Surface grinder wheel

[Charlie Mike]

Its gonna be time to replace mine soon. 7" x .5"

What do you recommend? I have a dry grinder.

 

[kuraki]

Hopefully Don won't mind, his photo from a recent discussion.



Otherwise a radiac of similar structure. You want an open grain, that breaks down rather easily.

 

[Geoff Flato]

I've been using the CGW equivalent of that wheel. It works better for knife work than anything else I've tried

 

[Geoff Flato]

In CGW and Carborundum, it's the pink wheels. And you'd want 46 grit.

 

[Charlie Mike]

Purchased

 

[golfer1]

How do you use those grinders to work on knives. I have two of them and never even thought of using them on a knife.

 

[Geoff Flato]

Turning hot rolled into precision ground stock, grinding the thickness of the tang to exactly fit a milled guard slot, stripping mill scale, ect
Fixed blades it isn't the biggest deal.
But for folding knives it's a huge help.
I've been working on liner locks lately. The blade should be 20-30 thou thinner than the backbar depending on how much clearance you need for pivot bearings. Stick your blade and backbar both on the mag chuck, grind them to match. Pull the backbar off, and grind 20 thou more off the blade. Takes all the guesswork out, and is a lot faster and easier than trying to take parts to a dimension seperatly

 

[Charlie Mike]

For me, it's about getting things clean and flat.

 

[kuraki]

How do you use those grinders to work on knives. I have two of them and never even thought of using them on a knife.

A surface grinder is the best tool available for making blades flat and parallel. "Flat" and "parallel" being relative terms. A bar that has been flattened to clean up on a disc grinder is flatter than it was. It's not as flat as a surface ground bar. There's no other tool in the knife shop capable of achieving similar parallelism as a surface grinder. Parallelism isn't as critical on fixed knives as folding knives, but it sure makes life easier for even fixed blades.

It's a machine capable of making hardened steel flat and parallel to less than .001" deviation, with an excellent surface finish that can either be left as is or go straight to 400+ plus hand sanding, that can taper tangs with perfect symmetry, or allow the removal of material in .0002" increments when fitting a guard. If I had 2 I would use them on every knife.

 

[Charlie Mike]

Originally, I bought one to fix small warps. There was quite a learning curve. Eventually I learned how much to take off from one side, where the heat buildup would cause the warp to straighten out.

 

[golfer1]

Are we talking about those hand held 4" wheel grinders?

 

[kuraki]

No.

 

[javand]

That's a strange handwheel setup kuraki.

Every surface grinder I've ever used that had a handwheel at the spindle was for Z feed. Unlike a mill that usually has a knee that moves up and down, most SG's have a spindle that moves up and down, and the middle handwheel at the table is Y. Many bigger units, like my Landis hydro feed, has all three wheels at the waist, X, Y, Z in that order, left to right.


Is that diagram just mislabeled? Seems like it would be awkward as hell moving Y with that upper wheel.

Off-topic I guess, just struck me when I looked at it.

 

[Geoff Flato]

I've seen a few different configurations. My dad's doall is as you described, but my G&L #15 is a knee type, middle handwheel pointing straight out is Y, the left handwheel points out at a 45 degree angle and moves the knee, the right handwheel points out at a 45 in the other direction and is the traverse. Spindle is fixed in place on the casting.
I'm not sure that I've ever actually seen another knee surface grinder.
I've seen the traverse handwheel on both the right and left sides on various machines.
But as you say I've never seen the Y up there before