Saw files: What to buy?

[Trevor Goodwin]

I had a quick read on Paul Seller's Blog, and he says the saw files are 6-sided so that they last longer. If they were a true triangle, the edges that come to point and do a lot of the work would dull quickly. If the edge is a small flat/rounded section, the teeth are stronger so the file will last longer.

In my mind I don't see why having rounded gullets instead of pointed should cause a problem?

[Pete Taran]

Trevor,

Sellers does some good work, but his theory on files isn't part of that accomplishment.

I have quite a few vintage files made by Disston and others. I've always considered that it's important to compare what they did back in the day when people made their living with such tools to what we produce today. While methods of production are certainly different, the characteristics of a perfect tool are not. The stuff they made 100 years ago was designed the way it was designed because it worked and it was efficient to use AND produce. If you had all three legs of that stool, you had a great selling product. No one used more files than Disston did 100 years ago, and they didn't make a consumer line and a shop line. They made one line for everyone.

Guess what? Those files come to as sharp a point as you can imagine. All the good files I've used come to sharp points as well. It is one of the things I look for when considering how good a file is.

Some things to consider. Why do people think the sharp intersection of the two sides does more work than any other part of the file? If you think about it, it really doesn't. If you are filing down into a triangle space, you are deepening the gullet, but you are also removing material from the sides of the teeth to bring the teeth to a point.

As to what does it matter if the bottom has a flat, it matters! If there is a flat at the bottom of a gullet, then by geometry, the tooth is not as high as it should be. Smaller teeth carry less dust and they clog more. This is not as big a deal on larger saws like rip and coarser crosscuts, but if you are filing a 14 point backsaw, I'm here to tell you if a saw file has a flat on the edge, you might not even be able to file the teeth as the width of the flat all but removes the teeth. Anyone who has filed a small toothed saw knows what I'm talking about!

If I were to give any advise, I would advocate just the opposite of what the various blogs say. Get the keenest edged file you can find that holds up for one sharpening per side. If it does and doesn't lose it's teeth, you have found a great saw file.

Happy Filing,

Pete Taran

[Isaac Smith]

In my mind I don't see why having rounded gullets instead of pointed should cause a problem?

For larger teeth, it's usually not a problem, but can become so as the teeth get smaller and the corner radius proportionally larger. In some cases, the corner radius becomes larger than the front edge the tooth, throwing off the geometry of the tooth (i.e., the take angle of the tooth is governed the radius of the corner, not the flat face the file as it should be).

Gullet capacity also decreases, which again, is really only an issue with small teeth.

The diagram below shows this effect, although it doesn't show the radius edge of the file coming all the way up the front edge of the tooth.

[Pete Taran]

Isaac,

I like your graphic. It illustrates the point perfectly. The only thing I would add is imagine if the top file had a sharp corner. If it did, the height of the teeth would be taller than the result shown. This is always a good thing.

Regards,

Pete

[Trevor Goodwin]

Thankyou Pete and Isaac, you have illustrated your points beautifully.

[Trevor Goodwin]

Has anyone tried Pferd saw files? They have them in their catalog, but I can't find anywhere to buy them. http://www.pferd.com/images/WZH_22_201_E_en_72_dpi.pdf

Pferd make good stuff, I imagine their saw files would be good quality, at least better than Nicholson.

[Luke Dupont]

Trevor,

Sellers does some good work, but his theory on files isn't part of that accomplishment.

I have quite a few vintage files made by Disston and others. I've always considered that it's important to compare what they did back in the day when people made their living with such tools to what we produce today. While methods of production are certainly different, the characteristics of a perfect tool are not. The stuff they made 100 years ago was designed the way it was designed because it worked and it was efficient to use AND produce. If you had all three legs of that stool, you had a great selling product. No one used more files than Disston did 100 years ago, and they didn't make a consumer line and a shop line. They made one line for everyone.

Guess what? Those files come to as sharp a point as you can imagine. All the good files I've used come to sharp points as well. It is one of the things I look for when considering how good a file is.

Some things to consider. Why do people think the sharp intersection of the two sides does more work than any other part of the file? If you think about it, it really doesn't. If you are filing down into a triangle space, you are deepening the gullet, but you are also removing material from the sides of the teeth to bring the teeth to a point.

As to what does it matter if the bottom has a flat, it matters! If there is a flat at the bottom of a gullet, then by geometry, the tooth is not as high as it should be. Smaller teeth carry less dust and they clog more. This is not as big a deal on larger saws like rip and coarser crosscuts, but if you are filing a 14 point backsaw, I'm here to tell you if a saw file has a flat on the edge, you might not even be able to file the teeth as the width of the flat all but removes the teeth. Anyone who has filed a small toothed saw knows what I'm talking about!

If I were to give any advise, I would advocate just the opposite of what the various blogs say. Get the keenest edged file you can find that holds up for one sharpening per side. If it does and doesn't lose it's teeth, you have found a great saw file.

Happy Filing,

Pete Taran

When cutting my own teeth, I had quite some difficulty cutting the teeth accurately when getting as fine as 12+ tpi with the rounded edged files that I used, and I imagined that sharp corners would make the job so much easier, as you could start off with a much sharper and better defined tooth placement. The rounded edges just want to stray all over the place, and you simply can't be accurate with them.

Using a hacksaw does help, but due to the kerf of the saw blade itself, it's still tough when you get into the region of 16tpi or so.

I've never tried a saw file with sharp corners, but I really want to now. Does anyone still produce them?

[lowell holmes]

Actually, they have all of the popular brands of saw files