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Wayne Gaudon
05-08-2002, 02:09 PM
I have heard that Garrett Copal Medium beats the heck out of other Copal Mediums. What qualities would make WN Copal Medium inferior to Garrett Copal Medium .. if indeed they are?

It's a case of availabily .. Garrett isn't and WN is.

Thanks,

LarrySeiler
05-08-2002, 04:40 PM
Many store shelved varieties are synthetic cheaper resins, thus easier for the stores to order and stock. However, they simply do not behave traditionally and historically as oil of copal, or copal medium is suppose to.

As for this specific brand, WN....I'll wait to hear what others have to say, but Ron has himself posted here to field questions.

As for getting the product from Garrett....availability is basically an email away..an order, whatever. Not convenient like walking in a store tomorrow, but his company ships out promptly.

Hhhmm....okay, wait a minute...I found the url forum site where we talked in length about Garrett's copal, other products...and then Ron Garrett himself jumps in and explains things in great length. Turns out to be one heck of a good thread to read. Here, I'll post a link for anyone interested to read thru it....

http://www.wetcanvas.com/forums/showthread.php?threadid=12731&highlight=Garrett+copal+medium

Larry

Wayne Gaudon
05-08-2002, 10:11 PM
Thanks Larry .. I checked out the thread .. good stuff. I will check into ordering it from whereever to Canada and see what the cost will be.

Grumbracher makes 2 different Copals .. Copal Medium and Medium 3 .. the Copal Medium has an acrylic resin in it which would make it a non-want but the Medium 3 does not.
Contents of Medium 3:
Turpentine Damar Gum D-Limonene Polymerized Linseed Oil Copal

LarrySeiler
05-08-2002, 10:16 PM
Originally posted by Wayne Gaudon
Medium 3 does not.
Contents of Medium 3:
Turpentine Damar Gum D-Limonene Polymerized Linseed Oil Copal

hhmmm...maybe ask Ron about this one. For one, what is "polymerized" linseed oil copal??? Any time I see the word "polymer" it is usually associated with acrylic, as that typically is what polymer is.

Whatever you choose to use, it will be interesting to hear your take on it.

Larry

Wayne Gaudon
05-09-2002, 06:10 AM
Should read this way.

Turpentine
Damar Gum
D-Limonene
Polymerized Linseed Oil
Copal

.. I bough some last night but I am going to order the Garrett one as well .. I did a painting last night and the biggest thing I noticed is that it makes the paint buttery but tacky and seems to help the paint spread under the knife and mix on the canvas with some nice flow.. will have to do a few to get the right amount of mixtures and to see if I get any benefits.

Thanks for you help. Sent the email last night to find out about shipping to Canada.

later

blondheim12
05-09-2002, 07:08 AM
Wayne,
Try Belize Copal Medium from http://studioproducts.com
It beats the heck out of all of them in my opinion. great stuff.
I use 4 parts Belize Copal with one part beeswax for a wonderful medium. You can also just use the Belize Copal by it'self.
Love,
Linda
http://pleinairflorida.org

LarrySeiler
05-09-2002, 07:08 AM
in general...that's what the medium should do for you...though I'm not aware how this copal chemically will all work out, if it will have a "yellowing" or brittle cracking issue that others have tried to associate with copal.

Again....(I don't know the historical formula....but the Garrett family seems to and sticks to it), but from what I've read in all the old teachers of the late 1800's and early 1900's...the oil of copal they used then did not crack, yellow...etc;

Sounds as far as making the paint ready to be used with ease though, that you're on your way!

Larry

LarrySeiler
05-09-2002, 07:50 AM
Originally posted by blondheim12
Wayne,
Try Belize Copal Medium from http://studioproducts.com
It beats the heck out of all of them in my opinion. great stuff.
I use 4 parts Belize Copal with one part beeswax for a wonderful medium. You can also just use the Belize Copal by it'self.
Love,
Linda



yeah....Rob is known for some great products too! A good painter as well. I've heard of this medium as well from somewhere Linda, glad you brought it up. Choices are good. We can be thankful there are a number of sources in case some of them become one day unavailable for one reason or another.

Beeswax tends to keep the surface a bit softer and flexible. I wonder if you added the beeswax Linda as a result of hearing something about the tendency of copal to crack or get brittle, or just enjoy its texture?

I used more beeswax years ago because it too has a unique way of capturing and holding physical light, and lends toward natural impasto'ish work. Hhhmmm....I have a big bottle of that here yet. Perhaps I should have a bit of fun and add some of that as well for particular areas.

Yeeeeowwww.....painting is fun!
:clap:
Larry

Wayne Gaudon
05-09-2002, 09:51 AM
Linda .. I will definately check this one out as well .. price will dictate the matter as both come from reputable painter's suggestions (yours and Larry's). I once read that beewax repells dust when used as a varnish .. wonder if it has the same effect as a medium.

Thanks both .. I will do my homework on this one.

Larry, think I see the difference .. Grumbracker used Polomyrized Linseed Oil which mean boiled and not cold pressed so if my reading and understanding is on the same level, it should darken faster than a medium that uses cold pressed linseed oil if the difference is amountable to any great difference.

blondheim12
05-09-2002, 11:08 AM
Larry,
I had done alot of research on mediums and wasn't worried about the resin copals. Most of the talk about them darkening and cracking seems to be myth. Some of the non resin(cheap Imitation Copals) are in fact, bad to use. You get what you pay for. I use the best possible materials I can get.

