Do you prime new filler??

I recently completed the filler on my brand new canvas and its been 6 weeks. Can I paint right over that or should I apply a coat of primer first? Thanks for any advice.

 

I use primer. You could do either.

 

I prefer using primer first.

 

Sand the filler, apply primer and sand that before paint. You may want to apply two coats of primer depending on how smooth it turns out. Good luck & have fun

 

I've canvassed over 30 canoes (it's just a hobby - honest!), but have only used a primer on the last 4 canoes - for all the others I just started painting on the filled canvas.

Which ever direction you go you'll want to sand down the filled (and cured) canvas. This is like sanding down sandpaper as a filled canvas surface is a little like cement. I believe what makes the surface so rough is little cotton fibers coated with 'cement' sticking up from the surface. I've found that if you apply the paint directly without a primer then it'll take at least two coats of paint, sanding between coats, to get a surface that feels & looks smooth. And the paints I use are noted for providing a hard surface, so again it's like sanding sandpaper.

What's nice about a primer is that it sands easily (it's a little soft) and does on a little thicker than paint. This makes sanding down to a nice smooth surface much easier, and being thicker it can hide slight canvassing imperfections plus cover those fibers that stick out. Also on the plus side is that primer is generally cheaper than paint.

On the minus side is that you've got a less hard surface between the canvas and the paint, so I wonder if this makes the painted surface more susceptible to deep scratching that gets down to the (whitish colored) primer.

 

As others have stated, you must sand the filler first. The question is "how much". If you want a very smooth substrate for your paint and expect to achieve that by sanding the filler, you will most likely break through and expose the canvas weave in places. So, the trick is to sand just enough, but not too much. If you achieve this, you will be left with a surface that is not perfectly smooth and full of imperfections. Thus the use of a high build primer which gets applied and then sanded off to fill these imperfections. This may require multiple primer applications and removal depending again on what your expectations are for the final finish. Some are satisfied with a paint job that shows lots of imperfections and some expect a yacht-like finish.

By-the-way, a high gloss paint highlights imperfections in the filler whereas a semi-gloss paint is much more forgiving.

Have fun!

 

Sand paint; sand paint; sand paint; sand paint; sand paint; sand paint; etc. until you are so disgusted that you quit!!!!!!!!!

 

I think Gil forgot to add in one more sandpaint!