The table below shows our file recommendations for the files we sell. A little different than some recommendations. While we show these sizes as recommendations, the reality is we strongly recommend using the smallest file that completely covers the face of one tooth and the back of its neighbor.
For those who like to measure things, we have provided the nominal widths of one face of a given file. The recommendations largely overlap. Purchase as few files as you need to cover the saws you own or otherwise will be sharpening. No sense in buying every size file made to adhere expressly to our recommendations.
Please note that the Grobet needle file listed can be used down to about 15 ppi. I do not feel the extra expense is worth the tooth size gain below a PPI of 18. While the Grobet needle file has a face width equal to the Grobet 4 xx-slim, the face edges are a little bit smaller. This is what enables one to file smaller teeth than the 4 xx-slim and still maintain the largest tooth possible.
An example concerning no purchasing more than you may need. If I had two hand saws, a cross cut with 8 ppi and a rip with 5 ppi, I would buy only a 6″ slim. If I adhered to the stated goal above of using the smallest file I could use so the teeth would be the largest they can be, I would purchase two, a 6″ slim and a 6″ xx-slim.
By the way, the Xs refer to the “x” in extra. So a 6″ xx-slim would be a 6″ extra extra slim.
|File||Rec. PPIs||Nominal Face Width|
|Grobet Needle||18 ppi and up||5/32″|
|4 xx-slim||12 – 18 ppi||5/32″|
|5 xx-slim||11 – 15 ppi||3/16″|
|6 xx-slim||8 – 12 ppi||7/32″|
|6 x-slim||7 – 10 ppi||17/64″ (~1/4″ + 1/64″)|
|6 slim||5 – 7 ppi||21/64″ (~5/16″ + 1/64″)|
|7 x-slim||5 – 7 ppi||5/16″|
|7 slim||4 – 6 ppi||25/64″ (~3/8″ + 1/64″)|
|8 slim||3 1/2 to 5 ppi||15/32″ (1/32″ shy of 1/2″)|