Coping saws-- a cautionary tale

[Max Withers]

I have a lot of cautionary tales I don't have time to share here, but since there is so much dovetail action right now I thought I should mention this. Thanks to the largesse of some family members who live in Maine, I have a fancy new dovetail saw with a .015 plate. It works great!

However, when I finally used it to cut dovetails, I was unable to cut out the tails with my coping saw. I tried some stuff, even going to the extreme of putting in a sharp new blade, to no avail. Eventually I realized the kerf was too thin to turn the corner.

Now, a tiny forum-reading part of my brain started worrying about a new aerospace-grade coping saw, and how I could afford the extra cost for a wooden handle... but in reality, I just need a thinner coping saw blade. Where does one buy these?

(The immediate problem was solved by rekerfing the tails with a regular backsaw. Which maybe would have worked better in the first place. But then why do I "need" the fancy new dovetail saw?)

[Peter Evans]

I use a coping saw diagonally across the waste, and then cut back to the other corner. This leaves a very small triangle that is easily chiseled out. The coping saw is much quicker than a fret saw and no need to work within a narrow kerf

[Derek Cohen]

Hi Max

Peter is correct. You do not need to fit a thin blade to a coping saw if you remove the waste in two saw cuts. On the other hand, if you do want a blade to slip down the kerf, then you can get them from Tools for Working Wood. Then work well, but are wider than a fretsaw blade and cannot turn as tightly.

Regards from Perth

Derek

[Chuck Hart]

Olson blades they're sold on Amazon or straight from Olson. They make good blades

[Tony Zaffuto]

After I saw my DT's, I use the DT saw to make a "V" to the baseline (or close to it) takes a couple of quick cuts in the middle of the waste, leaving easy coping cuts to the important saw cuts. As far as the Olson blades go, the 18TPI work best for me. These are also the thinnest, working much better than the 15TPI stock blade that comes with the Olson saw.

[Jim Matthews]

Having cut the last dozen dovetails with a coping saw I can't help wondering if there's
a better way. At least a third of them have ragged shoulder lines from tipping the blade
away from me and going "too deep" on the far side of the board.

Chopping so many with a chisel aggravates my elbow, but the shoulder lines are tight.

The coping saw is a balky beast, I suppose that cutting straight lines with something that's meant to cut curves is the problem...

With 90 plus dovetails to cut in my next scheduled project, I fear I will stray off the reservation.
I just want square drawers that fit their openings, and this is a real time sink.

[Andrew Fleck]

Are you cutting to the line with the coping saw? I cut about a 1/16" above it with the coping saw and then pare to the line. It's a little bit time consuming, but I'm not good enough to cut a straight clean line with the coping saw.

[David Weaver]

Cheap coping saw (but one where you can rotate the blade), cheap coarse blade, straight down through the middle of a pin or tail cutting to the corner and then straight across.

Takes about as much time as it takes to use a fretsaw to go right across unless you have tiny pins, but the balance works out on the tails. You cover more real estate, but in the same amount of time and you can get the cheap blades at any local hardware store and they rarely break.

the handy part of that is that they have some set and if you need to actually cope something, your saw is already set up with a fast coping blade (cope something meaning like a plane handle or a saw handle or anything else you might do such a thing with).

[Derek Cohen]

Having cut the last dozen dovetails with a coping saw I can't help wondering if there's
a better way. At least a third of them have ragged shoulder lines from tipping the blade
away from me and going "too deep" on the far side of the board.

Chopping so many with a chisel aggravates my elbow, but the shoulder lines are tight.

The coping saw is a balky beast, I suppose that cutting straight lines with something that's meant to cut curves is the problem...

With 90 plus dovetails to cut in my next scheduled project, I fear I will stray off the reservation.
I just want square drawers that fit their openings, and this is a real time sink.

Hi Jim

The last time I needed to do a large amount of dovetails ( 12 drawers with 4 half blind pins at the front of each drawer, and 5 through mortices at the rear = about 140 dovetails), I explored what would be the fastest, most efficient method for both half blind and through dovetails. Keep in mind that the half blind dovetails were in Jarrah, which was a bugger to chisel out.

I wrote this up here: http://www.inthewoodshop.com/Furnitu...tDovetail.html

Essentially, I used a power router to facilitate the waste removal of the half blinds ...



This made it simple to split out the waste ...



There is more information in the article.

