Miters or cross bevels on long stock

[cmyk]

I generally avoid making boxes with miter joints because my results are disappointing, to me, so I make a box joint or some other alternative. But I decided I can improve my results with a jig. And that's really what I'm asking about. I came across a jig in ON HANDS Nov/Dec '84. I wondered if anyone was using that jig or some other jig to cut miters for boxes or what is described in PTWFE as cross-cut bevels on long stock. On my most recent project I used a sacrificial fence attached to my miter gauge - with sandpaper on the face of the fence and SS hold down. I didn't use a stop block, that was a mistake. Anyhow if anyone can help that'd be great. Thanks for reading.

[edflorence]

Well, without knowing just what the problem is, here are a couple of thoughts:

[*] Check the table alignment to be sure the miter gage slots are perpendicular to the arbor shaft, as per Nick's latest video. If the slots are not aligned, the miter gage face won't be holding the workpiece at 90 to the blade. It sounds like your setup with the sacrificial fence, which I assume was to back up the cut, along with the sandpaper, hold down and stop block should work if the alignment is good. The only thing I might add to that setup is maybe a clamp to press the workpiece against the face of the miter gage.
[*] Put the SS in route mode and use a 45 degree chamfer bit.
[*] If you are trying to make picture frames, try using the Miter Pro accessory.
[*] Make your cut slightly outside the line and then finish to the line with the disk sander. But, again, the table has to be aligned for this to work.

Hope some of this is helpful.

[Hobbyman2]

those can be a challenge even for the best , cutting / sanding on a knife line can help on edge crispness , there can be a lot of variables that can cause issues ,, dont give up lol , using the conical or flat disc sander you should be able to come up with a solution to trueing the miters. try using a corner block inside for strength . IMO they are not a verry strong joint unless you spline them dowel them some how or nail them JMO , the nice thing about the SS is the quill , if you clamp the piece tot he table you can just extend the quill with the disc and it should give you a near perfect edge good luck

[Hobbyman2]

Well, without knowing just what the problem is, here are a couple of thoughts:

[*] Check the table alignment to be sure the miter gage slots are perpendicular to the arbor shaft, as per Nick's latest video. If the slots are not aligned, the miter gage face won't be holding the workpiece at 90 to the blade. It sounds like your setup with the sacrificial fence, which I assume was to back up the cut, along with the sandpaper, hold down and stop block should work if the alignment is good. The only thing I might add to that setup is maybe a clamp to press the workpiece against the face of the miter gage.
[*] Put the SS in route mode and use a 45 degree chamfer bit.
[*] If you are trying to make picture frames, try using the Miter Pro accessory.
[*] Make your cut slightly outside the line and then finish to the line with the disk sander. But, again, the table has to be aligned for this to work.

Hope some of this is helpful.

---------------------

Like!!

[edflorence]

And one more thought that just struck me...you don't say how you are setting the 45 tilt on the table. There are different options here, like clinometers, combination squares or cell phone apps, but I have had good luck with drafting triangles. The bigger the better. Shopsmith sells a metal 45/90 triangle: product #521743. You might be able to find good large plastic triangles at an art supply store.

[br549]

My curiosity was piqued, so I dug out my old copy of the Hands On issue to see what it looked like. I may have to try and make one now.

sliding box making jig 2700 x 1754.jpg (420.28 KiB) Viewed 1930 times

P.S. Try as I might, I can't seem to find a good resolution for viewability and be within the size limitations. If anyone would like a higher resolution version (pdf or jpg), just send me a PM with your email address.

[larryhrockisland]

viewtopic.php?p=269031#p269031
I always have one of my miter gauges set up as a small crosscut sled using 1/4” paneling or Masonite for the bottom. Seems like this would be easier keep square than getting the fence square to the runners on the jig shown above.

[DLB]

I generally avoid making boxes with miter joints because my results are disappointing, to me, so I make a box joint or some other alternative. But I decided I can improve my results with a jig. And that's really what I'm asking about. I came across a jig in ON HANDS Nov/Dec '84. I wondered if anyone was using that jig or some other jig to cut miters for boxes or what is described in PTWFE as cross-cut bevels on long stock. On my most recent project I used a sacrificial fence attached to my miter gauge - with sandpaper on the face of the fence and SS hold down. I didn't use a stop block, that was a mistake. Anyhow if anyone can help that'd be great. Thanks for reading.

I endorse the Miter Pro, at least up to its limitations of 90 degree corners and max depth of cut. I've had one for many years and it improved my miters considerably. Which I guess points a finger at where I was having trouble. I think that up to about 6" wide I'd rough cut the pieces on the bevel and try finishing them using the Miter Pro with disc or conical sander just because I'm more confident in the Miter Pro. I haven't tried that though, so no guarantees, and it's probably not suited to everyone.

I also find the 'lock miter' router bit intriguing and would research that as an option.

That particular sled is not for me, but I could see leveraging the basic idea (which is a cross cut sled) into something I'd like. As a generalization, I prefer taking cuts all the way through past the outfeed end of the blade. This one seems to be intended for either backing out of the cut or stopping the sled and the saw.(?)

- David

[cmyk]

Someone commented that I didn't specify my problems relative to cutting the miters. So I'm hoping I can post a couple of pics, but the focus is eh. On the first pic the corner chipped out. (I used a general purpose blade...maybe I should have used a cross cut blade? Pic 2 looks terrible and Pic 3 the inside has a huge gap.

SSP 1.jpg (116.8 KiB) Viewed 1870 times

SSP 2.jpg (89.21 KiB) Viewed 1870 times

SSP 3.jpg (173.54 KiB) Viewed 1870 times

[algale]

Random thoughts on achieving perfect miters:

Miters are hard to get right and don't let anyone tell you differently.

The first rule of miters is to start with perfectly milled stock all of the exact same dimensions. That means you joint a face, then joint an adjoining edge to a perfect 90 degrees, then run the opposite face through the planer/thicknesser to get it perfectly parallel/co-planar to the first face and then plane or rip the last edge to be perfectly parallel/co-planar to the first edge. If all the stock is not prepared this way to the exact same dimensions of if there is the slightest twist, warp, lack of parallelism, the mitered corners won't come together perfectly even if the machinery used to cut the miters is set to a perfect 45 degree angle.

I mention this because in the second picture it looks like the two pieces were of slightly different thicknesses. If that's the case I don't think you'll get a good miter even if the angle is set to exactly 45 degrees.

If the work pieces are less than the maximum depth of cut, I'd be standing them up on their edge and using a miter gauge to make the 45 degree cuts rather than trying to tilt the table and cut a bevel because I find it easier to set a miter gauge than the table bevel with the degree of accuracy needed. Angle cubes, etc., are great but their resolution (one of the engineers will tell me I've used the wrong term) just isn't good enough to set and forget. Thus, whatever method you use to set the table tile or miter gauge angle, make test cuts in scrap first. If the miter is open to the inside, the angle was in excess of 45 degrees. Maybe 45.1 degrees. It doesn't take much especially since there are two pieces. If the miter is open to the outside you are under 45 degrees, perhaps 44.9.

Chip out can be prevented by having a sacrificial fence on the miter gauge (if using one) or putting a sacrificial piece of wood behind the work piece.

Getting opposite sides to the exact same length is imperative to get all 4 corners to come together even if the individual cuts are all at a perfect 45 degrees. Re-read the section in Power Tool Woodworking for Everyone on disc sanding to length. Its the best system I've found for achieving this.

Make more stock than you think you need because you will probably botch a piece and need to make another.