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View Full Version : Help! Plywood surface for painting?


zorch
03-19-2002, 09:23 PM
OK, I haven't run across anything on this topic: painting on plywood. I've got a mural project that I want to complete in my studio and then have installed at the location later. I've been giving consideration to a finish grade plywood as a base substrate because I can get it in large sheets. Anyone have any experience with this kind of board? Problems I should be aware of? Longevity? I normally work on large canvases so this is out of my range of experience and need to get some plans formulated soon. I'm welcoming any and all suggestions!

Leopoldo1
03-19-2002, 09:34 PM
Mark, sign painters use this stuff all the time. There is a sign painters grade that has a wonderful smooth surface single side to work on. You can get 4X8 4X10 sheets rather easily from lumber yards. If that grade is too fine, an A surface grade would be much cheaper and should work with some priming. When I use to be in the Crhristmas retail business, my sign painter made signs on this plywood for lots that I had. For years they were banged around, stored, unstored the next year, exposed to the weather(in the winter), etc., etc. and always looked good for the following year...........L

jimbob
03-19-2002, 09:39 PM
:cat: dear Zorch
I have used plywood that had a rough surface on one side. There is some plywood board you can buy which has a deeply ridged surface, this surface is not suitable for painting but you can fill in the deep indentations of the surface to simulate the tooth of a canvas.

lori
03-19-2002, 10:06 PM
hi zorch...

i too have painted on plywood. there aren't any problems with paint adhesion if primed correctly, which depends on your medium. what type of paint are you using for your mural?

another consideration would be for warping. i am not sure how many panels you are putting together, but it is recommended that you built a frame in the back and adhere that to the wall. if you use only the plywood and connect it to the wall, you still run the risk of it warping, and causing tension on the bolts used to hold it in place.

of course all of this is determined by size, mediums, etc.

can you give us a little more info?

good luck with the project....lori

zorch
03-19-2002, 10:29 PM
I work in oils and plan to prime the panels with five or six coats of acrylic gesso. I'd already planned on putting a coat or two of gesso on the reverse side to avoid the problem of "bowing" and to glue in a 2x2 pine frame and cross braces also. Although I'm still working out the final layouts with the client, the mural will involve three 4' x 6.5' panels.

lori
03-20-2002, 02:11 AM
mark...

sounds like you have all the bases covered. you should be fine.

post some pics when you're done, love to see it...

good luck and happy painting...

lori

p.s. welcome back to WC.

hey went to your site, love your photos, especially paris series.

what are you doing in alaska of all places???

zorch
03-20-2002, 02:29 AM
Lori,

Thanks for the compliment! Why Alaska? Mostly because I've reached a point in my career where I can live pretty much wherever I want to (with a little assistance from FedEx, AT&T and high speed internet connections!). My photography business is mostly location work, so I go where the shots are; my painting and design work is all studio work for the most part, with a little plein air stuff thrown in the mix; my workshops are pretty much all set up to be brought into my client's geographic areas...the only real monkey wrenches I've run into have been in shipping very large paintings to galleries or clients, getting art supplies in a timely manner (FedEx ain't cheap to Alaska, I can assure you) and working in a time zone that is three and four hours earlier than most of my clients on the East Coast and in the Midwest.

Thanks to everyone for the great input on plywood substrate.

antonio
03-20-2002, 10:37 AM
Originally posted by zorch
I work in oils and plan to prime the panels with five or six coats of acrylic gesso. I'd already planned on putting a coat or two of gesso on the reverse side to avoid the problem of "bowing" and to glue in a 2x2 pine frame and cross braces also. Although I'm still working out the final layouts with the client, the mural will involve three 4' x 6.5' panels.

If you are going to paint in OIL then my experience is to prime the front, back and all edges of your plywood panels with linseed OIL. The soaking in of the oil will greatly lessen any warping by the wood in the future. Oil (in the wood) and Moisture (in the air) don't mix ! Priming with acrylic gesso (which is WATER based) will introduce moisture into the wood which is the worst thing you can do. Water swells wood. Ask ANY carpenter.
After you prime with linseed oil let the wood panels air dry for a week or so and then prime with lead white in linseed oil (the best ground) or titanium in linseed (if you prefer) and your ready to go. Good luck.

Einion
03-21-2002, 05:26 PM
Zorch is longevity a consideration? If so how long do you want it to last? I would recommend either painting on primed canvas that you subsequently glue to the plywood or use hardboard instead as this appears to offer much better longevity than ply because there are no adhesives. If you must use ply choose an exterior grade of the type that sign painters use like Leo recommended, this has much stronger and longer-lasting glues than your average plywood panel.

Originally posted by antonio
If you are going to paint in OIL then my experience is to prime the front, back and all edges of your plywood panels with linseed OIL. The soaking in of the oil will greatly lessen any warping by the wood in the future. Oil (in the wood) and Moisture (in the air) don't mix !
Plywood is not timber, it is dimensionally stable and the absorption/transfer of moisture through its thickness isn't even remotely the same. Even apart from this, if you can prime 1/8" hardboard with water-based primers and not have it warp then how could there be a problem with plywood?! I don't want to revisit the merits of various priming systems since it was just hashed out at length here, but considering the lifespan of the support then longevity is not really a consideration.

Originally posted by antonio
Oil (in the wood) and Moisture (in the air) don't mix !
What about the water in the wood and oil in the primer??? With rare exceptions there is very little oil in wood (and believe me they don't use teak to make run-of-the-mill ply) while it has a moisture content of somewhere around 10-20%.

