Thread: The "slightly less than ultmate" dovetail saw

I've got a shortened Disston I use, and it works OK. But it was shortened due to damage, do you actually need this shorter to do dovetails?. If weight's an issue then sure, but otherwise you just make work for yourself

I have a dovetail saw that I purchased a little while ago. As it is I have only used it once to make dovetails.

Prior to that I was using a tenon saw to make the dovetails. I recall in high school we used tenon saws for almost ever application. I suspect that the school could not afford more then one type of saw.

Originally Posted by andrewr79

do you actually need this shorter to do dovetails?. If weight's an issue then sure, but otherwise you just make work for yourself

That's a very good question. Dovetail saws seem to typically be in the 8-10" range, but why are they that short? Is there any reason why an appropriatly set up 12" saw would be inappropriate or less effective for dovetails?

Damage wise, the main thing will be removing that 5-6mm in blade depth...

You can cut perfectly good dovetails with one of your existing saws.
If you want to modify one you could: take off some length, or not; take off some depth in the blade, or not; file the teeth rip, or not; joint off the teeth and recut them to 15tpi-20tpi filed rip, or not.
lots of options.
I'd just reshape the teeth, file them with a rip pattern and finish with a light set and sharpen.
Then, provided you stay on the waste side of the line, you'd be set.
Happy dovetails.

Originally Posted by NZStu

That's a very good question. Dovetail saws seem to typically be in the 8-10" range, but why are they that short? Is there any reason why an appropriatly set up 12" saw would be inappropriate or less effective for dovetails?

Stu, the only reason I can suggest for smaller saws for dovetails is that it's easier for some of us to weild a smaller saw accurately. I favour one of my own saws, whch is about 220mm long and has about 45mm of useable blade width. However, there is plenty of debate on the topic, & what suits one person is not necesssarily what the next person likes.

Reshaping a blade is easy. Clamp between two bits of straight steel & whack of any excess with a 1mm cutoff wheel in your angle grinder. It should come as clean as a whistle, but any small dags can be cleaned up with a flat file. I recommend 15 or 16 tpi, with a fair amount of -ve rake for easy starting (~ 8 degrees works well for me) & a fine set. I've found by trial & error that a set that gives a kerf around 12-15% wider than the saw plate suits me very well for d-tailing.

To me, the bigest problem you have converting that old S&J is that the handle isn't optimum. The grip is a bit high, and the angle ditto. I like the grip to be a bit more vertical, and a bit lower down, which helps me 'feel' where the saw is going, better. The handle as-is is ideal for use about bench-top height. Of course, you may not be as visually challenged as I am, and not need the work up so high when cutting dovetails!

My 2c
Cheers,

I was lucky enough to bring along a really buggered S&J back saw to the recent TTTG Saw Sharpening workshop on Sunday just passed. It has two lots of teeth, existing at about 12tpi and then someone had decided it needed to cut quicker so they had cut teeth at about 5tpi for at least 3/4 of the blade. I pulled it out of the bag when our instructor, Bob, asked "Any questions?" I though I'd throw him a curly one. Turns out it wasn't that curly at all. "No worries. Clean it up, we'll shear of those teeth and you can cut a new set".

And it was that easy. Went downstairs to the guillotine, crunch, crunch, no more teeth. Took my new toothless safety saw back upstairs and using another saw clamped against it as a template, notched the blade and then started cutting new teeth. By jingoes! New teeth. I left the workshop a very happy Virgil. I felt the same way I did when I sharpened my first saw and actually cut wood with it after lord know how many years.

So there you go. You saw is not a goner and can be quite easily converted to any style you want.

Cheers,
Virg.

Thanks all.

I'll get the teeth recut a bit finer than they are now and see how it goes.

Ahhh. Hilarity ensues.

I dropped the saw into the local sharpening place with explicit instructions to strip the teeth and recut to 16ppi, rip cut, with no set (so I can set it how I want it)

I picked it up to find that it has been cut to 13ppi, cross cut and with a reasonable amount of set.

I struggle to see how they could have deviated further from my instructions if they'd tried.

I'll take it back and have a grizzle, but honestly. That's a pretty poor effort by any measure!

Originally Posted by NZStu

Ahhh. Hilarity ensues.

I dropped the saw into the local sharpening place with explicit instructions to strip the teeth and recut to 16ppi, rip cut, with no set (so I can set it how I want it)

I picked it up to find that it has been cut to 13ppi, cross cut and with a reasonable amount of set.

I struggle to see how they could have deviated further from my instructions if they'd tried.

I'll take it back and have a grizzle, but honestly. That's a pretty poor effort by any measure!

