View Full Version : bench grinder safty

05-12-2003, 04:44 PM
Gentlmen, Once a month we have a safty meeting on varied subjects at work. My name was picked to deal with the subject of "bench grinders" next week. We have 18 employees at this time, most of which are carpenters.They use the grinders the most for their planes and chisels. Any input about the safty/proper use of these tools would be appreciated. All of the grinders in our shops are 1 hp or less, from Craftsman on up. I have a pretty good understanding of safty but tips and proper use are needed. Thanks, Dave

05-12-2003, 04:52 PM
careful of "loading" the wheel, by using soft materials like aluminum on wheels. causes the wheel to crack.

05-12-2003, 05:06 PM
It can take minutes for the grinders to spin down and an unuspecting user might step upto one and not realize that it's still spinning.

Keep the covers on all the time.

This may be obvious but if the wheel has been dropped on the floor, then take it straight to the garbage. We all make mistakes and drop things, but no sense in causing another accident.

Full face protection, or at the very least eye protection.

I always use welding mask when I'm grinding, especially when I don't know the composition of the metal.


05-12-2003, 05:26 PM
Make sure the work support in front of the wheel is close enough to it so that the work can't be pulled into the gap.

Support the work on the work support, adjusting it if required. If you hold the work by hand, (as most all of us have, right?) it can be caught and thrown downwards. Sharp objects traveling out and down in the direction of feet (and especially other relevant body parts) are a bad idea.

05-12-2003, 07:05 PM
Grinder safety is very important.

When mounting wheels always use blotters on both sides of the wheel. These are the paper circles that go between the wheel and the steel flange. Remember one side is left hand thread. Don't overtighten the nuts.

Truing a grinding wheel is making it round and helps to eliminate vibration.

Dressing a grinding wheel opens up the grinding surface and exposes new cutting edges on the wheel surface.

The work rest must be within 1/8" of the wheel. This was mention earlier but without a dimension. The tongue guard, the one at the top of the wheel should be adjusted to 1/8" also.

Ringing a grinding wheel will let you know if it is cracked. Tap the grinding wheel very lightly with small hammer on the side of the wheel. It will ring if it is good. I will have a dull sound if it is cracked.

There are grinding wheel made for aluminum and should only be used for aluminum. Grinding aluminum on a regular wheel will cause it to load and the aluminum will melt and go into the pores of the wheel. When grinding on steel after the wheel is loaded the aluminum will expand and can cause the wheel to crack and explode. This was covered before but it is so important it needed to be repeated.

Sounds stupid, but I have been asked several times what the little tray on the front of the grinder is for. It is used for water that is used to cool off the part being ground.

Never grind on the side of the wheel. If it is grooved the wheel is ruined and could fail.

I will look for some of the books I got when I attended a grinding school at Norton. If I can find them and find some additional information I will post again.

You might want to look at the Norton or other manufacturers web site. They may have a lot of information you cna use for the safety meeting. I have not looked at them.

Good luck with the safety meeting. I think it is great to get the workers involved with the safety meeting. We did the same thing where I worked.

Hope this helps,


T Wise
05-12-2003, 07:49 PM
That 1/8" dimension is important, also important to note that it is every operators responsibility to make sure that the guards are set properly. I mention this because I had a new journeyman in the shop the gap was around half an inch, he proceded to question people as to who was responsible for maintenance on the grinders, I told him it was his responsibility if he was using it. I got a blank stare and he went about his grinding (not bothering to set it up) I believe it's in the act regarding operator responsibility but I can't quote where. That was pointed out to me after a co-worker got his finger pulled into the gap a few years back.

05-12-2003, 10:05 PM
To quote "alfred E neuman" What me worry? usually the attitude of all uninitated workers till the trip to the hospital. What I hate is them almost sending me through thier actions or inactions.

I got all my fingers, but do have a few scars.

