A new knife grinder

[Von Gruff]

I have always enjoyed making my own knives and lately it seems I have been doing more than I ever thought I would, with some now going to others, so it started to seem as if my little handyman grinder attachment was not quite up to what may be required of it. I have seen the really nice 72 inch (expensive) grinders that the guys have on the knife makers forums but being somewhat of a do it myself tightwad I wondered if I could cobble something together that would be just as effective.
Aboiut 40 years ago I bought a little dyco saw bench that I gave to my father when I moved up to a better model and when he died I got it back and having no use for a small saw bench I converted it to a sander.
The large drive pulley was replaced with a small one and with the two bench top bearings in place, I got a length of shaft and a larger pulley to slow the output down. To mae the drum I got a piece of 3/4 play and cut a circle then a number ofthers with only an inch in from the outer dia to make the drum. It worked very well but it no longer gets much use so decided to use it for the base of the new grrinder.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0053_zps6vuhpcdf.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0053_zps6vuhpcdf.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0054_zps9fdsvwww.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0054_zps9fdsvwww.jpg.html)
With the drum off and the top cleared it looks to be a good place to start
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0055_zpskog2dz9p.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0055_zpskog2dz9p.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0057_zps46c2pird.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0057_zps46c2pird.jpg.html)

[Von Gruff]

In a dedicated effort to save money I decided to make the drive wheel from hardwood as I had some Jarah in the rack.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0068_zpsk5z0k4po.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0068_zpsk5z0k4po.jpg.html)
A 11/16 slice
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0073_zpsjjxkkvg5.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0073_zpsjjxkkvg5.jpg.html)
Through the thicknesser to bring it back to 3/8 and sawn to 4 1/4 in wide then cut into 4 1/4 in lengths
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0074_zpsmahfmyie.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0074_zpsmahfmyie.jpg.html)
With the pieces laid with the long grain alternating, they were glued up cramped
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0075_zpsizrmeywg.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0075_zpsizrmeywg.jpg.html)
The thick (and hard) block needed carefull cutting to get a good 4 in circle which will become the drive wheel
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0076_zpsoezppwm9.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0076_zpsoezppwm9.jpg.html)
I didn't get a pic but a plate was cut and drilled for the 1/2 end on the shaft it will run on and bolted to the drive wheel. It is down at the garrage for the guy to weld the plate to the shaft and turn the drive block to a true to the shaft round and then I can crown it when when it back on the grinder base.

[Von Gruff]

I found a really good set of plans that will allow me to make something very close to this one here.\
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Grinder%20example_zpsb2t4nphd.png (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Grinder%20example_zpsb2t4nphd.png.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Grinder%20example%202_zpsklsrlger.png (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Grinder%20example%202_zpsklsrlger.png.html)
I got a great deal if information from this web page
http://dcknives.blogspot.co.nz/p/2-x-72-belt-grinder.html

Things will have to sit for a bit as I need to get into the city to pick up some steel and for the other needed wheels and and some 72in belts to arrive.

[Blackwater]

Nice work, VG! Love to see folks doing things themselves. Reminds me of the old 'smiths that put together the old PA & KY rifles so long ago with little to nothing to go on. I have Dillin's book, wiht good pics of some of the old rifling and other machines, and they were all built of wood with very little metal used because there simply was very little of it TO use. "Where there's a will, there's a way."

When it comes to grinding knives, though, I'm afraid I got spoiled. Used a Burr-King. MUCH quieter than a Square Wheel and I like the quick adjustments and very rapid availability of either flat or wheel grinding. I guess I never should have touched one of those?

But in th end, it's really not the equipment, but the craftsman in question that matters most. Each of the old riflemakers in the PA/KY era had their followers and advocates. Sam Hawken surely had the notoriety, but many others were involved as well. Variety really IS the "spice of life."

[Von Gruff]

It all comes down to the available dollars in hand and with next to none of those I revert back to the old adage that has been the cornerstone of most of my little projects when wants outrun income and that is "how can I make one of those"?
I have been lurking on a couple of knife forums for a while and seeing some of the best of the grinders going for up to $3000 and even the cheaper end of the ready builts or kit grinder is spending money that could be saved for those things I cant do.
I have a friend who is a full time knife maker and seeing his equipment and the ease with which he has fabricated some of his grinders (he has four that are permanent set-ups) makes it a no brainer for me to do this one. While it may not match the top of the line models it will still do all I will ever need with much more versatility than the little 2x36 that has sufficed up till now.

