Thread: Saw File Hardness Measurements

I was reminded of the discussion I engaged in here about the Sapphire coating which I think is aluminumtitaniumsiliconcarbonitride and is blue (https://en.wikipedia.org/wiki/Titani...minium_nitride). Vanadium carbide coatings are similar in hardness (Tool Dynamics · The Application of Vanadium Carbide) and the finish is silver.
I think the Corinox is something else however given that its lower in hardness than either of the above. There is a Corinox S.R.L in Cordoba but I haven't dug in very far.

It's hard to believe that file edge has done so much work, Rob, I cannot see any evidence in those pics that it's been put to a saw! At this rate, it's already earned it's cost, and you've still got two untouched edges to go. As you say, almost too good to be true....
Cheers,

Originally Posted by IanW

It's hard to believe that file edge has done so much work, Rob, I cannot see any evidence in those pics that it's been put to a saw! At this rate, it's already earned it's cost, and you've still got two untouched edges to go. As you say, almost too good to be true....
Cheers,

Yes, a pity for you Ian that they don't come any finer than cut #2.

Originally Posted by FenceFurniture

Yes, a pity for you Ian that they don't come any finer than cut #2.

True! I wonder why? Simply no demand for the finer cuts, or is the process incompatible with fine teeth?

P'raps I could put my prejudice agin coarser teeth aside and give one a go, they certainly seem to win in a cost/benefit analysis. Right now though, I'm not thinking needle files. With this weekend in Ballarat coming up, I'm about to have a little practice run sharpening a couple of my handsaws that need attention after a recent workout. I'll be trying some other interesting files that have recently come my way ....

Cheers,

Yeah, keen to hear feedback on the Toledo files (aka Tome Fetiera, but stamped BluDan ).

IIRC Coraddi don't have any needles finer than #2. Mind you, this could take it back to my earlier proposal of forming with #2 and then a finishing stroke with a #6. Did you ever test that #6 Vallorbe I sent you (at enormous cost of course)? I was keen to see if it produced a noticeably sharper tooth.

I'll send you some of each to try Ian. I think you'll come to like the Corinox.

Originally Posted by FenceFurniture

...... Did you ever test that #6 Vallorbe I sent you (at enormous cost of course)? I was keen to see if it produced a noticeably sharper tooth.

Oh dear! You are becoming as forgetful as I am, Brett!

Yairs, I tested it at the time & I did report back to you. It must've slipped past your consciousness, but we also talked about it during a phone conversation, as I recall, & I said it was a nice little file, but probably not worth the hassle of getting (& keeping track of) yet another saw-file type. I've got a drawer-full of the bleeding things of various sizes and because I do sharpening & saw making in bursts, with sometimes long intervals in between, it's hard to keep them sorted!

To reiterate, what I found was that although the #6 did have a nice, smooth action, I couldn't see much difference in surface quality compared with a #4 (using a head-band magnifier), and certainly couldn't detect any difference in the way the saws cut. I think it would be highly unlikely that you'd 'feel' a difference, anyway, given the very small difference in 'scratch' pattern of the two files. What you might find is that the cleaner edge off the 6 holds its sharpness a bit longer. This is true for any cutting edge, and fairly easy to demonstrate on a chisel or plane blade, but difficult to impossible to assess on something used as erratically as a saw, with such variable times between sharpenings.

A #4 leaves a pretty clean surface in any case, and when doing the final pass over the teeth, I finish with a very light, short stroke to 'polish' the surface, & when you do that, any difference between a 4 & a 6 is further reduced. The #6 cuts remarkably quickly for such a fine file (as double-cut files are wont to do), & if they were readily available, at the same cost, they would be good sharpening files. However, they ain't readily available, and since the #4s are, and strike a very good compromise between speed & quality, they are my current choice. If you happened to have a batch of 6s at a good price, I'd take a dozen or so off your hands, for sure, but from a purely practical point of view, I don't think they are worth going to extra trouble to obtain.

OK, back to making window casements....
Cheers,

Nah, I was just checking to see if you were consistent.

Actually I did fogetted, prolly because I gave up smoking yesdy.

The long delayed and awaited box of saw files from Corradi arrived today. After counting the spoils I engaged in a torture test of the single 8" Corinox thee square file I ordered. Here's the file at 1X.

8 inch Corinox file.jpg


I used the edge on the right of the magnified picture to sharpen three handsaws in the 4 to 6 PPI range.

Used edge of 8 inch Corinox file.jpg

Some damage to the teeth is apparent under 10X magnification but the file is still cutting strong. This file was about $20US delivered so if 9 or 10 saws can be sharpened per file these are pretty cost efficient files.

Were the corners the right sharpness Rob (i.e. not too fat)?

Quite nice for a three square. The apex is just under 0.6 mm wide. I'll be in touch via PM as I get the other parts of the box assembled.

Does this mean
There could be a file at the end of the tunnel soon[emoji846]

Matt,

I think so, at least for saws <6 ppi and >12ppi. The Iridium files are at least as good as the old Nicholson Black Diamonds that I have and much better than any new file I've ever bought.
In this order I purchased a box of OO cut Corinox needle files (51 lpi), they are excellent for forming teeth quickly or restoring rusted teeth,

Cheers,
Rob