WetCanvas
Home Member Services Content Areas Tools Info Center WC Partners Shop Help
Channels:
Search for:
in:

Welcome to the WetCanvas forums. You are currently viewing our boards as a guest which gives you limited access to view most discussions, articles and access our other FREE features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload your own photos and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please visit our help center.

Go Back   WetCanvas > Explore Media > Oil Painting
User Name
Password
Register Mark Forums Read

Salute to our Partners
WC! Sponsors

Our Sponsors
Reply  
 
Thread Tools Display Modes
  #1   Report Bad Post  
Old 08-12-2018, 04:21 PM
Phingari Phingari is offline
New Member
 
Join Date: Jul 2018
Posts: 4
 
Question Mixing an oil primer from scratch ---

I have materials lying around that I bought many moons ago (in Spain in the eighties) and want to use them up to prepare a batch of canvases for oil painting.

I am using rabbit skin glue on high quality linen for sizing. It's the primer that I have questions about. I have in my possession several kilos of white lead, titanium white, zinc white, and calcium carbonate -- all powdered pigments. I know how to mix them safely with linseed oil -- but what linseed oil is best for an oil primer -- the cold pressed or the bleached variety (I have both on hand)?

Also could I add titanium white to the white lead, is it worth it? How much would I add? And if I added say 10% of calcium carbonate would it change the absorbancy or influence the drying or change the texture for the better or the worst? Would it make it too brittle? It seems to me the the zinc white would not be a good idea to include in a ground/primer, but I'm open to other opinions.

And is one turpentine more recommended than another? Is pure balsamic turpentine okay? If I understand correctly, I would mix and grind the pigments with as little oil as possible and then add 3 parts turpentine to the mix? Or is there another way to mix and measure this?

Thanks for any suggestions!

Last edited by Phingari : 08-12-2018 at 04:24 PM. Reason: too many spaces, punctuation
Reply With Quote
  #2   Report Bad Post  
Old 08-12-2018, 06:54 PM
ddattler's Avatar
ddattler ddattler is offline
Senior Member
Florida, USA
 
Join Date: Jan 2011
Posts: 407
 
Hails from United States
Re: Mixing an oil primer from scratch ---

As long as the canvas is properly sized, an oil primer is OK. I wouldn't use any oil primer without sizing or gesso first. Oil based paints will break down your linen or canvas over time.

I'm not sure how to answer your pigment questions. I can tell you that zinc white has a tendency to yellow over time. Titanium may be the better choice. Linseed oil will also turn yellow eventually. Some artist and manufacturers use a walnut oil which doesn't suffer the yellowing as much over time. Dick blick's sells pigments, and as I recall there were tips on their site on mixing your paints.

Earthpigments.com has some good basic recipes.

Turpentine in your recipe????
__________________
http://wildlifearts.com
http://www.etsy.com/shop/wildlifeartist
Practice what you know, and it will help to make clear what now you do not know. ~ Rembrandt
In Art, Learning to see is at least as important as the actual creation of Art. ~ George Benedict
Reply With Quote
  #3   Report Bad Post  
Old 08-12-2018, 08:54 PM
contumacious contumacious is offline
Enthusiast
 
Join Date: Dec 2016
Posts: 1,912
 
Re: Mixing an oil primer from scratch ---

A basic recipe is refined linseed and stand oil, white lead pigment, marble powder/calcium carbonate and a little titanium white pigment if you want to intensify the white a bit. The calcium carbonate will make it more absorbent, so test the ratio you add first before making a large batch. Mull it well so that all the particles are well mixed in with the oil.

A suggested ratio starting point:

White lead 7 parts
Titanium White 2 parts
Inert Pigment (chalk, calcium carbonate, etc.) 1 part
Stand Oil 1 part*
Linseed Oil 1 part

A possible alkyd ground variation:

White lead 7 parts
Titanium White 2 parts
Inert Pigment (chalk, calcium carbonate, etc.) 1 part
Stand Oil 1/2 part
Alkyd Resin 1/2 part
Linseed Oil 1 part

* You can replace the Stand Oil portion with Linseed Oil if you wish.

The "parts" are by volume, not weight. You can make an alkyd ground by adding some alkyd resin to the mix for a faster curing time. If you add some alkyd resin - for each "part" of alkyd added simply reduce by the same number of parts for one of your oils. You may need to vary the amount of oil to get the consistency you want.

Normally you don't want to add the turpentine to your main mixture. Add turpentine or OMS to some of the ground for just the first layer. The next layer(s) would have no turpentine in them.

I am not a fan of rabbit skin glue, particularly on canvas that isn't mounted to a rigid panel due to cracking concerns, but it is used by lots of painters. Personally, on un-backed canvas, I would go with a matte acrylic medium, PVA size or some other some size rather than the RSG. Natural Pigments also recommends acrylic dispersion gesso as the size for their lead ground.

https://www.naturalpigments.com/lead-oil-ground.html

http://www.cad-red.com/mt/o_o_cnvs.html

http://www.trueart.info/?page_id=188
Reply With Quote
  #4   Report Bad Post  
Old 08-13-2018, 05:20 AM
Phingari Phingari is offline
New Member
 
Join Date: Jul 2018
Posts: 4
 
Re: Mixing an oil primer from scratch ---

Thanks for the replies!