[BigEyeBob]

A bloke has to do what he has to do .

[nekshot]

You remind me of my dad as he was a master benchman with wood. He left me with a lot of his small speciality tools he made and boxes upon boxes of wood fasteners many of them brass. I was the only son that had woodworking in my blood but he was a perfectionist and I made mistakes as a teen and that separated us in the shop.

[Reg]

Brilliant Sir, just plain brilliant !!!

[W.R.Buchanan]

I made mine in 1984 while working for a company here in Ventura. I was making knives on the side and needed a real grinder and didn't have $1200 for a Burr-king. I bought the main wheel and Idler assembly and fabbed the rest from scrounged parts. The bearings came off a food grade conveyor that was scrapped and have ran perfectly ever since with greasing about every 15 years. I have a Flat Belt Attachment, and a Hollow Grinding Jig that allows repeatable blade contours.

I still use it nearly every day for various grinding jobs in the shop and I used it last night to shape a Front Sight Blade for the Springfield I shot today. I get to do that job again as that blade went winging on shot #17 today.

So far in 30 years only the belts (2x72) and the on/off switch have been changed.

Randy

[Von Gruff]

Looks good Randy. Many different iteration of these have been made in numerous home workshops and work perfectly well.

[Von Gruff]

After a good look in my shed I found some 2x2 box steel that would work for the main stands and with trip to the garrage for some welding was able to do a mock-up .

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0085_zps7nvppelg.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0085_zps7nvppelg.jpg.html)

[Tnfalconer]

How are you planning to control belt tension? Spring inside the square tubing behind the platen? That think looks great so far. Especially since you have found most of the parts laying around house.

[Von Gruff]

I have a small gas strut to keep the belt tensioned. I got some more steel today with the two tool arms (I will need more for some other set-ups later) and the adjuster arm then a foot of 4x1/4 plate to hold the angle iron platen and the idler wheels and a length of 4x3/8 for the tool rest

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0087_zpsm09fbrjw.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0087_zpsm09fbrjw.jpg.html)

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0089_zps21ayf9ix.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0089_zps21ayf9ix.jpg.html)

I need a few bolts but the tracking adjuster is done

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0090_zpswufxabpe.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0090_zpswufxabpe.jpg.html)

Then I changed the use of an old target stand I made some years back (it is no longer used) and with a little cutting off of various bits and adding some box section short pieces it will make an ideal tool head stand

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0088_zpswquzbwny.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0088_zpswquzbwny.jpg.html)

[W.R.Buchanan]

Garry: Your drive pulley needs to have a crown on it and be adjustable side to side to allow for belt tracking. Belt Tracking is necessary so that you can hang one edge of the belt over the side of your main pulley, or in your case the Flat Platen so that you can radius the back edge of the blade bevels. You need to be able to change the tracking easily so that you can bias the belt to one side or the other quickly to do this part of the blade grind. Also the tracking will change as the belt wears or heats up during use.

On a Flat Belt grinder like you are making, you have to do the tracking adjustment at the drive pulley because you can't really do it on the upper or lower idlers as they are generally fixed.

Not sure if you're aware of these fine points but thought I'd make them known so you didn't back yourself into a corner if you didn't know.

I can guarantee that the belt WILL NOT track right on it's own no matter how good your alignment is. It has to be adjustable as no two belts are the same and just using one side of the belt more than the other will stretch it and change the tracking as it heats up.

This is the same theory as a Band Saw's wheels needing to be adjustable for tracking, or a conveyor belt. Making fences to guide the belt doesn't work as it only wears the fence and as the belt heats up from that friction it only makes it worse until the belt finally fails.

Also I assume you are making this thing to use 2X72" belts? They are the most common and have the widest variety of grits and types of any belt size.

The drive pulley's crown only needs to be a small amount like 1/8" high in the center and it can be cone shaped on either side resulting in a high center. The belt will follow the crown. Typically on conveyors the drive pulley is crowned and the idler is flat or I've seen both crowned on conveyors that are really long.

