Replies

1. 
   DennisS | Oct 17, 2002 10:58am | #1

   The "sand" method? Could you elaborate?

   I gather you'd rather not soak the material (hot water, steam...). You can bend wood using just heat like from a hair dryer according to a few books I read recently on the subject. I've steam bent laminated pieces from, of all things, redwood with strips about 3/16" or a little less around an 8" curve. Oak is delightful to bend. A 1/4" piece should make the 2' radius curve without too much complaining. Never tried bending cherry.

   One thing to watch out for bending any wood: it should be as straight grain as you can find. Any grain runout will likely result in failure pretty easily unless you use bending straps on the outside of the curve. Please follow up on the results with the cherry. I'm interested in how it works.

   Dennis in Bellevue WA

   [email protected]

2. 
   silver77 | Oct 17, 2002 05:09pm | #2

   FW has a book "Bending Wood" but no mention of sand in there. I've bent cherry before with a simple steam box...a tough wood to bend in my opinion. Wants to break and shatter. The tip about straight grain wood is right on. Watch for small defects as well where the cherry could crack. If I had to do it again, I'd get my mould ready, put the cherry in the steamer until limp and clamp it up in the mould.

   Have fun. Be curious to know how it goes...

   silver 

3. 
   DennisS | Oct 17, 2002 06:54pm | #3

   A little further elaboration with respect to the bending strap - this is all from reading I've done without having actually used this technique:

   First principle - wood compresses much easier than it stretches. Thus if you limit the amount of stretching, which takes place on the outside of the bend, you have better chances of succeeding. But the change in length between the inside of the curve and the outside has to be accomodated. Thus you put the inside into more compression by transfering the neutral axis of the bend as far to the outside of the curve as possible.

   By making a flexible sheetmetal strap somewhat longer than your work piece and fastening stop blocks at the ends between which the work piece is held firmly, you releive the majority of the tension from the outside face and put more compression on the inside. It also helps restrain grain runout from splitting out during the bend but I'd suspect it won't do much to keep the piece from splitting once the band has been removed.

   Hope this makes sense.

   Dennis in Bellevue WA

   [email protected]

4. 
   theRev | Oct 18, 2002 02:21am | #4

   Hi,

   I am assuming (and we all know what that makes me and u) that you are not talking about bending the 1/4" edge, which is no problem at all. I would guess that there is a molding profile on the wide face, yes? If so, I would guess that it's nigh impossible to bend it that direction with only 1/4" of wood thickness.

   If you have extra molding stock, it's pretty straightforward. Although you say you don't want to rip, it would be the easiest and cleanest way to go. I think that even FH had an article on this years ago.

   Basically, you would be ripping two pieces to make one bent one. Rip your first thin piece from molding A, then compensate for the kerf loss by adding that onto the next piece ripped from molding B. If you're careful, going back and forth ripping from A and B, you should be able to get one piece which keeps your profile and is bendable.

   Scott