To prime or not to prime

travisluman · 06-30-2009, 12:56 PM

Hey guys,

I'm preping an old 78 hull to spray white gell within a week or so. My question is should I spray a primer on before to fill in small imperfections? The boat is red and I am going white. If i should prime, what is a good primer for this type of application?

glassdave · 06-30-2009, 04:49 PM

you are using gel and not paint? If gel then don't primer anything. Do all your repairs with a filler like 3M's vinylester fairing filler or similar. Finish to about 150-180 grit and go right to gel, the gel fills a multitude of sins. Will you be using a wax additive or Duratech?

travisluman · 06-30-2009, 09:33 PM

I'm going to be using Duratech. I was told I could use Duratech surfacing primer. Do you not recomend using it before spraying the gel?

glassdave · 06-30-2009, 10:19 PM

yes you could just spot prime if you need to do additional fairing to any bodywork done on the boat. I rarely use it, the gel usually fills in most stuff. I had the exact twin to your boat in my shop last winter for exactly what your doing

racinfever · 06-30-2009, 11:13 PM

Dave
When & why is Duratec used instead of just adding surface agent ?

Audiofn · 07-01-2009, 06:50 AM

Quote:

Originally Posted by racinfever

Dave
When & why is Duratec used instead of just adding surface agent ?

From what I remember it gives you a harder top "shell" on the gell coat. It also shines a little better. Other then that very little advantage. It has been a while for me so maybe Dave has more to add.

glassdave · 07-01-2009, 07:04 AM

i usually use Duratec for just my final finish. If i need to really straighten out a surface i'll lay on the bulk of the gel using a dump gun and waxing additive and aggresivly block that down with 80-180. After the surface is nice and true I'll come back with a few coats of gel thinned with Duratec. This is something to consider when changing color as the Duratec really thins out the colors ability to hide. You can still get it to hide spraying only once but you have to back up the amount of Duratech you add to the gel. It may not flow as well and you'll have more sanding to do but can eliminate the recoat.

travisluman · 07-01-2009, 11:22 AM

Thanks for the help Dave. Do you happen to have any pics of the boat you did that was like mine? Also, I have never sprayed gel before but have painted a few cars. I will be using a gravity feed gun as i was told it will work with the Duratech additive. Any tips on spraying?

glassdave · 07-01-2009, 01:32 PM

I will see if i can dig them up. Spraying gel is pretty easy just keep laying it on and get the biggest tip you can for your gun. I would use less then the recommended ratio by Duratec. Cut that in half and do a test spray. Add more if needed.

MF · 07-01-2009, 01:45 PM

Hi, i take the opportunity to ask a few questions to the glass guru !
Never sprayed gelcoat before, is it a lot harder ti spray than awl grip or poliurethanes paints ?
What are the stages for painting with gelcoat and do you need a stronger compressor to do the job ??