In the pic showing my Idler assembly you can see how the thing both allows for belt tracking and acts as Spring Loaded Tensioner. To make gross adjustments you can see that the entire carriage that the Idler assy. is mounted to will travel on the 2x2 upright.

Anyway it looks like your machine will turn out fine as long as you can figure out a way to adjust the drive end for tracking.

Just to clarify,,, I have to adjust belt tracking on mine virtually every time I use the machine. It changes with the heat of the Day as well as with usage!

Randy

[Von Gruff]

I have been using a smaller (2x36) grinder for over 35 years and belt sanders since the 60's so am well aware of the tracking needs of belt grinders
If you have a look at my second post Randy, I mentioned that I will be crowning the drive wheel and my last post, you will see that I have a tracking adjuster which will be a crowned wheel. I have done a lot of reserch on these grinders and the link I made earlier in my thread to the set of plans with a couple of pics from the link should indicate that I have looked into this quite well before commencing on the build. Being on a couple of bladesmiths forums I have also read a great deal on the good and bad point of the various designs.
It is being built round the 72in belts (again as mentioned at the start of the thread) and I have a selection being sent along with the the crowned adjuster and idler wheels I need.

[W.R.Buchanan]

So you're good to go,,, Glad to hear that. I, like most, don't always read all of a thread especially when there's pictures to look at.

More concerned that you end up with a good final product. So many just dive in and don't pay attention to the details.

Looking forward to seeing it running.

Randy

[knifemaker]

For your 2X72" sanding belts, check out the "Supergrit.com" web site. Great prices on sanding belts and they carry many other abrasive items. I can order on Friday, and have the belts delivered on Tuesday, sometimes Monday.

[Von Gruff]

For your 2X72" sanding belts, check out the "Supergrit.com" web site. Great prices on sanding belts and they carry many other abrasive items. I can order on Friday, and have the belts delivered on Tuesday, sometimes Monday.

I got my first selection coming from these guys as I got some of the wheels etc from them as well.
http://usaknifemaker.com/

I will put your link in my folder Thanks.

[Von Gruff]

Been a busy day and have it all to a stage now that it just needs the drive wheel turned and the wheels to arrive from the US so in a couple of weeks I should be able to get it tunred on. The tool rest will not get welded on till the wheels arrive so I can center the rest against the belt
This is how it sits for now though.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0092_zps2yfwd2zr.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0092_zps2yfwd2zr.jpg.html)
I will drill out the holes for the idler wheels when they arrive
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0095_zps4xg3ttjh.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0095_zps4xg3ttjh.jpg.html)
The handle of an old gate valve made for a good tracking adjuster wheel and a length of pipe flatened and welded to the bolt head will allow for tightening up on the two sliding tool heads.
Here I am holding the tensioner down against the gas ram stroke
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0096_zpsu0ivol9k.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0096_zpsu0ivol9k.jpg.html)
With it released it shows I have a goodly amount of travel
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0097_zpsyxv32xaf.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0097_zpsyxv32xaf.jpg.html)
Then there is the tracking aduster screwed all the way out to track one way
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0104_zpspdsmnnsv.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0104_zpspdsmnnsv.jpg.html)
And all the way in to track the other
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0105_zpsl0wlcmjq.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0105_zpsl0wlcmjq.jpg.html)

[floydboy]

Great thread. Please continue to post pics as you proceed. I like to dabble in knife making and have got to the point I want a grinder that will do a better job. Like you I don't need or want the best but would love to have something like this to play with.

[W.R.Buchanan]

OK that should be more than enough tracking adjustment. I doubt mine has been adjusted more than 1/8" total in it's entire life of 30+ years. It doesn't take much to move the belt.

I highly recommend that you spin the belt by hand the first time to make sure the belt is tracking on the pulleys. If you start the machine and it is not tracking on the wheels is will destroy the belt in an instant and throw the whole mess in your face. BTDT.

Randy

[knifemaker]

Never and I mean never stand in front of the belt when you start up any 2x72 grinder. Most times the belt will come apart at start up and you do not want those belt fragments hitting your face. So far in 10 years of knife making I have never encountered a belt blow up, but I still stand to the side when starting up the Bader111 knife grinder.

