Finish sanding lengthwise on a wheel

Varga Knives

Varga Knives

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Aug 12, 2006
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I tried this the other day but hesitated to post my questions until I saw Nathan's thread and figured maybe I'm not that far out. I have a KMG but most of my shop time is spent hand sanding because every time I try finishing on the grinder I always find a way to gouge out a chunk of steel. So, I tried 220 grits and up on an 8" wheel running the blade lengthwise and loved the results. Just kept quickly moving the blade back and forth on the top curve and I could do no wrong. The only problem is of course the area near the plunge. I obviously can't grind too close for fear of hitting the ricasso.

Does anybody else finish off their knives this way and have you found a way to hit the plunge aside from the flat platen? Okay, maybe Nathan has the only answer but he won't sell. Yet...
 
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Since nobody is chiming in with a better idea I'll just throw this one out there... Inspired by Nathan.

How about removing the bottom wheel on my flat platen (bottom is closer to a right angle to the drive wheel) and putting a radius on the bottom of the platen. Maybe then cover the whole platen with a piece of leather to be more forgiving or use the cork belt under a flexible belt idea from another post? Of course the whole thing would have to be run at slow speed but that's ok. Stupid? Anyone?
 
Are you sanding a flat grind? If so, yes, you can cut a radius on a flat platen and sand lengthwise. Not to spam my flat platen, but that is the purpose of the radius machined onto the end of them - lengthwise sanding and plunge grinding. Plenty of people do this.

I leave the bottom roller on and remove the top roller, then angle the platen back so the belt isn't being drug around more of the radius than you need (you don't need a right angle). I think some people do it the other way, though I worry about the tip biting in.

Grinding this way means a launch will send a blade flying point first. It is common sense, but I'll point out the obvious - you shouldn't grind like this with your balls in the potential flight path, you should stand to one side or the other.

You will find that grinding with the belt wrapped around the platen instead of a roller generates a lot of heat. It is enough to burn a belt if you're not careful about it.
 
Thanks Nathan! Tip bite sounds like more of an issue so I think I will try it from the top. Oh, yes it is for flat grinding.

I think the cork underbelt would serve nicely but how would that react when no rollers are used? I know it would have to be slow going and since I have variable speed that won't be the issue. Maybe felt on the platen?

Thanks.
 
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I've done it lengthwise on a wheel, but just to help speed up the hand sanding. Never got the finish I wanted right off the wheel.

I've also seen grinders set up to grind lengthwise with a radius, or small wheel at top. Someone was selling one at some point years ago, but can't remember who.
 
Nathan the Machinist said:
Are you sanding a flat grind? If so, yes, you can cut a radius on a flat platen and sand lengthwise.

I leave the bottom roller on and remove the top roller, then angle the platen back so the belt isn't being drug around more of the radius than you need (you don't need a right angle). I think some people do it the other way, though I worry about the tip biting in.

Grinding this way means a launch will send a blade flying point first. It is common sense, but I'll point out the obvious - you shouldn't grind like this with your balls in the potential flight path, you should stand to one side or the other.
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Good safety tip right their. Excellent mental visual effect
 
Ah ha! Looks to be a Beaumont small wheel attachment. Assuming the 1/2" rubber wheel makes for a good plunge, there are only a couple of things that I have concerns about. As it is being used in the link, the surface area of the platen was not intended by Beaumont to be used like that so is that an issue? Could that platen still be covered in felt or leather or something to be more forgiving?

Is the gap between the surface area of the platen and the small wheel going to be a problem in that there would be no pressure from underneath for the first couple of inches after the plunge?

The last thing it would need to run on a KMG in this manner would be an adjustable angle. Like a pivot that could be locked down when it is parallel to the belt.

I know I threw out too many questions but I'm really looking to do something in this direction.

Thanks.
 
strider214 said:
Ah ha! Looks to be a Beaumont small wheel attachment. Assuming the 1/2" rubber wheel makes for a good plunge, there are only a couple of things that I have concerns about. As it is being used in the link, the surface area of the platen was not intended by Beaumont to be used like that so is that an issue? Could that platen still be covered in felt or leather or something to be more forgiving?

Is the gap between the surface area of the platen and the small wheel going to be a problem in that there would be no pressure from underneath for the first couple of inches after the plunge?

The last thing it would need to run on a KMG in this manner would be an adjustable angle. Like a pivot that could be locked down when it is parallel to the belt.

I know I threw out too many questions but I'm really looking to do something in this direction.

Thanks.
Click to expand...
Not a Beaumont attachment, all made by Uncle Al. I see no reason felt or leather couldn't be used on the platen, or a smaller wheel for the radius. Pull the blade lightly off the small wheel each pass to make up for the gap. It wouldn't be too hard to make something similar to fit a KMG. When I saw it demoed on integral blades, it worked mighty slick. This was about 10 years ago, so it's been around for awhile.
 
Really great discussion here! I'm looking forward to trying out some of these ideas/tips.:thumbup:
 
jonnymac44 said:
Really great discussion here! I'm looking forward to trying out some of these ideas/tips.:thumbup:
Click to expand...

I agree. I've seen Brian Fellhoelter grind in a similar manner using his water-cooled platen. I believe there is a video on YouTube showing it .
 
I think a neat idea too would be to attach a small square block above the bearings on either side of the wheel with their faces flush with each other. Then you could attach a file guide to the blade and have the blocks (or bars) act as a fence. Not sure if it would work right without a lot of tinkering, though.

Edit: dumb idea and won't work. At least I'm trying. :)
 
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Charles Ochs holds his knives in a vertical position and grinds his knives using a 3" wheel. His plunge line is what the 3" wheel makes. He gets a smooth finish by quickly moving the blade in a up and down motion.
I have made some knives this way, (My Jouneyman ABS knife), but it's not my favorite method.
 
If you are doing flat grinds, you might look into a vari speed disc grinder. The ability to grind at slow speeds up to say an 800 grit sure does put me ahead when its time to hand sand. Just a thought. Ive seen Uncle Als integral grinder, and while I havnt tried it, Im thinking one could be made off of a kmg small wheel attatchment if a platen were made to support the belt behind the wheel.

Good Luck!

God Bless
Mike
 
You are talking about what Nathan kindly stated he already makes, and something Brian Felhoelter made for himself and uses,Kyle Royer uses one in his Journey videos too. I know a couple others that use a radius platen.

Look in the for sale area at the flat platens and if they are still there the water cooled platen chillers.

Here's the best thread on the subject.
http://www.bladeforums.com/forums/s...nt?highlight=Radius+platen+water+cooled+Brian
 
Another tip for the plunges is to use the wheel to finish out the majority of the knife and use edm stones for the plunges. They last way longer than sandpaper and contour to the shape of the plunge to a degree.
 
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