Belt Sander Grinder Jig *LINK*

Honing Plate

Derek Cohen (in Perth, Australia)

>This is a picture of the honing plate. Used with Veritas green rouge, blades are hand held and the direction of spin is behind the bevel.

To avoid any dubbing of the blade, the "plate" is hard and flat - two disks epoxied together, with the velcro on the outside.

The blade is rocked forward until flat on the surface.

The whole process takes about 2 seconds for an amazing quantum leap in sharpness.

Regards from Perth

Derek

Bevel angle setting jig

Derek Cohen (in Perth, Australia)

>This is my latest jig to set the bevel angle. It is just a variation on and incorporation of the many similar ones that I and others have posted here before. This one is just more accurate and allows me to make tiny adjustments.

Built from jarrah and a wide steel rule. Polyester on the depth gauge to prevent damage to the blade edge.

As you hopefully can tell (in this dark picture) the depth gauge is adjustable (moves back-and-forth).

Regards from Perth

Derek

Nicely done!

David Barnett

>Nice system you've put together, Derek, and thanks for the post w/pics and thread. Although I'm somewhat set in my ways by now with both vertical and horizontal rotary grinders, this certainly is a viable alternative with some advantages, as you've pointed out. I've been considering getting a variable speed Wilton "Square Wheel" grinder, and although it will do both flat and various radii hollow grinds, I'd never really considered it a sharpening tool -- more of a versatile shaping and finishing system. Anything else I can use it for makes it even more attractive. It's a two inch belt, though, but that shouldn't be a problem. I'll just have to make a jig that'll work with a vertical platten. Do you know the SPM for your belt sander?

I meant SFPM, of course.

David Barnett

>

What is SFPM ?

Derek Cohen (in Perth, Australia)

>

Can you post this in Articles & reviews?

Ian in Sydney

>Greta info Derek

Can you reformat and post it this in WC's Articles?

My guess is surface feet per minute, Derek

Andrew F in Australia

>Nice work, by the way.

Andrew

Article?

Jack Guzman from Maine

>That is a very practical post Derek.Thanks for sharing it.I bet it would be handy to have that available in WCs articles section.I'm making myself a copy of it.I've been debating getting rid of my sander,I never use it.---Jack

Re: Can you post this in Articles & reviews?

Jack Guzman from Maine

>I have to reset the clock on my computer.We posted at the same time.Actually you posted while I was still typing.---Jack

Re: Can you post this in Articles & reviews? *LINK*

Derek Cohen (in Perth, Australia)

>Hi Ian

Ironically, I had prepared an article on this jig already, not for WC but for Fine Woodworking magazine (at their request). This was submitted about 10 weeks ago (and more) but I have had no word from them (with the exception of an email reply about 6 weeks ago when they said they would get to it in a couple of weeks). Clearly they are not interested. Their loss is WC's gain!

The reply (link below) just made me determined to post this now to circulate the jig amongst those interested and for whom it may prove helpful.

Regards from Perth

Derek


http://www.woodcentral.com/cgi-bin/handtools.pl?noframes;read=64509

Re: Nicely done!

Bob Fawcett

>The Wilton Square Wheel is what many knifemakers use. As you said it is great for basic shaping and grinding, but with fine grit belts, it is used for sharpening as well.

2 x 72 belts are available with grits as fine 600 dry and 800 wet. There are special cork belts designed to work wet that can be had in 800 grit.

I have a homemade 2 x 72 belt sander (talk about ugly). I made it from sccrap steel, industrial metal wheels with solid rubber tires, and skate board wheels.

One source for belts is Jantz suppply. They are a knifemaking supply house.

www.knifemaking.com

Re: Nicely done!

John in Kansas

>Derek,

Thanks for posting all the sharpening information. I already have a 4x36 sander so am definitely going to make one of these setups.

One question: Do you know of any place online a person can purchase the 1300 grit belts? I have inquired with most online locations and the best they can do is 800 grit.

Thanks again!

John

Re: Nicely done!

Derek Cohen (in Perth, Australia)

>Hi John

I don't know who to contact on-line, but I am sure that someone will be able to supply them if they know what to look for since the belts are not marketed as 1300 grit, per se (but that is what they are rated at).

These belts are made by 3M and the identifiers are "Trizact", "237AA" and "A16".

