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I have a 30"x60"x2.25" thick laminated bench top that has a bow 3/32" in the center.
Is it possible to sand the bow out of it if I bring it to a local cabinet shop and run it through a Timesaver sander. I figure if it's run concave side down to flatten out the hump, then flip it to run the other side that could do it.
I want to use it for an assembly bench/outfeed table for my SuperMax. I'm building the base based on the Fine Woodworking, current issue bench.
Gary
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Sure, a timesaver could definitely flatten it. Or build a jig and use your router.
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Not a 19/38 but near the beginning he shows how to flatten a crowned, cupped or otherwise nonflat board. Your board is just a little bigger, a helping hand may prove helpful, but you can do this. Just start on the crown, and taking tiny passes off of just the top of the crown you can work it down so soon enough you will be sanding the entire face of the board. Once side A is done, flip it, and side B is a piece of cake. The shoe he uses can be a big help for support of the entire piece.
https://www.youtube.com/watch?v=m_E9sBZbD24
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GW
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Not specifically familiar with the the Timesaver, but be careful. Most wide format sanders don't flatten. They smooth umps and undulations, and they make the upside parallel from the downside. Those are not the same thing as flat.
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I wouldn't flatten this with a large sander.
I would first assemble the bench, and verify the deviation.
Then, use a router sled. Guide runners could be temporarily fixed
to the long axis of the bench and set to dead level.
It would be good to verify the supports beneath are planar, first.
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Do either of you guys saying not to use the wide sander Gary just bought actually own a wide sander? I only ask because this is by far the easiest method to do this if you do have a wide sander.
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GW
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Trying to run a slab that size through an open ended drum sander would be a real challenge. I'd use a router sled; very easy to do and you don't have to move it around. And you only have to do the show side if you first mount it to the base as was suggested.
John
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Handling the weight is the only challenge, and for that reason I suggested a pair of helping hands. The vid I posted the guy makes a sled/jig/carrier device. On Gary's board seeing that I know I would need to send it through both ways I would use a sheet of 1/2" ply cut just about to size, with a slight overage to put a small cleat at each end to keep the sander from pushing the board off the ply. I will always start crown up. Then I would use shims to get the board laying flat, and hot glue them onto the carrier so it was as flat as I could make it.
Start on just the crown first, and making real shallow passes just keep skimming the crown off. It isn't long before that side will be taking full width/length passes. At that point you are very close to dead flat. Flip the board, without the carrier to do side B. I have done the router sled deal, and that is so painfully slow it's unbearable for me, and I will try anything including hand tools to keep from that mind numbing experience. A board the size of Gary's could be complete in less than 30 minutes from starting. Your router jig wouldn't even be ready to start in that time.
Face frames, end grain boards, and big goofy pieces and panels of wood are why I bought my 19/38. It excels in all of them, and I am finding many more areas. Granted it isn't a finish surface but it is flat and making it finished is a lot less work than it used to be.
YMMV, I've said many a time here.....lot of ways to skin that cat.
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GW
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For those who doubt the ability to flatten a slab in a WB sander I can assure you with a little care in setup it is done frequently in many shops.
I have a live edge slab waiting to be set on a base that I did in my drum sander and it was out nearly 1/2" in 4' ( twisted)
It was painless to accomplish in this manner.
And having used a WB sander for many yrs in a shop I worked in we did the same thing as the OP wanted routinely
the sled and router is a fine idea if you want to do it yourself and lack the sander.
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