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bottleman
10-12-2000, 03:35 PM
Has anyone tried PVA size? It's being marketed as a replacement for rabbit skin glue. To be honest, I've never tried hide glues either. Just curious.

sgtaylor
10-12-2000, 05:08 PM
I have never used PVA size, but will probably be trying it sometime in the near future, and will be glad to report back.

From what I understand, some conservators are recommending PVA size over rabbit skin glue when painting on canvas or linen. Apparently, the hide glue size is held responsable for cracking in works done on fabric. As far as I know, rabbit skin glue is still the prefered size when working on wooden panels.

In another thread ("Does anyone do oil priming...") windex claimed to be unhappy with PVA size, as it did not shrink and tighten the canvas the way that hide glue does. As I've said, I haven't tried it yet, so I really can't say.

You might want to take a look at that thread.

Anybody else? I am as curious about this one as bottleman is.

rhoward
10-12-2000, 07:26 PM
Conservators are using PVA on old leather, buckskin clothing, fabric and other non-art subjects. It's just carpenter's glue.

windex
10-12-2000, 07:39 PM
I use PVA size all the time. I don't love it (as noted above), but it'll do until I find what I really want. Conservators apparently it will be less troublesome in 200 years or so. Personally, I am somewhat less concerned with what my work is gonna look like when my hypothetical grandchildren are dead than I am with my experience in making a canvas <u>now</u>.

Rabbit skin glue does 2 (two) things: 1) It protects the canvas/linen from the oil, which will eventually eat away at the canvas/linen if there isn't some kind of barrier bedtween the two. 2) It tightens the canvas (I think that this property is called "hydroponic", but whadda I know). PVA size does 1), but not 2). I use primer, but if you're into rough texture, you can even paint directly on PVA size (which dries pretty close to clear) and let the canvas/linen show through. If you are using acrylic primer, you don't need PVA size at all.

Unsurprisingly, Gamblin is pushing PVA size, but hard. There's a link on their web site to a Canadian conservation web site where you can read a whole lot about PVA size. I read several articles posted and linked to that site, they convinced me that it was a good idea conservation-wise, and preferable to rabbit skin glue. I then promptly expunged my memory banks of all the pertinent background info, remembering only the necessary conclusion: Use this stuff when priming is needed.

That said, I am still seeking the holy grail of a synthetic size that has the same tightening properties that rabbit skin glue has.

arcitect
10-12-2000, 08:01 PM
Originally posted by windex:

Rabbit skin glue does 2 (two) things: 1) It protects the canvas/linen from the oil, which will eventually eat away at the canvas/linen if there isn't some kind of barrier bedtween the two. 2) It tightens the canvas (I think that this property is called "hydroponic", but whadda I know). PVA size does 1), but not 2).

Hot water will get you your 2.

rhoward
10-13-2000, 09:46 AM
If all you are looking for is a glue...any glue will do. The reason that many skilled painters (and skilled furniture makers) prefer hide glues has to do with other qualities besides its ability to adhere something to something else. There are some excellent fillers and adhesives that hold the wings on jet planes and expanding polyesters do a marvelous job of filling even microscopic scratches. Those synthetics will doubtless last for centuries. So why don't artists use them? Because they don't handle well.

Hide glues do something synthetics do not do. They go through an intermediate gelling stage which has many advantages. If you are attempting to adhere canvas or paper to another substrate, you will need to hpress the surfaces together and hold them until the glue dries because the inevitable shifting will cause air pockets. Hide glues have the ability to hold one surcae against the other (furniture makers call it "suck," when two surface are rubbed together until they suck together. That holds the joint tight until the glue evaporates).

Well-made hide glues do not deteriorate for several reasons. The best ones are clean, made with fresh hides and don't stink from decomposed skin (if your glue has an unpleasant smell, it's junk). Clean glue is less likely to bring its own pathogens. The best hide glues also have a microscopic amount of fungicistat and bacteriostat added.

What's this all mean to someone sizing a canvas? The best way is to keep the full strength glue from fully penetrating the linen and going only part way through. This is done by first diluting the standard glue solution (11:1) in half (22:1) and "giving the canvas a drink." This light dilution still allows the canvas to flex. Raised fibres are either trimmed or burned off (never sand the canvas). Once that's dry and hard, the full strength glue solution is applied with a brush and, as it begins to gel, the gel is smooth with the palm of the hand. The resulting surface maintains the quality of the linen and provides a congenial surface much better than any of the synthetics can.