Grinder stress, is a action of harmonics, pressure applied and rpm, I have seen hundreds of grinding rocks run at the wrong speed. When a hand grinder rock comes apart, one of the bad times the guys intestines fell out on the floor. My older brother a PE, built a box and a air motor to overspeed a like grinding rock to prove to the court it had been misused. The poor guy who was out of work got less money, but a real hard education. (he still got a lot) When you think of it, he is lucky

05-12-2003, 11:21 PM
All good points. Every grinder in my shop came with a manual. In those manuals there's a pretty lengthy check list of safety precautions and operating instructions. Has anyone ever read them?
You should be having your employees "sign-off" on instructional training. That's my tip.

05-12-2003, 11:53 PM
Check out the following web sites for more information.

http://www.ccmsi.com/losscontrol/Other/An%20Abrasive%20Subject%20The%20Grinding%20Wheel%2 04201.pdf

Can't get to my books.

Correction to my last post should have said hammer handle and not hammer for the ring test.


L Webb
05-13-2003, 12:05 AM
All good advice so far.
The ring test is absolutely required for any wheel before mounting.
One thing I haven't seen addressed is wheel shelf life. Manufacturers put a date on the wheel. It is good for about two years, depending on how they've been stored. You can send the wheel back to the manufacturer for re-testing for a price.
Check out Norton's site:
Plenty of good info there on all abrasives.

05-13-2003, 12:18 AM
If a wire wheel is mounted keep long hair tucked in your shirt,otherwise you could get a closeup view of the guard,and a new bald spot.

05-13-2003, 12:36 AM
All that being said... There are lots of places to get grinders. HF sells them - they don't look bad. I see them on ebay, for not much more - but the advice to me was don't buy a used one... They need to meet OSHA rules because it is your eyes those rules are out to protect - and old rotary grinders may not meet standards.... It's why they might be on Ebay.


05-13-2003, 01:39 AM
Grinders are one of the most necessary and useful tools to have handy. All the advise I've read here is sound and proper, but I think that you should present your safety information in a way that helps your audience apreciate the risk, and develope good habits and practice and yet does not intimidate them or raise their consern too far above what their experience is. If you can get a person who has used grinding wheels for years carelessly to use safety glasses that is a great accomplishment. If you can get all users to use a full face shield that is a great thing. A good practice is to have the full face shield hanger in the way of the power switch. The face shield has to be removed before the switch can be accessed. Another tip is to hold all small bits in vise grips when grinding.
That's all I have to add.

05-13-2003, 04:16 AM

All good points. I do take issue with dipping tools into water to cool them, however. It is best to never let the cutting tool get hotter than you can hold with your bare hands. When it does, it is best to let it cool naturally - placing it on a granite plate will cool them quickly.

Dunking in water can affect hardness and temper. Dunking can impose significant thermal shock to the material and micro fractures occur at the thinnest section - the cutting edge. Carbide is more sensitive to this than HSS - dry machining with modern carbides is recommended because of this.

[This message has been edited by Thrud (edited 05-13-2003).]

05-13-2003, 09:41 AM

I agree the water is not for dipping over heated tool steel. You are correct about micro cracks and temper. I don't use it for cooling tools. I do use the water for cooling steel so that it never gets so hot that you can't hold it. If you keep the temperature down by frequent dipping it will never get too hot.


05-13-2003, 04:50 PM
Gentlemen, Again, it staggers me as to the depth of readily available good knowledge at this site. With what I already knew and the info I just got from all of you, half of which I didn't know, I feel I can give a very good class to my workers. This is a subject I didn't want to skimp on. Again, thanks. Dave

05-13-2003, 05:02 PM
My shop safety rules for using the bench and pedestal grinders:

Pedestal and Belt Grinders
All general safety guidelines will apply to the pedestal and belt grinders, and will be a part of the safety test. The listed guidelines are specific rules regarding the operation of these machines.

1. Always wear safety glasses when grinding on any pedestal or belt grinder. The shields on the machine are not a replacement for safety glasses.

2. Avoid grinding on the side of the wheel.

3. Keep the tool rest adjusted to within 1/16" from the face of the wheel. Adjustments must be made when the tool rest gap approaches 1/8".

