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philwms
10-06-2006, 09:59 PM
I am experimenting with grisaille painting - monochrome underpainting for color glazing. The grisaille technique generally needs a very detailed initial layout and drawing, so I'm using very light lines on paper. Grisaille and glazing also are best on a smooth surface. I've been using clear acrylic matte medium over the paper layout before starting the painting, but so far I've been brushing the acrylic medium and the brush strokes are very evident. I tried sanding, but that does not work on acrylic.

Is there a way or acrylic medium that will completely seal a paper surface and can be applied smoothly?

timelady
10-07-2006, 03:25 PM
Sounds to me like you need to rethink your tools - right tools for the job and all that. The effort to completely smooth a piece of paper, eek! ;) Perhaps use hardboard, or bristol board? Or even a different paper - like hot press or something? (I'm not up on all the paper terminology.)

Tina.

philwms
10-07-2006, 05:01 PM
Tina,

Rethinking my tools is not the issue.

When I say smooth, I don't mean like glass... Is that what you think I meant?

I mean smooth so that the grisaille underpainting and subsequent oil paint glazing will flow relatively smoothly instead of pooling in the grain of brush strokes. Is that more clear?

Lady Carol
10-07-2006, 05:17 PM
Hiya Phil, Welcome to the acrylic forum.

I live just up the road from you in Wayne.

You are trying to get rid of the texture of the paper to paint the grisaille on. Have I got the right idea here? I suggest a couple of coats of gesso and applying it with soft brushes rather than the bristle sort. Also paint the grisaille with a soft brush too so you aren't left with brush marks.

Hope this helps.

philwms
10-07-2006, 05:39 PM
Carol... Thanks for your reply...

I guess I was not really clear to start with... Let me start over.

step 1) A line drawing on paper. Rather than transferring the line drawing to a panel for painting, I am... (see step 2)

step 2) ...glueing the paper to a panel using Yes glue - a fantastic product that does not buckle paper and is archival. Next I... (see step 3)

step 3) ...seal the paper using a clear acrylic matte medium so the drawing is visible. Next I... (see step 4)

step 4) ...start painting.

The probelm is in step 3. The only way I know to get the acrylic matte medium onto the paper is using a brush, which produces the unwanted brush stroke grain. Is there a way to apply a clear sealing medium on the paper that ends up being relatively smooth rather than ridged with brush strokes? Acrylics seem to be the answer... just can't figure out how to get them on smoooooothly...

Lady Carol
10-07-2006, 06:35 PM
Now I understand. :o

What sort of brush are you using to apply the medium? Are you brushing all around in all directions or are you brushing in only one direction? I generally don't see brush marks with medium. I use a soft brush to apply the medium but I haven't paid any attention to whether there are brush marks as it hasn't been important.

How about a couple of coats of medium going in different directions?

philwms
10-07-2006, 06:49 PM
I'm using a 2" painter's brush... hmmm... perhaps using a smaller, softer brush would work. However... the eventual endgame for this question is painting the clear medium(gesso) on a panel that is about 4 feet by 7 feet in size. If the smaller softer brush works, I'd do the time, but I'm thinking there must be a better less time intensive way...

MandyB
10-07-2006, 08:43 PM
Hi Philip

Have you tried thinning your medium and applying 2 or more coats? If it's thinner maybe it won't hold the brush strokes so readily. Or maybe you could use one of the thinner mediums, like glazing liquid?

mandy

MandyB
10-07-2006, 08:44 PM
Or yikes even get the airbrush medium and spray it on :-)

Einion
10-07-2006, 10:16 PM
Hi Phil, the obvious first thought is to apply the acrylic medium thinned. You can thin it very heavily and apply multiple coats if necessary (five or six watery coats to roughly equate with one unthinned coat) but roughly 30% water should be enough to make it flow well, so that two coats should do about what you want.

I would use a brush with bristles that are relatively soft; some decorators' brushes are okay - made from fine polyester or nylon - but most of those over here use coarse hog bristle or the nylon equivalent.

Now personally if I had the option I'd like to spray this on, but you'd need a large airbrush or spraygun.

You're working over paper in oils, is that right? Are you prepping the paper itself to seal it from the oil or are you happy that it'll last as long as it'll last?

Einion

philwms
10-07-2006, 11:26 PM
You're working over paper in oils, is that right? Are you prepping the paper itself to seal it from the oil or are you happy that it'll last as long as it'll last?


