Cutting Curves?

[MtlBiker]

3 minutes ago, zuludog said:

Well I, and no doubt yourself, am pleasantly surprised that you are able to order from George Barnsley directly at a reasonable cost; I have their head knife and it's very good

There's just one thing though. It's fairly straightforward to make a basic knife for leatherwork, but getting it very sharp, sharp enough to cut through leather easily, brings you into The Law of Diminishing Returns as it requires more and more careful sharpening, usually by hand, and so becomes expensive

So to keep the costs down, traditional makers such as Barnsley only provide a basic cutting edge; you are expected to do the final  sharpening and polishing yourself, and you buy the knife on that understanding. There are several videos about sharpening a round or a head knife, and once you've done that, usually all you need for regular use is a strop, or occasionally a light sharpen

You'll probably want to make a sheath for a round or head knife, again there are a few videos, as well as for using the knives themselves

Thanks for the tips about the sharpening.  We use a fine whetstone at my work to sharpen tools but I've never used a strop.  I guess I'll have to make/buy one.  I do regularly sharpen my pocket and camping knives, as well as chef's knives.  So I expect moving up to a finer edge and strop won't be terribly challenging.

Can't help but laugh though, about making a sheath for the round knife...  It reminds me of an old Harry Belafonte song, "There's a hole in the bucket, dear Lisa, dear Lisa..."  The song goes on and on about what should he use to fix it, then how will he cut it, how how will he sharpen the knife, and the stone is too dry, and Lisa says he should wet it, which brings us right back to the hole in the bucket.  I guess you'd have to hear the song to see the humour.  Anyway, what should I use to cut the sheath for the round knife? 

Here's a link to a really old YouTube video of Dear Lisa.

Cheers!
 

 

[zuludog]

1 hour ago, MtlBiker said:

Thanks for the tips about the sharpening.  We use a fine whetstone at my work to sharpen tools but I've never used a strop.  I guess I'll have to make/buy one.  I do regularly sharpen my pocket and camping knives, as well as chef's knives.  So I expect moving up to a finer edge and strop won't be terribly challenging.

Can't help but laugh though, about making a sheath for the round knife...  It reminds me of an old Harry Belafonte song, "There's a hole in the bucket, dear Lisa, dear Lisa..."  The song goes on and on about what should he use to fix it, then how will he cut it, how how will he sharpen the knife, and the stone is too dry, and Lisa says he should wet it, which brings us right back to the hole in the bucket.  I guess you'd have to hear the song to see the humour.  Anyway, what should I use to cut the sheath for the round knife? 

Here's a link to a really old YouTube video of Dear Lisa.

Cheers!
 

 

Yes, I know the 'hole in my bucket' song; it was a regular campfire song when I was in the Scouts, years ago.

As I mentioned, there are several videos on sharpening a round or head knife. For a new knife firstly I used a couple of oilstones with oil, then fine wet & dry paper, 2,500 - 5,000 - 7,000 grit with slightly soapy water, then a strop. I maintain the edge with a strop or sometimes the wet & dry followed by a strop. Just one thing; for most knives you push the cutting edge along the stone in a straight line, but if you do that on a round knife you are liable to make a series of short straight sections or facets, when what you want is a smooth curve. So sharpen your head knife with a sort of constant elliptical motion, the videos will show this - and don't forget to do both sides! If not the blade will be prone to veering of the desired line

Use the round knife to make a sheath for the round knife! Or a utility knife will do the job. Use the knife itself, or stiff card for a  template/pattern There are several videos for sharpening, & making the sheath - those by JH Leather and Ian Atkinson are good, but there are others

You can buy a strop, but it's easy & cheap enough to make your own, again there are several videos; but get a proper stropping compound, green chromium dioxide is as good as any. When the strop turns black you know it's working, because that's the steel that has been removed from the blade

Edited September 9, 2021 by zuludog

[zuludog]

You'll be tired of hearing from me! I was trying to make a properly composed answer to your questions, but really, if you watch videos on sharpening & using a round knife and the sheaths, and making & using strops you'll see enough to pick things up and see how its done

Edited September 9, 2021 by zuludog

[Hardrada]

8 hours ago, MtlBiker said:

A "plate, a bowl, a lid, anything that has the right curve to it" just didn't appear in my kitchen or garage.

This, maybe?

https://www.leevalley.com/en-ca/shop/tools/hand-tools/marking-and-measuring/marking-accessories/32536-flexible-curves

 

Before I had the round knife, I got this for curves:

https://windfiredesigns.com/Tools/CircleTool/index.html

 

8 hours ago, MtlBiker said:

Couldn't find the knife in Canada with a Google search, but Amazon US has one.  Is this the one you use/recommend?

Yes, that's the one. I got mine from Abbey England. Rocky Mountain Leather has the Vergez Blanchard for $99: some might prefer the VB since it's not bevelled. I saw that RM has their own brand round knives now too, but I don't know where they're made, so I can't recommend them... yet.

Edited September 9, 2021 by Hardrada

[tsunkasapa]

9 hours ago, MtlBiker said:

Surely you couldn't make two long parallel straight cuts, like for a belt, without using a straight edge as a guide.

You certainly could, but it's much faster to just use a strap cutter.