4. Hold the workpiece securely when grinding. Small parts being ground will be held with lever locking pliers (vise grips), and not pliers.

5. Move the part being ground across the face of the wheel, not allowing the piece to "dwell" in one place.

6. Be sure that the grinding wheel is not operated at speeds in excess of the RPM marked on the grinding wheel label. Check machine ratings and wheel ratings prior to mounting.

7. Use a ring test to be sure grinding wheels are not cracked before mounting the wheels on the grinder.

8. When mounting the wheel, the round paper labels (blotters) must be on the wheel, and the wheel is then mounted using the large steel washers on the machine.

9. Avoid personal contact with the wheel.

10. Stand out of line with a grinding wheel when starting it up, and allow it to run for one minute prior to
using if it has not been recently run.

11. Gloves will NOT be worn when grinding. Loose clothing will also be secured.

12. Proper ventilation will be used when grinding to prevent grinding dust in the air.

13. All guards, tool rests, spark deflectors, and safety shields must be in place before grinding.

14. Be certain the belt on the belt grinder is centered before starting to grind.

15. Check the belt for tears prior to starting the machine. Do not use a belt with tears in it.

16. Hold pieces to the bottom "quarter" of the buffing or wire wheels. This prevents parts from injuring you should you let them go while buffing.

Caleb Ramsby
05-13-2003, 05:09 PM

I have been blacksmithing for about two years now and have experienced hot steel trying to jump out of the forge at me, hot scale(instant rust formed on the steel) flying onto my arms and legs, sparks from the fire burning me and so many other hazards it isn't funny, well. . . OK it is a little funny. However I believe the grinding wheel to be the most dangerous tool that I use, period. Whenever I can I file a piece instead of grinding it, although this is not always possible, I do.

Please go to:


Scroll down to demo's 66 and 69. PRINT them out, SHOW them to your temperary pupils and then PUT them up on the wall.

From what you say, it sounds like you work in a safty aware enviroment, be thankfull and proud, because you are in the minority.

Caleb Ramsby

Caleb Ramsby
05-13-2003, 05:14 PM
Hum, after re-reading all of the post's I noticed that no one says anything about hearing protection. One should always wear hearing protection when grinding. Just thought I would mention that.

Caleb Ramsby

05-14-2003, 02:48 AM
One thing my high school shop teacher told us about eye protection and grinders has stuck with me for 25 years:

You get that wheel grit stuck in your eye, it is very small and hard to see, and non-magnetic. The eye doctor is going to have a tough time finding it to get it out. (bout the only thing worse is clear glass shards!)

Think of all the difficult jobs people bring to you - some born out of stupidity / ignorance - and you're going to make it hard on a eye surgon -- to fix YOUR eyes.

Much better to aviod the situation - use the facesheild.

Just something I never forgot

05-14-2003, 05:31 PM
Gazooks man, you ae lucky! Of course I agree with all aspects of proper safety gear and safe use of equipment. I never stated that, but around here the key words are "Safety First!"

Peace & Grace brother

Caleb Ramsby
05-15-2003, 12:59 AM

Actually the guy with the mangled nogen is Jim "Paw Paw" Wilson. He is a VERY experienced blacksmith and a war veteran, so when he says that something is dangerous and caution should be taken, then I listen. Those pictures say more than any words can, just 1/4 of an inch more and he would have been blind in one eye. . . or both.

Peace and Grace indead!

Caleb Ramsby

05-15-2003, 01:38 AM
Are you writing a rule list that will become company policy, or presenting a safety presentation. There are subtle differences in the approach and what it means to the worker. There are good practices, proscribed practices, routines and good routines. There is also a level beyond all of these that is developed by people who have never done any work around machines and who are terrified by all the the processes that we use (can you say "HR"?) Anything loud, or big or hot or whatever they can't handle it, so they adopt a "super parent" mode and they have to write rules to protect everyone from everything. In truth they are just creating lists of reasons for the insurance companies to deny a claim. I never want to work for a shop that is so big that the insurance policy runs the policy of the company. I like safety and it is very important. But I don't like shops that fein a safety policy on the written company policy while pressuring the employees to violate that same policy. And in the case of an injury, leave them out in the cold.

