Thumb jimping

[TacticallySharp]

Here's a photo of one using the checkering file from Jantz. It's a 20 lpi file.

 

[mike miller]

I'm getting to the point where I do the 20 line cut then do a half round on either side with a 5/32 round file. It sure makes a secure stop.

 

[Justin Presson]

I'm getting to the point where I do the 20 line cut then do a half round on either side with a 5/32 round file. It sure makes a secure stop.

I have seen some knives like that and it looks good. I will likely pick up a 20 line at some point.

 

[Brian.Evans]

Here is how I do it.
http://www.bladeforums.com/forums/showthread.php/1272965-How-I-Jimp-a-Spine

 

[MisterE]

If you have access to a lathe you can add jimping to a hardened blade very easily.

You need a thin cutting disk, (the ones I use are 4 inches diameter and 1mm thick) and a suitable arbour to mount it in the lathe chuck. I had a cut off saw arbour which fitted and I mount the cutting disk between two smaller cut off blades to keep it straight.

Mount your blade in the toolpost ensuring it is on centre and perpendicular to the disk

Cut each notch with the cross feed and index along with the axial feed. You can vary the pitch and the depth as you wish.

It is important to measure the depth of cut from when the disk first touches the blade. The disk will get smaller as you go and your cuts will get progressively shallower if you dont. Also cut slowly to avoid warping the disk.

 

[Dennis Morland]

I do it just like Brian Evans. I also use the Bruce bump file guide. He should write a book entitled, "101 uses for my file guide". It is a great tool for many tasks. If you do not have one - get one. It helps with plunge lines, jimping, lining things up, all kinds of stuff. Very well built and extremely useful.

Here are a couple pictures of the jimping that I have finished. I use the Jantz tool with 20 lines per inch. You are only limited by your own imagination.

DeMo

Plain:

With filing:

45 degree angle:

 

[slatroni]

'm getting to the point where I do the 20 line cut then do a half round on either side with a 5/32 round file. It sure makes a secure stop.

I like to do the same thing. Here is one done with a 20 tpi from Brownells.

 

[jmforge]

When I bought my checkering file a couple of years back, I had to buy a 30 lip because the 20 lip ones were just not in stock anywhere. 30 works, but 20 would be better and I plan to get one soon. Another "cut down" a 20 lip file to 2-3 rows on an EDM machine and says that you can do "inside curves" of fingers groves down to at least 1/2 inch across with the "new" two line file. It just takes longer than doing 20 at a time, but the full sized file only really works on flats or "outside" curves. My thought was to cut the sides parallelogram shape so you could get 2 kins on one said and maybe 3 or 4 on the other to speed things up on bigger arcs. The files cut on both sides and are "safed" on the edges.