File sizing

[Scoony]

I am in need of a small fine needle slitting file to cut tiny teeth. I am lookin at Grobet files and see that they have different cuts. 0, 2, 4, 6.  No explanation on what's fine and what's course. I am cutting tiny teeth at @ 20-30 teeth per inch into O1 drill rod that has been flattened and shaped.

Any idea on what the Cuts represent?

[Chuck Nickerson]

Of the cuts listed, 0 is the coarsest and 6 the finest.

If you're curious about tpi for each cut it shifts with the file length. That is a #6 cut 4" file had a higher tpi than a #6 cut 8" file.
I've not yet bothered to make a chart of the cuts, lengths and tpi's. Since I have the files I just try one.

It's also possible a #6 cut 4" round file has a different tpi than a #6 cut 4" barrette file. That would really blow up the chart.

[AHill]

One of the better references for file sizes and what tpi they will handle:

Norse Woodsmith Saw File Info

[Timberwolf]

I am in need of a small fine needle slitting file to cut tiny teeth. I am lookin at Grobet files and see that they have different cuts. 0, 2, 4, 6.  No explanation on what's fine and what's course. I am cutting tiny teeth at @ 20-30 teeth per inch into O1 drill rod that has been flattened and shaped.

Any idea on what the Cuts represent?

......................
I don't what you are planning to make, but you can use a smooth, flat file to IMPRESS "teeth" into a thin edge like a knife blade...Lay the edge of the "blade" on the surface of the file, then tap the "blade" into the file serrations with a small hammer..The drill rod "knife edge" will be soft enough to "saw" wood or aluminum without hardening, but if you harden it to about 62RC you can cut mild steel.
Just thought I would pass the idea along....It may help you with your checkering, if it's something you need for your gunstock...

[wood2woodknot]

[quote='AHill' pid='7716947' dateline='1549069539']
One of the better references for file sizes and what tpi they will handle:
______________________

CHECK YOUR LINK -- I ended up here when I clicked on it:

https://travel.state.gov/content/travel/...mport.html

[Mike Brady]

Looks like the Norse woodsman site was taken down by the owner, who name was Leif.  He was one of the early saw makers in the hand tool revival about 10 years ago.

[AHill]

One of the better references for file sizes and what tpi they will handle:
______________________

CHECK YOUR LINK -- I ended up here when I clicked on it:

https://travel.state.gov/content/travel/...mport.html

Fixed the link.  It works.  It is for saw filing, though, and not for the exact purpose the OP desired.

[Scoony]

Thanks all. I am making a checkering jointer. It is basically a piece of drill rod that is bent and flattened on the sides slightly, then filed to form a 60-90 deg cutting edge about 7/8" long. Tiny teeth are cut into it at a rate between 20-32 teeth per inch. It is used to straighten up lines in gunstock checkering. The tool itself runs about $40 so I figureded that I would give it a try to make one before buying one. Drill rod is cheap.

A checkering file would help with locating teeth, but they are expensive for a one time job. I can get the spacing using a 4" combo square setting the teeth 1/32" apart if my eyes can see that small (need to find one of those magnifier hood things) I need a small file that can cut those teeth and I think a small straight slitting file will do the trick.