Hand-cut dovetail issues

[KingwoodFan1989]

Okay, so I'm doing hand-cut dovetails for the drawer boxes on my project, and since a couple weeks ago, I've tried DOZENS of times to cut the pin board with only about 50% success. Specifically, when I go to cut one side of the pins, that side joins perfectly with the tail board pretty much 100% of the time (sometimes some filing is needed to loosen the fit, though). However, with cutting the other side of the pins, I'm always left with a curved cut which leaves an ugly gap on the outer face of the pin board when the two parts are put together. I'm not using any different technique or anything of the sort compared to how I'm doing the cuts that end up perfect. Has anybody ever experienced this? I'm almost beginning to wonder if I need a new dovetail saw because my results are consistently bad, and it's a phenomenon that has only started recently, but is it even possible for the saw blade to be warped in such a way as to only yield perfect cuts on one side of the cut and not the other? I don't know what to do, and I want to finish this project. I'm spinning my tires here. Any suggestions?

[TraditionalToolworks]

Okay, so I'm doing hand-cut dovetails for the drawer boxes on my project, and since a couple weeks ago, I've tried DOZENS of times to cut the pin board with only about 50% success. Specifically, when I go to cut one side of the pins, that side joins perfectly with the tail board pretty much 100% of the time (sometimes some filing is needed to loosen the fit, though). However, with cutting the other side of the pins, I'm always left with a curved cut which leaves an ugly gap on the outer face of the pin board when the two parts are put together. I'm not using any different technique or anything of the sort compared to how I'm doing the cuts that end up perfect. Has anybody ever experienced this? I'm almost beginning to wonder if I need a new dovetail saw because my results are consistently bad, but is it even possible for the saw blade to be warped in such a way as to only yield perfect cuts on one side of the cut and not the other? I don't know what to do, and I want to finish this project. I'm spinning my tires here. Any suggestions?

No, you don't need a new saw, get that out of your mind unless it is just a really poor quality saw. Do you have a picture of your saw, or can you tell us what type of saw it is? Maybe it just needs to be sharpened and/or tuned up.

From what you have said, I would take a guess that you need to follow your lines better. To be safe, try to leave the entire line and clean up with a chisel.

The wood will also make a difference, really hard woods are more difficult to make fit as the wood compresses less. Pine compresses a lot as it's soft, but Maple less so as it is much harder.

Also consider the problem is not with the pins, but could be with the tails. Dovetails need two piece to fit correctly.

Stick with it and keep practicing.

Cheers,
Alan

[Mike Brady]

You might try turning the pin board around and sawing the opposing cuts from the reverse side of the board.  Try relaxing the pressure on your saw when cutting and just provide smooth strokes while letting the weight of the saw do the cutting.  

Can you post some photos of the problem?

What saw do you have and is it sharp?

[KingwoodFan1989]

The saw I have is this one here: https://www.amazon.com/Rockler-Ikedame-S...kedame+saw

I'll go cut some more in a minute and see if I can get some photos. One of you said woods compress more than others and that could be the problem...I was getting the same results on my test boards and I tried it with both Red Oak and Yellow Pine, and I was getting nearly perfect results on both in weeks past, so why is Poplar giving me issues? VERY frustrating.

[Aram]

The saw I have is this one here: https://www.amazon.com/Rockler-Ikedame-S...kedame+saw

I'll go cut some more in a minute and see if I can get some photos. One of you said woods compress more than others and that could be the problem...I was getting the same results on my test boards and I tried it with both Red Oak and Yellow Pine, and I was getting nearly perfect results on both in weeks past, so why is Poplar giving me issues? VERY frustrating.

Are you using a light stroke? I mean extremely light, as in consciously unweighting the saw. You mentioned a curved cut. That can happen if you force the cut, which doesn't take much extra pressure with a dozuki.

[KingwoodFan1989]

Are you using a light stroke? I mean extremely light, as in consciously unweighting the saw. You mentioned a curved cut. That can happen if you force the cut, which doesn't take much extra pressure with a dozuki.