[Von Gruff]

Do the 72in belts have a direction of travel marked on them like the smaller 36in belts do?

[knifemaker]

95% of them do have arrows showing direction of travel. Some of the finer grit belts do not. It may depend on what type of connecting joint they have, a guess on my part.

[W.R.Buchanan]

I have had numerous belts blow up at start up over the years. Lots of times the belt is old or has a edge that has been frayed or sometimes the splice gives up. I any event it usually happens during start up and that's why you stand out of the way.

Like so many other things, all it takes is getting slapped in the chops once and you'll learn.

Some belts are directional and some aren't. It depends on the splice and how it's made. Butt spliced belts usually aren't directional. Lap spliced belts are. You don't want lap spliced belts because they have a bump in them that gets annoying in about 3 seconds.

Obviously if the belt has arrows on it,,, it's directional.

One other little fine point. If you look at the pic of my grinder you see there is a little deflector shield over the top pulley. The eblt will carry grinding swarf along with it and when the belt changes direction,,, like over a pulley,,, it will throw the stuff off. Like in your face.

That little aluminum shield peels the vast majority off before it ends up in your eyes, ears, nose and mouth or any other exposed orifice. Grinding Knife Blades is dirty work and is one of the reasons I don't do it very often..

Randy

[Von Gruff]

Again I have to reiterate for those who do not read the posts that already been made, and as mentioned in post #15 I have been using belt grinders for near 35 years and belt sanders (with 12 foot long belts) since the 60's and to be continually offered advice suited to a someone who has never used a belt grinder or sander is a bit condescending

[W.R.Buchanan]

Sorry no intention to condescend,, just offering up info that others might not know. I figure if you've been using these for 35 years you have some idea what is going on, however these fine points are not widely known or obvious and someone coming along without that experience might benefit.

Sorry if I offended I have nothing but the highest regard for your work. Only trying to add content to the thread.

Randy

[Von Gruff]

Have had some good progress with a couple of hours at the engineers yesterday. He turned the heavy collar of the end of the shaft and lengthened the turned portion to take the drive wheel, then turned and threaded the other end to take the disc grinder and leather strop.
With a bit of welding done it is at the stage now that it just requires the wheels and a couple of more bolts to be ready to go.
The disc grinder and with it being 375mm (14 3/4 in) in dia with a 40 grit disc it will be a great asset
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0119_zpskemnhiiq.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0119_zpskemnhiiq.jpg.html)
The smaller disc (doubled 3/4 ply) has a leather strap glued round the edge and loaded with green stropping compound and having already tried it on a knife I am really pleased with how it works.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0120_zps8qifyaxh.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0120_zps8qifyaxh.jpg.html)
On the belt side, there is the platen plate that needs the two idler wheels to complete. The tracking wheel is also needed but these should all be here in a week.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0121_zps2wchglue.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0121_zps2wchglue.jpg.html)
The 300mm (12 in) contact wheel

http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0123_zpsrf387d7u.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0123_zpsrf387d7u.jpg.html)
The small wheel just needs the idler wheel for the lower position and I will have the means to grind the finger curve on the front of the knife handles.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0124_zpsmdyfpvvd.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0124_zpsmdyfpvvd.jpg.html)
The tool head stand will get a length of 3x2 (75x50) fixed on the top with short lengths of 3 in (75mm) down pipe screwed to it to hold the variety of belts
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0125_zpsdrkj9r7m.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0125_zpsdrkj9r7m.jpg.html)

[EMC45]

Super cool!

[Southern Son]

Where did you get the 300mm contact wheel?

[Von Gruff]

China. Great prices (compared to the US sites) with excellent shipping times

http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20160910165010&isPremium=y&SearchText=belt-sander-+crowned+wheels

http://www.aliexpress.com/premium/belt-sander-wheels.html?ltype=wholesale&d=y&origin=y&isViewCP=y&catId=0&initiative_id=AS_20160910164759&SearchText=belt+sander+wheels&blanktest=8

Wasn't able to get the idler wheels there though.

