Dear Moderator. I am trying to find a way to get a smoother surface for portrait painting in oils as I’m regularly encountering lumps and bumps in my lead oil primed linen. I’ve tried gently abrading the raw linen, pre sizing, with a pumice stone, which did help, but now find the acrylic size I’ve applied is quite rough to the touch. I’m using Liquitex matte medium diluted 1:1 with water and plan to apply 2 coats. I know about the need for a size to penetrate the fabric rather than act as a distinct layer. I’m not trying to achaieve a glassy surface just a smooth one. By the way, I intend to glue the painting to a panel once it’s finished. I’m concerned that using sandpaper or pumice stone on the size will actually remove the size to the point hat it no longer performs its function of sealing the canvas. Is this a legitimate concern and if so what can I do about it?
Thanks Brian!
Good question and your feelings are well founded. Sanding will cut through the size on the uppermost fibers and leave them capable of absorbing ground or paint layers. This is no worry, though. It is best to apply a couple of thin layers of size and lightly sand the first, or first and second if you are applying three very thing size applications (two is generally preferable). Just make sure that you do not sand the final size application.
This is the way in which I have always sized painting substrates. It is very difficult to remove the fuzz and errant threads that protrude from the surface of unsized fabric. The size hardens the fuzz/fibers so that they are more easily abraded and brushed away before the final application of size.