Well I tried again more carefully, and things look better, but I'll have to wait til tomorrow when I chisel the bottoms of the gaps on the pin board flat...last time I thought I had perfect joints I drove the tail board home and some gaps became apparent only then. Doesn't look like that will happen this time, but I'm still waiting til tomorrow to decide whether to proceed further with making the drawer boxes. I just don't feel like chiseling anymore tonight, haha!

I guess what's puzzling me is that it seemed to come so naturally before, whereas now I'm having to concentrate a bunch to get those cuts right. Hopefully it can work its way back into my muscle memory.

[TraditionalToolworks]

The saw I have is this one here: https://www.amazon.com/Rockler-Ikedame-S...kedame+saw

Ok, it's not your saw. Get that out of your mind. You should be able to cut decent dovetails with that saw, in 4/4 material, possibly 6/4, but not 8/4. The answer to whether your saw needs to be sharpened and/or tuned up is no, because you can't really do that to Japanese saws easily, you have a disposable saw for the most part. Nothing wrong with it though, it will be plenty accurate.

I'll go cut some more in a minute and see if I can get some photos. One of you said woods compress more than others and that could be the problem...I was getting the same results on my test boards and I tried it with both Red Oak and Yellow Pine, and I was getting nearly perfect results on both in weeks past, so why is Poplar giving me issues? VERY frustrating.

I was the one that mentioned about the wood compression. This is not your problem, from your description. The typical problem with compression of the wood is usually breaking the ends off. This is to say, the yellow pine will compress more than the red oak, and if you leave the joinery tight it is more likely to split the wood when you assemble.

Another thing to make sure of is to be accurate when you mark the boards. All of the small things matter when you're cutting joinery. There are various style marking gauges, find one that works for you and stick with it. Make sure the vertical lines (running parallel to the board face) and make sure you follow that line as you cut your tails or pins, depending on which board it is. Aram mentioned pressure, and that might be something for you to look at. Japanese saws need a really light touch, let them do the cutting, they're sharp. But be careful, the teeth are very brittle, and they usually break easily. One thing that's helpful when you start out, every night cut a couple dovetail joints. Just prep a bunch of small pieces of wood and each night cut at least one or two joints, more is better if you have the patience. After about a week you'll start getting the hang of it. You need to be persistent.


Alan

[Jim Waldron]

It could be much simpler that all the above:

Check your body position when you change from one angle to the other. If you keep your original stance when cutting the second side of the pins, you could well be pulling or pushing your arm and the saw into the error. I'd make sure of that first before you try a lot of other things.

And if that's not it, go slowly and try one bit of advice at a time; it you conflate six different suggestions at one time, you won't know which one was the important bit and make it more likely that the problem will recur when you don't maintain the full rigor of all of them.

[Mike Brady]

It could be much simpler that all the above:

Check your body position when you change from one angle to the other.  If you keep your original stance when cutting the second side of the pins, you could well be pulling or pushing your arm and the saw into the error.  I'd make sure of that first before you try a lot of other things.  

And if that's not it, go slowly and try one bit of advice at a time; it you conflate six different suggestions at one time, you won't know which one was the important bit and make it more likely that the problem will recur when you don't maintain the full rigor of all of them.

[Mike Brady]

All good advice so far.  Allow me to add a couple of things that may help. Cut your tails first. Whether you are practicing (essential) or actually making joints, always saw to your penciled layout lines, but not losing those lines in the saw kerf.  Why? because you need the lines to tell you how well your sawing followed the layout. Saw on the waste side of the lines, or ideally remove half of the line. You can always lightly pare to the lines if the joint is too tight, but there no fixing a loose joint. 

You can do the same thing by substituting blue tape and a sharp knife for pencilled lines.  You only need to do this on your second half of the joint, the pins.  knifing the profile and then peeling away the tape in the waste area leaves a wall of tape which you want to use as the starting point for your saw teeth.  In this method you want to remove all of the waste between the taped triangles that are the pins.  If you mistakenly saw into the taped triangles, the joint will be loose.

If you can consistently saw to the layout lines or the remaining taped edges, you can produce joints that will fit together with minimal or no paring...with practice.