Hello, it’s been a while since I posted last (sounds like a confession) anyway here’s my question:
I am building a sculpture with a wooden framework covered with canvass. I have stretched the canvass as best I could and stapled it to the framework. Originally I was going to prime and varnish the canvass, but thought maybe it needs more rigidity and toughness (the sculpture will be outside–in Michigan). I thought of diluting yellow carpenters’ glue and brushing a good, soaking coat of glue on the canvass. Was thinking that it would sort of bind the overlapping pieces together so the thing acts more like one skin, and the glue will add rigidity to the canvass.
I know that this kind of glue (is this what is also called resorcinal glue?) is not waterproof, but planned on priming the glue-sized canvass with something like Zinzer 1-2-3 and then painting with oil-based “spar” varnish (the kind with UV protection). Ultimately, I do want the final coat to be varnish because I found that it looks spectacular over gold spray paint when you mix transparent artists’ oil paint in with the varnish–gives the surface a “candy apple” look.
(Someone at Breaktime said that oil-based exterior enamel that is a “number 4 (neutral) tintable base” is in fact transparent and to use it instead of varnish because it has better UV inhibitors, but I don’t know–guy in paint store said it is not transparent and I’d be better off painting the sculpture with latex house paint. I don’t want that look though.)
Do you see any problems with the glue “size? Will the varnish overcoat protect it enough?
Replies
If you want to get the canvas tight, pour hot water on it and it will shrink to be far tighter than you could ever get it by hand.
For a finish, try googling for "fabric aircraft".
Hay Danno,
Were you the one making an outdoor dragon?
Any how, Your right in that you need a "sizer" for your canvas. Shrinking or gluing will only temporarily shrink the canvas.
Periodic fluctuations in humidity will vary the tightness
considerably.
This being exterior you probably want to avoid Rabbit skin glue
( you'd need to use linen not canvas anyway). So I'd say a call
over to Golden paints is in order. They have several acrylic
grounds that are transparent. They can direct you from there better
then any one so I'll leave it here.
How about rethinking the idea of canvas for the panel. Something like sheet aluminum (or copper, depending on size and budget) bent over your framework would likely last much longer.
Back with the fabric. Make sure you are using monel or stainless staples or you will see rust stains quite quickly.
What you are suggesting is similar to how we make muslin-covered "flats" in the performing arts. Flats usually become walls of the set (though they can be made for many types of scenery). Here is how you make a flat; you'll see it's similar to your method.
In flat construction, you build the frame out of 1x3 or 1x4 pine. Then glue muslin to the face of the frame and staple the inside edge. You actually leave the muslin fairly loose. Then, once the glue is dry you coat the whole thing with sizing. A watered down white or yellow glue works fine. Once the sizing is dry you check it for tautness (the muslin will sound like a drum when you tap on it). If you missed some spots, paint some more size on. Once it's sized, you give it a base coat of paint, usually latex.
Although you could shrink the canvas with simple hot water, the canvas will sag when it gets wet again (either humidity or your first coat of paint). A sizing keeps it from doing that.
Hope this helps.
Thanks for the ideas and suggestions. Yup, it's me, the dragon maker from Breaktime.
I helped a guy move a washer and dryer the other day and when he asked what I'd been up to, I said, "Making a dragon," and he was sort of at a loss for words.
I've noticed already that staples I made from iron wire (it's a long story) have already rusted. I made a framework of 1/4" oak plywood glued to a core of Styrofoam. There is a central sort of keel and two cross "bulkheads". Then I added bulkheads out of just Styrofoam to give it more three dimensional look and to infill. Then I glued and "stapled" sill seal (some sort of flexible polystyrene or something foam) as well as some plastic mesh. Then I stretched artists' canvas in overlapping strips. That's as far as I've gotten when I began wondering if the thing would end up stiff enough and taught enough. Like I say, I was going to just prime the canvas with water-based primer and then varnish. Thought glue would make a harder, tougher finish under the varnish.
I've got to transport it to the site (it's five feet tall, four feet long and wingspan is three feet) and fasten it to a concrete base they are providing. Wanted it to stand up to the transport process!
Have also thought about "punting" (abandoning the varnish idea, which I really like because it worked so well on a wood sculpture I did two years ago--people really liked the look of the "candy apple red" over metalic gold--very rich looking, like bronze) and just putting epoxy on the fabric once it's sized. Not sure how I can do epoxy in clear transparent colors though--and it's a PITA to work with!
In meantime I'm fighting flu, which is why I'm up typing at 1 a.m. instead of sleeeping!
I didn't think of this till just now, but you being in theater could probably give some good ideas to a question at Breaktime about portable plywood boxes for dance platforms: http://forums.taunton.com/tp-breaktime/messages?msg=103151.5
I did my best, but....
Varnish isn't for exterior. I think there's other ways you could create the look. The idea of stretched aircraft canvas sounds pretty good. I think you need to to look in other sources than a WW forum.
Danno, the large model air craft folks use a light glass cloth and resin coatings to cover 1/4 scale planes, just like the fabric and dope in 1918-WW I .
Check for suppliers with the A.M.A. - The Academy of Model Aeronautics,Muncie In. at 765-287-1256
You arelooking to hook up with some of these.
fiberglass cloth from Composit Structure Technology co.
resin from Pacer technology co or Klass Kote below.
