help-cutting thick leather

[vector]

Hi all,

Been playing with various projects and keep stumbling at the cutting time.

I work out a design say for a multitool knife sheath, using inkscape or some other pc cad system and print out the shape. Including the fold over retainer and belt holes etc.

I dampen the leather and draw over the template thus marking the leathers outer extremities. then I start to cut.. so far straight lines are fine I use a ruler or something to cut against. But hand cutting with a stanely knife or surgeons like craft knife around corners just never looks nice. As in symmetrical with the other side.

I also notice I tend to have trouble maintaining a "square cut" thru the leather. Sometimes under cutting the underneath for example.

Im working on 3mm (8-9oz). I have tried a light score, followed by further heavier scoring runs until it cuts thru and often get slithers of leather where the blade hasnt perfectly tracked the previous score. I have also tried one single heavy cut all the way thru and thats not always pretty either

Do I need a better knife?

a better proceduer

or just more experience

I have had great success with using a bottom layer of 3mm and then moulding a thinner top layer like 1-2mm around the knife. I use a fret saw to cut a mold out of wood that the knife fits into.Case the leather, wrap the knife in cling film, put the leather over the knife and clamp the wood mold over the top. Next day wood off and there is a perfectly formed leather fit around the knife. I then glue n sew that onto the thicker base. But once again the cutting or trimming to finish off the excess top and make it all look symetrical just defeats me. Looks like a 2 year old has been at it with sicsors

[kevinhopkins]

Hello Vector,

It's possible that you might need a better knife... I'm sure we all have our preferences, but in our shop, we actually use a silly little exacto knife for a majority of cutting. But we also have an old 5 in one for cutting large heavy things, and of course, there's times when the ol' utility knife is used. But the main deal is having a sharp blade. Keeping it buffed on a wheel with rouge on it makes a huge difference. And on tight curves, sometimes it's good to use a round drive punch where it gets tight. Depending on what you're doing, sometimes it can be helpful to have the edge of your leather off the edge of your workbench, and cut from the bottom. Like i said, we'll all have our preferences, and I'm sure there's a lot more ways and ideas out here...those are just a quick few.

Kevin

[DG Leather]

i use a rotary knife...but man it dont cut so well.....What kind of exacto knife would a guy use?

All exacto/utility knives i know suck.....I used to frame houses and they would even break on plastic lol

[rdb]

Buy and learn to sharpen a round/head knife. Then learn to use it. It will be the best leatherwork investment you make.

[MADMAX22]

Buy and learn to sharpen a round/head knife. Then learn to use it. It will be the best leatherwork investment you make.

I agree, once you learn to sharpen them and keep them sharp they are great. Some people dont like them or dont like using them so its up to the person.

Mine I finally learned how to sharpen it and it glides thru 10oz leather with ease.

[westernblingbling]

I am fairly new at this, and I too was having problem with the Stanley and craft knives. What I discovered that works much better for me is to case my leather and use my swivel knife to make the first cut at least half way through. Then I use a craft knife with a good sharp blade. My cuts are much cleaner and I find I have much better control over the swivel knife. And the added bonus is it goes much faster too.

[vector]

.. case my leather and use my swivel knife to make the first cut at least half way through. Then I use a craft knife with a good sharp blade.

Thats a neat tip Ill give it a try then look at round heads..

What about trimming it all after?

Say ive glued and sewn two pieces together and want to trim the offcuts of leather back and close and parallel to the stitching.

I was thinking of using a dremel and sanding drum to finish the edge but it just seamed to burn.Im concerned a knife will slip into the work area.

Im so used to scraping or filing or sanding wood to get perfect fits...this leather is a challenge

[Randy Cornelius]

I remember the days when I used a utility knife to cut leather, bought a round knife, learned to use it and keep it sharpe, never looked back, still have a utility knife, use it to open the boxes my leather and hardware come in..

I was looking at Utube videos the other day and some saddle maker was on this video and he was saying how a utility knife was the only way to cut leather, said some use a round knife but he did not like them. I think the only ones that do not like round knifes are the ones that are afraid to learn to use one and keep it sharpe, I think I have 5 or 6 now.

Randy

[vector]

ok Il bite, are there any links to tutorials on how to use and or sharpen a round knife?

[Randy Cornelius]

Yes, maybe someone can find them and post a link, not sure I can but I will look

[Randy Cornelius]

Here is a video that I found on youtube that is good, I would not say it is great but it shows you the basics of how to sharpen a round knife and how to strop it. I do it a little different but then everyone you talk to will have thier own way. I use 3 different stones, course, fine and them I have an old razor hone that my grandfather used on razors. Then I use a power strop I made. I have a leather belt for my 4 x 36 inch belt sander that I have rouge on that works great for polishing a blade of any kind. I hope this helps.