Originally posted by antonio
Priming with acrylic gesso (which is WATER based) will introduce moisture into the wood which is the worst thing you can do. Water swells wood. Ask ANY carpenter.
I don't know if you know any carpenters yourself but water-based stains and varnishes have achieved wide acceptance and use both in private and industrial circles (many pre-finished plywood products like user-installed flooring systems use water-based polyurethane varnishes). Consider the amount of water in the primer in relation to the wood's mass (and where it will go preferentially when evaporating - into the air) and you'll get the proper perspective.

Unless one is talking about soaking any wood with water then the worst that happens is a minor raising of the grain (even this does not occur all the time depending on how the wood is prepared prior to finish application) and when priming this is not an issue.

Einion

zorch
03-21-2002, 05:40 PM
I'm giving the signpainter's surface plywood a shot for this project. If I could locate any untempered hardboard in Alaska at all (let alone in the size I need), I'd probably use that instead. Tempered hardboard is available, but every single art manufacturer I've contacted has HIGHLY advised against the use of tempered hardboard as a painting substrate. I've gotten numerous recommendations for the signpainter's plywood--and, of course, I'm a bit apprehensive since I've never worked on that surface before--but it's taken the first couple of coats of gesso well and so I guess I'll see how it goes from here and just hope the whole damn painting doesn't start to slide off the surface in a year or two!

I know that traditionally, many painters worked on birchwood panels, etc. and that such panels, prepared with traditional glue ground, have far outlasted many canvas substrates. That aside, I MUCH prefer to work on stretched canvas or linen, even when the overall size is really large. Thanks to everyone for their input. If I run into any special problems with the plywood, I'll post a followup.

Anderson

antonio
03-21-2002, 07:47 PM
Originally posted by Einion

I don't know if you know any carpenters yourself but water-based stains and varnishes have achieved wide acceptance and use both in private and industrial circles (many pre-finished plywood products like user-installed flooring systems use water-based polyurethane varnishes). Consider the amount of water in the primer in relation to the wood's mass (and where it will go preferentially when evaporating - into the air) and you'll get the proper perspective.

Unless one is talking about soaking any wood with water then the worst that happens is a minor raising of the grain (even this does not occur all the time depending on how the wood is prepared prior to finish application) and when priming this is not an issue.

Einion

Several friends of mine are carpenters. This has been my experience with birch plywood. Yours perhaps is different. When I first started I primed my panels with acrylic gesso. They all warped to one degree or another. Some slightly, others moreso. However, after I started soaking the plywood panels (front,back and all edges) with warm linseed oil , several coats, letting them air dry for weeks, between coats, and then priming with lead white, I have never had a panel warp on me yet. Again, this is just my experience.
Antonio

Bendaini
03-22-2002, 03:12 PM
When i was in my teens i painted on sme scraps of plywood around the yard (parents wouldnt buy me art supplies) with acrylics and they lasted pretty well.

I should think if you get a dry enough plywood it wouldn't warp much or at all if cared for right. Ask the lumber yard about that part, their work is in wood ;)

As for treating the surface, when we did oil painting in art class in high school we sanded in between layers of paint to give it a touch of tooth for painting on... Going from a courser sandpaper to a finer one.... I dont know what kind of panals we were using though... But they were pretty large.

Also, you should think about how your going to hang it afterward. You wouldn't want nails through the front of it would you?

Bendaini
03-22-2002, 03:17 PM
Oh, ya, i just thought....

You could have adheared some canvas to a plywood surface. Someone was talking about how they did that. Then you could just paint on the canvas and if the canvas did come loose it could just be reaplyed... But there should be a way to make sure canvas did not come off of a panal.

Daniel Smith sells canvas by the yard that is up to as much as 120 inches wide... i think...

zorch
03-22-2002, 03:23 PM
There won't be any nails through the panel at all. I'm using wood glue to secure a 2 x 2 pine frame to the reverse side of the panel, along with an "X" shaped cross brace in the same material. Wood screws are counter sunk into the frame and cross brace for stability, "L" brackets are mounted to the frame and crossbraces and then attached with 1/4" screws to the reverse panel of the plywood substrate. The 1/4" screws allow the frame to become a permanent fixture on the reverse side without coming into contact with the outside two layers of the panel. I'll use the frame and crossbraces as a mechanism for mounting the painted panels to the wall in the final installation. There will also be oak carpentry along each panel edge to further assure that the panel is securely affixed to the wall.

Bendaini
03-22-2002, 03:44 PM
I think your right... that painting isnt going to go anywhere :D

Einion
03-23-2002, 01:07 PM
Fair enough Antonio, although I'm curious as to what size of board you're using and the thickness.

Einion

antonio
03-23-2002, 06:12 PM
Originally posted by Einion
Fair enough Antonio, although I'm curious as to what size of board you're using and the thickness.

Einion

Birch Plywood 3/4 inch thick - 5 ply

comes in sheets 4 feet X 8 feet
122 cm X 244 cm if my math is correct

largest panel i've done is 77 X 48 inches
195 cm X 122 cm ?

usually i prime a large quantity of boards of various sizes at one time. i do it indoors during the winter months when it hasn't rained or snowed in over a week so that the humidity level is very low and combined with the heat in the workshop the moisture level in the wood is at the lowest possible point. the panels are then receptive to absorbing more warm linseed oil i believe. i let them air dry for at least a week and, when atmospheric conditions permit, repeat the process several times. Finally, i let the panels dry completely over the following months and then prime them with lead white in linseed oil, usually two or three thin coats, allowing each to dry a week or so between coats. By doing many panels at once, i always have one ready at all times.
Antonio