I've tried them all and have come back to using good bunny glue.

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AIGottlieb
10-13-2000, 02:28 PM
Originally posted by rhoward:

The best ones are clean, made with fresh hides and don't stink from decomposed skin (if your glue has an unpleasant smell, it's junk).


Well, that's just freakin' great. That means that EVERY SINGLE rabbit skin glue I have ever used is garbage. So who's selling the good stuff?

bri
10-13-2000, 03:06 PM
AIGottlieb,

Actually, Studio Products is selling the good stuff, not that the rabbitskin glue that i used to use from Fredrix was bad--it smelled good too, but there is a notable difference in the scent from Studio Products. It is pretty darn gluey, too! They also sell hide glue. I have only ever used the Fredrix and Studio Products brands. I have never used the sheets.

-----bri

rhoward
10-13-2000, 04:02 PM
Originally posted by AIGottlieb:
Well, that's just freakin' great. That means that EVERY SINGLE rabbit skin glue I have ever used is garbage. So who's selling the good stuff?



*chuckle* I know that it sounds dire, but don't despair. The sheets of glue from France are excellent -- well made from fresh bunnies. The Claro grade that we handle is very similar except that we sell it as granules rather than in sheets. Both make up into a pale straw colored gel that does not have that dead grey quality one sees on rotted meat and the glues made from rotted hides.

There will always be those people who will use inferior materials and foist them off o the public. Just like you, Adrian, we felt frustrated having a chice of that smelly grey goop nd those expensive French sheets. Then a friend came back from Portugal with a Portugese wife and a bunch of bunny glue (smells like glue, not road kill). We made contact with the glue makers (through his wife) and we've been importing it for several years. It's really super stuff. We also get out 376 gram hide glue and technical gelatin from the same source. They are very honorable people to deal with and we have had nothing buy raves about the glues.



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AIGottlieb
10-14-2000, 05:02 AM
Excellent. When I get some money, you'll be the first to know.

rhoward
10-14-2000, 11:04 AM
Originally posted by AIGottlieb:
Excellent. When I get some money, you'll be the first to know.

It's cheap...about $15 for a pound. That'll make a couple of gallons of glue. Stuff like BEVA 371, PVDC and some high quality PVA goes for over $100 per gallon. You don't need a Nobel Prize in economics to figure out the cost/benefit ratio.

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[This message has been edited by rhoward (edited October 14, 2000).]

arcitect
10-15-2000, 04:00 AM
Tech heads rock. They are awesome people who tend to love what they do.

PVA works real well. Rabbit skin glue sucks if you need a 1000 year life span -lol!

Real deal -a half-assd rabbit skin glue job will fail right quick. A good job will last for centuries!

PVA is real good -theoreticaly. Note, it is JUST as size. No more, no less.

Rabbit skin glue is probably horribly old fashioned, but even still if you do it right -it will last centuries!

PVA is probably a better bet -but hide glue works as a size -be it rabbit, horse, or dog. Which it may very well be.

rhoward
10-15-2000, 09:21 AM
Originally posted by arcitect:
hide glue works as a size -be it rabbit, horse, or dog. Which it may very well be.

That's true in the case of the badly made glues. I know of three sources for real rabbitskin glue made from real bunny skin. All are connected with felt factories that make felt for the hat industry. The fur is shaved off and sent to the felt factory and the skins are made into glue. I know that the hide glue and the technical gelatin we carry are made from a variety of hides...mostly cattle. Kodak has a gelatin factory close by and they are VERY fussy about the quality of the bones they use, paying three times as much as does the Jell-O factory.

There are stil some places that make quality products.



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arcitect
10-20-2000, 06:14 AM
Originally posted by rhoward:

There are stil some places that make quality products.


You are absolutely correct. We can not argue this. There are many of us who STILL care!

Allt that aside, a good PVA (which is white glue for those who do not know) is STILL a good bet.

Rabbit skin glue IS REALLY REALLY good -but rarely made of rabbit these days.

It is all a matter of understanding covalent bonds. An oil film WILL form a covalent bond with hide glue. It will also form said bond on PVA (but not as strongly).

