Knife Maker Belt Sander Recommendation?

[Frank Ford]

Whew! I spent the most of the day at my combo 6x48, 1x42 sander, cleaning up that bunch of horseshoe magnet pieces, and finally buffing them for plating. Since this appears to be an ongoing project, I think it's time to upgrade, most likely to a 2 x 72 setup like knife makers use. I've often thought about making my own, but I need to be able to put it to work, and it looks like my time will be too short for at least the rest of this year.

So, without regard to price, what's the best rig from the standpoint of overall quality and versatility?

The Burr King 960-272 looks appealing online, and it seems to have good reviews. It isn't cheap, but then, neither are my silly little horseshoes.

Others I should look at?

[Hal]

Frank

Check out the KMG grinder web site.
Its quite a machine.

Hal

[Doc Nickel]

Definitely a KMG Belt Grinder from Beaumont. From everything I've heard, Rob's very helpful and friendly, and his products are top-notch.

I'm making a "clone" from plans available online, and I'm looking forward to getting it up and running.

If money is little or no object, spring for the 2HP variable speed, and get at least the flat platen and the 10" contact wheel. It's not cheap, but like those Baldors we were talking about a while back, it's worth it for the quality and power.

Doc.

[Michael Hall]

Doc

Do you have a link to the plans that you are using?

Michael

Definitely a KMG Belt Grinder from Beaumont. From everything I've heard, Rob's very helpful and friendly, and his products are top-notch.

I'm making a "clone" from plans available online, and I'm looking forward to getting it up and running.

If money is little or no object, spring for the 2HP variable speed, and get at least the flat platen and the 10" contact wheel. It's not cheap, but like those Baldors we were talking about a while back, it's worth it for the quality and power.

Doc.

[gwilson]

I have the Wilton Square Wheel belt grinder. I think it is about the most versatile grinder out there. They have gotten so high,though. $2500.00? Mine is variable speed,which is a very valuable asset when you are putting the last touches on a blade. Makes it easier to get the blade back on the belt without grinding a little dollop out of it.

It has an 8" contact wheel. I wanted a larger diameter wheel,so I made a block of steel up with a large radius curve ground on its front. The block is about 3/4" thick. I welded a clamp on the back of it to clamp it to the flat platen. The belt goes right over it. It works great. I can grind knives with a much flatter hollow grind to them,like they had in the 19th.C..

[Doc Nickel]

Do you have a link to the plans that you are using?

-Easy enough, just Google "KMG plans" and you get this link. (PDF, fyi.)

They're not perfect, I've noticed a few very minor flaws here and there (mainly things like an omitted dimension) but they're very good. They're basically just "blueprints" for the frame of the grinder, though- there's nothing about things like left/right spacing, drive wheel sizes, motor placement, or anything like that. It's basically just how to build the raw carcass.

Doc.

[Bob D.]

Ditto on the Square Wheel. I bought mine years ago with the intention of grinding knives, but now I used it quite frequently on a wide variety of parts. I replaced the single speed AC motor with a Leeson 1HP PM DC unit and a Leeson Speed Monitor controller. Very versatile machine; I usually have the square wheel in place rather than the conventional contact wheel.

I never got the hang of grinding symmetrical profiles on both sides of a blade blank. After ruining a lot of steel I tried practicing on similar size wood slats with little success, I guess I just don't have the knack

But I don't regret buying that grinder!

[Your Old Dog]

I've had a Wilton Square Wheel but think I'd prefer the KMG. There's a reason that 9 out of 10 knife makers have more then one of them. I think for one thing the KMG would be much quieter in operation. I didn't have a variable speed motor on my Wilton and don't really see the need for one. Just built a KMG styled grinder without variable speed and have no problems.

I would encourage you to get a few 500 grit cloth backed belts and when they wear out you can run them inside out with rouge for some great buffing.

The kMG is more versatile in options available to it and it changes over from one option to another much faster.

