Cutting Around A Template Which Blade?

[DavidL]

When cutting around a template or scribed line.

How does each knife compare to prevent the corners from "flaring out". Which is more "suitable"?

1. Clicker knife (concave profile)

2. Round knife (convex profile)

3. utility knife (straight profile)

My awl has a rounded convex point profile and can cut templates better than my sharpened utility (prevent the edges from creating that little nub).

[gmace99]

Depends what leather you are cutting.

I use me clicker on thin leather and my round knive if it is saddle flap leather

I have never used a concave blade in my clicker knife. My clicker blades are straight like my paring knife. I make my own blades out of good quality hacksaw blades.

[Art]

It is easier to see (and hence follow) a line with a head knife. For really intricate "inside" cuts, the No. 11 scalpel or a sharp pointed clicker knife is good too. For tight curves, a big head knife is hard to turn, but those small ones with the shallow profile are better. Everything has to be bleedin' sharp.

Art

[DavidL]

Thanks for the help.

I figured out the way to cut these corners by paying more detail by how i move my blade. First I took your advice art and took 5 mins to sharpen the blade to bleeding sharp. How it was before wasnt as sharp as I could of had it. When just reaching the edge I slowly tilt the blade against the template at the same time lower the blade (larger cutting surface) putting more pressure. The twist keeps the blade from moving off pattern.

I have to test it more to find out if it is the proper way.

[bgl500]

Keep in mind I don't own one or have yet to try but the industrial knife looks really useful.

https://www.youtube.com/watch?v=BptBUaXd7rM

[TinkerTailor]

One thing to consider also is the cutting surface. While they can make a more accurate cut and are the best in inside corners, pointed knives tend to dig into the surface you are cutting on, adding drag, and in the case of wood grain, causing the blade to wander.

If I am cutting on wood or any softer surface, I would use a round, or convex blade shape. It will sink into the base material less and won't tend to follow the grain as bad. If necessary, i will switch to a straight or concave for the corners.

If I am on a poly surface, I would use straight or concave all the time for accuracy.

[DavidL]

Interesting. I never considered the cutting surface to be a factor.

[howie696]

Keep in mind I don't own one or have yet to try but the industrial knife looks really useful.

https://www.youtube.com/watch?v=BptBUaXd7rM

I bought from Weaver the same knife was about half the Tandy price

[DavidL]

Heres a response I've gotten from a reputable source.

The Clicking Knife was introduced by the shoe industry & curved & straight interchangeable blades are available. When cutting firm leather, (medium to thick) the blade point penetrates the leather & the cutting is done by the area of the blade just above the tip as you pull the knife towards you.

As you can imagine only a small area of the knife is in contact with the leather, Now if you try to cut soft leather or linings with a hooked blade it results in a raged edge,but a flat blade will ensure that a long area of the blade is in contact with the materials being cut. ( That is providing you are not raising your hand to high & reducing the area of contact.

As for cutting round corners, it is impossible to cut round small corners with any knife, & your best option is to cut past the corner then cut round the rest of the pattern. you will have square corners but keeping the pattern in place you can cut round the corners afterwards. you can also chip the corners away from the edge of the pattern with a straight blade.

The Large straight knife is seldom used nowadays, The round knife is now mainly used for shaping strap points & cutting strap ends & it is used in a rocking motion on the surface of the strap & when it is used by a saddler to cut round curves free hand it is pushed & not pulled.

[Art]

Who or what is the reputable source? If you include it then you should credit it.

Art