Cutting Miters by HandTimmy2Hands Jun 17, 2016
Cutting The Parts to the Exact Size
Unlike Sean's table saw method of cutting the parts oversize, I will be hand cutting them to the exact size needed, 6" and 10". I'll then be using a "Donkey's Ear" attachment for my shooting board to cut the miter. If you don't know what a donkey's ear is, follow along and you'll find out.
I've just finished cutting the grooves in the long board that will become the sides of the box.
I hit the inside face of this board with a smoothing plane before I cut the grooves and now is a good time to go over it with a card scraper to get the final finish and clean up any areas that had a little tear out from the changing grain. No sanding needed if you have a sharp card scraper and good technique.
I have not smoothed or scraped the outside face yet, this will be done once the box is put together. Right now I'm just focused on what will be the inside of the box.
So, this post is really about cutting the parts to length and cutting the miters. Well, let's get to it then.
The key to getting crisp clean cuts by hand is two things, a good back saw, and a shooting board. The first thing I need to do is take my shooting plane (in this case my #62 Low Angle Jack) to the sharpening station and hone the iron. We will be cutting a lot of end grain and the low angle in this blade will be helpful, but what really makes all the difference is being sharp, really, really sharp. I may even have to re-visit the sharpening station a couple of times throughout this process.
To help with the sawing I'll be using a couple of must have bench appliances. Bench hooks are essential in hand tool work. I use two in combination for longer boards, one has a fence and one does not. They are both the exact same thickness and can be spread out across the bench to support nearly any length of board that I'm cutting.
A shooting board is the fastest way to trim the end grain after a saw cut. There are other methods, you could just put the piece in the vise and carefully plane down to the line with a block plane, but a well made shooting board will get you to that line and keep your cut square in both direction with just a few strokes.
I start just like any other, by squaring up one end of the board. You can see just how crisp and clean that end grain is. Now I'm able to accurately measure off the length I need to cut.
So here is my set-up for cross cutting and shooting the ends. Again the two bench hooks work together to keep my work piece supported and level no matter the length. The shooting board is off to the side and will be used to clean up both the piece that is cut off and the raw end of the longer board so that I can accurately measure for the next cut.
I scribe a line with a square and a marking knife and then carry that line all the way around the board, always referencing the square to the reference face and edge.
I always make sure to keep the reference face down against the base of the bench hook and the reference edge against the fence of the hook. This will help keep everything square as I cut. I use a squeeze clamp to hold the board in place so I can focus better on my sawing technique and it's easier on my hands.
Speaking of sawing technique. Don't death grip your saw. It took me a long time to realize this, and it's really important. You need to have a very light touch on the handle of the saw, this is true with back saws and traditional rip or cross cut saws. You can't try and force the saw down through the cut faster, your saw will drift all over the place. Just concentrate on moving the saw forward and back in a straight line, if your saw is binding in the cut your not moving it in a straight line. Don't rush, it's not a race, just take long even strokes and use all of the saw plate you have. You will be surprised at just how easy it is to get straight and clean cut. Practice, practice, practice.
After each cut I clean up the end grain of the longer board as well before my next cut. You should be getting shavings off the end grain, not dust.
Alright, I've now got two long pieces and two short pieces.
Make sure they are the exact same length. If one is slightly longer that the other take a few more strokes on the shooting board until they are the same. Even if they are slightly smaller than the 10" or 6" that you were looking for, as long as they are exactly the same your box will come out square.
After shooting the ends of all those pieces I go back to the sharpening station before I start cutting the miters.
Shooting the miters with a "Donkey's Ear"
A donkey's ear is an appliance for the shooting board that holds your work piece at a 45 degree angle to sole of the shooting plane.
I made this one out of 1/4" birch plywood glued to red oak pieces that are cut into a right triangle. A hardwood fence is glued on top.
The donkey's ear is clamped to the fence of the shooting board and the work piece held against the fence and fed into the plane with each stroke.
The result is a crisp and clean 45 degree bevel cut on the end grain of the work piece. It is very easy to work down exactly to the corner because you are taking material one stroke at a time.
It is not always easy to push the plane through the end grain though. As the cut gets deeper and deeper you are cutting more and more end grain and it can be quite tiring.
So with eight of these miters to cut I tried something I've not done before.
I moved the donkey's ear to my fenced bench hook, clamped the work piece in place, and cut the bulk of the waste with my tenon saw. I kept slightly away from the line and would later move back to the shooting board to clean up the cut and bring the miter right to the corner.
It worked out really well. I had a lot less work at the shooting board with this method.
I put the parts into a band clamp to see how I did.
I've got gaps!
Maybe the band clamp is the problem, let's try Sean's method of blue tape.
Nope, still gaps! The miters are tight on the inside of the box but there gaps on the outside of the joint. The good news is they are consistent on all four corners.
My set-up was holding the pieces at an angle that was less than 45 degrees.
I took three sheets if 150 grit sand paper and shimmed the far side of the donkey's ear. I then took additional passes on each of my miter cuts until I got a full length shaving from each one.
I taped the pieces together again and the miters are now tight and square.
What a relief, I'm gonna go have a bourbon.
If you have any questions about the tools or techniques that I'm using please feel free to ask in the comments section below. I'll be more than happy to answer them the best that I can.