I would encourage a serious effort at dust control. My wilton made a mess of my basement !!

[lakeside53]

I looked at the commercial designs. The KMG is nice, but having more time than money, I decided to build my own. Having the time... it's turned out to be the "shopsmith" of grinders. Mine's based on the plans for a "unigrinder" (still available) but it's now moved away considerably. The unigrinder plans seem to be based on "if you can weld, you can make this"; mine - "welding is great but I prefer to machine". It's 3hp vfd driven, and goes up to 6000 sfm with ease. It has a display that shows sfm/rpm; just frills, but nice to have. A lot of design and machining work to get it perfect and it takes a long time if you start with random chucks of scavenged metal and make pretty much everything except the bearings from scratch!

Variable speed is very nice. It's amazing how well a belt will cut steel at high speed, but you need to slow it down for the fine grits. Even with a 220 grit belt, there is a big difference between 3000 and 6000 sfm, BUT, a ceramic backer is desirable if your going to run fast and need to pay attention to bearing speed (heat, life..). Ceramic backer -just a piece of wood stove neo-cermam (not plate glass) - I had one that was broken; the replacement for my stove cost a fortune, but I kept the old pieces - made 4 backers and have enough left over for 4 more!. Sure better than buying them.


Oh.. I have a few hundred hours invested in the 2 units (a joint project with Metalmagpie). All I have to do now is stop using them, package the VFD/input switches, and final paint...

Build pics up to 2 months ago are here (I need to upload a lot more, but I'll put the link here anyhow and get the upload done in the next few days.

http://s238.photobucket.com/albums/f...elt%20grinder/

Here they are as at a couple of months ago both with 8 inch contact wheels (from Contact Rubber Corp):


Platen assembly - neoceram backer; this section removes (4 SS button screws) to make a "slack belt". The table is one of several different that will be used - the others will mount on the 1 inch rod that protrudes beneath the main support.





General purpose 5/8 -11 thread, 3/4 arbor. Wire brushes, buffing etc. Polyvee belt drive direct from the rear pulley (not via the tracking mechanism). There is a bunch of spacers, flanges washers, 5/8 and 1/2 adpapters not shown. I can stack up to 2 inches of buffing wheels, or put a 12 inch disk on the arbor end. Need to watch that rpm meter though...

[AlexK]

Great job lakeside53!
Your little platen table is very smart design. I'll probably "borrow" your idea if you don't mind and make something like that for my KMG. Standard KMG table is not very convenient.

My KMG is 4 years old and I like it a lot. Two years ago I've upgraded it to 2HP motor with VFD. It was somewhat costly but was absolutely worth it.


BTW lakeside53 where did you get your neoceram platen?

[lakeside53]

It's from my old woodstove. You can buy them for about $20 ($2+ a square inch!), but the available size wasn't to my liking. It cuts like tough glass, and you can use a std belt on your grinder to dress the edges.

Walk into your local glass supplier - they might have off-cuts or broken ceramic that can be trimmed to your size.

I bonded the neoceram with JB weld to 3/8 thick aluminum angle (great heat sink!). Both turned out perfect, with no bubbles or voids - work from one edge, use the wheels as a reference on a flat surface, lightly clamp it to the mount surface and let gravity "set" it correctly w.r.t. the wheels.

[Plain ol Bill]

I make a lot of knives. I have a grinder I made myself using the Unigrinder plans. I later bought a KMG then a horizontal grinder made by the KMG maker. I use the KMG a lot more than the one I made myself and it was a good investment. I highly reccomend variable speed and you will wonder what you ever did without it when you get one. I use my grinders for everything in the shop as well as sharpening pencils on them!
It is my opinion that the folks that make and sell belts should furnish all shops with a free grinder. They would make it back in belt sales shortly.

[Frank Ford]

Well with that much of a consensus, I guess I know which machine to get - thanks everyone.

[dp]

I've been seeing a lot of chatter in the guitar groups over Jason's horseshoe pickups - they should sell well.