********************
or using heat shrink iron on fabric try-
Super Coverite fabrics painted with
Klass Kote epoxy paint from Deversified Products 1-612-866-1212 ask for Nate Dickerson and explain your project . Paddy
Thanks for all the info and numbers. Will check it out. Was too sick today to even think about it, slept all day.
Many years ago I made a kayak with a stretched canvas skin over a wooden frame. After the canvas was stretched and tacked in it was as tight as I could get but by no means perfect. I applied "airplane dope" to it which tightened it up very well; when that was dry several coats of marine paint were applied (I think it was a poly type). I believe that this was the construction of early airplanes. It was seaworthy for a good 25 years with just a rare paint touchup -- it may be seaworthy still! I had no problems with paint cracking. I would look in kayak building forums to see if this is still done.
Thanbks. That's what some at Breaktime suggested and I looked into those a bit. I don't know what aiplane "dope" is--is it still available?
The main thing is I really liked the look of the varnish I used before and was thinking if I provided a fairly stable substrate, it wouldn't crack. I will do some samples and see what happens. The bulletproof way would probably be epoxy or similar resin, but don't know of any that are transparent.
Aircraft dope is just a high-flexibility lacquer. The original formulation was basically nitrocellulose lacquer, with some additives to enhance flexibility. I believe that polyurethanes have largely supplanted aircraft dope, in part because aircraft dope greatly enhances the flammability of whatever it is applied to. ;-)
-Steve
Thanks--I was thinking nitrocellulose and remembered that as being flamable. I'm experimenting with things right now. Trying Tightbond II as size, alone or mixed with PVA primer--seems to shrink the fabric, but so far hasn't made it much stronger. I have found that cotton T-shirts work better than the artists' canvas I bought for getting around curves and so on. Guess I can use the canvas on stretchers for its original intent!
Hey Danno,
Did you ever talk to Golden?
You seem to be struggling with the same issues.
The only reason I keep bringing it up is, I met one
of their chemists at a party.
We got to talking and he described a medium that seems like it
would work for you.
How did he describe it?
Something like- What would you say to a sizer that is also a ground,
that goes on white (so you can see what your doing) but dries clear.
And when done is quite rigid.
I haven't used it myself, but that is basically what he claimed.
What your trying to do is tricky if it's going to be Archival.
I say talk to the pros.
PS
Lets see some pics of the dragon.
I thought about various mediums and gessos and even modeling paste (which I came very close to getting, but it was very expensive--one was lightweight and dried hard and could be had in different shades from white to black IIRC). I was concerned that most art work is not outside. The modeling paste seemed to sound like it would be okay for outside. Anyway, I am happy with the glue sizing and PVA primer I'm using now and I don't really want to rethink everything at this stage or I'll never finish.
I suppose I should have done like one of the artists did last year when she made a bench that looked like a box of chocolates and use epoxy over Styrofoam. She is doing the same this year with her dragon.
There are some major constraints to the design that not even the sponsors are really aware of--one is that the sculptures though somewhat large (max 5' tall, by 4' long, by 3' wide) must be able to be moved by "one or two men". Yet, it has to be not able to be moved once in place--they provide a concrete slab base with a vertical steel sleeve that a 2x4 integral to the sculpture slides into. It must be able to withstand Michigan weather--which includes rain and snow and hot sun as well as strong winds. We are having winds with gusts around 40 mph today for example. So, although my sculpture will have wings, I am making the "feathers" out of Nylon fabric panels attached only at one end of wing struts (like bones). When the wind isn't blowing, my hope is that they will lie down and look like a wing at rest and when the wind is blowing, will flap outward like flags.
As I have said, the block sculpture I did two years ago was well received, and was bought by Dow, Howell, Gilmore (archtects--the founder of the co. was Alden B. Dow and it was in his memory that the sculptures were "commissioned" by the DDA) (they paid the highest price of any single sculpture--a pair called "Alden Man" and "Alden Woman" by Jim Ardiss sold for more) and is on display on the campus of Nothwood University. Anyway, what was especially good about that one was the finish, so I want to try that again.
I will try to post pictures--it is a complicated process with my computer vs. AOL--I must download to myself as email, then upload to Prospero or it will not work--I've tried and tried other ways, but that is all that works. You could also email me your email address and I can send pictures directly to you and it would be a lot easier!
I sent you my info,but I'm
not sure if I did it right.
You did, I got it and three pics in separate emails are winging their way to you as we speak.
Rosco, a theatrical supply company, has a number of coatings for odd applications. Maybe see if you have a distributor near you. http://www.rosco.com
Thanks for the link--looks interesting--could have used the "Foamcoat" to cover the Styrofoam I used, but now it is covered with cloth and glue, so that's done. Phosphorescent paints sounded interesting, may find out more about them. I put some yellow glow-in-the-dark paint on the Dow Block sculpture, but it didn't show up. I am already putting glow-in-dark eyes in the dragon--don't want to overdo it!
Build it on a Copper sheet!
My stipend was only $500! Have to start raiding Lowes and stealing copper from old roofs and wash tubs!
Go for it! I'll tell the Cops you went in a different direction!
Yeah, I'm sure they'd understand--especially if I showed them my artistic license! Unlike James Bond's, it doesn't allow me to kill, only to steal.
Pennies !
My local elementary school had some fund raiser
where they collected pennies and spread them over the
gym floor. It looked amazing.
There you go! But hardly light weight! I was thinking about sprinkling glitter or sequins onto the wet varnish and varnishing over them. So many ideas, so little time!
I'm sure it's against some law too.
This forum post is now archived. Commenting has been disabled