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Author Topic: Un-bending plywood  (Read 8359 times)

tigertiger

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Re: Un-bending plywood
« Reply #25 on: February 03, 2016, 04:56:56 AM »

...the original is laser-cut and no way I can make an accurate copy of it.
I don't have the means to saw straight - and there is the square hole there, too.
Would have to find facilities...





I cannot cut well either. But you don't need to.
Cut to within 1-2mm of the line, and then using a sanding block, sand the rest. These thin ply sheets sand really quickly.
This also works well with complex shapes, and so no need to buy a scroll saw if you don't have the spare cash, or bench space.
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Hande

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Re: Un-bending plywood
« Reply #26 on: February 03, 2016, 07:29:12 AM »


 {-)



But Finland has so much Birch that they may not like more birch wood being imported!
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Hande

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Re: Un-bending plywood
« Reply #27 on: February 03, 2016, 07:32:44 AM »


Good one!
Great advice - thank you!


I cannot cut well either. But you don't need to.
Cut to within 1-2mm of the line, and then using a sanding block, sand the rest. These thin ply sheets sand really quickly.
This also works well with complex shapes, and so no need to buy a scroll saw if you don't have the spare cash, or bench space.
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Hande

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Re: Un-bending plywood
« Reply #28 on: February 08, 2016, 12:34:08 PM »

End-of-thread:

I give up.

I soaked and heated with a hot air gun. The wood was really hot. I put the piece under pressure while bending it in the opposite direction. The plywood fell apart in places. I glued in those places, and continued pressing.

Under the pressure it didn't dry very well, but after it dried, it looked promising - for a while. - After two days, it was all screwed again (probably it wasn't all dry, after all...). It's the screwed bend that makes the situation worse. The force is enough to bend the frame, which is made of 5mm plywood.

Having the plywood brake between its layers makes me conclude that the part is lost for good.

The 5mm plywood parts of the frame were bent, too. With hot air, it was relatively easy to un-bend them. I feel good about the frame. Now going to buy a fresh sheet for the sub-deck and practice cutting from scratch. No harm there - hopefully learning something new, again.

Thank you everyone!

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JIM WORNER

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Re: Un-bending plywood
« Reply #29 on: March 24, 2016, 11:17:21 AM »

One thing I haven't seen mentioned here, would be to borrow the management's steam iron, steam the back side for about 5 minutes and then clamp to a flat surface for about 24 hours.  It works putting a curve in, so it might take one out.
Cheers  Jim W
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Unsinkable 2

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Re: Un-bending plywood
« Reply #30 on: March 25, 2016, 06:46:27 PM »

Is the piece removable? If not I'd just glue it in position and clamp it. If it is I would glue stiffness to the underside and clamp them until dry.    U2
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RAAArtyGunner

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Re: Un-bending plywood
« Reply #31 on: March 25, 2016, 11:50:24 PM »


Another trick is to seal the reverse side, anything will do, paint, polish, etc.
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