Bumpy Texture on Boards

[sflagirl]

Hi,

I have just made an annoying discovery: the boards that I have prepared with gesso have a bumpy texture to them. And I have quite a few!

I sanded them initially, but not between each layer and I think that is what the problem is.

My question is-if I sand them now [with three + layers of gesso] and then paint another layer, will there be problems later on?

Thanks for any advice that you can provide.

[Elwell]

Hi,

I have just made an annoying discovery: the boards that I have prepared with gesso have a bumpy texture to them. And I have quite a few!

I sanded them initially, but not between each layer and I think that is what the problem is.

My question is-if I sand them now [with three + layers of gesso] and then paint another layer, will there be problems later on?

Thanks for any advice that you can provide.

Illustration board or hardboard? glue and chalk gesso or acrylic?
Sanding and adding more layers shouldn't be a problem, but exactly how to go about it will depend on your answers.

[dbclemons]

Hi,

I have just made an annoying discovery: the boards that I have prepared with gesso have a bumpy texture to them. And I have quite a few!

I sanded them initially, but not between each layer and I think that is what the problem is.

My question is-if I sand them now [with three + layers of gesso] and then paint another layer, will there be problems later on?

Thanks for any advice that you can provide.

I'm assuming this is acrylic gesso? There shouldn't even be problems now, since the only real reason for sanding is to get a smooth surface. It's a final sanding that usually does the trick. I don't bother sanding between layers myself, and don't have problems afterwards. When applying your coats, did you brush each layer at different angles from the previous (one layer horizontal, the next vertical, diagonal, etc. ?) This helps smooth out the brush lines. Also, there's a wet-dry sand paper that's good for sanding gesso since it doesn't gum up like regular sand paper.

-David

[sflagirl]

yes, this is acrylic gesso. i usually buy the top grade and this time i kind of skimped and bought the one at dick blick. but, when i inspected the boards, the ones that were done with the better gesso did it too, just not as bad and the texture feels better-more 'rubbery'.

i do sand them before i start to gesso. i dilute the first coat a little. and then the subsequent coats are done without water. i do trade off-horizontal, vertical, horizontal, etc. i have never done the diagonal, i am going to try that.

i think my biggest mistake is just the sanding. i am going to give them a really good sand now. i am glad that they can still be used-i have been stocking up and the thought of starting over was pretty horrible.

thanks again!!!

[Elwell]

yes, this is acrylic gesso. i usually buy the top grade and this time i kind of skimped and bought the one at dick blick. but, when i inspected the boards, the ones that were done with the better gesso did it too, just not as bad and the texture feels better-more 'rubbery'.

i do sand them before i start to gesso. i dilute the first coat a little. and then the subsequent coats are done without water. i do trade off-horizontal, vertical, horizontal, etc. i have never done the diagonal, i am going to try that.

i think my biggest mistake is just the sanding. i am going to give them a really good sand now. i am glad that they can still be used-i have been stocking up and the thought of starting over was pretty horrible.

thanks again!!!
Use wet/dry sandpaper with plenty of water, going from a medium to a medium/fine grit. Those foam sanding blocks also work well. If the final surface is too smooth and shiny for your tastes, give it one last coat of very diluted gesso amd leave that one unsanded.

[dbclemons]

If you feel a bit daring, next time try laying down your coats with a flat plastic tool like an unused credit card or a plastic spatula. Troweling it on this way avoides the brush marks, but you need to be careful not to gouge the gesso. It leaves a thinnner layer which is fine, and you can then blend it out with a damp brush. You will probably find that it won't even need sanding.

-David