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Alistair Hosie
05-08-2006, 07:29 PM
I bought a small diamond wheel dresser but want to incorporate it in a stand to slide beneath the wheel as last time I did the wheel freehand I was a bit too shaky anyway what angle shoulld it be regards Alistair

CCWKen
05-08-2006, 08:07 PM
I read somewhere, IIRC, that it should be about 3-5* off center line but I'm not sure that it matters or if that's correct. The radius dresser tool I have needs to be near dead on to register correctly and the TP grinder-dresser works the same way--On center.

TECHSHOP
05-08-2006, 08:07 PM
I have been using this a a reference:

http://www.woodcentral.com/cgi-bin/readarticle.pl?dir=jigs&file=articles_576.shtml

hopefully that linky will work, if not I explain this:

http://www.woodcentral.com/

then click this: Wood Central Articles & Reviews

then look for this: Extending Diamond Dresser Life--Proper use

In the interest of full disclosure, the man that runs this site is "local" to me, I have met him a few times, but I don't think he would know my name if we passed on the street.

big-dipper
05-08-2006, 08:23 PM
I was taught the diamond should be close to centerline of the wheel, and at a negative rake angle. I'm no grinding guru though. Someone with more grinding time, that uses a diamond regularly, might have more advice.

CCWKen
05-08-2006, 09:13 PM
Okay..... So it's 10-15* angle downward with the point ON Center. :eek:

That still doesn't work with the radius dresser. It's point holder is a 90* right angle to the center line. Whut up wit dat?

greywynd
05-09-2006, 02:42 AM
The reason that a diamond is generally a negative rake and slightly below centreline is safety, if the diamond grabs it will be pushed away from the wheel rather than into it (which can get messy.)

A lot of diamond holders use a 10-15 degree angle, by loosening the clamping screw and rotating the diamond a part turn will give a fresh edge to the diamond.

In the case of a radius dresser (or when dressing a fussy angle for that matter) being on the centreline, and 90 degrees to it is the only way to get the proper form. On fussy profiles we'll use a piece of razor blade held in a grinding vice (shim stock or a piece of graphite will work too) to grind the profile in after dressing the wheel, then it can be checked on an optical comparator before the actual part is ground. You do have to be careful with the amount of feed, the diamond can grab.

Another time that the diamond is close to the centreline is when relieving the side of the wheel for sidewheeling. When doing this however be careful, because if the diamond goes too far, it will run into the wheel being left behind, and may grab.

Mark

Scishopguy
05-09-2006, 06:09 PM
When dressing the wheel on a surface grinder you can place the diamond anywhere from the true center to slightly behind center and be safe (providing the feed rate is not too much). I usually feed down .005-.0015 per pass. You can make a little angle fixture with a cutaway on the back side to slide the diamond holder across to dress your angle. If you try to take too much the holder will simply be pushed off the back of the jig, as long as it is at or behind the center of the wheel. I have used this method for years without any problems.

The surface grinder is the scarriest machine in the shop as far as I am concerned. If the diamond is on the infeed side of the wheel you can easily break the wheel. That will ruin your day. If you forget to engage the magnetic chuck, that will also ruin your day. Many a part flew off the chucks and up the dust collector chute at the place I learned my grinding skills.

Jim (KB4IVH)