes in question were made up of four different segments. I guess the reason for this was that inner individual segments could be removed to adapt to different sized spindles.
A colleague and myself both dressed the wheels with diamond dressers but in this case it did not stop the original vibration.
One of the stones was a good quality white Norton wheel and they had the segmented nylon bushes.
I now have some solid nylon rod to make the new ones. Thanks for your interest in this matter.
Gary
derekcohen 28th March 2012, 08:46 PM All grinders benefit from having their wheels balanced.
This means marking a line on a wheel, loosening and moving the wheel slightly, checking the vibration, loosening and moving it some more, etc ... until the vibration reduces to its limit.
Do this after truing the wheel.
Regards from Perth
Derek
Paulphot 30th March 2012, 01:45 PM I had this problem with a cheap brand grinder and my 6" Abbott and Ashby grinder. Fortunately for me I have a lathe so I turned up some bushes out of redgum and with a bit of strategic sanding, perfect fit and no more vibration.
vk4 31st March 2012, 08:22 AM YES unfortunately the bushes supplied by manufacturers these days are average to say the least, I worked in the industry for nearly 20 years.
A lot of the issues I saw , were caused by lock nuts not being tightened and the bushes coming out of the wheels (not sleeve bushes), I think that your solution for a solid bush will solve 99.9% of your problems.
With regard to NORTON products, (company now owned by St Gobain), they are a commercial product and designed for the general consumer, there are other brands for the industrial users.
soundman 1st April 2012, 02:54 PM The fit of the suppled bushes is a knwon and common issue, if you are at all fussy turning up a set that fit snug is the go.
This is particularly imporatant if you are using the wheel for sharpening
Forget the plastics, it is much easier to get a good fit out of some good dry hardwood.
Unless you are going to spend on exotic plasitc there are difficulties in getting a good accurate and temperature stable fit.
I did mine out of spotted gum, do not try to make the fit by measurement do the fit by trial and error starting with a fit that is too tight and scrape little by little till it is snug as.
Make sure the blank is good and dry......dry it in the microwave if you must.
if the bush goes in dry, you will have no issues with moisture changes.
The other thing you may have problems with is the flanges supplied with the grinder......they are very rarely flat and true, either you can bash and lap them flat on a belt snader or buy prelapped ones from a lapidary supplier.
once you have the wheel all running true, you can rotate each of the flanges and the wheel on the shaft to get the best balance possible...then dress the wheel.
All this fiddle is well worth the trouble to get a smooth running grinder..especially if you are doig sharpening or any other accurate work
cheers
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