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View Full Version : Setting and sharpening really fine (16-20 TPI) dovetail saw teeth.



Luke Dupont
10-21-2021, 8:21 PM
Hi guys.

So, in the past, I have had great success sharpening and setting tenon saws around 10-12 TPI, and even made my own bow saw blades before.

I've used the screwdriver method, and I think I've also used a hammer and nail before (I don't remember too well if that worked out) to set teeth. I had great success with the screwdriver method though.

However, I picked up this little dovetail saw recently... I think it is around 18tpi perhaps. I sharpened it with an "Extra Slim" saw file, and it's sharp now, but for the life of me I cannot set it.

The teeth are really shallow with kind of wide gullies between them (maybe my saw file is not narrow enough?) making this even more difficult. I tried the screwdriver method, and it requires far too much downwards pressure and inevitably just pops out and results in my hand flying into the saw blade...

Then I tried the hammer + nail approach, and it is just totally ineffective. The teeth don't get set / bent.

I even tried going after them with pliers, and could not get a strong enough grip on them.

I then tried carving a little groove in a thin piece of metal to grip the plate, and allow me to twist ala the screw driver method. That worked, except it too had the tendency to pop out, and upon popping out it chipped off the tip of one of the teeth. Yikes!

How the heck do you guys sharpen and more importantly set really fine saws? I feel like the hammer technique should work, but I need something that doesn't "slip" so badly off the teeth. That, and it's easy to lose what tooth you're on.

I'm tempted to just file all of the teeth off and re-cut them at 12-14ish TPI... Though, I really would like to be able to sharpen and set teeth finer than that.

Tyler Bancroft
10-21-2021, 9:39 PM
Tried a nail set with a divot on the tip? Should stay on the tooth much better than a nail.

Luke Dupont
10-21-2021, 10:41 PM
Tried a nail set with a divot on the tip? Should stay on the tooth much better than a nail.


When you say divot, you mean like a hollow in the tip?

That sounds like exactly what I need if so... I'll have to look and see if I can find something like that.

Is there a specific term for these that I can search for online?

Stu Gillard
10-21-2021, 11:15 PM
When you say divot, you mean like a hollow in the tip?

That sounds like exactly what I need if so... I'll have to look and see if I can find something like that.

Is there a specific term for these that I can search for online?

Hi Luke.

'Round head nail punch' will get you there

Jim Koepke
10-22-2021, 1:34 AM
Stanley nail set, pack of three:

466789

Check the ends for being hollow. Vintage examples do have a dimple in the end.

They are good for setting the heads of finishing nails below the surface. Also needed when blind nailing or 'invisible nails':

466790

The arrows are pointing at invisible nails.

jtk

Derek Cohen
10-22-2021, 2:50 AM
Luke, for tenon and dovetail saws, I have 4 saw sets: 2 x modified Eclipse 77 and 2 x Stanley 42X. Each is set up with different amounts of set - I have experimented for years, and found what works best for different rake angles and teeth sizes. This makes sense to me as I have several backsaws. However, if I had just one, I would still use a pistol grip type, either the Eclipse or the Stanley (they have pros and cons), as I find this more predictable in use.

I might add that I consider setting teeth as very important. This can make-or-break a fine sharpening session. Too little set and the teeth will not cut smoothly. Too much and the blade can wander and leave a rough finish.

Regards from Perth

Derek

Luke Dupont
10-22-2021, 10:01 AM
Thanks guys. I ordered a 1mm because the 3mm one I found in the home center was far too large still.
Couldn't tell (can't tell) online if it was indented or flat, but I guess I'll find out.

For good measure, I also ordered a tenon saw with 11TPI, because I know I can sharpen and set that, and I'll need it anyway...

Jim Koepke
10-22-2021, 12:16 PM
Luke, for tenon and dovetail saws, I have 4 saw sets: 2 x modified Eclipse 77 and 2 x Stanley 42X.

As Derek mentioned a saw set can be made to work well with small teeth. One of my Stanley #42X saw sets has had the plunger filed to hit a small tooth. My finest saw is 15ppi.

There was an article many years ago with a few paragraphs on setting teeth. The author suggested gluing a small splinter of wood to the face of the setting plunger for setting small teeth.

jtk

Mike Allen1010
10-27-2021, 11:39 AM
FWIW, I strongly agree with Derek and Jim – A purpose made saw set is absolutely the way to go as it will provide much more consistent results than the punch method for most folks.

For Fine pitched joinery saws (with lots of small teeth +12 PPI also importantly very little set is needed as compared to full-size panel saws ), it is helpful to file both the hammer and the anvil of whatever saw set you’re using to fit the size of the smaller teeth and the limited slope of the anvil needed for adding .004” of set.

I’m sure there are those who can very successfully set joinery saws with a punch, but I’m not one of them. once you set up your saw set appropriately I think you’ll be surprised how much more frequently you’re willing to sharpen/tune your joinery saws to get peak performance.

Cheers, Mike

Luke Dupont
10-28-2021, 8:40 AM
Thanks everyone.

The nail setter method wasn't working for me -- I was still either shearing off the teeth, or not moving them at all, with only the very occasional perfect amount of force and position on the tooth enabling me to actually bend it. I abandoned that method as I was just doing too much damage.

I did find a saw set which seems to work well enough on the smallest setting (12) -- the saw being apparently 15 TPI as I count it.
Any excess set I can easily remove between two hammers or in a vise, and the hammer on the saw set seems just small enough to handle it. I guess the set is made for Japanese saws with their narrow teeth. Lucky!

Now I just need to joint, repair, and resharpen the saw and give it another go.

I also ordered some new old stock extra slim taper nicholson files, to see if they work any better than the crappy modern file I was using which is already starting to lose its bite, and I suspect probably cuts larger, rounder gullies inbetween the teeth than it should.