Thicknessing Stock for Arched Moulding Production
Advice on achieving thickness tolerances in thin rips for gluing up arched moulding blanks. October 19, 2013
Question
We're progressing very well with arched moldings. They look nice and stain up well with barely a glue line. Problem is: It takes too long to make the glue strips. We first rip them on the SLR, but make them oversized to account for the variability in thickness.
We then plane one side only on the small Dewalt planer. This is what is taking too long, planing down 4 or 5 times to get a consistent thickness. How or what process are you using to work up your strips, getting them ready for the arch glue up clamps?
We've tried it on the table saw, but the starting/stopping of the board as you reposition your hands causes kerf and saw marks that will take more to plane out.
Forum Responses
(Solid Wood Machining Forum)
From contributor A:
Power-fed resaw and overhead sander. Two head sander with coarse on first head. One pass each side.
From contributor S:
We do it the exact same way, only we run them through an SCMI planer 1 time. We have a digital gauge on the planer with a chart for each final width.
From contributor J:
Sounds like the problem is running multiple passes for a consistent thickness. Either rip the strips narrower, or upgrade to a planer that can do it in a single pass.
From contributor M:
Get a good blade for the tablesaw. Learn how to use the tablesaw. The parts coming off of the table saw should be the same size. They just have minor defects that should be taken off in one pass per side in the planer or sander.
From contributor I:
You could order your bending strips from a mill. They'll be gang-ripped and drum sanded. (Two men working the machines can easily produce box cars full of strips.) You can then thickness plane two or three pieces to yield exact bundle widths.
If you're match laminating your stock, you'll probably want to set up your own power-fed, gang-rip and drum sanding operation. With the proper saw blades and feed rate, you might even be able to dispense with the sanding operation.
I believe a Woodmaster planer/molder can be set up to gang rip.
From contributor P:
When I was working in a custom shop and we produced roundtop casing, we would purchase the wood (veneer) in 1/8" thickness and 6" wide, in pine. It would all be the same thickness and bend nice on the machines. When it was glued up, the veneers were not real noticeable. If it was to be stain grade we would pick the veneers to match as close as we could. These moldings were made for one of the top 3 window companies, distributor. The company was Idaho Wood Veneer.
