My little 5” Black and Decker No. 7900 bench grinder crapped out

[JDHasty]

I bought it new about forty years ago and it’s never was a quality tool. That being said, it lived under my bench mounted to a wood base. I could pull it out and clamp it in my woodworkers vise in a minute or so, and used it all the time. It usually had a fine stone on one side and a cotton wheel on the other and more than a little pressure would stop it.

In all honesty, having it bog down under any but a light touch was a feature I appreciated, not something I considered a defect.

Is there something comparable out there?

I have a heavy duty grinder that is permanently mounted to a steel table in the garage that gets a lot of use, but I really want another little light duty bench grinder.

[M-Tecs]

Take your pick.

https://www.amazon.com/s?k=bench+gri...l_7zul2axelq_p

https://www.bing.com/search?q=little...ANCMS9&PC=W000

[DukeSoprano]

https://www.harborfreight.com/power-...aft-58967.html

I bought this a few months ago, it has adjustable speed and it does bog down.

[JDHasty]

I saw that, it would work well for sharpening card scrapers and fisher scrapers. Any small bench grinder would work for touching up the end of pins and such, but not so well for polishing. The wheel just wouldn’t get into confined spaces. One thing I liked about the one that quit is that it didn’t have enough torque to yank what I’m working on out of my soft jaw pliers and throw it across the room.

[fg-machine]

I guess everyone looks at things in a different way , I've always viewed under powered grinders much the same as a dull knife , more apt to cause Injury then a sharp one .

That wheel slowing down and not maintaining surface speed is what causes things to get thrown , couple that with poorly maintained wheels and that's how injuries happen .

I used a 10 hp duel spindle grinder for 30 years for everything big to small and can't say I ever had an issue with it grabbing parts .
Because I kept the wheels dressed .

[country gent]

I have a little Harbor Freight 5" or 6" i bought and converted to use to sharpen tig electrodes with. I think its a 1/2 arbor. does good but dosnt get used a lot. for a small grinder polisher you might look into a variable speed model sometimes slower buffing is better.

[405grain]

My 6" pedestal grinder went Pop and gave up the magic smoke last year. The capacitor blew out, and because it was an internal capacitor on a Chinese made motor I decided that it wasn't worth rebuilding. I had become dissatisfied with the 6" grinder's lack of power and low precision; It was time for an upgrade. I got a Metabo DS 200 grinder with 8" wheels. It was like going from a wheelbarrow to a Ferrari. It's quieter, vibrates a lot less, cuts much smoother, has more robust parts, and is easier to use than smaller grinders. Lathe cutting tools that I sharpen with it leave a much smoother surface on parts than the ones that I used the old grinder to sharpen. If you can swing it, instead of replacing a small grinder with one the same size, see if you can upgrade to a better grinder. Everything that you make with it will thank you.

[country gent]

I have a jet 8" grinder 3/4 hp that I use to sharpen drills and lathe bits. Its a great tool runs smooth with no vibrations ( you might have to do a little tuning on the washers or wheel balance with even top name grinders). the bigger wider wheels make grinding easier. I would like a little bigger rest on most grinders.
several things to make sure with grinders.

1) keep the rest properly set parallel to wheel and 1/16 away but not touching. This keeps parts from grabbing and pinching
2) keep the wheel dressed and running true.keep the face with radius on it. this improves cutting and slows burning of parts. It also makes getting a true single grind pattern
easier.
3) keep the spark arresters properly set. This keeps sparks out of your face and eyes and if a part does grab it cant come around and hit you.
4) keep the eye shields in place and set
5) balanced wheels run truer and dont vibrate making the grinder walk. They also increase the bearings life.
6) when mounting a wheel ring test it. hang it on a screw driver and LIGHTLY tap it with another, it should ring not thud a thud means there is a crack in it and its compromised.
If new return it if used break it apart so it cant be used.
7) when starting a grinder stand to the side start it and let come up to speed then let it run for a minute.

[StrawHat]

I use a slow speed grinder (1700 rpm) in my business. It does not bog down unless I am being foolish. But it works better than the normal speeds, 3500 rpm.

Kevin

[JDHasty]

Thanks everyone for the suggestions. I have a nice heavy duty grinder, I keep the wheels dressed and have a dozen, plus wire wheels for it. This little guy has been so convenient over the years. If I have some little job to do I can pull it out and if necessary change out the grinding wheel to a wire wheel or to a coarser or finer grit or buffing wheel in a minute and it’s right in front of me.

It probably does seem odd that I use it, but it’s been just what I’ve needed. I talked to a guy at the saw shop who told me the five inch wheels are not that available any longer. They still make them for scissor sharpening machines, but that is the only application they get any call for them for.

[Bazoo]

I have a jet 8" grinder 3/4 hp that I use to sharpen drills and lathe bits. Its a great tool runs smooth with no vibrations ( you might have to do a little tuning on the washers or wheel balance with even top name grinders). the bigger wider wheels make grinding easier. I would like a little bigger rest on most grinders.
several things to make sure with grinders.

1) keep the rest properly set parallel to wheel and 1/16 away but not touching. This keeps parts from grabbing and pinching
2) keep the wheel dressed and running true.keep the face with radius on it. this improves cutting and slows burning of parts. It also makes getting a true single grind pattern
easier.
3) keep the spark arresters properly set. This keeps sparks out of your face and eyes and if a part does grab it cant come around and hit you.
4) keep the eye shields in place and set
5) balanced wheels run truer and dont vibrate making the grinder walk. They also increase the bearings life.
6) when mounting a wheel ring test it. hang it on a screw driver and LIGHTLY tap it with another, it should ring not thud a thud means there is a crack in it and its compromised.
If new return it if used break it apart so it cant be used.
7) when starting a grinder stand to the side start it and let come up to speed then let it run for a minute.

Thanks.