[This message has been edited by SJorgensen (edited 05-15-2003).]

05-15-2003, 09:33 AM
Every one should read Spencer's latest post (above). It describes very well our present relationship to government and OSHA and the green types. Just read it with govert programs in mind.

In my opinion, a bench grinder is probaly the MOST dangerous machine in most shops, but I gets little attention because it is quiet, looks as though any one could run it and how could that smooth wheel really hurt any one? Damn things are dangerous from time you unpack the stone (ring test) until long after the power is removed (wheel still spinning). Never know if the wheel is cracked by the last user untill it sprays rocks. Buffing wheel are just as bad.

Maybe we need to go back to knowingly taking chances, and personally avoiding injury, rather than thinking some else has made it safe, and if its not safe I have safety gear to protect me, and if that gear don't work then i have insurace and a lawsuit, and all else failing- I can go on workers comp or SSI and not have to work.

That last option (comp/ SSI) is harder to keep in effect than going to work is.

05-15-2003, 10:01 AM

Thanks for the link and the great pictures! I'll use these in my classes when we cover grinders. Your efforts may well save some teeth, eyes and faces!!

05-15-2003, 10:02 AM

Thanks for the link and the great pictures! I'll use these in my classes when we cover grinders. Your efforts may well save some teeth, eyes and faces!!

Caleb Ramsby
05-16-2003, 01:57 PM

I apreciate the thanks, however I don't deserve much credit.

Jock Dempsey is known as the Guru at Anvilfire he spends easily 10 hours a day working on keeping the site going and answering question at the "Guru's Den". Jim "Paw Paw" Wilson is another staple to the site and although a full time blacksmith he also spends much time answering questions on the site.



The former is the "Guru's Den", a forum for all things metal, the latter is know as "Paw Paw's corner" or "The Virtual Hammerin" and is an informal meeting place of the minds.

They would GREATLY appreciate it if you would pop by either of the mentioned bulletins and post a quick thank you for the saftey demos. They don't make any monitary profit off of their work on the site and are doing it just to help people.

Caleb Ramsby

05-17-2003, 06:13 AM
Gents, Again thanks for all your input.Always good to hear other sides. Seems we get to lax sometimes and thats when it happens. Seeing Paw-Paw really brings home the need for a safty meeting on bench grinders! I feel that no one at my work has any idea of the potental hazard that could result from improper use that I see most every day. I never understood the severity of it all. To answer you directly Spence,The safty meetings are thought up by us to be used by us and to also maintain a good repore with the local OSHA that has come around often. Last year we were inspected by them and got a 750$ fine which when we arbitrated, even that was wiped out. We were all very proud about the final report. EVERY person at work is self motivated about safty and we have an open policy about it but no one feels its to anal. I think our system is working, we just need to keep at it. This safty meeting next Monday will really open their eyes. Thanks all, Dave

Alistair Hosie
05-17-2003, 04:29 PM
I just had to add one thing that I don't see mentioned ,I witnessed a very serious accident many years ago when my bosses wife got her long hair caught in a polishing lathe. There was blood and tears, no'one really thinks enough about long hair and a turning machine be warned this is very serious and take note of this to tell others regards and good luck Alistair

05-17-2003, 04:48 PM
Alistair, A good captain friend of mine (female) went to check the drive train on a delivery, long hair caught in the shaft and ripped half her skalp off. Lucky they were close enough to the coast to be air lifted to a hospital. All is fine now. Long hair and machinery sucks. Dave

05-17-2003, 04:48 PM
Alistair, A good captain friend of mine (female) went to check the drive train on a delivery, long hair caught in the shaft and ripped half her skalp off. Lucky they were close enough to the coast to be air lifted to a hospital. All is fine now. Long hair and machinery sucks. Dave