Rob knew I was a plein air painter and was using his Belize Copal. He felt that adding the beeswax would really enhance the alla prima method of plein air painting. He was right. it is a lovely medium. The paint stays where I put it. It also has a rich color glow without the overly shiny look of some mediums and varnishes.It stays the way it dries and does not leave the dull look that dried oil paint has without varnish.
For me that is really important, as I often sell paintings long before they would need to be varnished with conventional mediums.
I t is really nice. Try the beeswax and see how you like it. Rob reccomends 4 part copal to one part beeswax. I get my wax from him too. Excellent products.
Love,
Linda

G.L. Hoff
05-09-2002, 11:49 AM
Originally posted by blondheim12
Rob knew I was a plein air painter and was using his Belize Copal. He felt that adding the beeswax would really enhance the alla prima method of plein air painting. He was right. it is a lovely medium. The paint stays where I put it. It also has a rich color glow without the overly shiny look of some mediums and varnishes.It stays the way it dries and does not leave the dull look that dried oil paint has without varnish.I get my wax from him too. Excellent products.
Love,
Linda

Couldn't agree more...beeswax medium (made either with copal or even with just a bit of turps) is wonderful stuff. Makes the paint smooth and soft and yet keeps the chroma high. Dries quickly, doesn't dull. And the Studio Products stuff is just the best.

Cheers

Wayne Gaudon
05-09-2002, 03:14 PM
Copy of my email to John Garrett:

Larry Iseiler was the guy who promoted you. Said you gave him a sampel and he was snagged. LOL
Can you tell me the difference in the concentrate and the heavy and which is the better purchase? Right now
I am testing a bottle of Grumbracher 111 Medium and I find it a little tacky. Will yours run smoother?
Here are the ingredients of Grumbracher.
Turpentine
Damar Gum
D-Limonene
Polymerized Linseed Oil
Copal

Thanks,
Wayne

Wayne,
The copal medium is really a two part system. The concentrate is an additive to the paint on the palette and is used at the rate of one or two drops per inch of paint as it come from the tube and is mixed thoroughly on the palette with the knife. It is what puts the resin into the paint. The medium is used for thinning and glazing. If, by chance, you use lead based paints you, will need to add up to 6 drops per inch of paint to overcome the soap in the paint. Concentrate will keep the paint where it is put and add brilliance and luminosity to the paint and protect it from enviromental damage. There will be no need to varnish the painting as the resin in the paint seals it and provides for a more uniform drying time with all the colors. The concentrate also will help the paint to lay smoother and provide a smoth transition from color to color and from brushstroke to brushstroke. I refer you to http://www.garrettcopal.com/newpage 4.htm for further detail in technique. I am surprised that Grumbacher is using actual copal in there medium as their "copal medium" contains no copal at all. My ingredients are: standoil, copal, and pure gum spirits of turpentine, for the medium and stand oil and copal for the concentrate.

Ron Garrett


Help..

$19.95 Belize Copal 5 oz. bottle
CC 2 oz. (59ml) Copal Concentrate $20.00

CMH 16 oz. (473ml) Copal Medium Heavy $40.00


Question for Larry
.. as per this I conclude that I should be using the concentrate and not the medium as I am not glazing or layering, I am mixing with paint. Am I correct in that deduction?.


Linda, the Belize Copal seems much cheaper as I can get 5 oz of it for the price of 2 oz of the concentrate of Garretts but if the Belize Copal medium is the same consistency as Garrett Copal Medium then I can get 16 oz of the Garrett for the price of 10 oz of the Belize Copal.

This is getting tougher.
Think I will send another email to John.

LarrySeiler
05-09-2002, 06:28 PM
Well Wayne...you got me happy with Ron's copal, Linda happy with Rob's... and from where I sit you probably couldn't go wrong with either of our recommendations.

I for one am glad for the thread, as I'm going to add some of my beeswax to the mix just for the fun of it as I used to enjoy using it years ago. Doing so, not because I'm unhappy with what I'm using now...just to see and experience what happens and hope for something cool!

As for what I use...it doesn' t have a whole lot of difference for me that I detect. The copal with the turp has "turp"... the concentrate seems to be a bit more buttery. Go with your gut instinct and just try it. Get a small amount of Rob's if its cheaper just to try it and get a feel for it. Later, when you feel you can afford it easier try Ron's concentrate.

Larry

Wayne Gaudon
05-09-2002, 07:12 PM
I wrote Ron again so I will post that as well when I get it. I asked him about adding BeesWax .. benefit or not?

blondheim12
05-09-2002, 09:11 PM
Wayne,
You can buy the concentrates from Rob too, but the Belize is not a concentrate. It is designed to use as is.
I don't know if that helps you.
I would suggest like Larry, that you try them both and see which you like better.
Love,
Linda

G.L. Hoff
05-09-2002, 09:54 PM
Also, FWIW, you can also get a copal varnish (I don't think it's a boiled varnish) from Robert Doak. I'm pretty sure he makes his own.

He recommends mixing it with his sun-thickened walnut oil and various amounts of turps to make a really fine medium...For painting medium, Robert calls for 1 part oil (walnut or linseed), 4 parts turps, 1/2 part copal varnish. For retouch it's 1 part copal varnish, 4 parts turps. For glazing, 1 part oil, 2 parts turps, 1/2 part copal varnish.

I've been using his copal varnish sporadically for a few months and really like it.

Regards

Wayne Gaudon
05-10-2002, 01:33 PM
Thanks Larry & Linda:
I will try the medium first and if it doesn't do the job then I will try the concentrate but seems to me you both use the medium and it gets the job done so if it works for you it will work for me.

As usual .. money dictates so I've gone with Garrett as I get an extra 6 ozs for the same money.


G.L. Hoff . thanks for the additional information.

Wayne Gaudon
05-15-2002, 08:52 PM
I wrote Ron and asked him about adding BeesWax to his medium and he said he could see no benefit. In fact he said he could only think of it as being a possible problem. Said he couldn't see why anyone would want to add a soft wax to a hard but flexible resin. Being as he makes the stuff I would venture that he knows what he is talking about.