These belts actually shimmer with shiny threads. They leave the bevel with a mirror-like shine.

Hope this helps.

Regards from Perth

Derek

Trizact also comes in 6-micron...

David Barnett

>...which is FEPA P-grade equivalent 2500. I think you'll need to call 3M abrasives division to point you toward a 4"x36" 16-micron belt, if such a thing exists. Trizact is great stuff, although I've never used any wider than 1/2".

Re: Belt Sander Grinder Jig

Steve Knight

>you did a good job. the jet comes with a tool rest so you just need soemthing to help hold the tool square I made something after this picture.

alos to keep from wearing out the bed of the sander I used a bar of hard 0-1

Re: Belt Sander Grinder Jig

Derek Cohen (in Perth, Australia)

>Thanks for posting pics of your belt sander Steve. I had looked all over for a copy, recalling that you had done something along these lines, but could not find one.

This sander was actually inspired by the memory of yours, along with seeing Tage Frid sharpen his chisels on a 220 grit belt sander (free hand!) then hone on a leather wheel, and then procede to cut all his dovetails. I thought I might improve on that.

I found that the steel bed of the 4" belt sander (Mk I) warped eventually, which I put down to heat generated in one area. This was fixed by adding a flat steel plate (I used the rear of a worn out diamond plate). Others who have constructed the jig using similar steel bed belt sanders have experienced the same effect, and their repair was to use a piece of float glass glued to the bed. This has also worked perfectly well. My recommendation to those using a steel bed sander is to do this up front.

The reason I upgraded my belt sander to a 6" wide machine was primarily for the extra heft and the cast iron bed. I had planned to add a steel plate to this anyway (in the form of a recycled Tyzak saw blade), but so far it does not seem to need it. Do you think I should add it anyway as precaution?

Regards from Perth

Derek

Re: Belt Sander Grinder Jig

Bob Hackett

>They make graphite plattens for belt sanders,this might be a better approach to the problem.

MB

Very nice...

Scott Burr in Ben Lomond CA

>Excellent job Derek. This is very insteresting to me. Is that sander available in the states? Does anybody know of one like that that is?

Again nice job.

Re: Belt Sander Grinder Jig

Derek Cohen (in Perth, Australia)

>MB

No, a graphite slip is not a good idea in this situation. I have been down that road already. The problem is that the slip compresses as pressure is brought to bear over such a small area. This transfers to the blade, which is then ground to a similar shape (i.e. a curve). A hard, flat surface is needed.

Regards from Perth

Derek

Re: My guess is surface feet per minute, Derek

Derek Cohen (in Perth, Australia)

>Hi David

I cannot say with absolute certainty what is the speed of the two machines I have used (the 4" MK 1 and my current 6" MK 2). However the figure of 1400 rpm rings bells. This is quite a bit slower than a standard grinder (3500 rpm) and slower still than a half-speed machine (1750 rpm), but much faster than a Tormek (70 rpm). So there is a good compromise between reduced heat and real grinding speed.

Regards from Perth

Derek

Re: Belt Sander Grinder Jig

Steve Knight

>glass is a good idea. though it would be a pain to hold down and remove. but protect that surface belts are pretty abrasive things.

Re: Belt Sander Grinder Jig

Steve Knight

>thats whats under my belt (not pictured) and they would get a groove in them in a few sharpenings. but they are a must under a belt when not sharpening.

Re: Belt Sander Grinder Jig

Don Thompson - Cutler Ridge, Florida

>Steve,

Why doesn't the stiffness of the belt, and the shortness of the O-1 platten cause the belt to arc over it?

BTW, how many times do we have to tell you to take off the jewelry and watches when using your power tools!

FWW may still use your article

Ian in Sydney

>Not so much a defence of FWW but a possible explanation.

A bi-monthly magazine like FWW will have a two month production cycle for each stage of the process. The June issue has just been delivered so it's probable that artwork for the August issue is being finalised now, articles for the October issue edited and those to be included in the December issue selected. Topics to be covered in the first two issue s in 2006 have probably already been selected. Miss the cut-off date for inclusion in one issue and it would be two months or more before the editors get back to your article.

Also if FWW are planning a feature on stationary belt sanders they might hold your jig till then.

So, thanks again for publishing it here.