How would you solve this edge treatment challenge?

[MichaelS]

I would like to add a design element to a new desktop I'm making for work out of BB. Simply described, it's 2 sheets of 18mm BB laminated together and cut out like an L. I'll gently break the edges on the outside of the desk, but on the inside of the L (where I'll sit/stand) I'd like to add a taper from the edge in roughly 4-6" roughly 1" deep.

Bear in mind the finished L is ~ 56" x 56" on the long edges.

Short of using a 4" grinder with a shaping bit and a bucketton of sanding, or getting a specialty shaper bit, which would require some careful jigging and setup, I cannot see how to do this.

I may just use a simpler edge treatment and forgo this approach, but I'm hoping someone out there has a clever solution


Thanks in advance!

Michael

You can see something similar to what I'm looking for in this picture of a black desktop

[Guest]

How about making a trammel for a router that swings on a pivot angled down from the edge of the top?

[Cooler]

I would make the edge treatment as a solid piece of birch or maple.  I would form it from about 6" wide stock and use a half lap to glue it to the BB.   A really generous half lap should provide enough strength, especially if you cut the plywood to expose face grain.  Face grain to face grain will give a really strong joint.   Short screws from underneath will provide the "clamping" required.

The 6" wide stock can be cut while on edge on the table saw.  Something like a 7 degree angle would probably work.  And a round over bit on the very edge of the added piece.

[JGrout]

If I was doing it I believe I would make the face edgings out of solid wood, take the edging to the BS cut the bevel with a tilted table  then run it through the jointer to clean it up mostly and use a tongue and groove joint and glue to apply it to the BB ply. You will have to miter the inside corner intersection  but a spline or even a few well placed biscuits would accomplish supporting it there 

JMO

[MichaelS]

Ah - yeah - that would solve for the element.

Problem though is the rest of the aesthetics I was hoping to preserve, which was the 'look' of the exposed layers of BB. I think that either the TS or the BS method would work very well, but I'd lose that aesthetic.

Part of the problem with having the vision and then tactical engineering getting in the way
(at least in a home shop, this would not be tough w/ a cnc of course.)

Don't suppose any has a suggestion if I try and keep the exposed layering? I've seen some architectural bits where the many layers of BB are accented and finished clear to highlight the many plys. I may have to give up on the edge feature if it comes down to it though.

Thanks for the support thus far! Sorry I wasn't more explicit in the desired output though.

Michael

[JGrout]

so make the edging out of the BB  same procedure 

I am not real sure how you will like those glue lines when they widen out from the resawing but you can always test it on scrap first. 

If you go with the BB instead of the jointer I think I would make a tilted carrier for the planer bed and run it that way.

[MichaelS]

Hmmm... that's an interesting proposal - though your suggestion of trying it on a scrap first to determine whether the final aesthetic is appealing is a wise one (I can domino it back together easy enough if the aesthetic works for the edge treatment. I'll throw a washcoat of shellac on to see - but I can do that tomorrow.)

Thanks Joe!

michael

[Steve N]

If I was doing it I believe I would make the face edgings out of solid wood, take the edging to the BS cut the bevel with a tilted table  then run it through the jointer to clean it up mostly and use a tongue and groove joint and glue to apply it to the BB ply. You will have to miter the inside corner intersection  but a spline or even a few well placed biscuits would accomplish supporting it there 

JMO

^ This

Nothing says a standard edge treatment has to be just 3/4" or less out from the edge of the plywood. I've gone out 6" with a good edge bit to make a firm joint. Your look might be done with as little as 4". Think this type of routered edge, so the 2 pieces interlock well.





If the edge is expected to get a real workout you may want to reinforce from underneath. I don't think it will work if you shallow out the edge as shown, but with more meat I've seen rebar set into a grove on the bottom, and fixed with fasteners, and puttied over for a smooth feel. With having less to work with on your edge, you would need to scale down the diameter of the support, so you would likely need to increase the number of them. Dowel may work?


On your pic it appears to be painted black. With paint you can cover all manner of problem. That particular piece is likely sheet goods all the way out, and the edges dressed with filler, or thinned glue to make a smooth surface, then a few coats of paint applied. It look pretty high end, but I wonder how many years of useful life it will give?

[Steve N]

Sorry, read further and see you want to see "the aesthetic" of the edge of a piece of plywood. Just go for it, and it will be there. It will just be fanned at the front edge, nothing to help that I'm aware of. You are talking about making your own sheet of plywood out of layers of veneer to have it stacked all the way around. Could be done, but you must really like the edge of a piece of plywood to do that much work