surface grinding basics

You are hopefully familiar with how your machine is lubricated. Once the ways are well lubricated and moving very smoothly, then mount a tenths indicator up by the wheel and indicate just the face of the chuck itself. It should be a great deal flatter than .005"! If it is in fact out by .005" then you will have to grind in your chuck itself. Google on the term "grind in" and I think you'll get all you need.

Small grinders sometimes get much better finishes if you use a dressing stone to break the corners of the wheel.

Grant Erw> I recently purchased a new basic surface grinder similat the the basic

Are you using coolant?

One reason people like 3 ph motors is that they don't have the pulsations of a 1 ph motor. The latter can cause waves in your work. Also, an out of balance motor, out of balance wheel, bad wheel bearings, bad belt, can all cause similar (and probably worse) problems. They don't have to be out by much to show up in the work.

But if your chuck measures 5 thou out, you have to grind that flat first, before you can even think about grinding work on it. Make sure your table isn't what's out before doing that, and make sure its ways are clean, properly lubricated, and move *very* smoothly.

When you talk about mirror finishes, even the smallest thing can be a big deal because the slightest errors are very visible.

Gary

Thanks Gary:

My error on the table its .0005" I am attemping to balance my wheel. I have a balancing shaft but no stand. Any suggestions: It seems I have to order seperate wheel flanges to facilitate changing wheels without going through balancing each time.

I don't know if this is right or not, But I used to work in a molding shop with a seperate tool die company in the same building. The old machinist told me he would dress the wheel Then loosen it once and retighten it. He said that gave him a little but of clearance .....to keep the wheel lasting longer, the part cooler, and the wheel wouldn't load up nearly as easily, he also said it would drag the grindings along with the surface.

any of this sound like it has some truth to it ??

Ok, mine came from Harbor Fright. Mirror finish? Ferget it. Not with this machine, or any other that doesn't have some kind of mechanical traverse. CHeck the wheel for balance, on the inside of the wheel hub are three small weights. If they're evenly spaced around it, chances are it's out of balance. The wheel that came with it, throw it away, you'll never get it to grind smooth.

Chances are if you check the work, what looks nasty won't even budge an indicator, but it does look like hell. Grind the top of the chuck, not much at a time, and be prepared to dress the wheel a couple of times before you get it flat. The lead plugs the wheel pretty well. If you get away with taking .002 off the top before the wheel plugs, consider yourself lucky. Wheels, don't chintz. Even good ones aren't that expensive, and they make a world of difference. But with that machine, you aren't going to get a mirror finish with anything other than a buffing wheel and lots of time.

Ah, that extra zero makes a big difference. :-)

All you need is a couple of knife edges. Literally. If the wheel isn't too heavy, a pair of single edge razor blades or utility knife blades will do nicely. Just knock together a stand out of wood and embed the blades so their edges are parallel and level (parallel isn't real critical, level is, incorporate an adjuster foot). The wheel will stop heavy side down. (duh!)

I've seen a cute flange that incorporates a couple of weights on threaded shafts (at right angles) to balance the wheel. But I'm a bit dubious of that when spinning at high speed. If the adjustment goes out of whack, you've got a bomb in the making.

Good flanges, true and balanced, with a good wheel, should work fine without any gimmicks. If you need a gimmick, something's far enough out of whack already that you need to have a second thought before spinning it up.

Gary

Or some finish similar to the one on my mag. chuck. I