[Von Gruff]

Another little knife clamp made today
A length of 2x2 box, a couple of short lengths of 1 1/2x1/4, a hinge, 2 pins, 2 nuts and bolts and a bit of shoe leather were all that was needed.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0134_zpswigc6oqr.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0134_zpswigc6oqr.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0140_zpshcx2jeyk.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0140_zpshcx2jeyk.jpg.html)
The leather clad gripping arms on top of the box to show how they work
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0143_zpseer0nec9.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0143_zpseer0nec9.jpg.html)
Great for either end of the knife whether vertical
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0136_zpscwlx3l8k.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0136_zpscwlx3l8k.jpg.html)
or horozontal
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0137_zpsycu5lxix.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0137_zpsycu5lxix.jpg.html)
And of course it is invaluable for polishing (or any other work) on the blade
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0138_zpsbdm3tx5a.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0138_zpsbdm3tx5a.jpg.html)

[EMC45]

I'm still very impressed.

[Von Gruff]

Most of the wheels and a few of the belts I had been waiting for arrived so there was a little more progress on the grinder today.
It did take a little while to set up to make sure all the wheels were in the same plane from the edge of the base and thata required a spacing with washers to get it all right but eventually I ran the belt and it tracked true so I was a bit pleased.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0149_zpsdhckhmwa.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0149_zpsdhckhmwa.jpg.html)
Having it running true I crowned the drive wheel the simplets way by glueing a 1/4 in strip light leather round the center point of where the belt ran then covering it with another strip of 7/8 in to effect a rudimentary crown that does work well.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0145_zpse9l92f2k.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0145_zpse9l92f2k.jpg.html)
Getting the platen plate wheels sorted was next but that now tracks to the same position on the tracking wheel as the big wheel so it all seems to be working as intended.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0144_zpso8ghatea.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0144_zpso8ghatea.jpg.html)

There is a replacable platen plate that is bolted to the angle iron backer so that it can be changed out as and when it inevitably developes wear patterns.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/DSCN0148_zps8y4zpjpi.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/DSCN0148_zps8y4zpjpi.jpg.html)
There is only the first few belts that have arrrived at the finer end of the spectrum from 120grit to 600 but there is a number of 40 and 60 grit on the way along with another set of idler wheels, one of which will be for the lower part of the small 1 inch wheel for doing the front curve on the knife handles.
I gave the disc grinder a run and it is all that I hoped it would be so along with the leather stropping wheel I think this is all about ready to be put to work.

[Buck Neck It]

What is the rpm of the motor you are using?

Good idea using an old table saw as the base. "Contractor" grade table saws seem to have no value where I live. There was one at the dump last week, I am going to have to fish it out.

My wife will kill me for starting another project.

[Von Gruff]

I believe it is 1450rpm or so the engineer said when I was there last week and running from the 1 1/2 in pulley on the outshaft through a 6 in pulley to slow it down and then to the 4 1/4 in drive wheel. The belt feels like it is running at about the right speed so it will grind nicely.

[Von Gruff]

Another little part of the project came together today with the plunge line jig done although it still needs hardened yet.
The end of a file I had made a knife from with some die and a couple of scribe lines marked in
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0152_zpssthbpcb9.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0152_zpssthbpcb9.jpg.html)
A bit of cutting and I have the required parts.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0153_zps4i363z2v.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0153_zps4i363z2v.jpg.html)
A while later with a bit of shortening and a pair of holes so I could grind it all paralell and it bolts onto the knife to define the plunge line. It will ensure that both sides are exactly the same.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0154_zpsnstukesn.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0154_zpsnstukesn.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0155_zpscvw6iogw.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0155_zpscvw6iogw.jpg.html)
This is only part of the jig as there is a piece of angle alluminium with a hinged base plate that this little plunge line jig fits into and clamps onto so the bevel grinds are both exactly the same as well.

