how to dress tool post grinder wheel?

Any way you can mount the diamond so it functions would be acceptable. Keep this in mind.:

Mount it at such an angle that rotating it will present a sharp edge. Angling it downhill at 10 degrees would work. Use your diamond in such a way that you don't wear a rounded tip, rendering it less than useful. Sharp corners of a diamond are far better than a round point when dressing a wheel.

Use a diamond in such a way that it can't "stub". If you angle it upwards, rotation of the wheel, assuming it's running downwards on the diamond, isn't a good way to go. Also, because the wheel is rarely truly at a right angle to the spindle, both the diamond and wheel should be on the centerline in order to dress the wheel surface parallel to the work surface. Angle of the wheel makes no difference if you're on center, assuming you don't use the side of the wheel to kiss a face. In that case, angle is critical.

Best is to avoid using a toolpost grinder. They are a miserable choice when compared to a cylindrical grinder, and should be operated dry. Dry grinding leaves a considerable amount to be desired. Overall, they perform poorly, but they do permit working on objects that, otherwise, may be beyond your ability to machine.

Be careful to fully mask your machine to minimize the amount of abrasive that will accumulate on critical surfaces. Lathes aren't made to be exposed to such contaminants, and suffer considerably when so exposed. Do not attempt to use coolant. That will spread abrasives in all directions. Not a good idea.

Harold

I just pinch the dresser between two chuck jaws, but you have to do this before the workpiece is in the chuck.

Jon

We had a tool that looked like a C clamp. It had the diamond dresser mounted in a hole so that it pointed at the wheel. We clamped it on the part to be ground. Just like Harold said, the whole setup, grinder and dresser was a poor setup all the way around. We could get a better finish with carbide tools for what we were building.

Don't know what the usual method is, but my intent is to make up a square channel-shaped gizmo to bridge the cross-slide and long enough to lay across the ways, then use a regular diamond dresser jig like you can get for surface grinders and the like. Height of the combination will be somewhat critical. Might even be able to make do with good plywood or something like polycarbonate. I've got a lot of thick Lexan cutoffs, myself.

Re: other posters comments: Specialized grinding equipment is great if you have the bucks for same and no doubt a whole lot better to use in a production setting. For the rest of us that only need to do grinding once in a blue moon and/ or don't have room for cylindrical grinders and such, a tool post grinder has to make do.

Stan

Well ... I don't have one, but I have seen holders which clamp around the workpiece and hold the diamond dresser. Obviously used with the spindle stationary. :-)

Enjoy, DoN.

Don't know what the usual method is, but my intent is to make up a square channel-shaped gizmo to bridge the cross-slide and long enough to lay across the ways, then use a regular diamond dresser jig like you can get for surface grinders and the like. Height of the combination will be somewhat critical. Might even be able to make do with good plywood or something like polycarbonate. I've got a lot of thick Lexan cutoffs, myself.

Re: other posters comments: Specialized grinding equipment is great if you have the bucks for same and no doubt a whole lot better to use in a production setting. For the rest of us that only need to do grinding once in a blue moon and/ or don't have room for cylindrical grinders and such, a tool post grinder has to make do.

Stan

Yes, Stan. I agree. It's just that if you can avoid using a tool post grinder, that's always the best policy. I more or less alluded to that in my post.

I had to run a pair of tapered plug gauges (defense job) when I worked at a job shop that was not grinding oriented. They were turned, heat treated, then ground using a tool post grinder. Having spent a few years in the aero-space industry as a precision grinder, the task was quite distasteful, and were it not for my killer instinct for producing fine work, they wouldn't have turned out well. As it was, they did, something I've never forgotten, nor have I forgotten the hoops I had to jump through to achieve success. Clearly, a tool post grinder has to be one of the worst tools ever invented. The only thing going for them is that they do grind--------------how well is up for grabs.

Harold

The only problem I saw in my minds eye with clamping something to the ways is the carriage will be in the way. Something long and a little unstable might produce some vibration in the dressing tool causing some inconsistency in the wheels face.

Clamping the dressing tool short and rigid is important.

I understand having to use what you got. I read where someone said, "Desperation is the mother of invention."