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Sharpening a 20 TPI saw

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Andy P Devon

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Hi All,
Just got myself a PAX Gent saw - 20 TPI.
It cuts but is not "sticky sharp".
Question is:- is it possible to give this a quick sharpen? By this I mean, one stroke of a saw file per gullet to refine the edge. Problem is I can hardly see the gullets!
I don't want to ruin a new saw by try to sharpen what can;t be sharpened - at least not until it is definitely dull. It's not a hard-point saw.
Anyone any advice or tips on refine the edge? I know the saw is not top-end, by any means, but hope to use it for many years as only a 'weekend' warrior'.
Thanks in advance,
Andy
 

MikeG.

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They're nice saws (I've got one), whether they're top end or not. Yes, they can be sharpened, but I reckon one of those magnifying lenses on a stalk with a built in light is about the only chance my eyes would have of doing it these days. I've only sharpened mine a couple of times, and it was pretty much by feel.
 

Jacob

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Yes, by feel. Helps to black felt tip first and you can then just see where you've been. You have to get the angle and the pressure consistent so it's best to zip up one side fast, turn, and zip up the other without pausing or changing stance etc
 

D_W

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feel and file with a tiny edge so that the gullet isn't any shallower than it absolutely has to be.

With teeth that small, as long as there aren't a bunch with flats on top, it really doesn't matter if you do a perfect job. The saw will still be easy to use.

One stroke per tooth is ideal. Color the teeth with a marker (I haven't seen any of the media mentioned above) in case you get distracted for a second. Many of the mid-grade saws now are fairly soft, so it won't take a heavy stroke even to sharpen them - just one moderate stroke and try to take care to make the stroke the same firmness from one tooth to the next - as if you're a filing robot.
 

Hattori-Hanzo

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Funnily enough I had a go at sharpening mine a couple of days ago.

Paul's video is a good reference to start from and I will echo what others have said about taking a very light pass and trying your best to keep them consistent. The teeth will have a good profile already so half to one full file pass will be plenty to get them sharp.
You will probably need a extra slim or double extra slim saw file so as not to open the gullets too much.

One thing I will add is to try and keep the file rake angle matched to whats on the teeth at the moment. If any thing a slightly negative angle may be better as the saw will cut smoother but slightly slower.

You can add a small length of wood to the end of the file to help you gauge the angle you need, just keep referencing the bit of wood to the saw teeth like you would viewing winding sticks to help maintain the rake angle.

I found adding to much of a positive rake made the saw too aggressive and notchy to use.

High light the teeth with a permanent marker really helps to see which teeth have been filed. Don't run the marker along the top of the teeth as you will ruin it's tip, instead run it along the side of the teeth and the ink will flow around the teeth nicely.

Go steady and take your time.
 

Derek Cohen (Perth Oz)

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Andy P Devon":2vct40vt said:
Hi All,
Just got myself a PAX Gent saw - 20 TPI.
It cuts but is not "sticky sharp".
Question is:- is it possible to give this a quick sharpen? By this I mean, one stroke of a saw file per gullet to refine the edge. Problem is I can hardly see the gullets!
I don't want to ruin a new saw by try to sharpen what can;t be sharpened - at least not until it is definitely dull. It's not a hard-point saw.
Anyone any advice or tips on refine the edge? I know the saw is not top-end, by any means, but hope to use it for many years as only a 'weekend' warrior'.
Thanks in advance,
Andy
Hi Andy

This is entirely realistic. You are not re-shaping the teeth, just touching them up.

The most important factors here are:

1. A fixture to hold the saw. Two pieces of wood alongside the blade, and then clamp in a vise, will do. Better is a saw vise.

2. Good light. The is really important. Along with magnifiers, if needed. There are simple head magnifiers with built-in lighting - I have one - and this is fantastic for seeing the teeth .... if you cannot see them, then you cannot sharpen them!

3. The correct file, which would be a 125mm long needle file. Ideally with sharp arrises.

4. A way to keep the rake angle constant. The can be as simple as a block of wood jammed on the end of the file, or a dedicated tool to show this (such as the one sold by Veritas)

I recommend also a black sharpie, and running this along the tips of the teeth to start. Then a very light jointing of the teeth with a fine file. This will show up the tips more easily .... sharp is when the shine is gone.

No need to redo the set at this stage.

Should be about 10 minutes work.

Regards from Perth

Derek
 

Orraloon

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All good advice so it is just finding a file that fits the tooth gullets and taking the plunge. I had to use a needle file on my gents saw as my smallest saw file was too wide in the gullet. Was something I had put off too long so after the saw skipping out of the cut and scarring some nice wood I had to bite the bullet. Worked out fine and at the rate of use my gents saw gets will do for years to come.
Regards
John
 

ED65

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Andy P Devon":2e7c8i9h said:
I know the saw is not top-end, by any means...
That really doesn't matter that much, and there's every chance it could last as long as coveted old saws. The steel used for saws is not particularly hard – the 'saw temper' of old can be softer than many a kitchen knife – so it's not a difficult target to hit, especially not these days.

So anyway you're sorted already in terms of whether you should (to which I heartily add my own, yes go for it!) and how to actually do it, but in terms of being able to see what you're doing I wanted to suggest trying cheap reading glasses, which are now widely available. Even those from the likes of Poundland seem to be acceptable.

