Dressing a wheel

[Mayhem]

Vinny's recent post about the hardship he had to endure to equip himself with a surface grinder reminded me that there is one question that I need an answer to:

Exactly how should the diamond be addressed to the wheel?

I have read that the diamond should be angled 5-10° away from the centreline of the wheel but I am unsure whether this is toward the rotation of the wheel or away from it.  Given the image below, should the wheel be spinning clockwise or counterclockwise?


  dressing_a_wheel.JPG (Size: 20.06 KB / Downloads: 107)

[rleete]

Not sure about a shop grinder, but our big industrial grinders here at work have the diamonds on the centerline and perpendicular to the CL of the wheel. Never heard about angling the dresser, ever.

[Mayhem]

I had figured there may be a 'dig in' risk but on a machine that is designed to take minuscule amounts off I'd expect that this wouldn't be such an issue but I've never run one before.

I've watched Ken use one but I didn't really pay any attention to the dressing part, as I figured that I'd never find a surface grinder here that didn't cost more than the car I drive... I guess I'll have to pay him another visit

[dallen]

the grinder I used at the school this fall has the diamond in line with the center of the wheel, I would think that if your going to angle it that it would be away from the rotation of the wheel so if something happens that it would kick the dresser out away from the wheel.

BUT I may be totally wrong.

[Sunset Machine]

I do that with "dig-in" in mind, but I really think it's so you don't damage the tip. Point it down stream and just past the wheel center. Rotate it in the holder once in a while.

Dunno how you'd get it on center, eyeballing across 3-4 inches like that. Just past center seems safe.

[Highpower]

According to Machinery's Handbook:

Quote:Guidelines for Truing and Dressing with Single-Point Diamonds.—The diamond nib
should be canted at an angle of 10 to 15 degrees in the direction of the wheel rotation and
also, if possible, by the same amount in the direction of the cross feed traverse during the
truing (see diagram). The dragging effect resulting from this “angling,” combined with the
occasional rotation of the diamond nib in its holder, will prolong the diamond life by limiting
the extent of wear facets and will also tend to produce a pyramid shape of the diamond
tip. The diamond may also be set to contact the wheel at about 1?8 to 1?4 inch below its centerline.

[Vinny]

I remember dressing the wheel on the grinder back in high school (over 40 years ago) but after you asked this I can't for the life of me recall if the diamond was angled or how I would have got it on the center line. My old shop teacher is on Facebook but I can't ask him. I dressed a wheel on an angle once on the cylindrical grinder and pissed him off. He still won't talk to me!

[TomG]

Darren,

Angled or not, what really matters is that the dresser is positioned past the center line of the wheel. That way when you forget to turn on the chuck (and you will), the dresser will just tip over rather than be propelled across the shop.

Tom

[Mayhem]

(11-13-2015, 09:04 AM)TomG Wrote: Darren,

Angled or not, what really matters is that the dresser is positioned past the center line of the wheel. That way when you forget to turn on the chuck (and you will), the dresser will just tip over rather than be propelled across the shop.

Tom

So to the left of the wheel? I'm a visual person, I need to see it...

[Dr Stan]

(11-13-2015, 09:22 AM)Mayhem Wrote:

(11-13-2015, 09:04 AM)TomG Wrote: Darren,

Angled or not, what really matters is that the dresser is positioned past the center line of the wheel. That way when you forget to turn on the chuck (and you will), the dresser will just tip over rather than be propelled across the shop.

Tom

So to the left of the wheel?  I'm a visual person, I need to see it...

Assuming clockwise rotation on a surface grinder (I've never seen counter, but one never knows) (maybe in Austrailia or New Zeland as you face the front of the wheel, yes.

When dressing a cylindrical grinder or tool post grinder it should be below center just like the diamond dresser I use on my bench grinder.  Tool & cutter grinders are a different beast.  All depends on the shape/type of wheel and the set-up.