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Forum topic by DMC1903 posted 01-15-2014 06:53 AM 1254 views 0 times favorited 16 replies Add to Favorites Watch
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DMC1903

186 posts in 1081 days


01-15-2014 06:53 AM

Just a question for all the LJ’s, I was recently asked to construct a small pet bed that is made of 2 pc’s of bend plywood. Since bending plywood is a little foreign, I’m not sure where to start.

Our hardwood suppliers has various types of bending plywood and veneers, so getting materials is not a problem.
Any suggestions or direction’s to blogs or helpful information would be appreciated
Thanks


16 replies so far

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JAAune

986 posts in 1071 days


#1 posted 01-15-2014 07:00 AM

Always cross laminate the various layers. So don’t glue veneer on the bending ply with the grain going in the same direction. Doing so will result in a thick layer of wood that is prone to checking after the project is finished.

Expect the bending ply to soak up a lot more glue than a typical veneer glue up.

The easiest way to glue up curved parts with bending ply is with a vacuum bag but that’s not a necessity.

-- See my work at http://remmertstudios.com and http://altaredesign.com

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Loren

7831 posts in 2402 days


#2 posted 01-15-2014 07:48 AM

I don’t recommend getting into this sort of thing
unless you’re genuinely curious. It’s unlikely to
be a profitable one-off, time-wise.

You can get bending ply in 3/8” thickness and in
something like 1/8”. The 3/8” doesn’t have as
nice appearance on the edge but it is easy to
worth with.

-- http://lawoodworking.com

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DMC1903

186 posts in 1081 days


#3 posted 01-15-2014 12:54 PM

Thanks for the suggestions!

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dhazelton

1288 posts in 1051 days


#4 posted 01-15-2014 02:08 PM

Trying to make that is not going to be a win win. I’d pass.

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Earlextech

1024 posts in 1445 days


#5 posted 01-15-2014 02:28 PM

Wow! 50% of you would bail on this challenge
How do you expect to expand your abilities? Always say “Yes!”
DMC – is this a paying gig? or something for someone you won’t charge a profit from?
Either way, don’t be afraid of it. Embrace it! Do it! Expand your horizons!

-- Sam Hamory - The project is never finished until its "finished"!

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casual1carpenter

353 posts in 1230 days


#6 posted 01-15-2014 03:04 PM

Ok, I understand that wiggle board / bending plywood bends but I would question how one would lock the bend to retain the shape? The piece pictured appears to be veneered as a piece shaped over a form.

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JAAune

986 posts in 1071 days


#7 posted 01-15-2014 05:45 PM

The panel is locked into position by putting layers of veneer between the bending ply and gluing the entire sandwich together with a rigid glue while it is in the desired position. This is most often done with a vacuum bag either with the form inside the bag or outside.

Take Earlextech’s advice. You’ll lose your shirt in time and expense doing this project but afterwards, you’ll have a skill that few others possess that will sell your work and raise its value. Vacuum bagging with bending ply is easy and once you get good at building the forms you’ll be able to make money with this technique.

If you save and label your forms you can make even better profits if you can sell repeat work.

You’ll also want to use proper veneering adhesives for this job. I’ve used either Unibond 800 or Unibond 1. I prefer the Unibond 1 if I can get away with it since it’s cheaper, non-toxic and requires no mixing. It’s not as strong though and doesn’t have the longer open time.

-- See my work at http://remmertstudios.com and http://altaredesign.com

View mds2's profile

mds2

261 posts in 698 days


#8 posted 01-15-2014 06:04 PM

Bending plywood is pretty easy, and fun.

I use 1/8” bending plywood if I can get it. Basically make a form and then build up layers of 1/8” ply to the desired thickness throw, on the veneer, and then clamp it all together. I dont have a vacuum press so I make a positive and negative form out of MDF, and then just use clamps. I use TB3 for glue, without any issues.

Don’t run away from doing this project run TOWARDS it!

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GOOD LUCK TO ALL

418 posts in 482 days


#9 posted 01-15-2014 06:16 PM

I would take it in a heartbeat as long as they paid whatever it was I was asking for. Not to gouge them but you have to make a profit. Like mds2 said, it’s nothing to make a neg and pos jig to clamp the layers of ply in. I would use resin glue myself. You can get 1/8 poplar ply that will make the bends easily.

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Loren

7831 posts in 2402 days


#10 posted 01-15-2014 06:21 PM

Considering the exposed ply on the edges, I think
it will be easy to not get enough pressure where you
need it. Run some tests if you want. A 2 part form
to do that is going to be a sophisticated build since
it will probably need to be a 4-part form to get it
right and even then you may not have enough clamps
to get the pressure even enough to have clean edges.

Another (and I think more fun) way to do it is by steam
bending 2” wide boards and gluing them up to make the form.

A 2” steam bending strap rig cost about $100 from Lee
Valley Tools. I have two and gang them up to bend
4” wide parts too.

This way too, you won’t be knocking-off something
that’s been done well in a factory and gaps or voids
in the laminated curve won’t be a problem.

-- http://lawoodworking.com

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mds2

261 posts in 698 days


#11 posted 01-15-2014 06:41 PM

Another way I have bent plywood is to use one form, and then take a piece of 1/4” thick MDF and cut an 1/8” deep kerf in it, every 1/4”

This piece of MDF acts as a caul that will bend to fit your curve. Put a scrap piece of plywood on the form, then layer the bending ply, glue, and veneer. Next put another scrap piece of bending ply with no glue, and then the bendy MDF caul over the top. Then clamp it all together.

Example:

That is 6 layers of 1/8” bending ply bent to a 6” radius. The caul should be the width of the plywood being bent though.

Same method, this was the fronts of some drawers for an entertainment center.

I’m sure there are better ways, but at the time I had never bent anything before and this is the method I came up with, and it works.

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PurpLev

8476 posts in 2403 days


#12 posted 01-15-2014 06:42 PM

one of my favorite chairs (Eames) with some info:

http://veerle.duoh.com/modernhomedesign/article/creation_process_of_the_eames_lounge_chair_and_ottoman

-- ㊍ When in doubt - There is no doubt - Go the safer route.

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mds2

261 posts in 698 days


#13 posted 01-15-2014 06:54 PM

A couple more tips:

Cover your forms in packing tape or wax.
Use more than enough glue. You should have lots of squeeze out.

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dhazelton

1288 posts in 1051 days


#14 posted 01-15-2014 08:35 PM

Googled ‘bent plywood cat bed’ and saw several come up. None have the two curved pieces, just the top curved piece and some sort of normal legs. Price range is $255 – $790 (!) so if you think you can make up some forms and make more of them to sell….Of course who knows how many $790 ones sell. Or even $255 ones…

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DMC1903

186 posts in 1081 days


#15 posted 01-15-2014 09:04 PM

Wow!
Thanks for the great suggestions, this future project is for a family member, so I’m working for free.
I do not have a vacuum press, so clamping the layers in a form will be how I approach the shape.
I’m looking forward to building this, thank you for all the help

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