Later,

blondheim12
05-15-2002, 10:01 PM
To each his own Wayne. All I know is that it makes a lovely medium and I like it. That's reason enough for me. I don't know anything about Ron Garrett, but I do know that Rob Howard is a very fine painter. He and others on his forum add beeswax to their mediums. It makes for a lovely surface. Lets just paint and be happy with our own mediums, whatever they are.
Love,
Linda

walden
05-15-2002, 10:02 PM
Larry, do you use the medium or the concentrate? When I read another thread (or maybe a demo, can't remember) where you commented on this, you spoke of adding a few drops to the paint on your palette, but from the email Wayne got it sounds like that's how one would use the concentrate, rather than the medium. I'm so confused!!! I have some of the medium on order, but now I'm wondering if I'm getting the right thing?

LarrySeiler
05-15-2002, 10:18 PM
I have both Lisa....

You'll have NO problem with what you purchased. It will work fine.

Think of what a concentrate is....usually thicker, right? So, it allows the paint to be a bit stiffer. Secondly...I use the concentrate for lead white paint. Lead white evidently has soaps in them, and the concentrate works better with it.

The regular copal medium which you purchased has a tad bit of turps in it. If I should like to paint with "some" layers in the thin to thick vein of working...or find myself going back later, I'll use the concentrate for finishing last strokes.

However, for most situations...being that I'll start and finish a piece in one sitting...ie, "alla prima" ...the regular copal medium you've ordered is what I will use. You'll be happy. Once you get it, if you have any questions, feel free to ask me. Basically, I add 1-2 drops with a palette knife per inch ribbon of paint. Then mix it up well with the knife into a buttery state. The colors will shew like jewels...stick right where you put them.

Larry

LarrySeiler
05-15-2002, 10:19 PM
that's cool Gary....nice to know other options and what's available for all interested.

Larry

walden
05-15-2002, 11:26 PM
That's a relief, thanks, Larry! I almost always finish in a single session, and getting an even sheen without having to varnish really appeals to me. I've done some of that varnishing, and it's a real pain, particularly for someone who owns cats. :D

Wayne Gaudon
05-16-2002, 05:54 AM
:) Linda :) .. Please don't be offended.
.. Ron's advice was pertaining to his copal and not the Belize that you use. As you say, each artist has their own opinions as to the use and effects of different matters and I asked about his copal not yours. As stated earlier, it's the cash flow that sent me Ron's way as I am only learning and selling is at least six months or a year away.

Lisa
.. From the formulas provided, Ron's concentrate and the medium are the same copal .. the medium is cut with turps and the concentrate isn't so it's just a thicker version of the same thing.

He sent mine on Monday and I'm anxiously awaiting the stuff. Went out yesterday to do a plein air .. got half way through it and was being eaten alive by red ants .. moved my pallet over a few yards, went back got the canvas and stuff, got to the pallet and couldn't see the paint through the ants .. Out of there.. scraped the canvas and still picking ants off my clothes for the next hour .. I must be more choosy of my spots .. can't wait for my easle to come (backorder) so I can sit or stand up instead of sitting on the turf.

Later,

blondheim12
05-16-2002, 06:04 AM
I'm not offended in the least Wayne. I'm sorry if I sounded that way. I just didn't want to get into that old stale argument about Who's is better, yours or mine?

As you say there are a million different mediums. If we find one we like, it's great!!!
Love,
Linda

Wayne Gaudon
05-16-2002, 07:02 AM
That's good! I wasn't sure if you knew that I was talking one copal and not all copals with regard to the beeswax and I just wanted to make sure you didn't think I was blasting you or other artists' taste in how to do things. It's such an individual thing that makes one better than the other and in a lot of cases one isn't, it's just taste.

It's funny how that one line (Whatever gets you through the night. (John Lenon) pertains to so many different things .. There is always better, always worse but if you are happy with what you have, then all else is irrelevent.

Thanks for all you advice and understanding,

walden
05-16-2002, 07:21 AM
Linda, the way you use the Belize copal and beeswax, do you feel that it is necessary to varnish-- either for protection or to bring up or even out the gloss?

LarrySeiler
05-16-2002, 08:22 AM
I'm sure there was no offense meant, and doubly sure none was taken. Its a good question though. I mean, I have some wax around too and just remembering the thick luminiscent stuff working with it a number of years ago...the idea of it mentioned here was immediately entertaining.

Whether or not the softness of the wax is a good marriage with the hardness of the resin and what its long term archival resiliency is...I don't know, and perhaps many don't. I think your inquisitiveness on this might be a legitimate concern. I'll have to weigh that over.

I don't know anything about Belize....and Rob being the "chemist" so to speak with that would perhaps know better.

A lot of times too, its who you get to know. Those that get to know Rob, respect his work as an artist, etc...are understandably going to feel comfortable.

I got to know Ron about six years or so ago now. Perhaps seven. I stood in the gap for a couple of years while his wife was fighting a frightfull physical affliction...by praying for them and their family. She went thru a healing....and from what I understand is doing fine today. I know that Rob has many fine products, and one will learn to appreciate his expertise. I know that Ron's product, the copal...is his family's only product. So, for a different reason entirely I imagine his is as good as it comes too.

Either way...we're all just learning here. Whatever anyone chooses as a medium, if it works that's cool. I know for one, as a teacher...that when you stop learning....you stop growing. So keep investigating all, feel free to share. I figure, this old dog still might per chance learn something. Up until this thread, I was not aware of Rob's Belize, or Gary's suggestion of Robert Doak's formula. So...that's cool!

Larry

Wayne Gaudon
05-16-2002, 08:48 AM
I would like to hear from anyone who has used BeeWax as a varnish. I have some paintings I will need to varnish and I read once it is superb because it pushes dust away from itself but I have no idea on how to use it.

