surface grinder or ?

[22H2]

what is the best tool to flatten steel for folders? I know a surface grinder is probably the best answer. I was wondering if somone had a different ways of doing this.

thanks

[Ray Rogers]

Surface grinder is the best way, that's what they are made for. There are other ways though. The easiest and surest way is probably to buy precision ground stock to make your blades from. If you buy an air hardening stainless and have it heat treated in an oven by Paul Bos or Texas Knifemakers then clean up will be easy and you won't lose much metal. Remember that on a folder the only portion of the blade that must be flat and parallel is the tang area around the pivot so, if you start with PG air hardening steel, you won't have much to worry about ...

[Messinger]

Ray knows his stuff.

I'll add that it would be a good idea to get a granite surface plate. You can often get them from Enco for as little as $14 (at least I think that's what I paid). The surface plate is ground precisely flat. Placing a piece of sandpaper on it gives you a good surface for flattening all sorts of folder bits (blade, spine, bolsters, scales).

Where a surface grinder helps is not only making things flat, but making opposing surfaces parallel. You can do the same by hand with a surface plate, sandpaper, and a micrometer - it just takes a little longer.

-Ben

[22H2]

thanks
I have notice in some tutorials that a disc grinder can be used I was wondering if this would be better than using the platen on a 2 x 72 inch grinder?

[Ray Rogers]

Some guys seem to think so but I've had two 12" discs and find them to be nearly worthless for metal and not too impressive on wood either. Probably all in what your used to but for myself I'd choose a glass covered platen over a disc any day.

BTW, Ben had a good point about the granite surface plate. I also have one which I paid $40 for from Harbor Freight and they're great for sanding. Considering that you have such a small area (the tang) that needs to be 'surface ground' you probably could get the job done that way with care and practice...

[22H2]

thanks Ray and Ben

[Messinger]

Sure. : )

I wanted to add that like Ray I had a terrible time at first with my disk sander. However, I found that it was mainly due to the disk surface not being true. I made a stubby arbor in my own small lathe that would hold the disk, then I took the disk+arbor to a machine shop and had them chuck it up and face the disk for me in a big lathe (my mini-lathe was way too small) and now it works very well.

Where I find the disk sander to work better than the belt is flattening objects that don't have extra material around the edges. I find that the belt lifts the edges (probably because the belt bunches-up a bit at the edge of the piece being sanded). The center of the object will be sanded flat, but placing it against another flat surface I find gaps at the edges. This happens to me to a much lesser degree with the disk, probably because the paper is glued to the disk and can't bunch-up (picture how a rug will sometimes bunch up when you slide a piece of furniture across it).

For me the way around the edge problem when using the belt is to have plenty of extra material around the periphery of the work piece. Sand it flat, then turn it and grind back the edges a bit. Doing this reduces the size of the piece, but leaves you with the flatness you need.

I hope this helps. I'm not very experienced, but these are some things that have helped me.

-Ben

[22H2]

Ben, that is what I found as well, I was trying to flaten some ss and could not get the entire piece flat the middle would be flat but the edge would have a slight taper. I may try a disc from Beaumont and build my ouwn grinder.

[CWKnifeman]

You can also use a mini-mill as asurface grinder, using a magnetic chuck and a 62 Rockwell cone stone. before I got my mill I learned how to surface on my flat platten usign a flat push stick with a pin to fit into a pin hole.Did that for many yearsyou can get really good at it. One of my friends asked how I was doing it, I dod one on the mill and one with the push methosd bnoth were 0.0005 true to size.

[22H2]

thanks Curtis I thought about that, I have a mill drill but I have a dedicated vise that weighs about 80 lb mounted on the table. do you think the mill would be quicker than surface grinder?

[CWKnifeman]

Probably about the same, time wise.