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help with a knife sharpening wheel..

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MD11

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Looking for a 7" x 1 x 1 wheel to sharpen knives and possibly axes (final sharpening)..

I'm finding a few options..

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260746070237#ht_1460wt_1180

http://www.grainger.com/Grainger/NORTON-Straight-Grinding-Wheel-6A089?Pid=search

http://www.grainger.com/Grainger/NORTON-Straight-Grinding-Wheel-5A891?Pid=search

Sadly, I don't think any of it is US Made..

Anyway,anyone with experience in this area have some good suggestions for me? or are the above sufficient?

thanks

I've got a Baldor 762 / 3600rpm with 5/8" arbor.
 
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Outlawmws

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MD11, Slow down, literally! :lol:

3600 RPM is WAY fast for a knife sharpening rig. You want slow to prevent burning up the blade. Heat management is the issue, and at 3600 RPM the SFPM of that 7" stone is HUGE.

What you want is a 1725 rpm grinder at the highest, or better still, one of the larger belt driven Wet reservoir units with a jack shaft to really slow it down (Under 100 RPM?). The water keeps it cooler yet, and is a better system.

A high speed grinder might be used for roughing out blades as some one makes it from a blank, but even there I think most knife makers prefer a belt grinder.
 
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MD11

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Thanks outlawmws.. I knew it was too fast for an ideal grind, but sadly I don't have a speed control. I was looking for just an edge sharpening and no real pressure/grinding..

The other option is I can just tell my wife... No. It was her suggestion to put it to additional use as a sharpener.
 
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woody 73

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MD11 my idea is way out of your price range but if you can locate a used Tormek machine ; It is not made in the USA but the machine is well made, it has a very wide wheel that will move very slow in a tray of water.

Woody:)
 
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MD11

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thanks Woody, yeah, if I wanted to go that route, I'd do that.... but this was a side venture for the grinder, not the purpose for it's purchase.

I think I'll just play with it on a 120g wheel and see if I can put an edge on some of the old cheap knives we have laying around.
 
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Tnsejed420

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Its way too fast. Outlawms is correct.

The main issue you have is that you are dealing with a temperature barrier which is that of the tempering temperature the maker used to temper the blade.
You won't really have to worry about the bevel section of the blade itself. You have to worry about the edge. Micron thick sections of steel that will heat up so fast you will never notice it.

When I do my edges my grinder is running at approximately 50rpm and I'm using a 9" disc. Abrasive surface feet per minute is key here, not RPM.

Are you actually trying to put an edge on a freshly ground blade or are you trying to maintain an edge?
 
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MD11

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Tnsejed420 said:
Are you actually trying to put an edge on a freshly ground blade or are you trying to maintain an edge?
Click to expand...

no, just maintain the edge on some old kitchen knives. Doesn't the amount of pressure I apply also effect heat? what if I go very light touch?
 
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Tnsejed420

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Yes, the amount of pressure will affect it but at speeds like that bench grinder it won't matter.

The actual edge. The section that reduces itself to infinity until the carbides fall out of their lattice structure is the area that needs to be the hardest. Heat will build up in split seconds.

For maintenance you will get the best results using stones. For edges that are very bad use a course diamond stone first then work your way up the ceramic grits.

I recommend DMT stones to my customers for a bench type stone and I recommend a Sharpmaker system for those not proficient with a bench stone.

I know it *****, and there is a learning process to working with stones, but it is the best way to get a good edge and maintain it.

A little spinoff here. Edge maintenance is important. A couple swipes every now and then is better than letting the knife go completely dull and having to spend a long time rebuilding the edge.
 
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woody 73

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Tnsejed420 said:
Yes, the amount of pressure will affect it but at speeds like that bench grinder it won't matter.

The actual edge. The section that reduces itself to infinity until the carbides fall out of their lattice structure is the area that needs to be the hardest. Heat will build up in split seconds.

For maintenance you will get the best results using stones. For edges that are very bad use a course diamond stone first then work your way up the ceramic grits.

I recommend DMT stones to my customers for a bench type stone and I recommend a Sharpmaker system for those not proficient with a bench stone.

I know it *****, and there is a learning process to working with stones, but it is the best way to get a good edge and maintain it.

A little spinoff here. Edge maintenance is important. A couple swipes every now and then is better than letting the knife go completely dull and having to spend a long time rebuilding the edge.
Click to expand...



Woodcraft also sells the DMT Stones.:beer:
 
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MD11

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Tnsejed420 said:
For maintenance you will get the best results using stones. For edges that are very bad use a course diamond stone first then work your way up the ceramic grits.

I recommend DMT stones to my customers for a bench type stone and I recommend a Sharpmaker system for those not proficient with a bench stone.
.
Click to expand...

I have one of these, will that suffice? I've used it for keeping straight razors sharp, but I always imagined it was too fine for kitchen knives.

http://www.bestsharpeningstones.com/catalog/Belgian_Coticule.htm
 
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MD11

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trboxman said:
It's hard to have kitchen knives that are too sharp...
Click to expand...


well good point, but I'm contrasting to a straight razor which are stupid sharp... if you know what I mean since they're not made of stainless steel.
 
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Givl Reggin

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In woodworking circles there is a method know as "Scary Sharp" that uses a flat surface (piece of plate glass) and various grits of wet-dry sandpaper. I've been using this method now for over 15 years to get a keen edge on everything from wood chisels to lawn mower blades to kitchen knives.

Full details of this method are described in this usenet posting here...
http://groups-beta.google.com/group/rec.woodworking/msg/798769fbc0a3e6a3?dmode=source
 
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