Is primer nessesary?

[_JMFR]

After many hours, i FINNALY finished sanding down and smoothing out a cab i'm building. i was debating if i should prime it before i rolled the paint on. Any advice?


* I realize i should maybe move this to the woodworking section.....but the Main board gets the most action! 

[Blanka]

1 prime layer and 2-3 final layers. Light sanding after every layer, except the last off course. If it is MDF/Particle board, clean the surface first with Aceton 
Final layer paint naked wearing undies and a hairnet, between some wet bedsheets (to prevent dust).
Water paint should be painted horizontal, alkyd paint is best done vertical.

[_JMFR]

1 prime layer and 2-3 final layers. Light sanding after every layer, except the last off course. If it is MDF/Particle board, clean the surface first with Aceton 

Whats a good primer to use??

[Blanka]

Same solution as the final paint, so both water based or both non water based. Sigma Satin U2 is very good stuff.

[_JMFR]

where can this sigma satin be found?

[Blanka]

Maybe this forum should introduce some region flags. EU, Americas, Pacific, Asia
Guess Sigma Satin is available in every serious paint shop in Europe, whereas North America may not use that brand/name at all.

[SavannahLion]

If it is MDF/Particle board, clean the surface first with Aceton 

Acetone? Really? I've read that Acetone can cause wood particles to shrink as it displaces the moisture then evaporates. Would you still end up with a kind of "reversed" wood expansion kind of effect as some wood fibers shrink more than others?

[Level42]

Final layer paint naked wearing undies and a hairnet, between some wet bedsheets (to prevent dust).

??

Pics !!!!!!! 

[Blanka]

There is also special MDF cleaner solution. But I guess it is something similar to aceton.

[ghettodish]

For MDF I wouldn't use anything except a vacuum and tack cloth to clean the dust prior to priming. MDF is too absorbent. Cleaners, including plain water, can make the surface swell. Some solvents will actually dissolve the adhesives that hold MDF together, or at least make it swell. Wet MDF dries from the outside in...when the top layer cures it actually locks in the moisture underneath.

Use a quick-dry solvent- or lacquer-based primer. On the West coast of the US the Zinsser products are popular:
http://www.zinsser.com/subcat.asp?CategoryID=1

B-I-N and Cover Stain are quick-drying and sandable. If buying it in gallons make sure to have it tinted first. Only tint it to half-formula of your top coat: gray primer for black paint, pink primer for red paint, etc. Two or three rattle-cans also work just fine if you spray even coats.

Make sure to wrap yourself in wet sheets and put undies on your head.