Sadly, that's very similar to the experience I had when I dropped a saw in to my local place for re-toothing. Every. Single. Detail. Was. Wrong. I held a ruler against it, counted the teeth, then showed them what THEY had written on the order sheet. Oh, they said, yeah, that's not quite right, do you want us to shear the teeth off and start again? I told 'em not to bother. I didn't even get into the issue of rake angles for rip vs. crosscut.

I think most of their business is power tool blades - the hand tools stuff might be a bit too old-school for them to bother with much.

Yairs - it's all a bit frustrating, isn't it? I don't think it's going to get any better any time soon. The trades have long since switched to powered saws, leaving a small niche market for hand saws. The knowledge of relevant tooth profiles & sizes seems to have been lost very rapidly as the old staff have retired, so an era has passed.

The only solution is to start learning to do it for yourself. It may seem like way too much trouble for a few saws, but it's not all that difficult once you get down to it. (Says he who took about 40 years to get serious about sharpening saws properly! )

Cheers,

I have no worries about sharpening saws myself for the most part - so far I've done the saw in question (14ppi crosscut), my other tenon saw (12ppi rip), a couple of 26" Disstons (7ppi rip and 8ppi crosscut) and a 4 1/2 tooth Atkins (rip). I would class the rip saws as a success with all cutting nicely, but the two crosscuts did not wind up cutting smoothly.

Cutting a whole new set of teeth, on the other hand, is a bit more effort than I have the time, inclination or tools for right now!

I'm contemplating perhaps leaving this one at 13ppi crosscut and heading to the land of the rising sun for something to cut dovetails with...

Originally Posted by NZStu

...........Cutting a whole new set of teeth, on the other hand, is a bit more effort than I have the time, inclination or tools for right now!

Stu- I can understand the lack of time issue - the days never seem long enough to fit in everything plus a decent quota of shed time...

However, since you say you are pretty happy with your rip tooth filing, & that's what you want on a dovetail saw, you are more than halfway there. Cutting a set of teeth is nowhere near as difficult, nor does it take anywhere near as long as you might think. I could do a set like you want in under half an hour. And you don't need a single thing beyond what you presumably have already, i.e. a saw vise & the right-sized file. There are several posts on the Forum illustrating the various techniques people have used. I prefer the simplest - a paper template (RayG has posted a PDF with every size you could possibly want), and a short piece of wood to jam the end of the file into, for maintining the correct rake angle. Some prefer using an existing set of teeth as a template, and I think it's probably easier on your first try as it gives you more confidence, but for 15/16 tpi and bigger, I don't find it any easier than starting with the paper strip guide, which I stick on with a bit of shellac. You can use PVA, but get it off as soon as you can, because the water will rust nice clean saw plate very quickly.

I would also advise using a good-quality jewellers' ('needle') file for marking out because they have very sharp corners, making it easier to start the gullet in the right spot, & being second-cut, they chew through the metal very satisfyingly. A #3 cut is marginally faster than the finer #4 cut, but there isn't a lot of difference in practical terms - I tend to use the 4s for everything, now, for the sake of simplicity. I now use these files for sharpening any saw with a pitch of 15 tpi or finer, because I've found so much variation in the corner radius of the regular saw files.

As for your less than perfect results on the crosscut sharpening - I'm still working on my own technique after dozens & dozens of the darn things. There are two main reasons for roughness from my efforts - insufficient negative rake and uneven tooth heights. Rip saws with their straight-across chisel points are pretty easy, but having to watch bevel angles & rake angles at the same time seems to be a challenge - like walking & chewing gum at the same time! . I tend to lean a bit more heavily on the file in the wrong direction when filing one half, & have to really concentrate hard to keep them even. Some days it all goes beautifully - other days I end up with such a mess I have to joint the teeth off heavily & start over!

Getting a decent Japanese saw to get going with is a practical solution to the immediate problem - there are enough things to worry about when starting out cutting complex joints, without having to fight the saw. However, I dislike throwaway tools on principle, preferring those I can rejuvenate regularly. So keep at your sharpening technique - it doesn't take long to get results that are good enough for most purposes. Perfection is an impossible goal, anyway!

At the TTTG joint workshop last sunday we did handcut dovetail joints and there was a 16 TPI Veritas dovetail saw which seemed to be very popular as different people tried it out.
It is certainly on my to-buy list

Files are an issue - I can't get anything finer than a 4" slim taper easily, which is a bit too coarse for a 16ppi saw. I'll see if I can track down a jeweller's file. The other small issue is getting rid of the existing teeth - I don't have an angle grinder, so would have to do it with the jointer file.