Either way -you are AOK!


and P.S. Many of us really do STILL care!!!!!

lori
10-20-2000, 08:07 AM
i just want to go back up the chain a bit here and ask rhoward why not sanding? i do exactly the process he suggests (i think its pretty common), but i sand my canvas in between the thinned coat and the "pure"
rabbitskin coat. why burn, instead of sanding. i have to add that i like what sanding does...as is with all my techniques, i use them because i like the results. however, if i'm compromising the process by doing something wrong, i'd like to know.

rhoward
10-20-2000, 06:00 PM
Originally posted by lori:
i just want to go back up the chain a bit here and ask rhoward why not sanding?

Sanding will break down the threads and weaken the linen whereas shaving or burning just gets the fibres standing proud of the surface. I'm going to experiment with using a little BIC disposable razor to see if that will work.



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LarrySeiler
12-16-2000, 10:54 AM
What about the recent hullabaloo that conservators are discovering that a particular bacteria is having a hay day feeding on the protein content of rabbit skin glue on some of the existing older works? Hogwash??? Ideas why??? Nothing to be concerned with?

Larry

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"Art attacks can skill!"

rhoward
12-16-2000, 01:34 PM
Originally posted by lseiler:
What about the recent hullabaloo that conservators are discovering that a particular bacteria is having a hay day feeding on the protein content of rabbit skin glue on some of the existing older works? Hogwash???


It must be remembered that conservators are not any more related to painters and understanding of the problems of making a picture than are framers and the guys who sweep out the museums. Have you ever seen the attempts at painting by those "experts?" The last time I got such disconnected and unrealistic advice was when my parish priest was lecturing me about sex.


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rhoward
12-16-2000, 01:37 PM
Originally posted by windex:
I am still hoping to find a synthetic substitute for bunny skin



The Eveready Bunny looks like a good synthetic bunny. http://www.wetcanvas.com/ubb/biggrin.gif


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Mich451
12-16-2000, 02:27 PM
Just a sidetrack on the sanding...I don't sand or burn. I have gotten great results shaving the canvas first with the tool that de-pills and defuzzes sweaters and then reshaving with an electric razor. I do this before before I do anything else to the canvas and then again after the first light sizing.

rhoward
12-16-2000, 09:27 PM
Originally posted by Mich451:
reshaving with an electric razor.

Great idea. I'll try it.



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windex
12-17-2000, 12:25 AM
Originally posted by Dru:
I notice that there seems to be a concern about PVA (or any acrylic sizing) not tightening the canvas as well as skin glue. When stretching canvas that's going to be glue sized, one doesn't stretch it to drum tightness because the glue (and/or the pre-wetting) will tighten it. When planning to use an acrylic size, pull really tight when stretching and this particular issue, at least will be resolved.


I gotta tell you, this sounds fine in theory, but I've tested it (same linen, same kind of stretchers, same canvas pliers, and the same hands putting it all together) and I'll tell ya, pulling it really tight is no substitute for bunny skin glue. It just doesn't get as tight. Really.

Pouring boiling water on the linen helps get it tighter (someone in this thread suggested that, too) but I had a bad experience in one instance where this caused lightweight stretchers to warp.

Thus far, the best non-bunny alternative seems to be heavyweight stretchers plus boiling water plus PVA. I am still hoping to find a synthetic substitute for bunny skin, though. Heavyweight stretchers are expensive, and I do many small canvases where I don't really need 'em, except for that boiling water step.

bk7251
12-17-2000, 01:43 PM
-but hide glue works as a size -be it rabbit, horse, or dog. Which it may very well be.[/B]

You can make glue from dogs? I have a very elderly golden retriever. Hmmm . . .


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Barry Katz

LdyBiss
12-18-2000, 04:56 PM
Originally posted by arcitect: dog...


(( Looks at her dogs and cringes ))

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"You want the ecstacy so you have to take the hangover"
Hesse

LdyBiss
aka
Sandra. M. Smith

donjusko
12-19-2000, 05:10 AM
PVA all the way! Vinyl is final! Rabbit skin glue will crack and disintegrate, after it becomes very hard.
I use PVA to glue a polyester bed sheet to mahogany plywood before I prime it. That's museum quality all the way.
Here is how I make it.

http://www.mauigateway.com/~donjusko/gettingstarted.htm

[email protected]

Don Jusko

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Painting tips (http://www.mauigateway.com/~donjusko/fine2.htm)

rhoward
12-19-2000, 07:54 AM
Originally posted by donjusko:
That's museum quality all the way.


