Figured out how to easily veneer chamfered cabinets. Or at least I think it will work. Veneer the entire box BEFORE chamfering. When I chamfer a box, it removes about 7/8" of material from the edge of the box. When veneering, you just need to cover to about 3/4" or closer to the edge since the rest of the material closer to the edge of the box will be removed anyway. You must make sure that the veneer is bonded along the edge of the veneer really well to prevent fraying or chipping while chamfering.
Once the veneer is bonded to the surface, you can use a chamfer bit and route the edges (remember, when chamfering a box, you must chamfer all the veritcal edges first, then the horizontal edges, otherwise the corners will be at different angles, I learned this the hard way).. If all goes well, the router will trim the veneer edges flush as you chamfer the box. Now you just have to apply the veneer to the chamfered edges. You can overlap the edges a bit as well but not too much as the router will lift a bit on the overlapped edges. Then use a sufficiently long laminate trim bit (in this case, 1" since 7/8" was trimmed) to trim the chamfered veneer. Again, this should give you a clean cut. All you have to do from there is to apply veneer to the corners.
Couple of tips: I do not recommed that you use PSA veneer. The PSA is very thick and will leave a noticeable band between the veneer edges. Also, PSA tends to gum up the trim bits on the router because the glue is thick and does not really seem to dry (it actually looks like globs of thick rubber cement). If you stain light colored woods with a darker stain, the edges will become very dark and look like pinstripes on the finish. Its because the paper backing on the veneer absorbs the stain more than the veneer itself, becoming darker. Also, since you trim the veneer at 45 degrees, the area of the backingexposed is larger than veneer trimmed at 90 degrees.
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