[Von Gruff]

The second part of the grinding jig was completed today. A foot length of 3x3x1/4 in alluminium and a piece of flat 3x1/4 in along with a length of piano hinge and a couple of bolts. I used aluminium for its lightness and that it will act as a heat sink but can all be dunked in the water bath to keep things cool without the worry of rust.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0161_zpsox9nyaaq.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0161_zpsox9nyaaq.jpg.html)
With the flat piece hinged to the angle I cut three areas to take the jig. For short knives I can work out from the end cutout
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0162_zpsyzujc7tp.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0162_zpsyzujc7tp.jpg.html)
You can see from this shot that the bolts screw the angle up from the base at the rear to give the required angle for the bevel grind. The bolts make a handle to hold and guid the jig with.
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0163_zpszf37dbok.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0163_zpszf37dbok.jpg.html)
This is an already ground blank in the jig with the square showing where the belt would run
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0165_zpsr52dtewt.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0165_zpsr52dtewt.jpg.html)
Knives with mid length blades can be done from the center position
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0166_zpsewon7m8e.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0166_zpsewon7m8e.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0167_zpsfd32rjj6.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0167_zpsfd32rjj6.jpg.html)
And long blades can be done from each end but facing inward rather than outward for the short blades
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0168_zpsp7dz65w0.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0168_zpsp7dz65w0.jpg.html)
http://i1070.photobucket.com/albums/u488/vongruff1/knives/Grinder/Knife%20holder/DSCN0169_zpsrwie1pup.jpg (http://s1070.photobucket.com/user/vongruff1/media/knives/Grinder/Knife%20holder/DSCN0169_zpsrwie1pup.jpg.html)

[Kalahe]

All the knifemaker's that I know will have at least one 2x72, most have several. 2" x 72" belts is the normal....easy to find, ecomomical, many different types. When you get into the other size belts you get more into hobby machines, you will not have so many different types of belts to choose from. Although you can buy 1" wheels for most grinders. The KM2 especially.
You can always split a 2" belt if you need a narrower belt. Take a knife point and pierce the belt, just a small cut, and then pull it apart. The small cut will follow all the way around the belt. You can have any width you wish. A 1/4" belt will run on a 2" wide wheel. To slack belt, on contoured handles and guards.
I agree with dave.....if funds permit, go with a Variable.....If you don't have the funds, sell one of your rifles.....you can always buy another rifle with the quality work you will be doing using the variable speed.
When you consider a grinder, ask yourself the question "What are you going to use it to do. Grinders come in front drive, and rear drive.
The KM2 that Dave reccomends has a rear drive. I have one and love it, wheels are easy to change.....but if you want to use your grinder to buff then you need a front drive. I have a Burrking, that can double as a buffer.
Another very good versatile grinder is a Wilton Square Wheel. Very similiar to the Bader KM2..... I have one that is an Olympic.....Wilton bought out Olympic https://mechanicguides.com/best-belt-grinders/ and called it a Square Wheel....mine is Really really OLD, and is stiIl running good.
I started out with home made grinders, and have owned all the major brands. If I could only have one grinder, it would probably be the Bader KM2 WITH VARIBLE SPEED. IMHO.....DON'T BUY
However, for fine finish work, you can't beat the Burrking. It runs very
smooth.
BTW, If you buy the KM2, you can build most of the extra accessories yourself. You will never own just one grinder. They are like .22 rifles, or Sumphen like that.
One other thing, of the thousands of things everyone here could tell you ...
Here's a couple things to think about.....If your going to hollow grind, and take the grind to the spine, save yourself some money and head aches and go with a 12" wheel. Semi-soft (durometer) wheel.... Hard serrated wheels are for profiling, rough removal.....the softer the wheel, the smoother the cut, use a soft wheel for final finish.
If your going to flat grind, then a 8" hard serrated wheel will be fine for profiling and rough grinding. Hope this helps
On YouTube there are a lot of interesting videos...

https://www.youtube.com/watch?v=Q4zslHF5L2M

[rking22]

Timely resurrection, Im in the process of buildinv one right now. Using a treadmill motor with "dimmer" and bridge diode for variable speed. Phyzical design very like Von Gruff's project. My drive wheel is turned from alum and bored for the motor flywheel. 3.82 dia lets the tach i got from china display ft/min of belt speed. Got all the parts just gotta put it together.

[woodbutcher]

:-D Hi Von Gruff.Very informative and interesting thread.Thanks for posting.
Good luck.Have fun.Be safe.
Leo

[Guntzy]

Great info. Thanks for sharing