I use a fretsaw - not a coping saw - on drawer tails. There is not much waste to remove, and a chisel cleans up quickly.

It is when one is making a large number of through dovetails, such as a carcase, especially in hardwood, then it pays to saw the waste as close to the line as possible. A fretsaw does do this better than a coping saw - however good coping saw technique can balance out the equation since its thicker blade and coarser teeth cut faster.



Regards from Perth

Derek

[Brian Holcombe]

If you split out the waste it comes out very quickly. To set the shoulder I chisel just ahead of the line for the first chop, the bevel forces it into the line.

I also angle the chisel slightly toward myself when chopping the shoulder. It leaves a shoulder which can compress slightly.

This is a bridle joint but the same idea applies;




And of course doing this work in a robe and slippers is an added bonus for any unfortunate witnesses.

[Frank Bizley]

If you split out the waste it comes out very quickly. To set the shoulder I chisel just ahead of the line for the first chop, the bevel forces it into the line.

I also angle the chisel slightly toward myself when chopping the shoulder. It leaves a shoulder which can compress slightly.

This is a bridle joint but the same idea applies;




And of course doing this work in a robe and slippers is an added bonus for any unfortunate witnesses.

Great simple explanation Brian, fantastic pics aswell.

[Jim Koepke]

I'm with Brian, chop them out.

If nothing else, now you have a reason for some fancy new chisel.

jtk

[Max Withers]

Ha, Jim, I don't believe in fancy new chisels, so that means I have to sharpen my rusty old ones.

I will compare my speeds on chopping and sawing straight down the middle.

Thanks for all the tips.

[Jessica Pierce-LaRose]

For me, it depends on the size, and the wood. Drawer tails, things in softer woods, chopping and splitting is easy. When the spaces being removed get larger, I tend to saw first. I usually chisel or knife out a little V along the baseline *before* I remove the waste - this seems to guide the coping saw, and gives me a good place to start paring from, and really just gives me a good visual indicator amongst the saw dust of where I'm cutting with the coping saw. Just make sure you remove that waste from the correct part of the joint. . . .

I usually run the coping saw down one of the dovetail saw cuts, and start cutting maybe halfway down the DT saw cut, going in the same direction, putting just a little english on it so it veers into the waste and then once it's started grabbing, start my turn. With a good blade, you can figure out pretty quick what kind of turn you can make. I usually hold the saw so that I know it's probably a little higher on the back-side of the cut just to be on the safe side, but I usually make the backside of the cut the non-show face, so it's not the end of the world if I go over. I get left with a little high spot in one corner of the tail, but it's usually narrow enough that a couple of paring swipes with a 1/4" chisel remove it. I get close enough to the line with the saw that I can remove the waste quickly by paring, often only using hand pressure if my blades are sharp and the woods softer, although a mallet makes the work quicker, of course.

Anything smaller than like a 1/2" or so at the baselines, however, and I just go with chopping - when the force is concentrated in such a small area, with a small chisel you can remove a lot of material quickly.

I honestly don't think my method is very fast, but it's how I learned (somehow - god knows) and it's been working for me, so I just go with it. Fortunately, I don't have to worry too much about speed, but I suppose I should be moving out of my comfort zone and also try and focus on efficiency.

I think where the chop-not-saw approach really gains speed is when you're doing a lot of it at once. If I'm working on one board, I don't think sawing slows me down much over chopping. But there's always more than one board in a dovetailed anything, and more when you start looking at multiple drawers. When you see folks like Klausz (was it Klausz I'm thinking of?) gang up a whole stack of staggered boards, and just chop their way halfway through each socket in the whole stack, and then flip the whole thing around and finish it up, you realize that's were you can really gain some efficiency, only having to make a few work-holding adjustments for a whole stack of boards, as opposed to clamping each individual board in a vise, saw it, then unclamp it and set it up for paring, and then tackle the next one - even if you tackle all your paring tasks at once, over the coarse of a whole project, the clamping up for sawing adds up quickly. I don't mind, because at this point in a project, I'm often just taking a little bit of time here and there doing one drawer an evening around whatever else I've got going on, but if I actually wanted to get anything done, I'd be looking at it different . . .

[Max Withers]

I'm often just taking a little bit of time here and there doing one drawer an evening around whatever else I've got going on, but if I actually wanted to get anything done, I'd be looking at it different . . .

Yeah, at this point I'm just sneaking out to cut maybe one or two tails at a time. I can see How I might get good at this is I did it every day...