Bubinga Board With A Bow

[John Michaels]

I've got a piece of bubinga that is 3/4" thick about 40" long, and 10" wide. The board has a noticable bow in it and I can't plane or joint it without making the board too thin for my project. Will laying the board flat and putting weight on it correct the bow. Today I placed some weight on it, and I'm keeping my fingers crossed that this will work. Anyone here have any ideas?

[Al Killian]

Sometimes if you rip the board in half it will flaten out, but it will depend on how bad of a boe it is. Placeing bricks on it might help if it is not to bad. The only problem with trying to have the weight flatten it out it it will take a long time. Hopefully someone with more knowlegde will give you better advice.

[Mike Cutler]

John. The bow could be diminished by laying weight on top of it, bit it will most likely try to return to that position sometime in the future, thus adding stress.
I would rip the board in 2,3 or even 4 seperate boards depending on the severity of the bow, joint each seperate new board on one face and edge joint it, run it through the tablesaw for parallel, reglue it, and then plane it to thickness.

I'm certain that there are other methods that folks have.

[John Fry]

John. The bow could be diminished by laying weight on top of it, bit it will most likely try to return to that position sometime in the future, thus adding stress.
I would rip the board in 2,3 or even 4 seperate boards depending on the severity of the bow, joint each seperate new board on one face and edge joint it, run it through the tablesaw for parallel, reglue it, and then plane it to thickness.

I'm certain that there are other methods that folks have.

How does "ripping" a bowed board into three narrow boards solve the problem? Won't that just give you three narrow bowed boards?

[Steve Schoene]

Remember that you don't need to joint and plane the entire board unless you need a final piece 40" long. By cross cutting to the desired rough length for the specific parts you can joint and thickness without loosing nearly as much length.

One important point. There are minimun safe lengths that may be jointed with power jointers. But there is no minimum if you are jointing with a hand plane.

[John Michaels]

I could rip the board in half to help correct the bow, as I need pieces about 4 inches wide. The bow is moderate (about 1/8" - 1/4"). The side panels for the dresser I'm building fit into these bubinga pieces, so they need to be very straight. One idea I have is to plane down the bubinga to 3/8", then glue another piece (maple maybe) of 3/8" wood to it. That way I'll end up with a 3/4" piece that is straight. It won't matter that the board is now two different kinds of wood, because only the bubinga side will show. Does that make sense?

[Jim Becker]

John, laminating to a stable (solid wood) substrate is certainly a method for helping out with your situation, but you need to choose a secondary wood that has similar movement properties for your lamination. I'd do this in a second for panels, especially to "conserve" expensive wood like the bubinga. But for rails/stiles...I think I'd obtain straight material to mill to proper size.

[John Fry]

John,

Is this board "bowed" (a curve from one end of the board to the other), or "cupped" (a curve from one side of the board to the other)?

No matter what you are dealing with, I think it is always better to rough cut both length and width, to slightly over sized "project parts" before before milling.

[Cliff Rohrabacher]

How does "ripping" a bowed board into three narrow boards solve the problem? Won't that just give you three narrow bowed boards?

This works because you are simply face jointing the Bow away & wasting the minimal amount of lumber.

If you face joint the bow away while the board is whole you will cut off a rather large amount of stock. If on the other hand you do it to narrower strips you will be losing way less stock because the amount of curve you are cutting off is less.

Then you edge joint for square edges and re-glue thus saving the board.

[Jim Becker]

Cliff, true on a cup, but a lengthwise bow would have the same results if the board is wide or narrow. What a previous poster indicated is that ripping to width "might" cause some tension to relax and thus, require less material to be removed when face jointing it flat. I think that is a long-shot, however...and would replace the material for this application.

[Gary McKown]

How does "ripping" a bowed board into three narrow boards solve the problem? Won't that just give you three narrow bowed boards?

Do I have the terms straight (no pun intended) - "bow" = curvature along the length, while "cup" = curvature across the width? Then the only way ripping/regluing a bowed board could possibly work is to flip every other piece end for end so the bows are opposed. You also could resaw into halves, flip one piece, and reglue. I think that either of these likely will result in residual bow or a twist, which is worse.

Unless it is possible to alter the design to correct the bowed stiles or to use the bubinga as veneer, I would get a better piece of stock to work with.

[John Fry]

This works because you are simply face jointing the Bow away & wasting the minimal amount of lumber.

If you face joint the bow away while the board is whole you will cut off a rather large amount of stock. If on the other hand you do it to narrower strips you will be losing way less stock because the amount of curve you are cutting off is less.

Then you edge joint for square edges and re-glue thus saving the board.

That works for a CUP, but I don't see how that helps for a BOW.

[Mike Cutler]

Whoop's. Misfire in post #3. I screwed up and misinterpereted the OP. Somehow my 'noggin was thinkin' "cup", instead of bow. Sorry for the confusion folks. I don't know what I was thinking.:o

Okay Now that I am a little more awake. I agree with some other solutions. I would get the wood close to the final dimension ad see what I was left with. It is possible to laminate it and get what you need. Like Jim though, I would just look for a different piece of material that is straight, and true. Most of my attempts to "pull" a board into shape haven't worked out too well.

Let's not discount Cliffs post. I have seen this work both ways depending on the grain structure. I have perfectly flat boards bow coming out of a TS, and I have had somewhat bowed boards leave the bandsaw, and flatten out a bit. like Jim stated though, it's not guaranteed.

Once again,apologies for the confusion.