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I am also of the camp that avoids long miter joints, but if I must do them, I use a similar approach to Handi. Only I find large panels to be somewhat awkward on the router table. These days, I'd run my router against a Festool rail. But in older, broker days, I'd carpet tape a long straight piece of scrap to the edge of the board and use it as a bearing surface for the hammering bit. Gave me very clean edges that I knew were 45s.
One other caution is that just because you have perfect 45s along the edges of large panels doesn't mean they are all going to come together at perfect 90s. Any minor bow or warp will cause a gap. It's very unforgiving unless your material is perfectly flat. MDF may help in that department, but you are still going to need to execute extremely well over a number of long joints on that project. Not impossible, just difficult.
Math is tough. Let's go shopping!
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(01-28-2020, 08:45 AM)fredhargis Wrote: Then do the field after assembly covering the edging edge. You could do the field with PSA veneer, and if you want to insure it will never seperate from the substrate apply some contact cement to the substrate first....the bond when you do this is absolutely unbelievable. I first read about this in a book on cabinet refacing.
Thanks Fred. I'm having trouble visualizing how I would do a field assembly after covering the edge, while maintaining the mitered veneer corner. Even with a PSA veneer applied to the assembled case, how could I achieve the miter in the veneer if the veneered/edged panel weren't cut at the 45* all at once? (I already have my 1/16" quarter sawn walnut veneer, it's not peel and stick)
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The more I think about this rationally the more I'm agreeing with you all.
The super tight miter of the 1/16" veneer is probably not needed visually (if even achievable)
Matter of fact, part of my wanting to add some solid wood edging even for the otherwise hidden miters, is to add some strength to the corners and allow for at least a tiny but of softening that sharp edge and help it standup to any "dings" if somebody or something hits it (it is a TV console after all.) In which case any 1/16" thick end-grain would simply disappear visually if it was even barely sanded/softened.
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I have cut long mitered joints many times without trouble, even tapered ones, using a sled on my TS. These are 48" high tapered columns, 14" at the base, 12" at the top in 3/4" MDO.
The parts are rough cut, then mounted to a sled:
Then you just run it through your TS set at 45":
For one or two parts this is likely too much work, but if you have to make a lot of identical pieces it's a great way to go about it.
John
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Interesting John, looks like a nice setup! The sled just gives things more stability rather than relying on the fence?
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(01-28-2020, 11:46 AM)mound Wrote: Interesting John, looks like a nice setup! The sled just gives things more stability rather than relying on the fence?
The sled in John's case is also preventing him from having the workpiece trapped under the blade during the cut.
It should be providing a solid reference for the cut.
MDO can be great stuff.
Don't sweat the petty things and don't pet the sweaty things. -- G. Carlin
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(01-28-2020, 11:46 AM)mound Wrote: Interesting John, looks like a nice setup! The sled just gives things more stability rather than relying on the fence?
The sled assures that every part will be cut to exactly the same size, automatically. I needed 36 identical parts and the sled made it an easy task. I was making tapered parts, but you could make the sled to cut any shape that has straight segments. The sled rides the fence; you can set the blade to any angle you want including 90°. And as Rob said, the sled keeps the offcut from being trapped.
John