Swivel Knife

[Davm]

I have a swivel knife that doesn't seem very sharp. Tandy model.  I bought a clamp on guide for sharpening but I don't seem to be able to get it very sharp. If you are supposed to strop the edge thn I am assuming you need it very sharp. Any help appreciated.

[Tugadude]

32 minutes ago, Davm said:

I have a swivel knife that doesn't seem very sharp. Tandy model.  I bought a clamp on guide for sharpening but I don't seem to be able to get it very sharp. If you are supposed to strop the edge thn I am assuming you need it very sharp. Any help appreciated.

There are likely several videos on youtube that address sharpening swivel knives.  Which Tandy model?  They have several.  Is it angled or square?

 

Edited September 15, 2021 by Tugadude
added info

[battlemunky]

Sharpening a swivel knife blade is just like sharpening any other blade. If you can't or don't know how to sharpen a regular knife, you can learn a lot you can apply to either depending on which version you start with. YouTube is full of sharpening videos as Tugadude posted one.

Keep your angle constant (use the holder you picked up) and make sure that you are keeping it equal on both sides. You should get a burr to form on one side that you then work the other side down to until it forms a burr, then step up to higher grit sandpaper/stones and you should have it ready. It isn't always a quick process so take your time and pay ayyention.

Check out some videos and try it out.

[chuck123wapati]

the wide angle wont ever get super sharp like a knife so if that's what your trying for it wont happen but it will get "sharp" in swivel knife terms.  it only has to cut the leather about halfway through which is why the angle is like it is. I test mine by trying to bevel the edge of a piece of leather if it will trim a bevel it is sharp. 

[YinTx]

Getting the angle identical every time you take it to the stone is not easy.  Bruce makes it seem easy, but that is years of practice.  Using a simple swivel knife jig really facilitates getting this right.  When you don't get it right, the bevel will lean, and you may have multiple bevels, instead of one flat mirror.  Some of the older blades are rougher than the one he is working on, and take a lot more effort to get sharp.  However, they will easily cut you or anything once you get it sharpened and stropped.  Sometimes I'll use it to cut out the shape of a piece I've just tooled because it makes small complex curves easy to cut.  It'll go right through 10 oz leather - I take it almost all the way, then let it dry and finish with a round knife or one of my other leather knives when I am done.

I spent a few hours on these to get them to this point, while not perfect they are fun to use and cut very smoothly.  The one on the left could use more work on the 5000 grit stone before stropping again.  As far as I know, these are all old Tandy blades, and cut as well or better than a Barry King I tried out once.

YinTx

[chuck123wapati]

4 minutes ago, YinTx said:

Getting the angle identical every time you take it to the stone is not easy.  Bruce makes it seem easy, but that is years of practice.  Using a simple swivel knife jig really facilitates getting this right.  When you don't get it right, the bevel will lean, and you may have multiple bevels, instead of one flat mirror.  Some of the older blades are rougher than the one he is working on, and take a lot more effort to get sharp.  However, they will easily cut you or anything once you get it sharpened and stropped.  Sometimes I'll use it to cut out the shape of a piece I've just tooled because it makes small complex curves easy to cut.  It'll go right through 10 oz leather - I take it almost all the way, then let it dry and finish with a round knife or one of my other leather knives when I am done.

I spent a few hours on these to get them to this point, while not perfect they are fun to use and cut very smoothly.  The one on the left could use more work on the 5000 grit stone before stropping again.  As far as I know, these are all old Tandy blades, and cut as well or better than a Barry King I tried out once.

YinTx

beautiful! those nice polished bevels do their share for a nice smooth cut as well, makes the blade slide along without grabbing. 

[Davm]

Thanks everyone

 

[oltoot]

Another 'trick' . Rather than try to acquire and then ruin a series of stones, get  a series of grit sandpapers from coarse to fine and lay a sheet of sandpaper down on your tooling or skiving place (big smooth spot) and back and forth with your blade in the little Tandy roller guide. When you have the metal 'scored' with a series of lines to  match the grit then repeat with a finer grit till you are down to emory paper and just polishing. Finish with hard strop and enjoy!

[Samalan]

On 9/16/2021 at 12:15 PM, oltoot said:

Another 'trick' . Rather than try to acquire and then ruin a series of stones, get  a series of grit sandpapers from coarse to fine and lay a sheet of sandpaper down on your tooling or skiving place (big smooth spot) and back and forth with your blade in the little Tandy roller guide. When you have the metal 'scored' with a series of lines to  match the grit then repeat with a finer grit till you are down to emory paper and just polishing. Finish with hard strop and enjoy!

I agree I use a piece of glass 3/8" thick 4"x 12 " with wet dry it works great I like to keep sharpening separate from other work as it tends to get a bit messy .

[YinTx]

24 minutes ago, Samalan said:

I agree I use a piece of glass 3/8" thick 4"x 12 " with wet dry it works great I like to keep sharpening separate from other work as it tends to get a bit messy .

+1 on all this.  I also use a bit of water with a couple of drops of dish soap for lubricant on the sandpaper.  Can take it all the way to 2000+ grit sandpaper, wet/dry 3M.  Finish on the 4000+ grit stone if desired, then strop for final polish.

also, I don't follow the roller back and forth, instead side to side, with the roller part OFF of the sandpaper.  It'll slide along just fine on the glass/granite.  This keeps the grain in the direction of the cutting action of the blade, and easier to control the burr for me.  I forget who I saw doing this but it was a game changer for me.

YinTx