Does anyone have any experience using it solely as a varish and not a medium?

blondheim12
05-16-2002, 09:18 AM
Originally posted by Wayne Gaudon
I would like to hear from anyone who has used BeeWax as a varnish. I have some paintings I will need to varnish and I read once it is superb because it pushes dust away from itself but I have no idea on how to use it.

Does anyone have any experience using it solely as a varish and not a medium?

Wayne,
If you go to studioproducts.com and check in the forums you will find out alot about varnishing techgniques and mediums. There are extensive posts about both.

Lisa,
The reason I like the copal and bees wax mediums either together or just copal is that the varnishing becomes unnecessary for the most part. Since I often sell paintings shortly after completion, that's the main reason I switched to that medium. It gives a lovely surface without the dulling effects of dried paint without varnish. You can varnish after a safe period of time. Spray mastic would be the best for that particular medium, according to the folks on studioproducts forum.
Love,
Linda

Wayne Gaudon
05-16-2002, 09:55 AM
Thank you.

Wayne Gaudon
05-16-2002, 10:55 AM
Been digging and here are my observations based on the materials I could find concerning White Bee Wax.

Wax adds to the handling qualities and produces a matte finish
if used in quantity. Moderate use will just dull the High Gloss finish somewhat .. sort of like a Semi-Gloss and far above the standards of a Matte finish. Quantities of what constitued a good and proper mixture to acquire either or is something one would have to play with.

It was recommended for outdoor sketches as lots of wax in the
paint sets up quickly and makes it easier to transport paintings.

If used in quantity it will attract dust but the dust won't stick to it as a buff will get rid of it. If used in paint it will harden with the paint and will not be attract dust as normal wax does.

If mixed with varnish you should warm both mixtures before combination and the canvas should also be warmed (with a brush) before applying.

If anyone can add or subtract to these that would be fine.

walden
05-16-2002, 01:52 PM
Thanks, Linda & Wayne-- this is a hugely informative thread.

blondheim12
05-16-2002, 05:58 PM
It was recommended for outdoor sketches as lots of wax in the
paint sets up quickly and makes it easier to transport paintings.

Exactly Wayne,
That is one of the big pluses for it in plein air painting, not to mention that the strokes stay where you lay them.
Even when the painting is not glossy because of the beeswax added, it still looks great with lovely color. Not like oil paint that is dull when dry.
Your facts are correct asfar as I know. You can varnish with beeswax and buff it too.
Love,
Linda

Wayne Gaudon
05-16-2002, 06:11 PM
Thanks Linda .. I found the lower luster interesting as I don't really like a total high gloss as I find it glares more than it should, so I will be experimenting. First I will do a few pieces with out the wax and then I will do a few with it and base my future paintings on how I like the results of both case studies. Now, if only I had my medium .. oh well, should get it next week I guess as it's a long weekend coming up and I don't ever seem to get any mail the day before a long weekend .. don't know why that is.

Later,

blondheim12
05-17-2002, 05:55 AM
Wayne,
Try using 4 parts copal to one part bees wax first. If it loses too much of it's gloss to suit you, try five parts copal to one part bees wax.
Oh, I forgot to tell you the other benefit. The copal/ wax medium lasts incredibly long compared to just copal by itsself.
Love,
Linda
http://pleinairflorida.org

Wayne Gaudon
05-17-2002, 07:07 AM
Question for you Linda.

The BeesWax .. will any pure White BeesWax work or is there some special brand that does the magic. Also, as I've never see this stuff in action, do you melt the wax into the medium. How exactly is it done.
Hopefully, I can get the wax from a Canadian supplier to avoid the exchange and duty. Government Crooks!

LarrySeiler
05-17-2002, 08:05 AM
I have used and still have a nice size bottle of Dorland's Wax Medium, and I just took a small painting knife sized amount to mix with paint. Though...I'll be curious too on how it should be handled with copal. I would think though, one could just mix it in with the paint, then add the copal.

I've never heard the mixing of the two before, so I'll be curious to hear of the results. I may dabble myself...but when I have time, I'm going to do a bit of reading myself.

Using the copal with just a couple drops or so in a ribbon of paint will bring a nice sheen, but not overpowering. It doesn't get overly glossy or slick unless you paint it thick.

In old master's glazing days...they would brush out a layer of the copal over the paint's dry surface...then paint freshly directly into the copal. Let it dry, and do another layer. That produces that slick gloss effect.

Used impasto'ish however, and in an alla prima method, you get simply a nice sheen somewhat on the matte side.

Larry

Wayne Gaudon
05-18-2002, 06:48 AM
.. All I have so far .. Please feel free to add any and all information relating to the use of BeesWax

Question:
When adding BeesWax to a Copal Medium, how much is enough and will any Pure White BeesWax work. Also, is it a liquid form when added to the medium?

Answer:
Both the wax and the medium should be gently warmed before mixing. Do not overheat or cook it or the resin can sparate out.
Any high quality beeswax will work. The problem is that a great deal of the tuff sold as pure beeswax is adulterated. Beeswax should smell rich, like warm honey.

Question:
This may sound overly dumb but I am completely new to this. Does this mean I can mix my portions of medium and wax and then bottle the mixture for use over the duration of the bottle.

Answer
That should work. Because there's no big chemical interchange going on, the mix should be relatively stable. You'll probably have to warm it before every use, but that's no big problem.

Question
OK .. warming it up after the mixture is made .. could the rewarming of the bottle be done by holding it in ones hand or wrapped in a warm cloth .. or is the warming of a heavier concern like actual heat from a stove or such?