Uh, which museum is that, Don?

Does this mean that all of those big Rubens, Velasquez, Rembrandt (and darned near the entire history of art's) paintings which are without any cracks are not sized with hide glue? Perhaps, those guys knew how to do it and the guys who have trouble with it don't know. There's always been a lot of 'don't know' out there in the art world. That has the salubrious effect of removing those painters from the rolls after a few years.

As for the luan plywood, that stuff is DEFINITELY not ready for prime time. It is used for flooring underlayment because it's cheaper than good hardboard. Simply put, it's the cheapest stuff out there. The way it gets cheap is buy cutting corners in manufacturing. It's just a little more permanent than compressed toilet paper...and cheaper. However, your choice of a polyester bedsheet is to be commended. That will certainly outlast linen -- were that it was attached to a reasonably decent support.

One of our partners actually makes cradled wood panels for museums...true museum quality. They are very, very expensive to make, but museums don't mind paying the money for true museum quality. I suspect they'd toss him out on his ear if he tried to foist some luan mahogany underlayment on them.

Wood panels are a thig of beauty. Luan is not.


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figgby
12-29-2000, 12:39 AM
why not paint on panels of abs plastic, a chemist at dupont told me it had a life span of 1000-2000 years, and forget the priming. I mean you can prime it if you want but it is not a must do. It comes in 4x8 sheets for about $60 dollars a sheet, for black and it does come in colors, and can be cut with a saw. it is also available in the form of a sailcloth material. It is hard to stretch because it does not shrink with water or primer. seems to me a lot simpler than all of the above processes.

rhoward
12-29-2000, 08:50 AM
Originally posted by figgby:
why not paint on panels of abs plastic, a chemist at dupont told me it had a life span of 1000-2000 years, .


Far better is CorTen steel coated with nitrile black. I will last 500,000 years (which is only prudent, given the quality of art under discussion) and the nitrile coating reflects radar beams,making it virtually invisible to targetting artillery. SToring it in a temperature and humidity controlled bunker with ten foot-thick reinforced concrete walls will also insure that these examples of our most precious personal expressions will outlive the
<FONT COLOR="Red"><FONT size="5"><FONT face="Arial"></FONT f></FONT s></FONT c> sign that we put next to our signatures. We're talking IMPORTANT works of art, and it's our duty to unborn generations to inflict our work on them, so pay attention to the longevity of the art materials. Ignoring craft, content, originality and skill is okay. http://www.wetcanvas.com/ubb/tongue.gif

I dunno. I thought that I had a pretty big ego, but maybe my ego isn't big enough to worry about my work being of interest in a few hundred years.

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[This message has been edited by rhoward (edited December 29, 2000).]

figgby
12-30-2000, 01:56 PM
I am not sure it is about ego so much as it is about dealing with the problems of conservation. I have not encounter info on the materials you have mentioned and am not sure anything is worth lasting 500,000 years. The discussion here seems to be in the vein of conservation and I am just driving with the traffic so to speak. Do you have any info on abs plastic supports?

rhoward
12-30-2000, 10:51 PM
Originally posted by figgby:
Do you have any info on abs plastic supports?

Yes. They are plastic. Does plastic fit with your aesthetic? Do you like the feel and look of plastic? Do you prize objects made of plastic?

If you like the look and feel of plastic, you will use it despite what conservators say.

Working with conservators in mind is like buying a car on the basis of how easy it is to do body work after you get into an accident. Somehow, I think a car should be purchased for other reasons, just as the selection of art materials should be guided by the aesthetic effect we seek rather than what the guys in the repair shop say...after all, they are not painters, they're conservators.



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357 Mag
12-30-2000, 11:20 PM
I've used both masonite and luan. The grain of luan makes it a neat alternative, and it's very light. Ted Goershner uses luan. Of course it has a tendency to warp but so what? Once it's in the frame, no problem. Oil primer on luan makes a pretty good surface to paint on. If you're worried about longevity, just use the luan for practice panels.

rhoward
12-31-2000, 09:33 AM
Originally posted by 357 Mag:
I've used both masonite and luan.


Well if you use it, that's good enough for me.


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beauxman
12-31-2000, 01:09 PM
Hey Mag, is it hard to get artist materials in the big house? Just wondering.

