Wood bases. How do you kep them from warping?

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Wood bases. How do you kep them from warping?

Steve Kubik
Steve Kubik

August 7th, 2004, 8:49 pm #1

Hi guys,

I'm curious how you all keep the wood bases from warping? I use Sculpt-a-mold as the groundwork. I've used red oak and poplar wood as the base, sealed with spar urethane(Four coats) before applying the wet groundwork. Still, the wood base develops a warp after just a few days.

The only wood that hasn't warped was birch plywood. It doesn't look bad sanded and stained, but I'd rather use a nicer hardwood.

Any ideas?

Steve
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Rick Purdy
Rick Purdy

August 8th, 2004, 4:35 am #2

Hi Steve!
OK,the red oak can warp on it's own if you seal it soon after it's last shaping/machining.There is inherent moisture and grain stress that gets relieved(by warping) after major machining steps such as cutting to size,shaping,and edge profiling.Maple is another warper in this regard as is all hardwoods to some extent.Poplar should be less so,but more on that in a little while.
The hardwoods should be cut and machined to roughly 1/8"(3mm)of final dimension.Let it rest on a shelf for 2-3 days.It will have some warp when you go back to it.Machine/shapeit down to final size and let it rest another day.Should be OK. Sand and seal THE WHOLE PIECE,not just edges and one side.This may be where poplar warped out on you.If seal is un-even,then moisture 'travel' is un-even,therefor,warp.A lot of wood suppliers harp on 'kiln dried' and 'seasoned' stocks.The truth is that the moisture content returns to close of original soon after the stock leaves the kiln.Nothing anyone can do about it,just is.
Softwoods,such as pine,are not likely to warp like hardwoods,so bang away and then stain to an oak shade and seal.
Hope this helps,
Rick
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James Higgins
James Higgins

August 8th, 2004, 7:50 am #3

Hi guys,

I'm curious how you all keep the wood bases from warping? I use Sculpt-a-mold as the groundwork. I've used red oak and poplar wood as the base, sealed with spar urethane(Four coats) before applying the wet groundwork. Still, the wood base develops a warp after just a few days.

The only wood that hasn't warped was birch plywood. It doesn't look bad sanded and stained, but I'd rather use a nicer hardwood.

Any ideas?

Steve
n/t
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Robert Lockie
Robert Lockie

August 9th, 2004, 11:44 am #4

Hi guys,

I'm curious how you all keep the wood bases from warping? I use Sculpt-a-mold as the groundwork. I've used red oak and poplar wood as the base, sealed with spar urethane(Four coats) before applying the wet groundwork. Still, the wood base develops a warp after just a few days.

The only wood that hasn't warped was birch plywood. It doesn't look bad sanded and stained, but I'd rather use a nicer hardwood.

Any ideas?

Steve
Mr Zaloga builds his groundwork on a sheet of Plexiglas, which being impervious, is not prone to warping. It can then be bonded to a wood base and there is no risk of the groundwork warping the wood.
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Barry Gazso
Barry Gazso

August 10th, 2004, 4:36 pm #5

Hi guys,

I'm curious how you all keep the wood bases from warping? I use Sculpt-a-mold as the groundwork. I've used red oak and poplar wood as the base, sealed with spar urethane(Four coats) before applying the wet groundwork. Still, the wood base develops a warp after just a few days.

The only wood that hasn't warped was birch plywood. It doesn't look bad sanded and stained, but I'd rather use a nicer hardwood.

Any ideas?

Steve
Hi Steve,

I feel your pain. I've begun to simply screw a slightly smaller piece of 1/4" plywood to the bottom of the plaque. It keeps the plaque from warping and as a side benefit provides a slight reveal I use to pick-up the finished piece. I just paint the plywood flat black.

Regards,
Barry
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Steve Kubik
Steve Kubik

August 13th, 2004, 1:47 am #6

n/t
By chipboard, do you mean pressboard? Do you seal it with anything first?

Steve
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James Higgins
James Higgins

August 16th, 2004, 1:00 am #7

... is a board made from thousands of tiny splinters of wood all pressed together with glue, so I presume pressboard is another name for the same thing. What I did was cut out the right size and give it a coat of Estapol varnish. This seals it and it didn't even warp a tiny bit. Great actually. I tapped small nails into the base, leaving only a few mm's out to help bond down the plaster. Worked fine.
Cheers,
James
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Rob Plas
Rob Plas

August 24th, 2004, 7:05 am #8

Hi guys,

I'm curious how you all keep the wood bases from warping? I use Sculpt-a-mold as the groundwork. I've used red oak and poplar wood as the base, sealed with spar urethane(Four coats) before applying the wet groundwork. Still, the wood base develops a warp after just a few days.

The only wood that hasn't warped was birch plywood. It doesn't look bad sanded and stained, but I'd rather use a nicer hardwood.

Any ideas?

Steve
Cheap, easy and always works well.
ROb

http://missing-lynx.com/articles/dio/di ... bplas.html
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Joined: September 20th, 2003, 3:28 pm

September 1st, 2004, 3:00 pm #9

I do my actual model base on 3/8" all weather plywood. The plywood has been prefitted into a front mounted plain wood or black frame. So if the base warps at all you'll never see it once mounted in the frame. I will then extend the groundwork out to the edge of the base where it meets the frame edge. See my Russian Tank riders dio in the gallery for an example of this kind of mounting. For my last several pieces (god i don't build enough or very fast) I've started to use much taller 2-3" and I use a smallish base so the vehicle takes on a more "dynamic" stance-that's how my FSM sherman and Tiger are mounted.
My2cBobC ps it also helps that my model club has a master woodworker as a member and he makes whatever base/frame is requested from scrapends in wonderful woods like walnut-cherry etc etc and for almost nothing-I guess that would be considered "falling in it and coming out smelling like a rose"
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