Answer:
I just put some in my small tin medium cup (the common store bought kind) and wave it over a candle flame. Does the trick for me.

blondheim12
05-18-2002, 07:31 AM
I warm the beeswax over a waterbath. Then I mix it into the copal medium. 4 parts copal to one part BW. I use Studio products beeswax. Great stuff.
Love,
Linda
http://pleinairflorida.org

Wayne Gaudon
05-18-2002, 12:05 PM
Linda, do you have to warm it again when you take it outside for Plein Air?

blondheim12
05-18-2002, 02:49 PM
Originally posted by Wayne Gaudon
Linda, do you have to warm it again when you take it outside for Plein Air?
No Wayne,
I don't rewarm it. I'm sure you could though. Here in Florida, it would only be stiff in the winter outside. It's getting pretty hot here now. I'm usuing a french easel umbrella these days, so no heating required.
Love,
Linda
http://pleinairflorida.org

Wayne Gaudon
05-18-2002, 06:34 PM
OK .. thanks tons for all you help ..

raison d etre
05-22-2002, 12:01 AM
Larry,

A polymer is not an acrylic. Acrylic is a product produced by the polymerization of certain synthetic compounds.

Stand oil, I believe is a good example of cross linked lindseed oil. It's still a natural oil just condensed so to speak. Just thought I'd throw that in. :-)

LarrySeiler
05-22-2002, 12:29 AM
Originally posted by raison d etre
Larry,

A polymer is not an acrylic. Acrylic is a product produced by the polymerization of certain synthetic compounds.

Stand oil, I believe is a good example of cross linked lindseed oil. It's still a natural oil just condensed so to speak. Just thought I'd throw that in. :-)

appreciate the correction....thanks. I must have picked up that association seeing "polymer" so frequently applied to plastics as a product.

Larry

sarkana
05-23-2002, 11:43 AM
if you're on a budget or just want to experiment, acquire some copal resin and dissolve it in some turpentine. i got some at the herbal supply here in new york (its a common ingredient in incense). you can of course get more high quality stuff from exotic locales via doak or studioproducts.

i dissolved the copal in some in turps with a dollop of oil of spike lavender. when dissolved, i strained it for impurities. then i stirred in some sun oil (stand oil works too). an excellent medium!

i haven't tried it with beeswax but i think that's a great idea! i sometimes use a thinned matte damar as a painting medium.

Wayne Gaudon
05-23-2002, 11:49 AM
Thank you
.. it's all in the knowing where to find the ingredients and if they are local or not. I remember a similar situtation with the water beds from years ago. A little bottle of solution from the bed sellers was 20.00 and a gallon of the same solution under it's chemical name from a pool company was 5.00 .. go figure.

Einion
05-23-2002, 07:34 PM
Originally posted by blondheim12
Most of the talk about them darkening and cracking seems to be myth.
Really? Sources please. There is a reason copal is no longer used in picture varnishes, the word ditto comes to mind when talking about its use in a painting medium :D

Originally posted by Wayne Gaudon
...protect it from enviromental damage. There will be no need to varnish the painting as the resin in the paint seals it...
ROFLMAO

No offense to Mr. Garrett but geez! Even if we didn't know about varnishing's benefits simple logic would reveal that the only way to protect a paint film from dust, abrasion and so forth is to separate these effects from the paint film itself. There are only two ways to do this: varnishing or behind glass.

Not all oil paintings can or should be varnished, but where it is appropriate it is the better of the two options. If you don't varnish glazing is the only alternative and since almost nobody likes to do this, and it creates a whole set of its own problems, it doesn't really leave a whole lot of options does it? If one doesn't protect the finished painting somehow, you will have run into the same problems present in so much modern painting, Rothkos being a classic example.

Einion

raison d etre
05-23-2002, 07:35 PM
Wayne,

Oh my goodness, I just looked at your paintings. You state you started just his Januaruy? Look at you go.!!!! It takes me 3 weeks to complee an oil, even when I have 2-3 going at once. Pastels take at least a weeks just to work look, walk away ans work again. How do you do it? Are you using fast drying or water soluable?

I love it

Wayne Gaudon
05-23-2002, 08:01 PM
Einion
.. the other side of the coin .. I guess the only way I'll know for sure is to put a painting aside and keep it and have my granddaughter check it when she is my age.

raison d etre

Thank you .. no, I use regular oil but I paint Alla Prima/One Sitting/Heavy Paint. Most of my pieces are finished in a minimum of 4 hours .. if it takes longer than that it only means I'm struggling so it won't be as good as the piece that took 3 hours.

LarrySeiler
05-23-2002, 11:31 PM
Originally posted by Einion

quote:
Originally posted by blondheim12
Most of the talk about them darkening and cracking seems to be myth.

Really? Sources please. There is a reason copal is no longer used in picture varnishes, the word ditto comes to mind when talking about its use in a painting medium Einion

In regard to copal as "a painting medium" and concerns about cracking and darkening....I think Ron's response in this thread is pretty exhaustive in defending that allegation.
http://www.wetcanvas.com/forums/showthread.php?threadid=12731&highlight=Garrett+copal+medium

-Larry

Wayne Gaudon
05-24-2002, 07:05 PM
I received my Copal Medium today and gave it an initial run on a Plein Air outing .. it was a monster of an awakening .. I just love it.
There are a few things that I could do with the paint and knife that don't handle the same but there are a lot more that I couldn't do that I can so I can only see an improvement coming in my painting ability once I learn the in and out of this medium.

Still have to figure out how much to add to get the luminious effect but the little I added did make each stroke stay put. I know I am going to like this stuff .. no strong odor either.

LarrySeiler
05-24-2002, 09:57 PM
That's cool to hear Wayne! Just a couple drops per inch ribbon of paint or so that its buttery/whipped like. It'll leave a slight sheen when dry. It does add more jewel-like intensity to the color. You'll just have to experiment a bit to get it to where you like.