Randy

[UKRay]

Here is a another video that I liked: http://www.youtube.com/watch?v=vpWNJOCYA1A

I think this one says it all...

[Dwight]

Just a couple of comments: one being a question. What is the big deal on cutting the leather?

If you are doing a finished project, you will want to sand and finish the edges anyway, so why go into a big sweat on whether the "cut" is 90 degrees or 85 degrees, . . . or even on the line you will want to see as the finished project?

Secondly, . . . if you have a Stanley razor knife, . . . you can make an improvised strop for it with a 1 by 4 inch piece of scrap leather, . . . rub it with jeweler's rouge, . . . and keep your razor knife sharp with it. Most of the cuts I make would try the patience of anyone with a round knive as they are sharp curves, etc, . . . so my choice has been the razor knife that I keep "razor" sharp (which is about 3 times as sharp as a new blade right out of the box) with my improvised strop.

But, . . . regardless of what you use, . . . if it is dull, . . . it will not cut correctly. A sharp knife, . . . regardless of the kind, . . . is what you need.

May God bless,

Dwight

PS: If you really are dead set on perfect cuts, . . . on the line, . . . etc, . . . contact a band saw blade manufacturer through Google or something like that, . . . those that make custom blades will be able to make you one that has a razor edge on it, . . . you can put it on a regular wood or steel cutting band saw, . . . and you can cut leather as intricate as you want with a little practice, . . . and all your cuts will look great. If you do this, however, . . . you will want to be extremely careful with it, . . . it will take finger tips, knuckles, etc off so fast it is almost unbelievable.

Edited April 21, 2009 by Dwight

[Tkleather1]

I remember the days when I used a utility knife to cut leather, bought a round knife, learned to use it and keep it sharpe, never looked back, still have a utility knife, use it to open the boxes my leather and hardware come in..

I was looking at Utube videos the other day and some saddle maker was on this video and he was saying how a utility knife was the only way to cut leather, said some use a round knife but he did not like them. I think the only ones that do not like round knifes are the ones that are afraid to learn to use one and keep it sharpe, I think I have 5 or 6 now.

Randy

I too have seen that and had to laugh a little. I am by no means an expert at any of this but I personally think that a saddle builder who claims to be as good as that should at least know how to use the "proper" tools for the job. To me that is like a mechanic saying "well I know how to use that torque wrench but I prefer to use this pipe wrench and pair of pliers instead" Just doesnt seem real credible to me.

Use a round knife.

[Tkleather1]

Here is a another video that I liked: http://www.youtube.com/watch?v=vpWNJOCYA1A

I think this one says it all...

That puts it pretty clear to me.

[hidepounder]

Vector,

As you can see from the different posts, knife sharpening is the major issue here. Anything can be used to cut leather...if it's sharp! What you need to concentrate on is taking whatever type of knife you think you like to use and learn to sharpen it. What is sharp enough? A box cutter with a new blade is not sharp enough, a new knife with a factory edge is probably not sharp enough. There are many videos available on U-tube that are worth watching, and they all demonstrate different methods of sharping. It's a learning process that you must master in order to be able to continue enjoying your leather work.

I personally use a head knife and a small straight knife. I don't have any problems cutting curves or corners or wierd shapes in heavy leather with a head knife. A couple of suggestions....when cutting out of a side of leather, rough cut (cut it oversized) the initial piece out of the side. Take it to your bench, dip it in water, let it dry a bit, then cut it to shape on your bench. It is much easier to cut correctly from a small piece of leather than to try to cut your exact shape out a dry side.

I have to agree with Randy about using head knives and there is a good reason why most professionals use them. They are difficult to learn to sharpen, but if you get a good one and get the hang of it, you'll never go back.

Good luck,

Bob

[vector]

Thanks for all the replies people. Im probably being too harsh on myself in my leatherwork opening moves and getting down heartened. Ill check out some videos and and get busy sharpening some tools and try again.

Ill also have another go at sanding back the edges as this was my original intention. Maybe the dremel is just too fast and thus causing the burning of leather rather than sanding.

I also think that starting off making a sheath for a min multitool (70x20mm) was maybe making things a little hard on myself.

[MADMAX22]

Just a couple of comments: one being a question. What is the big deal on cutting the leather?

If you are doing a finished project, you will want to sand and finish the edges anyway, so why go into a big sweat on whether the "cut" is 90 degrees or 85 degrees, . . . or even on the line you will want to see as the finished project?

Secondly, . . . if you have a Stanley razor knife, . . . you can make an improvised strop for it with a 1 by 4 inch piece of scrap leather, . . . rub it with jeweler's rouge, . . . and keep your razor knife sharp with it. Most of the cuts I make would try the patience of anyone with a round knive as they are sharp curves, etc, . . . so my choice has been the razor knife that I keep "razor" sharp (which is about 3 times as sharp as a new blade right out of the box) with my improvised strop.