Magic Genie
08-13-2003, 01:43 AM
We're working on panels:

1) I got 3/4 inch birch plywood because 1/4" seemed kind of thin and they didn't have anything in between. Thoughts?

2) We get free rolls of white vinyl cloth, and beige muslin cloth. Would either of these substitute for the bedsheets?

3) For oils, do I need to get the Studio Projects Gesso or is there another alkyd gesso (not acrylic) you recommend?

Thanks so much- you're awesome!

Peace,
Genie

stagfoot
08-17-2003, 07:35 PM
back to the question about Pva size, I have read that some conservators no longer recommend it, because after many decades Pva slowly turns from its original near neutral Ph balance to one more acidic, endangering the longevity of linen and cotton.

Luis Guerreiro
08-18-2003, 04:55 PM
Originally posted by rhoward
Conservators are using PVA on old leather, buckskin clothing, fabric and other non-art subjects. It's just carpenter's glue.

I have to agree with the above quoted. PVA is just NOT for Fine Art, no matter even the famous (and infamous) "acid free" PVA marketed. PVA was never designed to last. That says a lot!

Having said that, RSG is hygroscopic, it swells in the presence of atmospheric moisture, so now I only use it for panels and for canvas on panel. I now think it is too mch of a risk on stretched canvas.

Luis

Magic Genie
08-18-2003, 05:19 PM
What should we use for glue to make archival art boards?

Luis Guerreiro
08-18-2003, 05:34 PM
Originally posted by Magic Genie
What should we use for glue to make archival art boards?

Rob will be able to tell you better than me, as I do not deal with art board, normally only panel, canvas fixed on panel and stratched canvas.

I reckon pharmaceutical grade gelatin would be a good choice.

Wait for him to come round to Wetcanvas. Or ask him at Cennini.

Kind regards

Luis

Luis Guerreiro
08-18-2003, 05:37 PM
Originally posted by rhoward
Then a friend came back from Portugal with a Portugese wife and a bunch of bunny glue (smells like glue, not road kill). We made contact with the glue makers (through his wife) and we've been importing it for several years. It's really super stuff. We also get out 376 gram hide glue and technical gelatin from the same source. They are very honorable people to deal with and we have had nothing buy raves about the glues.

Portugal produces two great Fine Art materials:

1. RSG
2. Pure Gum Turpentine (yup, made from maritime pine)

Luis;)

Sketcher
08-18-2003, 08:17 PM
using PVA glue instead of rabbit skin glue will save the lives of cute bunny rabbits with round fluffy tails.

stagfoot
08-18-2003, 09:46 PM
Originally posted by Sketcher
using PVA glue instead of rabbit skin glue will save the lives of cute bunny rabbits with round fluffy tails. Dam their twitchy little noses! Die bunny die! What about using matt acrylic medium as a size and then acrylic gesso on top of this?

David O
08-19-2003, 10:43 AM
Death to the foul bunnies. Evil beasts, all of them.

Luis Guerreiro
08-19-2003, 07:54 PM
Bunnies are not killed for the purpose of making glue from their skins.

Rabit is part of the diet in most Southern European countries. So is hare.

The skins are a by-product.

Most RSG (rabit skin glue) is made these days from skins and bones from a variety of animals, not just rabits. Having said that, pure RSG is available, it is the best glue, although modern conservators will tell you that it is held accountable for the cracking of oils because of its hability to absorb moisture from the air. This is debatable, obviously.

Luis

David O
08-20-2003, 07:27 AM
Well that takes all the fun out of it for me...

Pilan
08-20-2003, 01:17 PM
all of this makes me very curious now. I purchased gamblin pva and have been using it to glue my canvas on masonite.

does anyone use masonite with pva besides me, here on this thread?

I am still confused to what is the best glue to use!

And where can I get it?

thanks

Pilan

Einion
08-20-2003, 06:43 PM
Pilan, you can continue to use your PVA without worry, it's perfectly fine for what you use it for and has far less potential problems associated with it than the various hide glues available today under the misnomer 'rabbit skin glue'.

Einion

Pilan
08-21-2003, 11:45 PM
thanks Einion, I was beginning to wonder but I feel better now.

I like your little quote below, it's a good one :).


Originally posted by Einion
Pilan, you can continue to use your PVA without worry, it's perfectly fine for what you use it for and has far less potential problems associated with it than the various hide glues available today under the misnomer 'rabbit skin glue'.

Einion