Larry

Einion
05-27-2002, 10:53 PM
Originally posted by lseiler
In regard to copal as "a painting medium" and concerns about cracking and darkening....I think Ron's response in this thread is pretty exhaustive in defending that allegation.
Hi Larry, actually if you look at it closely, it's not. I remember the thread and there is some good information there, the list from Taubes especially, but the quotes from Levison, if you check you'll see there is much of really dubious scholarship (if even an amateur can spot them!) Notice in particular there is no comment on darkening or yellowing. There is no real defence of copal's brittleness, Levison only really says something meaningful about the solubility issue which is not in question. If you like I can detail the errors, especially the first part about flexibility, but much of it is not about copal so it's a bit off-topic but does highlight the questionable nature of his authority.

Einion

Titanium
05-28-2002, 08:07 AM
Einion,

I came across some literature I had, where the
author stated that Copals are very specific.
Each tree type producing a different quality
and with individual components, sometimes
not contained in others.

So to test/use Copal you would need only one
tree type .
This would be exhausting.

I have suggested to those wishing to use Copal
to try the easily and permanently accessible
West Indian Copal.[ no tribal wars to deal with].

As to the longevity. Well, their going to use it anyway
because they want to, so yay or nay is a waste of
time.

Hopefully, the user will insist that the Copal Medium
be made under proper stand oil conditions and the
product would then be light in colour.
[ This was the original natural "Alkyd oil resin "]
Titanium

*Incense is also called Copal Resin , not the same thing
at times [ dissolves in mineral spirits cold - warning sign]

LarrySeiler
05-28-2002, 08:24 AM
I have been buying and hoarding old art books of late, by the landscape Impressionist American painters of the late 1800's and early 1900's...Charles Hawthorne, Hensche..etc;

For medium most used what was called "oil of copal"....and practiced this technique called "bleaching"....of their painting when finished.

I'll have to dig more info out of one of the books I have at school, so I'm quoting more directly. Bleaching seems to be a practice many did....and it was for the purpose of taking a painting that might darken, and expose it to direct light for a short period of time. The author said thereafter, the painting would keep its bright color.

Again...it appears from the works I've seen at art museums that the paint is without cracks, does not seem dull of color. Seems nearly as fresh as painting yesterday. Then again...those works are only about 115 years old or less, so longer time yet has not passed.

I'll see what I can dig up, but I find this discussion certainly of interest.

Larry

guillot
05-28-2002, 10:12 AM
What a long read!! But such an informative one. I've often been curious about the use of copal.

Now, thanks to all of you, I know more than I did before!!

Tina

impressionist2
05-29-2002, 07:02 AM
Tina wrote: "Now, thanks to all of you, I know more than I did before!!

Tina"

Tina, Me, too. But, is that a good thing?

Here I am , money in hand , ready to order copal and beeswax.

However, after reading Linda, Larry, Wayne and Einion's posts, I am totally confused. :(

Guess there's nothing to do but try it ( but which brand?) and decide for myself.

I really admire everyone's work who is posting, so that just adds to the confusion.

They say "All things come to those who wait." Perhaps I'll wait a bit more. Maybe the answer will eventually appear. Perhaps some copal will wander across my path.

Did someone mention free sample? :)

Renee

Wayne Gaudon
05-29-2002, 09:20 AM
I know someone who got a freebie from Ron so if you email him with your delima, he may send you one to help you decide. I bought from him because of $$$ (cheaper). There may be an issue with darkening and cracking but from anything I've read it's a half dozen of this and a half dozen of that (one says yea the other nay), and at the moment I'm not painting anything that deserves to outlive me anyway.

Unless I were selling for 5 and 6 figures I figure you get your money's worth if the painting last 10 years. You pay 5 figures for a car and it last all of 4 years before it starts falling apart so if you spend 3 or 4 and you get 10 to 20 years .. hey, where is the problem?


I ordered the medium and Ron sent me a free sample of the condensed version but I won't even go there till I get a good feel for the medium.

Scott Methvin
05-29-2002, 01:13 PM
I have used lots of amber in my oil painting, but not copal. Amber is "grown up" copal. Older and stronger.

The best I have tried is Blockx. (Alchemist amber with walnut oil, really sucks). Studio Product amber is good also. I have also made it myself and have used the resuilts to good effect.

It makes a great permanent varnish for oil paintings and you don't have to wait 6 months. But it is expensive as hell.

Why use copal when you can use amber? Price?

hblenkle
05-29-2002, 02:00 PM
i would like to hear about how liquin and neo meglip, an alkyd version of copal medium, compare to garret's copal medium.

LarrySeiler
06-02-2002, 11:07 AM
I contacted Ron...and asked him to check out this thread and encouraged him to comment.

Ron is a decent guy, and I've felt fortunate to know more and more about his family, general life...etc; By his own admission, he does not like typing all that much, and claims to be slower. I hesitated to share his information at first...because I don't want to commit him to something he doesn't have the time to follow up on.

At any rate, he did spend the time explaining things to me, and I feel it would be a disservice to him if I didn't share it with all.

It won't keep ongoing speculation from happening, or other possible skepticism/disputes....however, I should just let it be taken at face value. If it helps others think it thru more in a way that will be beneficial to them or not....sobeit. At any rate, I edited the personal chat....and paste Ron's response here to the copal itself-

Ron Garrett-
I fail to see any dubious scholorship on Mr. Levisons
part. If anything it may have been my ramblings at fault. I am not a good typist and therefore dread to do much typing. Maybe I will figure out how to use all these wonderful attachments to my computer someday. One post that did bother me was the implication that the reason that copal is no longer used as a medium was that it did crack and yellow. Mr. Levison addressed these issues in his publication by saying,
"Eastlake defines one superiority of oil color as the ability to reflect light from within, depth was contributed to the resultant color by the vehicle. This made possible the development of effective perspective by the Van Eyks. Leonardo further refined the use of fine gradiations from light to dark (sfumato) to increase the impact of light and shadow. The mastery of painting techniques by Rembrant and his handling of glazes, translucent passages, as well as impastos, were made possible by oil-resin vehicles.

