Friday, August 24, 2012

a simple miter jig...

In the interest of being able to make carefully controlled hand-cut miter joints for small boxes, I decided to make a simple miter jig using a 2x4 cut at 45° and reassembled on a piece of scrap plywood. This jig differs from a common miter box in that it is reliant upon only one side to guide the saw in the cut, enabling a longer saw stroke with a short fine-toothed saw. It works because a slight gap between the two parts allows the saw to make its first cut easily and along the exact angle, but as with most miter jigs, it will lose its accuracy over time. The results of the first cuts are shown in the photos above and below.
I am hoping that this simple jig will allow students to make mitered boxes.

Make, fix and create...


7 comments:

  1. Hi Doug,

    I don't remember where I saw it, but I do remember reading about early wooden miter boxes that were made with one end cut at 45 degrees to vertical. The logic was that after the initial saw cut, the end of the box could be used with a plane as a shooting board to more accurately trim the joint. I'm sure that would require some maintenance, too, but it would cut down on the need to be so concerned with the saw cut.

    Hopefully that's helpful?

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  2. JW, I know shooting boards are common to clean up miters that have gone astray. But my idea is to not let them go astray in the first place. There are two common problems in making a mitered corner box. One is for the angle to be off... The shooting board, if well made, can fix that. The other problem is that if opposite sides are not the same length, there is no way even the perfect angle can fix the box. After working with a shooting board box sides tend to vary in length due to the differing amounts of material removed to clean up the joints. So I figure it is better to be fussy about the first cuts rather than spend an excessive amount time fixing what should not have been a problem in the first place. Shooting boards and common miter boxes may work great for fitting moldings on the outside of a box, but not so hot in making the box in the first place.

    In my opinion.

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  3. Fair points, all... My rebuttal, and one more point:

    -I think 'Donkey's Ear' is probably more accurate a term than shooting board for what I described. And it can actually be used, shaving by shaving, to match opposing sides in length.

    -You're right about accuracy, and getting it right the first time. I think you'll get more accuracy with a miter box that has two sides, as the far side will constrain the blade better than the saw kerf in only one board. (My opinion)

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  4. JW,
    I don't quite understand how small parts for box sides can be successfully secured on a shooting board, and getting two sides to perfectly match in length sounds like fussy work.

    I agree that having two sides can increase the accuracy, but two sides reduce the available travel for the saw, and complicate the making of the jig and requires close alignment of parts, front and back. With the guide piece on this jig being significantly thicker than the box sides to be cut, accuracy is increased. The 2x4 does a fair job of keeping the saw at the right angle. Also remember that when I provide these to the class I'll need to have about 10 of them ready to cut. Much easier to make 10 of these than 10 more traditional miter boxes and much easier to make and provide to the class than shooting boards.

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  5. Anonymous8:29 AM

    Hi Doug,

    How do you make one of these if you don't already have a miter box - or any power tools? Is there a way to get that first 45 degree perfect without any of those things?

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  6. This jig is intended to make things easier so that less skill and attention is required. But to make one without power tools, you do need skill, careful measuring and attention. Like the miter boxes of old, the first cut must be precise, whether you are using hand tools or power tools.

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  7. It’s great. I like wood. The information good for me. I like décor my home by wood. I have problem with cutting board 45 and 90 degree. Do you sharing tips? I want to décor crib for my daughter next week

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