One last tip, unless you can arrange to firmly clamp the saw quite high I'd recommend sitting down while you're doing this. Filing small teeth is tricky enough without adding backache into the equation :)
 

D_W

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If you get back to pre-circular saw, all of the saws should have pretty good hardness unless you get into second and third lines, but your point is accurate. the gents saws can be almost unhardened and work well. The blessing of the softer saws for one who can sharpen is that you'll rarely crack a tooth of setting, and your files will last as long as they exist until a corner rusts.

The smartness of a tooth on a very high end saw (just like a chisel, they'll hold the initial keenness better) is nice to have, but not a necessity, and you'll be a rare bird if any material part of building something is actual sawing. The time killer is pondering, and fixing mistakes made due to rushing.
 

Argus

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This is an interesting insight into Gents' saws and small-tooth saws in general.

Personally, I tend to avoid anything with more than 16 teeth to the inch for two reasons that have already been explained - I can't see 'em, even with good magnification and seldom need them. Add to that the problem with small files, obtaining decent needle files of the right cross section is very difficult.

The fact is that the cheap needle files available in sets are awful, so which files would people recommend for saws 20 points and upwards?
 

D_W

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Either luck into some Chinese file with an improperly thin edge or bite the bullet and buy proper needle files.
 

Hattori-Hanzo

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I sharpened my 18tpi saw with a new Nicholson extra slim saw file and it was just about okay, I think a double extra slim would have been better.

I wasn't overly impressed with the visual quality of the Nicholson compared to an old stubs saw file I have that's starting to wear but I've also just cut a new 17tpi plate with it and it seems to have done the job and for under a fiver it was worth a shot.

Bahco files seem to get good reviews but are a bit more expensive as do genuine Vallorbe but again they can be pricey.

I might treat myself to one of these in the near future though to see how they compare to the cheaper Nicholson.
 

Orraloon

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I am usually averse to sharpening anything smaller than 12tpi for the same reasons so thats why I put things off so long. It was however just the right kerf for doing fret slots so I was left with no choice. I may be stumped next time round as I dont think my eyesight would be up for setting it.
Regards
John



Argus":1217fqok said:
This is an interesting insight into Gents' saws and small-tooth saws in general.

Personally, I tend to avoid anything with more than 16 teeth to the inch for two reasons that have already been explained - I can't see 'em, even with good magnification and seldom need them. Add to that the problem with small files, obtaining decent needle files of the right cross section is very difficult.

The fact is that the cheap needle files available in sets are awful, so which files would people recommend for saws 20 points and upwards?
 

Argus

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MikeG.":fk7nc3jd said:
Orraloon":fk7nc3jd said:
I am usually averse to sharpening anything smaller than 12tpi ......
12? Really? That's really quite coarse. That rules out most tenon saws.

True that...... but the point most of us are making is that diminishing eyesight trumps pure size when it comes to sharpening. Even with the best lighting available, we can't see as clearly as was once the case.......
 

mrbadexample

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This is a handy thread. :)

I have acquired a bunch of woodworking tools which were once owned by my great uncle Fred. Amongst them is a tiny gents saw with, as best as I can tell, 26 tpi. He probably looked after it once but it's in a poor state now with very worn teeth. I'd like to have a go at getting it useable again.

I've never sharpened a saw before, but I was also given a tenon saw with 12tpi which I'll practise on first. I've watched Paul Sellers so all that's left is to have a go.

What I really need to know is what saw file I need for such a small saw, and if one file will do both saws. Any recommendations please?

Thanks.
 

Cheshirechappie

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mrbadexample":ekjn1z02 said:
What I really need to know is what saw file I need for such a small saw, and if one file will do both saws. Any recommendations please?

Thanks.
No, one file won't do both 26tpi and 12tpi. For the finer teeth, you'll need a three-square (triangular) needle file, preferably one of the shorter (140mm long) ones, and for the 12tpi something close to a 5" slim saw file.

Also, unless your eyesight is very young and sharp, you will find some sort of magnification will help with the smaller teeth. I'm short-sighted, so I take my glasses off and work close, but other people have recommended the budget-priced magnifying glasses sold as reading glasses, or a headband magnifier if funds permit. Good, bright lighting is pretty much essential, too.

Good luck with the small saw - getting all the teeth the same height will need a bit of care. You may need two or three goes - run a flat file along the tops of the teeth to level them up if you don't get it spot-on first time, then try again with the three-square.

P.S. - This is a long video (over 2 hours!) but it goes through all aspects of saw sharpening in great detail, and is well worth the effort of watching. It covers things in much greater detail than Mr Sellers does.

https://www.youtube.com/watch?v=u-_MF2Mnxwc
 

mrbadexample

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Cheshirechappie":noqs7yzt said:
No, one file won't do both 26tpi and 12tpi. For the finer teeth, you'll need a three-square (triangular) needle file, preferably one of the shorter (140mm long) ones, and for the 12tpi something close to a 5" slim saw file.
Thank you. I've found a suitable needle file (3" long cutting surface), so I'm actually in a position to have a go before getting to the tenon saw.

Should I wait and practise on the easiest one first? :?: That doesn't sound like something I'd normally do. :roll:
 

Cheshirechappie

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The usual advice is to practice on something with larger teeth before attempting a fine-toothed saw, but I suppose if you can successfully sharpen a 26tpi saw, you'll be able to tackle anything saw-shaped! And if that's what you've got the tools for, why not have a go? If the first attempts are not that good, just joint the toothline straight, reshape the teeth, and have another go.

(Do have a watch (or two) of Andy Lovelock's video first, though. You'll have a much better idea of what you need to do, and how to go about it, after digesting it.)
 

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