Oil paintings carefully crafted in thin layers, like those of Rubens, have held their color well. Where at a time a reliable color was not available, such as for a billiant green, and one reactive and tricky, like Verdigris, had to be used, the skilled artist could manage by isolating such a pigment with varnishes to keep it from contact with other pigments and from the air.

Varnishes were used before the Renaissance period. The resins available were amber, copal, sandrac, mastic, and rosin. The process of distillation had been developed so that natural expudations of petroleum yeilded the earliest used solvent for varnish resins-naptha. By the fifteenth century artists were using turpentine and oil of spike. The cooking of resins into a drying oil was practiced early in the field of decoration, so that the artist had the knowledge to make various kinds of varnish for his technical purposes. Amber from the Baltic regions was available in northern Europe, as was copal in the south from Africa. Commerce between these regions would have made these materials generally available.

Paint films hundreds of years old can be analyzed for pigments by both chemical and microscopic means. It is not so easy to determine whether the fluid of heavy applications were made possible by thickend oil or natural balsams or with hard resins such as amber or copal. Or, for that matter, to determine which of the latter two. What the factors of durability and tendency toward discoloration of such vehicles are is of importance because the appearance of the pigment color is dependent on reasonable retention of color of the binding film in which it lies. A varnish that darkens or fails detracts considerably from the apparent permanency of the pigment.

Until the middle of the seventeenth century when the "colourman," maker of prepared paints for the artist, began to appear, the artist ground his paints in his own atelier or workshop. When making ones own paints the vehicle can be altered to suit the paintings purpose. In today's commercialization of prepared artists' paints in collapsible tubes, such variations in formulation are not practical. The artist is offered one kind of oil paint ground in pure, nuetral unbodied oil. This is designed for the short, crisp paint used for direct, or a la prima, painting. In increasing the flow and leveling quality of the paint and for thin, smooth transparencies for glazing, the artist is supplied various mediums to add to the concentrated tube paint.

For simply thinning the paint he uses oil and or an evaporating solvent such as turpentine or naptha. For these and other desirable changes there are thickened oils of various consistencies (stand oil and sun thickened oil) and mediums composed of cooked oil resin mixtures, usually thinned with turpentine. Or the artist can concoct his own painting mediums with mixtures of stand oil and damar resin solution.

The damar mixtures are questionable in a paint film because the damar portion remains soluable in weak solvents. This could result in some redissolving of the paint film if later cleaned with solvent in restoring or revarnishing. Copal resin-oil cooks are not subject to such danger because in time the copal appears to copolymerize with the oil to become insoluable.

A controversy as to which is preferable still persists from ninteteenth and twentieth century authorities who classify the specially made artist's copal medium with the copal coach and furniture varnishes current before the advent of the present day synthetic finishes. Copal, for one thing, has been presumed to cause serious darkening of the paint film and perhaps also made it too hard and brittle. Insofar as film flexibility is concerned,
anyone experienced in varnish making knows enough to porportion the oil and resin to prevent that.

Since the change in color of the paint vehichle affects the the color produced by the pigment, this is a factor affecting the permanency of the pigment. A study has been made of the yellowing of oils, stand oil and copal oil mediums added to artist's zinc white paint. Zinc white has relative low opacity so that it will exhibit the yellowing of a medium to a maximum degree. The standard white paint, with a safflower oil vehicle, was mixed with various mediums to equal parts with the oil in the paint.
That is, the binder was was dilluted 100%. Actually the addition of the copal painting mediums was a net of 50% since they contain 50% solvent, but this would be the amount the artist would add relative to the other mediums tested.

Duplicate panels were prepared and, after a short preliminary drying period, one set was exposed to diffuse indoor illumination, the other set being covered to determing yellowing in the dark. The immediate object was a seven month test, at the end of which time colormeter readings were taken. The tests however, were left hanging on the wall, one set exposed to indoor lighting of 10 to 15 lumens intensity, the other covered and in the dark. Thirteen years later colormeter readings were again taken and a more thorough analysis made of the results. The aging of the first seven months is reported here.

The degree of yellowing, calculated by the ASTM D 1925 Yellowness Index equation, has greater significance in showing the effect of the use of stand oil and in the incorporation of copal resin in the vehicle than it has of the relative yellowing of the raw oils. The anomalous behavior of the safflower vehicle did not show up in the initial seven months of test and formlative experience developed since prevents such yellowing.

As has been generally recognized, stand oil yellows less than unbodied linseed oil. There is no indication that copal contributes to yellowing. This copal is carefully run in stainless steel kettles at 338 to 349 degrees celcius to the minimum weight loss required to make it soluable when heated with stand oil. This is an entirely different material than that depreciated by some authors in recent years." (Mayer)

I am no chemist. I am just artist and a varnish maker. I learned from my mother, who was Mr. Taubes' teaching assistant, to make the medium and the concentrate. Someone said in your forum there was a good reason that copal medium wasn't being made anymore and they were right. Running the copal and making the medium is hot dangerous work and it takes a trained eye to make it. It gives off choking gases when heated and can flash under certain conditions, but I have found no other medium that handles like it. I am not saying that there aren't better mediums, I haven't tried them all, all I know is that my product handles well and will open up areas that most artrists don't know exist.

I am reminded of the time that I met Julius Johnson, CEO of Dow Chemical. He took me on a tour of the plant in Michigan. He explained to me that for each product that Dow made there were teams of chemists looking at the by products from that product to make more products. Alkyds for artrists paints came from some by product I am sure.