[bland]

14 hours ago, MtlBiker said:

Did it take long to master the round knife?  I can see that it should make cutting curves easier, but I'm surprised at your statement that with one you can also make long straight cuts without a straight edge.  Surely you couldn't make two long parallel straight cuts, like for a belt, without using a straight edge as a guide.

I would not say that I have mastered the round knife.  It was a little scary to use at first.  I'd use it for a while and then put it away for a while.  Probably for the last 6 months I use it most of the time.   Making long parallel cuts would be a challenge.  I still generally use a strap cutter or draw gauge depending on the leather thickness for belts and longer straps and I usually cut multiple at a time. 

I have used my round knifes to get the initial straight edge on a side or double shoulder.   I have used it for shorter straps for headstall and billets for bag closures.  Primarily the longer straight cuts are on bag bodies and projects like that. 

Being able to use one knife during cutout is definitely a time saver.   

[Hardrada]

1 hour ago, bland said:

I have used my round knifes to get the initial straight edge on a side or double shoulder. 

I haven't used it for that but I have indeed used mine for long straight cuts. It's doable: once the knife is embedded in the leather the embedding itself helps keep it on the straight and narrow.

RE: getting the initial straight edge, @RockyAussie has posted a video of his method. Funny, he uses the same brand and type of knife I have; and apparently it's the only thing he uses it for!

Edited September 10, 2021 by Hardrada

[Klara]

On 9/8/2021 at 7:45 PM, MtlBiker said:

Thank you!  I found that exact same knife on the Amazon Canada website but it says delivery estimated to be Nov 5th to 18th!!!  (But I want it NOW!!!  )

 

(This is about the straight knifes in the japanese style)

I've seen these knives on Aliexpress at various prices. If you still want one you might find one that gets to you before November. I want one now so I'll have a look (which won't help you as I'm in Europe).

I'm using a head knife for much of my cutting, an ex-kitchen knife with a rounded tip for some and a cheap pair of utility shears for some. I'm not perfectly happy with my curves, though. But straight edges with a head knife (or round knife, probably) are easy: Start the cut and then rock the knife forward, push and rock. The rocking is also excellent for chrome-tanned leather. For belts I've bought a strap cutter, though...

 

(Incidentally, it seems as if glaziers used head knifes for scraping putty from old windows. I've asked Friedrich Herder - makers of the Don Carlos knives - where to buy their head knife in the EU and they've sent me to a supplier for windows and doors.)

 

 

Edited September 10, 2021 by Klara
Removed erroneous info and added correct

[RockyAussie]

4 hours ago, Hardrada said:

RE: getting the initial straight edge, @RockyAussie has posted a video of his method. Funny, he uses the same brand and type of knife I have; and apparently it's the only thing he uses it for!

Close to true but not quite. Here's an old picture video I did way back showing how I use it for shaving and I do use it a lot for belt length size cutting. With it I can cut straight down through 5 straps at a time which is pretty handy when you gotta do 50+ at the same size length. https://www.youtube.com/watch?v=K7xMEtBUl6s

shoot I forgot to say I'm the good lookin one on the right at the end

Edited September 10, 2021 by RockyAussie

[zuludog]

2 hours ago, Klara said:

(This is about the straight knifes in the japanese style)

I've seen these knives on Aliexpress at various prices. If you still want one you might find one that gets to you before November. I want one now so I'll have a look (which won't help you as I'm in Europe).

I'm using a head knife for much of my cutting, an ex-kitchen knife with a rounded tip for some and a cheap pair of utility shears for some. I'm not perfectly happy with my curves, though. But straight edges with a head knife (or round knife, probably) are easy: Start the cut and then rock the knife forward, push and rock. The rocking is also excellent for chrome-tanned leather. For belts I've bought a strap cutter, though...

 

(Incidentally, it seems as if glaziers used head knifes for scraping putty from old windows. I've asked Friedrich Herder - makers of the Don Carlos knives - where to buy their head knife in the EU and they've sent me to a supplier for windows and doors.)

 

 

I ordered that cheap Japanese leather knife, from Amazon I think, and it did take a few weeks to arrive but was OK when it did. I've also made my own from an old plane blade

Recently I've been using Etsy to buy leatherworking tools and other items. You see the price in £, which includes any import duty, delivery time & shipping cost; I expect you would get the same thing for your country and currency. I've never had any problems with delivery, and the quality of the items is what you might expect for the price; and there is usually quite a range of makes & choices

Search Google for 'Etsy - Japanese leather knife'  'Etsy - leather edge bevelers' 'Etsy - leather stitching chisels' 'Etsy - round knives' and so on. There are some well known makes like Palosanto and Seiwa, and some less well known. To a certain extent you have to make an intelligent guess about the quality. I usually buy one item, and if that's OK, go ahead and buy others of the same make. Although I haven't bought anything from them, I've heard good reports of Kemovan products, especially their bevel edgers. Etsy also offer 'Since' leather tools, which are Tandy's new up market range. I've also seen Vergez Blanchard tools and Fil au Chinois thread, which are surprisingly difficult to obtain outside France

Yes, I've seen the Osborne head knife sold as a lead knife, for making stained glass windows.