hand satin finish- need help

Jack O'Neill

Knifemaker / Craftsman / Service Provider
Joined
Nov 15, 2007
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6,792
I like a hand satin finish on my flat ground blades but keep running into this same problem . some little swirls in the finish when looking at the blade from a different angle in the light. I use a flat piece of steel or wood for backing for the paper . I start at the ricasso grind and push forward to the tip paying attention to keeping a straight stroke . Oops seem easy to create and hard to repair .this is driving me nuts . HELP . Also, any opinions on fine glass bead finishes .
Thanks for any help you all can give me
Jack
 
Joined
Sep 23, 2006
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366
Not that I'm any sort of expert or anything, but I do have an idea...

you could try polishing to two or three grit levels finer than the final satin finish grit level you want, making the finest of those as even and straight as you possibly can, then back up to the satin grit you most like and make your full length strokes as even as possible.

This should let you see very very clearly any swirling or off straight polishing you may be making as you go.

Also, you could rig up a guide of some sort to press one end of your sanding block up to, so you always have a straight and even stroke.
 
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Jul 6, 2005
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To get a straight even finish I don't go back and forth and just "push" the paper down the blade which prevents the "fish hooking"
 
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Nov 18, 2007
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I wrap my sand paper around a piece of micarta. It is approx 3/16" x 1" x 3". I start at the plunge cut and pull straight back to the tip. Then lift the paper and go back to the plunge cut and do it again as many times as it takes to get what I want. The fish hooks are caused by stopping and changing directions with the paper. It doesn't take much change to form them. I too go 2 grits past what I want for a final finish, then go back to the grit I want and try to make only 1 or 2 passes to finish everything out even.


Lots of practice and patience helps too!!!!
 
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Oct 30, 2005
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J.Neilson has a tutorial on satin finishing where he wraps the sandaper around a (I believe leather covered block) which he puts in a vice then lays the blade on it and pulls the knife to the point with pressure on the block . As Steve said above pull in one direction only to do it right. Mike
 
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Dec 27, 2007
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Lots of practice and patience helps too!!!!

+1.
Also experiment with different blocks( meaning hardness, shapes, etc.)
I use a wedge shape plexiglass block for heavy work as the sharp edge concentrates the effort. On the finer finish I go to wood blocks and end with a 1 " square block that is about 12" long, this way I have a nice comfortable handle on either side to work with. On one side I glued a piece of leather to sort of cushion things. I also rounded the edges of the leather. It gives a better finish imo. When I get to the leather block stage I also use oil instead of water. I finish with another leather on wood block with no paper, just impregnate the leather with red iron oxide. It's almost a hand rubbed mirror finish.
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Joined
Dec 24, 2005
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This might help. First off, good lighting is very important and will save you work in the long run. Second, hold your blade in your vice with the point facing you and angle the point down (15 to 20 degrees) Wrap your paper around some thing as the other guys have said, use some WD40 or similar light oil and pull towards you from the ricaso to the tip.

Angling the blade down helps minimise the tendancy to pause because you are sliding down hill. I have explained this to a lot of guys down here and they all say it has improved their finish heaps.

Tear the paper off as it wears to reveal a fresh piece. The cusioning effect of the layers or paper act the same as a piece of leather. On big Bowie size blades I also recommend backing the paper with leather.

Obviously don't get distracted or leave the blade unattended when you are working with the blade in this manner:eek:. You may prefer to fix the blade to a suitable sized piece of timber and hold the timber in the vice. This has the added advantage of supporting the length of the blade as you work on it.


Peter
 
Joined
Dec 8, 2005
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707
I reckon one can clamp a longer piece of hardwood (something like 1x2x whatever long) to a workbench to act as a guide of sorts. Then you clamp your blade parallel to it. Using a block with paper around it, slide the block along the said guide , while touching it of course. This way it will all be straight and you just might be able to use both forward and return motion w/o causing swirlies.
 
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Aug 1, 2008
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one of the most important things IMHO is to have a somewhat soft backing for the finishing strokes. A piece of leather or soft neoprene rubber works the best. You already have the blade flat from grinding/sanding so there is no worry about causing any unevenness with the last grit of paper that you are going to use.
 
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Mar 4, 2006
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I work up to 1000-1200 grit, then apply the satin finish with 600 or 800 grit. Like many other, I back the sand paper with a piece of wood, plastic or leather (leather is my favorite for small blades). I always draw the sand paper towards me in one continous motion. Use strokes the entire length of the blade. This seems to give me better results than pushing. I only take about 5-6 strokes on the sand paper then move to a fresh section, no water or lubricant.

Ric
 

Jack O'Neill

Knifemaker / Craftsman / Service Provider
Joined
Nov 15, 2007
Messages
6,792
you have all been great , thank you very much for taking the time to help me out . That is one reason why I like this hobby so much , everyones willingness to help and share knowledge.
Keith- thanks for the video link , it was good
Shike- those pics were beautiful.
Jack ONeill
 
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