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axel9546
04-13-2019, 02:38 AM
Hi guys i found the gesso i have from golden a little stiff!! Can i diluite with water befor apply a coat on the surface? Is bad or bettee?

JCannon
04-13-2019, 08:48 AM
I always dilute with water. I apply in many layers, often sanding. The later layers usually have more water than the later ones. If you find the right consistency, the layer will dry rather flat (that is, without ridges or marks left by the brush), which makes sanding much easier.

The difficult part is getting rid of the tiny little black specks which somehow find their way into every layer, no matter how careful you are.

Adding talc or marble dust to the gesso is a great way to achieve a more absorbent surface, if that's what you prefer.

I also find it useful to begin with a layer of Kilz or some similar primer, which seals the board. Also, you use less gesso if the board is already white(ish) when you apply the first layer.

axel9546
04-13-2019, 09:07 AM
I always dilute with water. I apply in many layers, often sanding. The later layers usually have more water than the later ones. If you find the right consistency, the layer will dry rather flat (that is, without ridges or marks left by the brush), which makes sanding much easier.

The difficult part is getting rid of the tiny little black specks which somehow find their way into every layer, no matter how careful you are.

Adding talc or marble dust to the gesso is a great way to achieve a more absorbent surface, if that's what you prefer.

I also find it useful to begin with a layer of Kilz or some similar primer, which seals the board. Also, you use less gesso if the board is already white(ish) when you apply the first layer.
Okay thanks you so its affermative to use more water to change consistency

contumacious
04-13-2019, 09:32 AM
You can also use thinning acrylic mediums or something like Floetrol or Thin-X to thin the gesso so it applies more smoothly with greater self leveling without using too much water. The max amount of water to add for those who talk about it for their products seems to be in the 20-25% range. For those who don't mention dilution ratios, I don't go over 20% water, adding some Floetrol or other acrylic thinners if I need it thinner. Check the instructions for whatever you are using.

This is from Golden:

GOLDEN Gesso can be brush, roller, trowel or spray-applied. Dilution of the Gesso is only necessary for spray application, but may be desired for brush or roller applications as well. When diluting with water, we recommend a maximum dilution of 25%. Any mixture within this range offers little risk of cracking or other adverse effects.

And from Sennelier:

White Gesso This universal White Gesso provides a matte surface and exceptional tooth for maximum paint adhesion. It's perfect for painting with both acrylics and oils, on surfaces such as canvas, wood, paper, and board. Use it full strength, or dilute it with water up to 20% to achieve the desired consistency.

WFMartin
04-13-2019, 08:42 PM
I thin my acrylic "Gesso" with water to the consistency of cream. I use Grumbacher 525 Acrylic Gesso, and in its normal state in the container, it is about as viscous as plaster.

I add water to it, and stir with a putty knife, until the mixture runs off the tip of my knife. Not merely "drips", but "runs". When I apply it to my canvas with a sash brush, it is "self-leveling". That means that the dimensional brush strokes flatten a few seconds after having been applied, creating a relatively smooth surface.

Grumbacher 525 Gesso contains, as one of its ingredients, marble dust, or Calcium Carbonate. This creates a substantial tooth to which the subsequent oil paint can adhere. I have used a test sample of Golden Acrylic Gesso once, and I found it MUCH too glossy, and plastic-y, with very little tooth, and it was a difficult surface to sand after it had dried.

The Golden Acrylic Gesso was very similar to normal, acrylic paint, and not very appropriate for use as an underpainting for oil paint, in my experience.

My second choice for an appropriate, acrylic primer would be Liquitex. I found it to have about as much tooth as Grumbacher, and it comes in a more liquid form. However, even in its liquid form, I discovered I still needed to add water in order for it become self-leveling.