The great thing about alkyds is they don't yellow and they are elastic so some chemist in some paint company decided that this was the resin to use, and the only trouble was that the chemist wasn't an artist. It takes an artist to know the feel of paint and copal mediums give you that feel instantly. Someday they may make an alkyd based medium that will replace copal medium but until that day I will still be in business.

Vios con dios,
Ron



Larry

cobalt fingers
06-03-2002, 11:10 PM
I have to say for the sake for many out there that I like how a painting looks done with a little copal medium (if one must use any medium at all) and I love how it smells. It is not my first choice for mediums for many reasons.

Einion
06-09-2002, 01:06 PM
Hi Larry, thanks for that. Sorry for the delay in answering but I've been offline a lot of late. This could easily be a long one but I'll keep it short by considering only the two points that the detractors of copal argue: yellowing/darkening and brittleness. Copal's insolubility is not open to question, neither is the fact that it will increase transparency and therefore depth.

First: does copal yellow? Well apparently this depends on who you talk to and which source you trust but in a recent survey of varnishes from the National Gallery almost every mention of copal was negative:<blockquote>Those giving evidence to the 1853 Select Committee, and most writers on picture conservation, were united in their criticism of copal/oil varnish....
In his evidence, the 'picture cleaner' Retra Bolton commented that an oil varnish discoloured more quickly and had a greater tendency to disfigure a picture than mastic varnish, as it became browner and attracted more dust...
Charles Dalbon, writing rather later, in 1898, thought copal and drying linseed oil varnish should never be used: it was always yellowish-to-brown, a colour accentuated by time.</blockquote>There is also mention of a mastic varnish, with copal added probably to aid in producing a uniform finish, that was removed after only seven years, probably because the copal had darkened to an unacceptable extent!

Second: is copal hard? Yes, nobody would argue this, but as any high school science course teaches, hardness = brittleness. Consider the quote from Levison:
Copal for one thing has been presumed to cause serious darkening of the paint film and perhaps also made it too hard and brittle. Insofar as film flexibility is concerned, anyone experienced in varnish making knows enough to proportion the oil and resin to prevent that.
Given the current understanding of oil-resin varnishes, this is hardly a good argument to use in support, but let's look at what he states closely. It might not be obvious without prior reading about the issue, but what he is saying is that in varnishes the oil component should be sufficiently high - i.e. it is the oil in the varnish that imparts flexibility, NOT the resin. The resin is there for hardness, not flexibility, as a varnish maker Ron can confirm this. Since we know linseed oil/pigment films become increasingly brittle with age, anything that accelerates or promotes brittleness is by definition bad.

If you use copal medium in the mistaken belief that it imparts flexibility, think hard about this, especially if you paint on canvas. If you use it purely for handling and optical reasons, fair enough, but accept the negative aspects of its use for the long term.

And finally, to show how out-of-date Mr. Levison's comments are:
<I>Paint films hundreds of years old can be analyzed for pigments by both chemical and microscopic means. It is not so easy to determine whether the fluid of heavy applications were made possible by thickend oil or natural balsams or with hard resins such as amber or copal. Or, for that matter, to determine which of the latter two.</I>
It is now possible not only to profile resins but mixes of resins, and the chemical profile can be specific enough for them to determine the origin of the resin - i.e. which species it came from. For example:
<blockquote>This was identified as an oil-containing varnish, based on a variety of copal and Venetian turpentine (larch resin), with heat-bodied walnut oil? The copal component appeared not to be one of the Leguminosae-derived 'hard' African varieties described above. From its agathic acid content, still extant, the source of the resin was an Agathis sp., from the family Araucariaceae, perhaps Manila copal.</blockquote><I>The mastery of painting techniques by Rembrant and his handling of glazes, translucent passages, as well as impastos, were made possible by oil-resin vehicles.</I>
Modern analysis has consistently failed to show resins in Rembrandt's work. I don't have any data to hand but Titanium might have something on this.

Einion

Titanium
06-09-2002, 02:31 PM
Einion,

I have been tip-toeing around this discussion
as I believe whoever wants to use whatever--
will.
I am not much into "pis.ing in the wind". Please
excuse my French.

Alkyd oil resin, took over from Run Copal
oil medium , and requires Stand Oil for plasticity.

I borrowed a book on Titian. Where in the slices of
microscopically examined paint chips are observed
layers of drying oil gone dark brown to black.

Whelte does state that all Drying oils / resins/oleoresins
go dark or brown with time.

To mask the darkening, it seems that you must keep
the mix Pigment Rich / oil poor [ in this case also resin
poor].

Well they can detect , Copal in 19th Century work,
Pine Resin in Renaissance and Baroque work, Amber
in a varnish covering I believe a curtain in Gentileschi.
I have seen mentions of Venice Turpentine.
Mostly quantities stated as TRACES for resins.

Many mentions of heat-bodied Linseed or Walnut Oil.
Apologies if this isn't much help.
Titanium

Wayne Gaudon
06-09-2002, 03:42 PM
This is getting bigger and bigger.

I have done a half dozen or so pieces and I have not found any combination that would allow the piece to keep a uniform sheen. I still have parts of the painting that goes dull finish from total loss of oil for one reason or another after the passage of a few days. Therefore the piece would have to be varnished before I would sell it to anyone.

I do not believe it is due to the mixture of copal medium as I have tried from minute to large doses and with the same results. I have found that different colors seem to require more medium to get to a similar consistency but perhaps they should never be the same consistency. I don't know as I have only played with oils since Chrismas.

What I have found is that the paintings are touch dry a lot faster and that the paint handles nicely when whipped into a buttery consistency with the medium. I also agree with Tim; I like the smell of this stuff but that doesn't really count for anything.


Einion & Titanium & Tim

What medium do you use or do you use any?