But, . . . regardless of what you use, . . . if it is dull, . . . it will not cut correctly. A sharp knife, . . . regardless of the kind, . . . is what you need.

May God bless,

Dwight

PS: If you really are dead set on perfect cuts, . . . on the line, . . . etc, . . . contact a band saw blade manufacturer through Google or something like that, . . . those that make custom blades will be able to make you one that has a razor edge on it, . . . you can put it on a regular wood or steel cutting band saw, . . . and you can cut leather as intricate as you want with a little practice, . . . and all your cuts will look great. If you do this, however, . . . you will want to be extremely careful with it, . . . it will take finger tips, knuckles, etc off so fast it is almost unbelievable.

Allthough I agree with some of what you say, I have not sanded any of my finished products. I dont currently have the facilities to do that. I make as best a 90degree cut as I can then bevel the edge and slick it. When I slick the edge I get it cased and this will form the leather into a nice rounded edge. With a round knife you can get pretty good shapes and such. On the really small corners or shapes for my projects I will use a straight blade that as you mentioned has been stropped to a very nice sharpness.

[badger]

I really don't understand all this bashing of anything that isn't a Round/Head knife.

I do 95% of my cutting with a utility knife. Randy, I have a Head knife and I'm neither ignorant of how to keep it sharp nor afraid of it or of using it.

This comes up again and again. We've had people boldly state that nothing else is the 'proper tool' and you cannot produce quality work unless you use one.

THIS IS SIMPLY NOT TRUE.

The proper tool is one that does the job you ask of it safely. Nothing more. I think a lot of the knife fascism comes from the Head/Round knife being seen as a kind of badge of office. I'm sure some feel they need to own and use one to feel like a 'proper' leatherworker.

I'm not saying that a Head/Round knife isn't an excellent way to cut leather, just that it isn't the only excellent way to cut leather.

Can we have a bit more 'live and let live' please?

Badger

[MADMAX22]

I really don't understand all this bashing of anything that isn't a Round/Head knife.

I do 95% of my cutting with a utility knife. Randy, I have a Head knife and I'm neither ignorant of how to keep it sharp nor afraid of it or of using it.

This comes up again and again. We've had people boldly state that nothing else is the 'proper tool' and you cannot produce quality work unless you use one.

THIS IS SIMPLY NOT TRUE.

The proper tool is one that does the job you ask of it safely. Nothing more. I think a lot of the knife fascism comes from the Head/Round knife being seen as a kind of badge of office. I'm sure some feel they need to own and use one to feel like a 'proper' leatherworker.

I'm not saying that a Head/Round knife isn't an excellent way to cut leather, just that it isn't the only excellent way to cut leather.

Can we have a bit more 'live and let live' please?

Badger

Honestly i thought this one was pretty civil as compared to some of the other threads on this subject. I dont think anyone was really bashing just kind of giving the opinions. I think it varies for different things and different preferences. For thin leathers utility knives are great, for thick leathers the sturdier round knife seems to suit me well but could be different for anyone else.

I think the biggest thing with this subject is its like any thread youll find anywhere on motoroil. You bring that subject up and the thread will turn into a 1000 post thread in a couple of days with no one correct answer.

Live and let live is a good idea though.

[David]

I'm going to get a lot of criticism for this; but here goes.

I wouldn't use a head knife if you paid me!

Without a doubt the worst cutting (for me) and most dangerous tool made for leather workers.

I do everything by the KISS principle.

I keep it simple. Every leather project I've done has been cut out using scissors. Please keep in mind I don't make saddles so most of my leather has been the 8-9 oz weight. You saddle makers, I understand the need for something else. But for those of us who are working in the lighter weight leathers, there is no need to use a cannon to kill a cock roach.

Go to Tandy and test out their premium leather cutting scissors. They are not cheap, but they work like a charm. We've all been using scissors since kindergarden so you won't need lessons on how to use them. Keep them perpendicular to the leather and you won't have accidental undercuts. You may also want to pick up a good pair of work gloves to pad your hand, but other than that.... give it a try.

David Theobald

Edited April 22, 2009 by David

[rdb]

I really don't understand the resistance to using a head/round knife!

Knife makers come in my shop, and are afraid of that blade...go figger.

