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The use of Blotters for grinding wheels is required in USA and Canada

michiganbuck

Diamond
Joined
Jun 28, 2012
Location
Mt Clemens, Michigan 48035
Recent web browsing cold saw sharpening machines I saw quite a number of such machines being used with not using a blotter with a vitrified wheel. Vitrified wheels are abrasive grits welded together with melted glass or clay…Abrasive grits are irregular shaped and wheel sides are never exactly flat. The blotter allows tightening a wheel with little chance of a grit edge cracking the wheel. Such a cracked wheel is likely to Blow Up at high RPM. With these machines one may have one's face right in line with the blow-up wheel.
That a wheel might come new with no blotter, or if a manufacturer does not state to use a blotter is no excuse not to use one. Their use is the law in the USA and Canada. "I didn't know" is not a valid excuse for an employer ..it is your responsibility to know. Yes if you can't find the one you need, one can make them with heavy card paper like of a cereal box.
USA
(6) Blotters.
(i) Blotters (compressible washers) shall always be used between flanges and abrasive wheel surfaces to insure uniform distribution of flange pressure. (See paragraph (d)(5) of this section.)

Canada OSHA
Wheel Mounting on Portable Grinders : OSH Answers
 
You are talking about the paper on the sides of wheels?
I don't think that I've ever seen a wheel w/o one - unless it fell off in storage or sumpthing, but ...
Yeah, I wouldn't want to run one w/o a paper.


As for the law:
I'm Shirley not going to fret over not knowing what I don't know.
If I learned sumpthing new, I'm sure that I would be forgetting sumpthing else, so what's the point?


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Think Snow Eh!
Ox
 
You are talking about the paper on the sides of wheels?
I don't think that I've ever seen a wheel w/o one - unless it fell off in storage or sumpthing, but ...
Yeah, I wouldn't want to run one w/o a paper.

Many of the larger wheels have loose paper rings that you need to install on both sides of the wheel during replacements. Think cylindrical and centerless grinders where wheel bores can be over 12".

Usually the wheel vendor will provide plenty when you buy a single or multiple wheels, but if they get lost during storage they should be repurchased, or (if you're in a rush) made from larger card stock.
 
Only time I've ever seen wheels used without blotters was when they've been deliberately removed to allow epoxy bonding to a metal backing plate. Many years ago there was an article in Popular Mechanics about doing that so the sides of a wheel could be safely used for tool grinding. That was back in the days when PM was a real DIY magazine rather than a collection of fluff pieces interspersed between the ads.
 
In wet grinder applications I have found that composition gasket material works well. It interfaces with the wheel like card stock but won't come apart when wet.

Tom
 
Timely post. I just resurrected a 1HP Jet grinder that had been disassembled for awhile. Don't recall noticing the blotters/washers when mounting wheel. I'll check.

But it's nice to have a grinder that doesn't get bogged down very much.
 
Wrote that after seeing grinders on YouTube with wheels being mounted with no blotter. The machine likely from China and who knows about the wheel. That is a No No and perhaps the China company does not know that. Or the OP on the YouTube doesn’t know.
Still us old timers should try to keep the ununs and newbees safe…Or the Grubberement might take away our machines.

Yes, I looked for a machine manual buyt no free ones there.
 
Gardei is a source of blotters
They may seem expensive but being reusable is a plus. Wheel vendors will supply them for free with wheels. surface grinder and bench wheels most often come with them already attached.
They are attached with a simple water-soluble glue and so can often be soaked lose form a wheel being discarded. Getting wet does not ham then. To attach Elmer’s glue or a simple glue is used with only putting a few spots of glue, just enough to lightly hold them on.
Coolant does not harm them because of the material they are made of, and because the holding flange and wheel mount face is tight and keeps coolant out. Even soaking a wheel to remove the old blotter for re-use does not hatm them. I estimate 1:20 wheels will blow up with not having a blotter in place..so thet could be the very first..
The ring test assures the wheel is good..and then the use of the blotter keeps it that way.
An abrasive grain edge, facet. or corner pushes againest the glass holding the wheel together and cracks the whweel. The operator does not even know it is cracked. then with running the wheel blows up.

Grinding Wheel Blotters | Tonawanda & Amherst, NY | Pioneer Printers
 
Here is a note from Norton wheel company

“A question was asked, “What diameter blotter must I use when mounting a grinding wheel?” The answer is simple. The blotter must be equal to or greater than the machine’s mounting flanges.”

I think the blotter should be large enough that the operator can see it sticking out 1/8 inch or so in order that the next person to use that machine can see that it is in place. I have used wheels from 1/4" ID wheels to 72"OD wheels and they all have had a blotter that you could see when the wheel is mounted. Yes, the large wheels have the blotters separate/lose and one attaches them with a few spots of grease.

The grinder that I started this thread about has no blotter edge showing even on the manufacturers site. I will call them today and ask about blotters.

Oh I should also mention that the "mount up" is a gravity thing because a big wheel has a hole larger than a close fit and the mount up makes them run true with the "mount up" pointing up. I entered one shop where they staggered the mount up in a gang set, they wondered why they ran crazy bad at the start. After I explained and set up a wheel set correctly, they saw a great difference at running and at the first wheel dressing.
 
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Here is a note from Norton wheel company

“A question was asked, “What diameter blotter must I use when mounting a grinding wheel?” The answer is simple. The blotter must be equal to or greater than the machine’s mounting flanges.”

I think the blotter should be large enough that the operator can see it sticking out 1/8 inch or so in order that the next person to use that machine can see that it is in place. I have used wheels from 1/4" ID wheels to 72"OD wheels and they all have had a blotter that you could see when the wheel is mounted. Yes, the large wheels have the blotters separate/lose and one attaches them with a few spots of grease.

The grinder that I started this thread about has no blotter edge showing even on the manufacturers site. I will call them today and ask about blotters.

Oh I should also mention that the "mount up" is a gravity thing because a big wheel has a hole larger than a close fit and the mount up makes them run true with the "mount up" pointing up. I entered one shop where the staggered the mount up and they wondered why the ran crazy bad at the start. After I explained and set up a wheel set correctly, they saw a great difference it the first wheel dressing.

Hi matey. One place I worked at did a lot of side grinding on a big cylindrical grinding machine as well as OD grinding . They used roughly 30" dia by 3" thick wheels. Health and safety got a bit nervous about the side loading as the wheel got thinner with wear and dressing etc so we got the makers representative in. He came up with a wheel that was like a 30" dia ring 3" thick but with about a 24" bore. It had threaded brass inserts glued into one side the ring. The idea was you bolted the ring to a steel backing arbour that mounted on the Machine just like a normal wheel.

It worked OK but the operators couldn't be bothered changing the wheel every time they had some side grinding to do so after a short while the wheel just got left on the rack. H&S had ticked the box by providing the wheel, so they were happy.

Have you ever come across a similar wheel ?

Regards Tyrone.
 
Don’t know exactly what you are describing. One odd wheel builds up was Blanchard type wheel, likely it was for a Blanchard . We would set the segments in a pocket/bucket wheel mount and then melt sulfur to pour in and so make the assembly a home-made wheel. Sulfer turn like a glass hard glue to hold it all togethrt.
 
Talking about wheel safety we should teach an apprentice to Never walk away from afersh monted wheel with not dressing it. The next guy to run thr machine should not have a dangerios surprize.
 
RE: wow I really messed up the spelling on post 13...sorry my bad.

Talking about wheel safety we should teach an apprentice to Never walk away from a fresh mounted wheel with not dressing it. The next guy to run the machine should not have a dangerous surprise.

No I was not drinking ..just not paying attention I guess
 








 
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