Gelcoat Expectations

[JustMrWill]

I am re-gelcoating the bottom of my boat.

The temps have dropped to the 40s-50s. I have an enclosed canopy but it doesn't retain heat well. I may be buying a propane "torpedo" heater to try to keep it in the 60s* for extended periods of time.

I was wondering if I was apply a coat when it is cooler than "ideal" (70*), what can I expect the results to be? Will it bond?
Will it not "lay out" as nice if it is warmer?
Do I just have to give it more time to cure?

I would like to get the bottom done before full winter hits so I can flip the hull and be ready to work on the floor and transom in the spring.

Any suggestions, ideas?

Thanks.
-JMW

 

[neat]

Re: Gelcoat Expectations

It will take longer to cure. Will bond and it will "lay out" as well.

Make sure you have at least 60 until cured. Add more catalyst. Use wax.

 

[JustMrWill]

Re: Gelcoat Expectations

Thanks for the reply.

Now for the "what if"...

If temps were to drop before it is cured, will it have adverse effects?

Also, I was planning on using no-wax for the first couple coats...how do I know that it is cured?

-JMW

 

[klos]

Re: Gelcoat Expectations

What about flamability. Those heaters throw a pretty hot flame dont they?

 

[neat]

Re: Gelcoat Expectations

You can use non-wax gel-coat but you will need to add wax.
Are you keeping it white? If yes, one coat is enough and with your temperatures you will have plenty of time to finish.
When I did mine it was around 90 and I even had lunch in the middle of gel-coating.
As long is tacky you can respray without sanding. At 60' it will be hours.

 

[neat]

Re: Gelcoat Expectations

Why did you put tape on your hull?

 

[JustMrWill]

Re: Gelcoat Expectations

I was thinking of the flamabily problem as well...I may vent the heat in...having the heater located outside...hmmm.

Why did you put tape on your hull?

My plan is to apply multiple coats to the taped off section (it is the area that had the most/worst damage). I figure, if I build it up a bit...it will take another 30 years to rub through again. I am going to go with white no-wax for the base coats. I then was going to apply 1 coat of waxed over the entire bottom. I haven't decided if I am going to try to color match the cream or just do it white. I don't think it will look bad either way...just 2-toned bottom (cream on sides/white on bottom) with nice 1970's orange trim.

-JMW

 

[neat]

Re: Gelcoat Expectations

I would spray only one coat of waxed gelcoat over entire hull.

Mine was really bad too and I did only one coat. That thing is thick.

 

[andy6374]

Re: Gelcoat Expectations

Boatyards lay glass and shoot gelcoat until it freezes. So if it is above 32 you can gelcoat. Just catalyze at 2% and keep a heat lamp on it.

 

[JustMrWill]

Re: Gelcoat Expectations

Hmmmm...

What sprayer did you use? What size nozzle? I was just planning of rolling it on using 1/4" foam roller. I am not worried about it being perfect...I just want to make sure that it bonds well and protects my bottom. Since it was rubbed down to the fiberglass, I wanted to build up a couple coats for "added" protection.

Thanks again for your responses.

-JMW

 

[neat]

Re: Gelcoat Expectations

Roller?
You are looking at long hours of sanding.
I bought the brand new gel-coat gun for under 50 dollars at stickystuffsales.com. Works like charm.

I'm not sure you should use gel-coat to build up. Too much gel-coat is not good either.

Get yourself a gun and be done with entire hull in an hour or two.

 

[neat]

Re: Gelcoat Expectations

also, if you don't finish entire hull before fliping the boat, you are looking at another flip at the spring.

 

[andy6374]

Re: Gelcoat Expectations

Agreed. When all is said and done (ie. after wetsanding and compounding) you'll want a gelcoat of 20-25 mils. Anything thicker will crack when the boat flexes.

You can roll it on but it will have orange peel like a bastard. In this case you will have to roll at least 4-5 coats because you'll thru two coats just hammering down the orange peel.

 

[JustMrWill]

Re: Gelcoat Expectations

Good to know.

Now I have even more to think about and I am running out of above freezing temps.

I am going to look at sprayers....stickystuffsales.com doesn't list prices or any way of ordering online :'( I would like to look at all my options before buying anything. Do you know if "regular" sprayguns (ie - harborfreight) can handle gelcoat? Can I just use a different nozzle or does it have to be a "gelcoat gun".

I have an air compressor but I am gong to need a filter to keep water/crap out of the spray. Will I need to thin the gelcoat to make it work with gun?

I didn't ever think of having the gelcoat "too thick". I was under the impression that "thicker = better". I was also trying to avoid filling some of the scratches\gouges before painting...so...I was going to go thick to help "smooth it out" abit.

Well. I was hoping to be ready to go by this weekend...so I have to make some decissions quickly.

-JMW

 

[neat]

Re: Gelcoat Expectations

Stickystuffsales is owned by Marvin (guy on my project picture), give him a call he will help, you can ask him all kind of question - helped me ALOT. Price is I think 48 dollars. It is great gun. Only thing you need to do is atach compressor and you are on.
It is not hard to do at all.

I don't think you can use just any gun, once again, gel coat is thickened resin.
In my Larson restoration topic you have exact formula for gel-coat, you will just need to add more catalyst, as andy said 2%.

 

[kalla man]

Re: Gelcoat Expectations

I like to catch fish ever think of painting with a two part enamel or urethane. Correct me if im wrong but an enamel is much harder than gel-coat, and you can use your normal paint gun.. just make sure you do the prep work right and try to keep the dust down as much as possible when painting. heat lamps and dry air help too THE PROJECT.......

s99.photobucket.com/albums/l309/kallaman/

 

[JustMrWill]

Re: Gelcoat Expectations

Any pros/cons on gravity feed versus siphon feed sprayers? I am actually now looking for a local store so I can have it ASAP.

I was thinking of a regular sprayer so I can justify the added expense.

-JMW

 

[biggy boy]

Re: Gelcoat Expectations

I just finished gelcoating my transom.
I used a automotive spray gun with a 2 mm nozzle.
I also used two 500 watt quarts flood light aimed at the transom to keep the surface warm. The light worked great. Did not have to heat my whole garage, just the surface i was spraying.
You can get the lights with a stand at Home depot.
You can also get a gun there. the gun cost me 18.00
CDN but I got it a Princess Auto on sale.

Glen

 

[neat]

Re: Gelcoat Expectations

Correct me if im wrong but an enamel is much harder than gel-coat,

What? You are kidding? Right?

 

[ondarvr]

Re: Gelcoat Expectations

Good 2 part PU paints are normally a better choise than re-gelcoating, then just use a keel guard type product to protect the hull.

Gel coat is not formulated to be use at temps below 60* and you will most likely not get a complete cure at the lower temps, it may get hard, but that's different than thoroughly cured. During the re-gel coating process many things can go wrong that will mess up the job and create a great deal off work, I could list them, but I don't have that much time.

You can hide a lot of chips, nicks, scratches and things like that with gel coat, but it's not that hard to do it before using paint. Just a little bit more work before you spray and when your done spraying you just pull the tape and let it get hard, most of the work is done. With gel coat the work just begins when you finish spraying.

It's faster, easier and less costly to use a very good paint than re-gel coating, plus the color and gloss will last much longer.

If you still want to gel coat it, we can continue with what needs to be done to do a good job.