Clamping to correct cupping in thin boards?

Wiley,
Wood that cups is just releasing its internal pressure-what you started to do when you resawed it. No matter how hard you clamp it, or glue it, you still haven’t released the pressure. What has worked for me in the past is starting with a wider board, and ripping it into one or more pieces, see if the narrow pieces have eliminated the cup, then gluing them back together and ripping to the right width. Lots of work, but has been a solution I’ve used in the past. At the end of the day, you might be better off starting with a new piece of wood.
Gerry

-- Gerry

You probably had a humidity change, so I would think put a weight on it would probably be better than clamping it, allowing the wood to move freely to relax and lay flat. When you come back after the weekend, you should see a change and should be flat depending on what your humidity is there.

-- I don't make mistakes, I have great learning lessons, Greg

I’m not sure how to get the cup out of this particular board. For future reference though, I thickness plane a lot of my 1/4” material beforehand too. I stack these 1/4” material in stacks with several much thicker boards on top of that stack. The higher the stack of thin stock, the more weight I put on top of the stack. So far, with an axception here and there, this has kept my wood from cupping or warping.

-- http://wddsrfinewoodworks.blogspot.com/

Thy a search for a product named “Wood-Loc” Creative Woodworks and Crafts had ads for it back a few years ago, If Sheila sees this mabie she can help

Probably too much trouble for a small piece but I use an unorthodox method involving Downy and very hot water.
A lid full of downy in a gallon of boiling water poured over the wood will allow it to bend back flat, then clamp or weight it. I use this in a piece of 4” DWV to bend 1X1 oak. It’s like spaghetti after a few hours.

-- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton

Clamping or weighing down the wood for awhile may lessen the cup some at least temporarily. I don’t know if it will be flattened enough to work with. We do as William said and weigh down our thin wood and it does a great job at preventing the cupping and warping in the first place.

I mentioned it to Sheila but she doesn’t recall hearing about Wood-Loc.

-- Scroll saw patterns @ http://www.sheilalandrydesigns.com ... Pens @ http://www.finestylus.com

From what I’ve read in a year 2000 publication, Wood-Loc is a PEG like product that displaces moisture in wood.
One comment was “The unwarping of wood is pretty remarkable.”.
On another site, a fellow told of un-cupping a 3/4 board.
But, In a search, I couldn’t find any site that sold it any longer.
Posssibly, PEG might work.

-- Gene 'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton

you have to cut the cup out or start with a new piece of wood. no matter how you clamp it it will coe back, next option is to flat plane the cup out if you have a jointer. of course do this when the board is at a 1/4 inch thick then after flat planed use a thickness planer and take it down to final thickness. in other words let it stress first then machine it.