Building Harold Hall's Simple Grinding Rest

[Technical Ted]

What wheel, brand/size/style/number are you using? If you spin the wheel mounted on the grinder by hand does it look like it's running out?

You said that the adapter you made fits both the grinder's arbor and the wheel without play so that sounds OK. Some people balance their grinding wheels so that is a possible option. If it were me, I would dress the wheel with a diamond dresser using one of your holders on the grinding fixture you made so it is nice and true and see what that does.

Ted

 

[stioc]

It's a Norton 38A Type 6 Straight Cup wheel. I put the old wheel back on (which doesn't pass the 'ring test' btw) and it's way better. So there's definitely something going on with the adapter or the wheel.

 

[pontiac428]

Dressing the wheel will bring it into balance. If that doesn't work, you can balance the wheel on a static point and remove a little bit of material to adjust as if static balancing a tire. I've never done that, just read a writeup on how it's done. Usually wheels balance out with dressing.

 

[stioc]

Dressing the wheel will bring it into balance. If that doesn't work, you can balance the wheel on a static point and remove a little bit of material to adjust as if static balancing a tire. I've never done that, just read a writeup on how it's done. Usually wheels balance out with dressing.

Even a quality wheel like the Norton will require dressing out of the box? I ask because I've never replaced a grinding wheel before.

I hope you guys are right though because I keep thinking I failed at making the adapter somewhere but can't see where. The two surfaces the wheel registers on check out as well as the fit on the arbor.

 

[HBilly1022]

I had similar issues with my grinder. At first I thought it was the cheapo grinder but after checking it over and running it without the wheel I determined it was not the grinder. Then I dressed the wheel using the HH rest and a diamond point dresser. No change. I ended up making something like Johnny C did in this thread https://www.hobby-machinist.com/threads/do-they-make-bench-grinders-that-dont-vibrate-so-much.67471/#post-564126 and the difference was astounding. Ended up with a very smooth running grinder that amazes me every time I turn it on. You will also see there is a OneWay balancing system that does the same thing but may not be applicable given the wheel and adapter you made.

 

[pontiac428]

Everything needs to be dressed true when new. The arbor and your spindle are part of that equation, and dressing levels the differences. It's not common, but I've had a wheel or two new wheels (one 6" bench grinder wheel in particular currently on my pedestal grinder comes to mind) that needed 1/8" of dressing before smoothing out.

 

[Technical Ted]

The two surfaces the wheel registers on check out as well as the fit on the arbor.

How does the arbor fit the wheel? Even if you made it right on 1.250" the wheel might fit sloppy and maybe you can wrap a shim around the arbor to help align the wheel. But, you should still dress it with a diamond.

Also, another thing to put on your to do list... you'll want to extend the wheel guard so you are protected in case the wheel explodes. Safety first!

Ted

 

[stioc]

Will do more checking and testing tonight.

The thread that HBilly linked to, I found @MikeWi post #20 similar to my situation, looks like the solution was to dress the wheel!

@Ted, I was looking at the wheel guard but I haven't yet figured out how to extend it but I will (that was going to be my next project on this after mounting the new wheel.

 

[ericc]

All this hassle with the balance has made me want to go with a slow speed grinder. I just saw my friend's this weekend, and it is great. That will be my next one.

 

[stioc]

Haha, or just buy the real tool...but where's the fun in that if you're a glutton for punishment like I am lol

Well, things are much better now after dressing the wheel. There were a few high spots. When it's running at full speed it's about the same as it was with the original wheel, in fact, it sounds/feels smoother. However, at spin down, may be around 1500-2000 rpm there's some wobble/shake but not terrible. My grinder isn't bolted down and it doesn't walk around on the MDF board it's sitting on so I think it'll do.



As for the guard, my original one covers 1" of the 1.5" already... I can't cover the sides on this one either since this is a cup wheel and I'll be grinding on the side so I'm thinking of leaving it as is or may be fab some sort of a half guard?