As I understand it, the paper is properly protected by the acrylic medium as long as the medium completely covers the paper, which is an acid free stock. The paper itself is bonded to a stable backing using the "Yes" archival glue. The backing I'm using is an absorbant wood panel which allows the "Yes" glue to properly set over time under the paper with the non-absorbant acrylic medium. I have spoken with the tech guy at http://www.ganebrothers.com . They manufacture the glue. He says the bond will be archival as long as it is properly maintained like any work of art.

philwms
10-07-2006, 11:39 PM
Or yikes even get the airbrush medium and spray it on :-)

Yikes? ... what is the "airbrush medium"...?

tubbekans
10-08-2006, 12:27 AM
Thinning the medium with water should help with eliminating brush strokes. And using a large sponge brush should help, and they are pretty inexpensive. You will probably want to lay the surface down flat when priming it as the thin medium might run if its vertical. Also use slow strokes and try not to brush it fast or you can end up with bubbles in the medium layer. I like bubbles but you might not.:) Probably waiting 20 to 30 minutes between costs of medium woud be good too, just to give it plenty of time to dry and not be tacky and dragging on the brush when you do the next layer. Airbrush medium is acrylic medium made for an airbrush. It is very thin and goes through an airbrush purty well. If you decide to air brush it you can use regular medium but thin it with water. And flush the airbrush out with plain water when done or water and a little ammoina/soap. It's really best to take it apart and clean it. Using an airbrush would avoid the problem of smearing the drawing lines. Oh, they sell spray cans of fixative for pastels or drawings that might be worth trying too. You could probably spray a layer of fixative first to set the lines and then add some acrylic medium layers to really smooth things out.

jeff m
10-08-2006, 02:08 AM
For sealing the pencil lines Paul's suggestion of fixative is the easiest.

For smooth application of paint with no brush marks try a mixture of flow aid, paint and water.

philwms
10-08-2006, 07:54 AM
tubbekans ... I'm going to try the thinning, sponge brush method. Sounds like a good possibility... thanks.

Jeff ... What is "flow aid?" An acrylic glazing medium?

MandyB
10-08-2006, 08:30 AM
Yikes? ... what is the "airbrush medium"...?

Hi Philip

Here's the airbrush medium :) (Yikes becuase I just thought of it)

http://www.goldenpaints.com/technicaldata/abmedium.php

mandy

philwms
10-08-2006, 09:39 AM
Thanks Mandy,

I just ordered a small amount to check it out...

philwms
10-09-2006, 08:56 AM
update: so far, 1/3 water and 2/3 clear matte medium applied in several coats with a wide soft brush seems to be working pretty well...

ashlandartist
10-09-2006, 11:36 AM
Hi Phil. I'm not familiar with grisaille, but it sounds interesting.

I've been reviewing everyones comments here and I noticed one things been omitted here. Most likely because you all are "fine" artists.

I used to have the same trouble with brush marks that you're having when I would try to get a smooth finishing coat on hand-painted furniture. Cans of spray sealer work great, but it takes too many cans for a large area. After much trial-and-error (and frustration) I found that a small foam roller works beautifully. Much better than a bristle brush or even a foam brush. But the trick is, as everyone is saying is to thin the varnish.

The foam roller was originally designed for getting into the unusual shapes of radiators. Plus they didn't look good with brush marks when painted either ;) It is now referred to as a "foam" roller or "hot dog" roller. And you can find it easily at Wal-Mart, Lowe's, Home Depot, etc.

Although, I seem to be a bit late with my tip and you already have it under control. Good Luck Phil and POST your picture when you done!!!! Robin

Einion
10-09-2006, 07:08 PM
As I understand it, the paper is properly protected by the acrylic medium as long as the medium completely covers the paper, which is an acid free stock.
It won't be completely sealed from oil penetration in a single layer but it will help. Working on paper you've primed would provide additional protection if you'd like to try that (it'll change how it is to draw on and paint over, as you'd expect).

Have you thought about using YUPO as an alternative?

After much trial-and-error (and frustration) I found that a small foam roller works beautifully. Much better than a bristle brush or even a foam brush. But the trick is, as everyone is saying is to thin the varnish.
Great suggestion Robin, should have thought to suggest it myself. I even bought two recently for applying primer!

Rollers also drag on the surface less and this can help to lessen any softening of the pencil lines with the first application.

Einion