I recently bought one of these and am pretty impressed with how it went together. Thought it was worth sharing.

The kit comes in a flat rate box. It consists of a series of laser cut chunks of plate that bolt together to form the grinder base.

You have to supply or make your own wheels, contact arm, motor and bolts...

As built I have about $400 in this... Used a 1 1/2HP 1725 motor that was salvage (I think If I build another I'll use a 2HP + 3 phase motor and a VFD)

It comes with a rotating platen chunk but I chose to set this up with a contact wheel since I have other grinders with platens.

It wouldnt take much to build your own wheels but I chose to buy mine...

I bought a 10" contact wheel from Grizzly
Grizzly 10" wheel

and the Drive and tracking wheel from USA Knife maker supply
USA Knifemaker

The kit is available from Jamie at Polar Bear forge
Grinder in a box

If you order one, Tell him you read about it here, I am trying to get him to donate a kit to our Knife making school and if he sees some support It would be helpful!

Nice bit of kit there.....have fun with it!!


alec

Looks good Larry I watched the guys on another forum come up with that after getting ripped off by another guy... crappy start with a neat/positive ending.

I've got 2hp with VFD on one of my KMG's and it's definitely got a lot more snoot than my 1.5hp Burr King. I've got 3hp on the other KMG I really do think more is better!

What's this about a knife making school???

Dave Lisch rented some space to have a school. Tom Ferry is on board and I am going to try and help round up equipment. They have some pretty big names lined up and I think it's going to b a great thing

the school sounds interesting... i think i might try the grinder kit in a box ! ive got a homemade but not near as versatile...

I tell you what... I have a variable speed Square wheel, and a Burr King with the knife maker attachment... And the Grinder in a box is my new go too grinder... I am really pleased with its usable and adjustable base and tooling is quick and simple to build. I am thinking I might buy another

Larry,if you do buy another you might want to think about putting one of those 3 phase motors I`m sure you or your Dad have cluttering up the back room on it and spending the money you saved on a VFD.
One warning though,once you try it you`llbe wanting to switch all the other motors over so buy a larger VFD and put it on wheels so you can move it around.
Nothing beats having infinite speed control while still retaining power in the low RPMs.
Wish I had known about VFDs before I started buying DC drives.

How did you know about my Dad's back room? You been out his shop? My Dad's "back room" is a scroungers paradise... Hundreds of new in the box three phase motors are the least of it... And yes I had planed on doing just that, its one of the reasons I think a second machine is in order. The 1.5HP 1725 on this machine grunts pretty well but having the VS square wheel has shown me the benifit of having the control. And like you in the past I went DC because its what I understood...

Only thing about those VFD's I don't like is that you loose torque when you lower the RPMs.

They still have alot more grunt in the lower Rs than a DC.
I can stall my 2HP DC Conover lathe at low RPM no problem.Try that same trick with my brother`s lathe,same RPM with a VFD and the same HP motor and you better be ready to turn loose of it. :o

Larry, thanks for sharing the pictures of your build. We'll keep in touch about one for the school.

All my grinders so far have been single speed. My solution (no way to use vfd in my old shop) was just to build more grinders.

Jamie

Should be able to maintain a pretty flat torque curve with any decent VFD. Unless you mean compared to "gearing down". OK, I got the real deal! 3 X 120 tandem machine with independent 7-1/2hp motors. With 36 grit, I don't get sparks, I get a sheet of pure hyperthermic nuclear plasma.

What can I say? I got big industrial size toys! "Igor! More Power"! Kinda look funny now that I don't have a big industrial size shop. You should see my saw! 18 X 18, guillotine action, 1-1/4" X 15' blade, 0 - 500 fpm. fully automatic! I've cut through 16" 50Rc die blocks.

ya but can it cut a car in half like the lennox sawzall blade thats only 3/4"X10" long :lol:

Sure I can! I just gotta forge it down to 18 X 18 first so I can get it in the saw.

OK, I got the real deal! 3 X 120 tandem machine with independent 7-1/2hp motors. With 36 grit, I don't get sparks, I get a sheet of pure hyperthermic nuclear plasma.

Now Grant,you KNOW we want pics of THAT!!!

Now Grant,you KNOW we want pics of THAT!!!

Pictures Ha, I wanna come watch!!!!! I'd even bring the car :P

Yeah Grant has the biggest saw I have even seen in a one man shop.... Is very pretty... Pretty sure it could cut my saw in half without much effort

Larry,

I'm building one of these grinders in a box, and I also got a 10" contact wheel from grizzzly.

I'm wondering, how did you set up the bearings for it?

I machined pockets in either side of the wheel and set roller bearings in... If I had it to do over I would put the bearings in the arm and hard mount the wheel on a spindle....

Thanks, that at least points me in a helpful direction.

I'm not sure if I can do the bearings in the arm, since I'm going to use the multi-platen. But then, my only experience with adding/replacing bearings of any kind is the bronze sleeves and babbit from my forge blower. I don't even know what type of roller bearings would be appropriate.

Well the ones I used where nothing special... Just off the shelf sealed bearings.... I have a lathe so it was pretty easy to machine the wheel... You could have a separate arm for the contact wheel and multi platen... thats what I would recommend... Quicker to change out

Actually, I intend to use it like this:



If you put a roller bearing on each side, what was in the middle? Did you just leave it empty?

I machined a pocket in either side so the bearings would push in but be separated by the material left in the middle... You cant suck a bolt down on the bearings in that configuration or it will seize... I just used a bit of lock tight on a loose nut and have never had any issues...