Panel warped after glue up - need tips for round 2

So I'm building my saw till out of some red oak but think I did my clamps too tight a created a bow in the panel. It wasn't too bad on the first night but over the last couple of days it got significantly worse so I decided to start over.

https://uploads.tapatalk-cdn.com/202...1d944769bf.jpg

I've ripped it back into boards along the original glue lines and the boards are laying flat again so going to have another crack at it. Will need to rip the boards down a little further to remove the biscuits but luckily built the panel oversized so not a problem.

Any suggestions for avoiding this or setup tips for the clamps? My bench is flat and I used parallel clamps but the boards are only 15mm thick so the parallel clamps don't have a lot of mating area with the edge of the panel. I had the bars of the clamps below the panel as shown in the photo.

think I know the answer but to save embarrassing myself when proved wrong I'll defer my answer, but it has 2 parts ...thickness of timber and position of your clamps... lets see what the experts say

This is where Frontline Clamps come in handy.

Alternate your clamps top and bottom and clamp straight pieces of timber across to hold the boards flat during glue up.

Bueller, this has bitten me in the past too, where I clamped too tightly and ended up with a bowed board.

If you have jointed the boards straight, such that they form a flat gap free panel when laid together dry, you could try this technique which has served me well. Spread the glue, then rub the two pieces together to get a consistent thin layer of glue with the excess pushed out. Then clamp with just enough pressure to hold them in place. It’s really just a rub joint with the extra security of clamps.

I have used this technique successfully with stock from 18 mm down to about 5 mm.

Having said that, I am keen to see what advice the experts will offer you, and will be watching this thread expectantly.

Alternate the heart side up down up across the three . And pay attention to weather . A warm dry day after glue up will send a panel one way And a wet day after will send it the other . Specially if only one side is exposed like if it’s left lying flat in a table top . Sandwich it between two sheets of wood and it’s safe from that .

my 2 bobs worth...
with timber that thin, alternate your clamps, ie every second facing up, lay your glued timber down then drop tour other clamps in between facing down..

Quote:

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Originally Posted by auscab

Alternate the heart side up down up across the three

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This.

With timber that thin, I'd be using cauls across top & bottom to hold it flat. (Heh. Actually, I recommend cauls for any panel glue up like that, regardless of thickness. After all, although we often use 'em that way, clamps are not designed to hold it flat)

Thanks all! I'll make sure the heart is alternating and have just remembered me and dad made some panel clamps a couple of years back which are perfect for this job. Just need to remember where they are and actually use them this time [emoji23]

Will have a thread up with photos of the saw till once I have something to show, the panel was the first part I worked on so nothing else ready yet.

Maybe do it in stages, three boards at a time, don’t over tighten.