Acrylic dispersion gesso as a size for oil primer? On linen? I will certainly look into this. PVA size on linen is not optimal, that I know from experience. Anyway, for now it's RSG as I've got two-three kilos of the latter lying around. This project is a lot about using up what I've got, surely in the future I'll be working differently (I will never again be able to find this pure dry white-lead pigment, that I know).

I'm not too worried about the linseed yellowing as it will just be the ground.

I've no walnut oil, so for the moment it's linseed oil. My bleached linseed oil (Goya) is probably much the same as stand oil. So -- question -- would what Contumacious calls linseed oil mean the cold pressed variety? (I've too much of the cold pressed lying around so it would be great to use it). I've no alkyd resin with me at the moment, but it sounds interesting. I will take note for a later date.

I'm a bit wary of the calcium carbonate. I think I'll make two batches of primer so as to leave it out of a (less absorbent) first coat then add it to a second layer. Perhaps I could increase the titanium white then to three parts for the first coat? For the second coat I intend to follow Contumacious' first "recipe" to the letter. Thanks again!

This is great, I'm starting to get excited about this. Many times I've read that white lead gives the most enjoyable ground for oil painting (that's why I bought this dry pigment way back when...), but I've never had the experience myself. Too bad it will take so long to dry before I can report any results...
Reply With Quote
  #5   Report Bad Post  
Old 08-13-2018, 07:36 AM
Gigalot's Avatar
Gigalot Gigalot is online now
A Local Legend
Tbilisi, Georgia
 
Join Date: Jun 2009
Posts: 8,724
 
Hails from Georgia
Re: Mixing an oil primer from scratch ---

Use cold pressed linseed oil as it dries faster than refined oil. Why you need to spend ton of Lead White for oil ground? It is very expensive pigment. You can employ it for oil paint. You will have a trouble to sand such a ground because Lead White is extremely toxic. Just mix Calcium Carbonate, Titanium White and cold pressed linseed oil and grind it for Ground purpose. Finally, add 5% Lead White to this mixture to achieve good drying properties of such gesso. Apply this paste on sized canvas, spread it finely and let it dry.

Use 3 parts of paint grade Calcium Carbonate, 1 part Titanium White. Add linseed oil very carefully and grind finely. Add less oil, mix and then add necessary amount of linseed oil with eyedropper drop by drop.

Last edited by Gigalot : 08-13-2018 at 07:41 AM.
Reply With Quote
  #6   Report Bad Post  
Old 08-13-2018, 02:06 PM
Phingari Phingari is offline
New Member
 
Join Date: Jul 2018
Posts: 4
 
Re: Mixing an oil primer from scratch ---

This is a new proposal! Wouldn't so much calcium carbonate make it too brittle or too absorbent though ? (I'm working on stretched linen.) I was under the impression calcium carbonate works best on rigid surfaces and is more for tempera (when mixed with RSG)...?

What intrigues me most about your suggestion Gigalot is that you offer an alternative solution to mixing a primer from scratch when I've used up my last gram of white lead (or before, I need to give this some thought). But precisely because it is so toxic, I'm not keen on mixing tiny portions of white lead for painting. I am however very interested in discovering the surface that a white-lead oil primer could give me.

I'm glad to hear that cold-pressed linseed oil is more siccative and so not a bad idea in a primer.

For now I'm going with the 7 parts white lead, etc. (P.S. I see "Natural pigments" sells a "Lead Alkyd Ground", which looks like a great product -- it would probably cost a fortune though to ship it to Switzerland -- even if it was legal, which I doubt.)

Thanks everyone!
Reply With Quote
  #7   Report Bad Post  
Old 08-13-2018, 02:54 PM
Gigalot's Avatar
Gigalot Gigalot is online now
A Local Legend
Tbilisi, Georgia
 
Join Date: Jun 2009
Posts: 8,724
 
Hails from Georgia
Re: Mixing an oil primer from scratch ---

In Rembrandt's time, most of Lead White paint was premixed with Calcium Carbonate 1:1. So, 7 parts of pure lead white is a kings quality primer because even Lead White paint was made from equal amounts of chalk and lead carbonate! I only know, that Rembrandt used large amount of very pure silica in his ground. But I know nothing about detailed proportion of his ingredients in primer.

Modern tests of Calcium Carbonate in linseed oil show fine softness of such films. I guess, pure calcium carbonate can be too much soft and it needs Lead White addition to improve drying properties and hardness.

Last edited by Gigalot : 08-13-2018 at 03:52 PM.
Reply With Quote
  #8   Report Bad Post  
Old 08-13-2018, 04:09 PM
Gigalot's Avatar
Gigalot Gigalot is online now
A Local Legend
Tbilisi, Georgia
 
Join Date: Jun 2009
Posts: 8,724
 
Hails from Georgia
Re: Mixing an oil primer from scratch ---

I did my own test with dispersed eggshell white into refined linseed oil to check absorbency, drying properties, mechanical properties and color of dried paint film. It is ivory colored paint film, it has tendency to wrinkle if applied thick 0,2 mm, it is dried and somewhat rubbery substance after 30 days of drying time and it achieve high gloss. It still has a drying paint odor.

I guess, you need about 6 month to get well dried film

Eggshell white was finely grind with water on granite plate with agate muller during two hours. After that, fine pigment was dried and prepared with pure refined oil to creamy paste.
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 06:32 AM.


© 2014 F+W All rights reserved.