Swivel Knife blades

[hidepounder]

Allen,

Initially I thought you were talking about something other than the normal drag which occurs when cutting with a steel blade, but it sounds like that is what you are experiencing. I have never used ceramic so I am accustomed to stopping to strop. You may already know this but maybe someone else here doesn't. One of the things you can do to help eliminate the drag when cutting, is to add soap when you case your leather. I had heard of this for years but didn't try it, now it is part of what I do when I case all my leather. I add several drops of JOY liquid soad to my pan of water when casing, and then I take a piece of wet woolskin scrap, and apply a light coat of IVORY bar soap lather to the surface of the leather. The next day when I start cutting, most all of the drag is eliminated. I don't know if the soap is simply lubricating my blade or if it is nuetralizing the acids in the leather that cause the chemical reaction resulting in drag...I was going to research this and decided I really didn't care! It works and I'm happy. The addition of the soap when casing has never effected the finish on my leather, by the way. I use Herman Oak leather and most of the sides are pretty good, however occasionally I'll get one I almost can't cut, but the soap solves the problem!

Bob

Edited January 9, 2009 by hidepounder

[steveh]

Allen,

You said that you getting drag on tight corners. When I cut with a swivel knife the pressure on the blade is always changing , as I begin a cut it is deep and wide, and fades out in depth and width as cut terminates. When I cut scallops and tight corners , I spin the barrel of the knife and almost pause the motion of the blade at tightest point to where there is little to no pressure on the blade, this method reduces drag for me. I like width with on the bevel of the blade, as this opens up leather. You may want to practice this and see if it works for you.

Steve

[Big Papa Leather]

Steve

I do have to work a bit on the control of the depth of my cuts. I tend to want to make everything as deep as I can go without cutting through. I noticed on a scrap piece last night that if I "lay-up" a little in the turns I can reduce some drag, but the beveling suffers a little as it isn't as deep and defined.

I will play around some more.

I am tempted to re-grind one of the Tandy blades to match the angle of the ceramic blade. The bevel is same angle but the the angle of the taper is different on the Tandy and the Barry King blades (steel).Even the Tandy steel filigree blade is slightly more obtuse. If I re-grind the blade (for a lack of the correct terminology) approach angle, I might find it works as well as the ceramic for me.

Allen

[Blake]

Hello Allen

This is probably not the issue but ............Are you lifting the heel of the blade slightly when cutting a curve? It sounds like you are leaving too much blade in the leather for the sharper curve if you are bunching up the leather and getting drag.

I apologize if I'm off base here.

Blake

[Big Papa Leather]

Blake,

I think you are close, However I do not think I am lifting the heel as much as maybe not using enough angle.

Angle away, and not toward me.

I noticed that I have been holding the knife almost perfectly horizontal.

Allen

[Blake]

Are you pulling or pushing the knife? I know that sounds like a dumb question but normally the knife is pulled although a well known and respected Leather Artist pushed his.

I'm not sure exactly where Burnet TX is but if you are close to me you are welcome to come by and get a starter lesson and at the same time we can get your blades angled and sharpened correctly. If that isn't practical maybe Bob (Hidepounder ) could possibly post a photo of the correct way to hold and posistion the knife and blade.

Kind Regards

Blake

[Big Papa Leather]

Blake,

I do not think the issue is a starter one. Although I am new to this craft.

The blades are sharp as well, the angles are correct.

I was taught that the knife should be angled slightly away from the user as it is pulled through the cut.

Allen

PS Burnet is NW of Austin

[Blake]

Hello Allen

I Apologize, I didn't mean for it to sound negative that way. It just sounds like you are struggling a bit and I was trying to get an idea of what the issue might be so that I could offer some help. If the blade is dragging it is usually one of those causes.

I got a few nice clean sides from W&C a few months back and they were terrible to carve . The blade would start dragging within two or three cuts and a little soap would help but not enough to take away the misery and wear on the blades. W&C replaced the leather after a quick phone call so occasionally it isn't the knife at all.

The offer is open anytime that you are over my way to stop in and visit.

Blake

[Big Papa Leather]

Sorry if I sound as if I was scolding, I was just clarifying.

Believe it or not this thread has really made me consciously aware of my technique.

I have discovered a few flaws in my swivel knife usage. I thank those who spoke up.

I still intend on looking into different blades.

Allen

[hidepounder]

Scissormedic,

When I'm using a 1/4" angled blade I hold my knife almost straight up and down. I angle it away from me (toward the tip) in tight turns and angle it toward me (away from the tip) on long straight cuts. When using a flat blade, the knife will always be angled away or toward the cutting tip. The problem that I have is holding my the knife verticle in a curve....I have a tendancy to want to lean to the side which produces an undercut. It's a very bad habit I developed somewhere along the way.

After reading this thread it seems to me that you don't really have a blade problem. I think you are probably correct that your steeper ceramic blade is easier to run than your steel blade and you are just not accustomed to the feel of the steel. For what ever it's worth, I believe it is good to learn to use a knife with a large flat blade. I think it forces one to learn to manipulate their knife. Something along the lines of learning to drive a standard transmission before an automatic.

The other thing that thing you mentioned was depth of cut. It is not necessary to cut really deep. Your pattern dictates the depth of cut as you are trying to create an illusion of depth which is another subject in itself. The more refined the pattern, the shallower the cuts will be.

Hope this helps,

Bob