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Radius Grinder Platen, MAIN SALE

Nathan the Machinist

KnifeMaker / Machinist / Evil Genius
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Knifemaker / Craftsman / Service Provider
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Sold Out, thank you.


36", 48", 72"

These are precision machined of A2 steel and hardened to HRC 61-64. It is 1/16" shy of 8" to fit between the rollers, 2" wide and has the KMG 1/4-20 6.75" center to center mounting pattern. $100 shipped continental US.

This is the main platen sale for 2012. I haven't done one of these in a while. I appreciate everyone's patience.

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There are five 36" platens, ten 48" platens and three 72" platens. Let me point out that the 72" is too subtle to see with your eyes. It is really only useful for folks making certain kinds of kitchen knives.

In using these platens I have found the effect is subtle, but noticeable. It isn't a flat grind, and it isn't a hollow grind. I believe this is a historically accurate grind for blades ground in yesteryear on really big stones. I see this being a cool grind for blades made in an older style, and blades like kitchen knives that you would want a full height grind on a tall thin blade.

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This lot of radius platens is different than previous runs. If you look closely, you'll see a tiny hole in the surface of the platen. On the opposite side of the hole I have cut a 1/4" NPT pipe thread (a regular taper pipe thread) which you can (if you want) use to pressurize your platen with air.

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I wish that I would have thought of this myself, but this is a feature that I have added by request. However I have tried it and it does work. One of the problems of grinding on a radius platen is heat, and the addition of air between the belt and the platen both reduces friction and cools both of them. It is possible to grind with high belt tension and a large contact area at your highest speed for hours at a time without excessive heat buildup. This only works well with a stiff belt. Once you get into something like a j flex you will find the air cushion rounds the leading and trailing edge a bit. At this point you will want to move away from the air zone or reduce air pressure. I get best results with the air pressure between 5 and 50 PSI.

You don't have to use air to use these platens. This is a feature I have added for folks who do extended grinding and have problems with excessive heat build up.

If this platen will fit your grinder and you would like to buy one of these, I need you to please follow these instructions to help me keep up with everything (otherwise folks will fall through the cracks).

1: State your claim in this thread.

2: send me an email (not a private message) njcarothers at windstream dought net

The email should include what size you are buying, your BladeForums handle (i.e.: "Nathan the Machinist"), your actual name, your shipping address and your paypal email address.

I will send a PayPal invoice to that email.

3. Pay the paypal invoice. Once it is paid, I will ship your order to the name and address you gave in your order email.

If you don't want to use paypal, we can arrange to send a check.

I hope there are no shortages, but if there are, it will be based upon first come first serve who posts in this thread. I have to do it this way to keep things sane.

Thanks,
Nathan
 
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Nathan I will take a 48" .... thank you. Sending Email
 
I will take a 48" -- thanks Nathan!

Information sent as per your request.
 
Sorry Metzger, they're taken.




It appears I may have underestimated the number of platens I needed to make. I figured I'd end up with a few extra living on my shelf for a while. I'm sorry about the shortage.

I will get more material on order and plan on fitting in some more the next time the machine opens up. Figure on another sale this summer.

I will start invoicing tonight with the aim of shipping these at the end of the week.

Thanks everyone for another good sale.
 
Please do Nathan, I was expecting these a few weeks later, and would have liked one of each. I can wait a bit, but not another year. ;)
 
I might add a 36" and or a 72" to the 48" I ordered when you do your next run. I'm glad your sale went well!
 
I am so glad I had my phone on me when this came out. I would have missed it again if i had to wait till I got home. THough I hate the leash sometimes I am very thankful for technology too. :D
 
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