Making the Plunge

J

Jim Harvey

Joined
May 5, 2000
Messages
31
Ok, you start with a blank that's been roughed to shape. You do your file work or your grinding to bring the blade shape closer to finished. Fine and good, Now when you make that plunge by the ricasso, tell me how you keep things even. Is it a fixture ?( 'cause my freehand leaves a lot to be desired!) One side will be "almost right" while the other side looks as if I've consumed that 18 pack of the really cheap beer.
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My wish list? how about a blade symposium here on the EAST COAST! ( New York Area preferred!). There's got to be something that I'm missing!
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[This message has been edited by Jim Harvey (edited 07-09-2000).]
 
It takes a lot of practice and patience to learn to grind the plunge evenly. There are jigs available but they are quite expensive. After a few blades you get a feel for the plunge and it goes better. If you like a rounded plunge you can round the edges of your platen or wheel , this also makes it easier.

Marcel
 
Well, with files, it is very difficult. Maybe try a square file and work at the plunge to cut it so it is deep. Put something on the blade so you don't go past it. It is much easier on a belt sander. Trust me, I went from hand filing to sanding and have some good success with it!
 
What I found works best for me is to put a mark with a fine line felt tip marker accross the blade a little forward of where you want the plunge cut to be.As you start your grind start ahead of that mark and lightly lay the blade up against the belt and move back to that line with medium pressure.Then grind forward in one long sweep. Now if you have the same belt overhang on each side of the platten and you have broken down both sides of the belt with a piece of hard steel, hold the blade level as you do each side,everything might come out right.
 
I found somthing that is cheap and easy
just leave your knife rest on and take a peace of bar stock about 3/16 inch thick
and C clamp it to your rest put the edge of the blade up
and put the rib of the knife against
the stock start were you want your plunge push your blad in and make a pass do the same on the other side as the stock is removed just move the bar stock in and
you can hollow as hi or as low a line as you want.It works great sound to easy but give it a try just make sure you keep the rib of the blade pressed against the bar stock
that will keep your line straight.
cost me about 15 cents verses 300 for a hollow grinding jig.mark a line like posted earlier in a post and just grind about na 1/8 inch in front of that and you should be in good shape.
 
I just file a small notch where my choil will be and use that as my reference. Also scribing a light line where the edge of my guard or bolsters will be helps me keep the front of the ricasso from leaning in a direction that I didn't want to go.
 
practice, practice, practice. I start at the edge and work up....and leave the grind start until the end.....I grind mostly on a ten inch wheel but do the same thing on flat grinds when i do them....the main reason is that I use very stiff ceramic belts for the initial grind, and they do a very poor job of making a nice curve at the grind start.. or plunge as some of you call it....i get it down to about the thickness I want at the edge and dont worry about the place where the ricasso and the grind meet until i switch to a flexible 100 grit belt on step number two..which is to get out the 50 grit scratches and clean up the grind start area at the same time...I still dont worry about getting it perfect here....that comes when i go to the 220 grit belt, and the 320, and the 400/// thats how i do it.....it certainly takes a lot of practice...because you can end up with NO ricasso pretty quick if you arent careful....one key is the roll you have under the belt...I have tried to make both sides of my wheel exactly the same, a slight radius at the edge with a little roll for about half and inch...keeps me from getting a bad two inch line if im not being careful and I end up with nice even grind starts....the bottom is the place i watch the most....and the top where the grind ends..the rest takes care of itself if you keep it even and have true scribe lines on your blade...I only scribe the edges on hunters...but on double ground fighters i scribe a line to grind to along the flat.. just for the bottom or the top..what ever i am doing first....if you grind the top first you get a very straight line down your blade, the bottom first you get a nice curve.

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http://www.mayoknives.com


 
Any one have any pictures that they could lend to the suggested procedures.

Pictures showing how to scribe out the line or use the C-Clamp to set up a guide..

Every little bit of info helps..

Thanks Guys

Jim




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The warrior will endure great personal hardship in order to stand on a hill, howl at the moon, and proclaim his domain over all he surveys. Fredrick Lovert- Author
 
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