Frustration with the round knife

[jbird]

Howdy all and good day

So after using and using the round knife my bone is this I don't have any trouble geting it sharp but its the grab of the surface below I have poked around this question and I am wondering is there a surface I can cut on that dosent grab or do I just muscle throw this any and all input is wanted thanks all

Josh

Edited March 19, 2009 by jbird

[Tkleather1]

Howdy all and good day

So after using and using the round knife my bone is this I don't have any trouble geting it sharp but its the grab of the surface below I have poked around this question and I am wondering is there a surface I can cut on that dosent grab or do I just muscle throw this any and all input is wanted thanks all

Josh

I have had this same problem with my cutting surface, I use a hdpe sheet for my cutting surface and found that less muscle was the answer. If you get your knife very sharp then you shouldnt have to use wo much downforce to cut the leather. I fought and fought myself for a long time trying to figure out what was going wrong and found that I was jsut using too much down pressure.

Hope this helps

[Rawhide]

I have had this same problem with my cutting surface, I use a hdpe sheet for my cutting surface and found that less muscle was the answer. If you get your knife very sharp then you shouldnt have to use wo much downforce to cut the leather. I fought and fought myself for a long time trying to figure out what was going wrong and found that I was jsut using too much down pressure.

Hope this helps

I found that the regular plastic cutting boards at wally world work great. It's soft enough, not to damage the blade, but doesn't have a grain for the knife to try and follow. If you're using a cutting mat, it will 'grab' the blade and make the knife harder to push. A good way to tell if your knife is sharp, insert it into the leather and pull the leather into the knife, if it glides through, it's sharp.

[jwwright]

Personally, I seldom put downward force on a round knife, and don't use a "rocking" motion. I use mine to push forward through the leather. The knife does not come into contact with the surface of the table very often. JW

[Tkleather1]

Personally, I seldom put downward force on a round knife, and don't use a "rocking" motion. I use mine to push forward through the leather. The knife does not come into contact with the surface of the table very often. JW

that is what I was trying to say, but you say it better

[jbird]

well that must be it to much downward thrust.

But I still am wondering with that small amount of force how do judge if you have cut all the threw the leather.

Josh

[bruce johnson]

Josh,

That is the biggest problem I had starting with a round knife was knowing where that tip was. I thought I had to keep it pushed down. Once someone explained to me that the slicing action kept the blade down, it was a lot easier. I likewise use a piece of HDPE on my cutting table. I pretty much use mine like JW. Some guys make cuts off the edge of the table, and I do that for blocking and trimming stiffer leather sometimes. Some guys will cut on glass too. There is some debate on that, and I'll let someone else slug out the merits of that. I skive on glass sometimes.

The biggest problem I have is making tighter inside curves. I catch the blade tip in the cutting surface and snap off that corner. I have an older smaller pointed (Philadelphia pattern?) knife I mostly try to remember to use for these curves. Doing them on glass would prevent that.

[hidepounder]

When I'm on the cutting table I lift my leather so that my knife doesn't come in contact with the table. Someone told me that I shouldn't do that because it is dangeous, but that is what I prefer to do. I always rough cut out of the hide and then take the piece back to the bench where I dip it in water, slick it, and then cut to my lines. While cutting on the bench I use a different knife, on a cutting board made that white poly/plastic? material they use for commercial cutting boards. When it gets too carved up, I sand it down smooth with a belt sander. I use glass to skive on...it saves my knife and allows me to skive very thin. I broke my skiving plate a while back and have using my bench top which is a chemical lab counter top. It works okay.

I discovered that it is very handy to have different round/head knifes for different functions. I keep a small Rose knife that never touches anything but wet leather, I use a Bill Buchman knife to rough cut out of the hide, a small Gomph for general purpose cutting at my bench and a large Gomph for skiving on the bench. I don't NEED all these knives, I'm just a tool-aholic, but it seems like my knives all cut better and last longer doing different functions. (it's probably all in my head!). The biggest trick of course is getting them REALLY sharp! That's what takes all the muscle out of cutting.

Bob

[TrooperChuck]

I hated trying to make small diameter inside cuts with my round knife. Then, somewhere I saw a hint about using a leather punch to cut out those curves. I got a set of large diameter circle punches, they go up to 3/4 inch, and I since I started using them to cut out tight curves I've found the sun shines brighter, music sounds sweeter, and my wife hears fewer naughty words coming from my shop.

[Luke Hatley]

TROPPER CHUCK................ now you are using your head for something

than to seperate your ears.........

you will find out that there is an awful lot of things that will work for you.

i did..........

[jbird]

thanks all for your input very helpfull, and chuck I use those punches all the tim in fact I made some out of pipe.

Josh

[TrooperChuck]

LOL... the old guy who taught me to make saddles used to say that the only thing my head seemed good for is a place to hold my hat! Fortunately, I found this forum and all the folks who post in it, and now my head is getting filled with all kinds of new ideas.

I love this place.

[Bree]

Josh...

I am usually not in a big hurry so I cut the leather in multiple passes. When I am down to the last pass or so my pressure on the round knife is very slight and the cutting board doesn't really matter. I have been using Novolene which I got from Weaver. It is a thick poly used for clicking. It is very tough, smooth and slippery so it provides little friction to the knife to catch. I like it better than my old poundo boards or the self healing mats that I have used over the years.

I am nowhere near the leatherworker that Bob is but I find it to be unsafe for me to lift the leather when using a round knife. I prefer the slick poly surface, going in multiple shallow cuts, and opening the cutting kerf a bit rather than lifting the leather off the cutting surface. That round knife is very dangerous if you lose control of it. I don't trust myself. Heck I sometimes want to wear Kevlar gloves when I cut with it. I don't but the thought has crossed my mind more than once.

[Todd]

I cover my table with a sheet of "puckboard" (same stuff used to line hockey boards) purchased at my builder supply store. It helps the blade glide nice even when i do cut through the leather. It is relatively cheap for a 4X8 sheet so I replace it when it does get cuts or tracks that the blade can grab.

[jbird]

Thanks all for your input and help.

Josh

[Go2Tex]

Ah yesss... the round knife cutting issue. First let me emphasize the already mentioned factor of sharpness. Whatever technique you use, a dull blade will be a problem. Been there done that. Until you can shave the back of your hand with it, it ain't sharp enough.

Really firm, thick skirting is about the hardest thing to cut with anything or any method. I just finished cutting some Hermann Oak parts and I tell ya, I was back to the sharpening bench a couple times and it still was a pain. I forgot my little trick I use on Wickett and Craig drum dyed which is to use candle wax. Also works on stitching awls. The knife was sharp but the leather seemed really dry and the cut line just wouldn't open up. The leather was really grabbing my knife blade.

On those tight curves I also use the strap end punch or hole punch but you can manage a good tight cut with the head knife if you drop the handle down almost to the leather and use the smallest part of the blade. Make several passes using your free hand thumb to apply the forward pressure. I do this most of the time on heavy skirting because it gives me the greatest control of the knife.

The problem with this method is that if you don't keep your knife perfectly vertical and perpendicular to the cut each pass, you will have a bit of a jagged edge on the bottom.

[readytogiveitup]

Some makers use thick poly butchers cutting surface. you can get the thin kitchen cutting boards just about anywhere. The big heavy thick commercial grade tops at a restaraunt or butcher suppy. Can be sanded on occasion to keep it smooth and clean. but I learned on a soft pine board.