Tell me how to "pare to the line"

[Andy Pratt]

I've practiced a lot with hand cutting dovetails and I've been moving up toward accurately paring to the marked lines after sawing, but I'm not sure if I'm doing it correctly. Here are my questions:

1) Does it matter if you pare to the line on the first thing you cut (whether pins or tails) providing you mark your other pieces off that?

2) I'm currently working with 3/4 stock and my largest chisel is 3/4", so I can't pare the whole thing in one swipe most of the time, which gives some potential for a line that isn't straight, that can't be matched. Should I buy a 1" chisel for this?

3) How do you perfectly match end grain lines along the side grain. If I use a pencil it's too thick, if I use my marking knife I'm worried I'll pretty quickly start cutting into my squares (brass) and making them not-so-square. Is a saddle square a worthwhile investment?

Thanks,
Andy

[Randy Klein]

1. No, it doesn't matter, assuming your cut was square (if tails for first) or vertical (if pins first).

2. While a bigger chisel may help, practice will be a better investment.

3. Either use a marking gauge or get a square you can use with your marking knife. Having a knife line really helps in registering the chisel.

Also, are you trying to pare to the line in a single pass? Or do you take smaller bites and sneak up on it?

[Robert Rozaieski]

Andy,
Are you referring to paring the baseline or the sides of the pins/tails? If the baseline then the best advise is to scribe it with a knife and put the chisel right in the scribe line for the final paring cut.

However, it sounds from your post that you are referring to paring th sides of the pins/tails. This is a risky process. I've not had a lot of luck getting a nice tight joint by paring the sides of the pins or tails. Doing this seems to beg for gaps in the final joint. The problem with this method is that it is difficult to determine exactly where the joint is fat and then pare straight and maintain the original angle. I would recemmend trying to go straight from the saw to fitting without paring the sides of the pins and tails. It may sound like it's a difficult task but it's really not. Your first board isn't as important as you will mark the second from the first. Then saw the second and try the fitup. If it's a little tight, rather than try to figure out which pair is the offending one, plane a shaving or two off of the INSIDE of the pin board (the wider side of the pin). Then try the fit again. This ensures that your sawn angles go unchanged. I've had much better luck fitting a tight joint this way than trying to pare individual pins and tails. Almost every time I've pared the sides of pins or tails, I've ended up with gaps. If you are unsure about your ability to saw a straight line, do a few (5-10) practice cuts on a scrap board first to get the muscle memory in place before sawing the project boards.

[Andy Pratt]

Thanks guys, Robert you had it right: I'm trying to pare to the line on the sides of the pins and tails. I'm using a marking gauge already for the baseline so that hasn't been an issue. Maybe I misunderstood what people are doing when they refer to this, I thought this was the area you have to pare down to, was I mistaken?

I probably need to just start using my marking knife against the brass rule, if it wears out I'll get another one. Pencil lines there have probably been my biggest obstacle so far.

I'll try the method of planing a little off the inside of the boards to make a fit, that sounds like it's worth a shot.

I'm doing up a box right now, I'll try to remember to post pics and give a roll-up when I'm done (hopefully today).

Thanks,
Andy

[Robert Rozaieski]

No, I don't pare the sides of the pins or tails, I try to go right from the saw. I use a fine awl to mark the pins and tails, not a pencil. I think this helps a lot. Pencils don't give the saw a place to bite, an awl does so it helps guide the cut in the right place so you don't have to pare the sides of the pins or tails after sawing. I don't like using a knife to mark the pins and tails like other folks as I find they split the grain when used along the grain and especially on the end grain. This can make the knife line disappear, again, especially in the end grain. An awl scratches and in my opinion, makes a better line with the grain and in end grain. I use a knife for cross grain marking.

[David Keller NC]

Andy - A couple of comments about what you're trying to do:

1) There are at least a few ways to get a perfectly aligned mark down the face grain from the end-grain mark. In my case, I do use a pencil for this purpose, but I use a 0.5mm engineer's mechanical pencil with an HB lead. The mechanical pencil never needs sharpening, and its line width is very consistent, unlike a sharpened, traditional pencil that gets wider as the tip wears down. To get a perfectly aligned mark, place the tip of the pencil lead into the kerf left by the marking knife, slide the square against the pencil lead, and mark down to the baseline. You should, by the way, be using a small square for this job - not over 4" long. Bigger squares are harder to manuever.

2) Paring pins/tails for a perfect fit. In general, you want a tight fit right from the saw, if for no other reason than efficiency. However, very few of us always achieve that every time, particularly if both the pin and tail boards are very hard wood, and some fitting is necessary. One way to figure out which face of a pin/tail needs paring is to mark the inner edge of the tails with a soft pencil (a carpenter's pencil works well here), then attempt to fit the joint together. The graphite will transfer to the pin surfaces that are tight, and won't transfer to those that will fit. Then you just take a thin shaving off of the side of the pin that's too tight. This paring, by the way, needs to be done from the side of the pin, not the end grain. Paring down the end grain will likely make the chisel run along the grain lines, and make for a very non-square pin surface.

[Mark Singer]

very good advice so far. If you cut the tails first then pare the pins if necessary. As you saw more accurately less paring will be needed. Use the baseline to bed the chisel first by just pushing and then tapping with a mallet.