I've been a tool person all my life. They have all been created for specific purpose. I have used box cutters, chisels, super shears and anything else I could get my hands on to cut leather...all because I did not want to learn the right tool. I cut myself a few times trying the head knife, and put it aside for a long time. Until I learned that out of the box, an osborne just wasn't sharp. Once I had that edge where it was supposed to be, and learned to keep my hands out of the way, well, a life changing experience occurred. Heavy leather, light leather, curves, straight lines, finishing intersecting cuts, straight edges...even mitering edges became a breeze...no more changing blades, no more beveled edges, no carpal tunnel, no more clenched teeth. I cut 1 oz or 12 oz, all in one pass of the blade. On the heavy stuff, I do go slower, but if you have to add more pressure, it AIN'T SHARP ENOUGH!

Like everyone else, I drool over those handcrafted head knives..lust would be too simple a phrase...lol, but to this day I use my 35 year old tandy osborne, with broken ferrule, and worn down blade. I cut seats, purses, wallets, and anything else in less time, more precisely, and no blood....lol.

[hidepounder]

I really don't understand the resistance to using a head/round knife!

Knife makers come in my shop, and are afraid of that blade...go figger.

I've been a tool person all my life. They have all been created for specific purpose. I have used box cutters, chisels, super shears and anything else I could get my hands on to cut leather...all because I did not want to learn the right tool. I cut myself a few times trying the head knife, and put it aside for a long time. Until I learned that out of the box, an osborne just wasn't sharp. Once I had that edge where it was supposed to be, and learned to keep my hands out of the way, well, a life changing experience occurred. Heavy leather, light leather, curves, straight lines, finishing intersecting cuts, straight edges...even mitering edges became a breeze...no more changing blades, no more beveled edges, no carpal tunnel, no more clenched teeth. I cut 1 oz or 12 oz, all in one pass of the blade. On the heavy stuff, I do go slower, but if you have to add more pressure, it AIN'T SHARP ENOUGH!

Like everyone else, I drool over those handcrafted head knives..lust would be too simple a phrase...lol, but to this day I use my 35 year old tandy osborne, with broken ferrule, and worn down blade. I cut seats, purses, wallets, and anything else in less time, more precisely, and no blood....lol.

AMEN Brotha!!!!

[hidepounder]

I really don't understand all this bashing of anything that isn't a Round/Head knife.

I do 95% of my cutting with a utility knife. Randy, I have a Head knife and I'm neither ignorant of how to keep it sharp nor afraid of it or of using it.

This comes up again and again. We've had people boldly state that nothing else is the 'proper tool' and you cannot produce quality work unless you use one.

THIS IS SIMPLY NOT TRUE.

The proper tool is one that does the job you ask of it safely. Nothing more. I think a lot of the knife fascism comes from the Head/Round knife being seen as a kind of badge of office. I'm sure some feel they need to own and use one to feel like a 'proper' leatherworker.

I'm not saying that a Head/Round knife isn't an excellent way to cut leather, just that it isn't the only excellent way to cut leather.

Can we have a bit more 'live and let live' please?

Badger

Badger,

I don't think anyone is bashing...I didn't read it that way...maybe some difficulty in understanding the resistance to learning to use a great tool...but not bashing! There is a reason that round/head knives have been produced exclusively for leatherworkers for the past 200 years. Most professionals use round/head knives for a variety of reasons...cutting shapes out of leather is just one of them. They are an excellent tool for cutting bevels on edges and are simply unsurpassed when it comes to lap skiving, especially on irregular shapes. Their design makes them incredibly easy to use to cut a staight line without the assistance of a straight edge, and you get to do all of this cutting away from your body, not toward it!!!!! It's really an all around knife!

I agree with you....a person should use what works best for them and I trully believe that! But if I'm asked, I am going to recomend learning to use a round/head knife because for me, it is the fastest, easiest and most efficient cutting instrament I own. Why recommend something you feel is inferior, right? I'll bet I have collected fifty different knives over the years, in nearly as many shapes and sizes, searching for that one knife that I can grab off the bench with confidence and a sense of gratification, knowing it is the best tool for the job! For me it's a head knife. It's one of the most important tools I own. I wish it hadn't taken me so many years to learn to use it, but it did, and now I tell anyone who asks, what a wonderful tool it is and why. There is a definite learning curve and I think people who have mastered that skill are enthusiastic about it and want everyone else to know what a joy that knife is to use use!

Anyway, that's my 2 cents...I'm not bashing...I'm just excited to share something that was difficult to learn!

Bob

[Randy Cornelius]

I really don't understand all this bashing of anything that isn't a Round/Head knife.

I do 95% of my cutting with a utility knife. Randy, I have a Head knife and I'm neither ignorant of how to keep it sharp nor afraid of it or of using it.

Badger

Badger, Vector started this thread and he asked about a better way to cut leather, I am sorry you took offense to our comments about the round knife. If you feel this strongly against a round knife, don't use one, use whatever is comfortable to you. I understand some of us get set in our ways. But I simply was telling Vector another way to cut leather. Seems I stepped on a nerve, I am sorry.

Randy