Gelcoat, with or without wax

[Zippys Gelcoat and Fiberglass Repair]

Om making a repair on a stake. I never used gelcoat with wax. Only shot straight from the barrel in the factory. And normal repairs were shot with patch aide added. Will it hurt if u dont use it and shoot the hull.

 

[CarTuner]

The purpose of the wax is to create a barrier between the gelcoat and the oxygen in the air so the gelcoat can fully cure. If you don't use gelcoat with wax, then you'll need to spray or brush on some PVA over the gelcoat after it sets up. This will allow it to fully cure. An alternative to that is to tape a piece of wax paper around the entire gelcoat repair so air doesn't get to it.

 

[Zippys Gelcoat and Fiberglass Repair]

Hmm. So I'm wondering if at the factory when we shot it out of the barrel, did it in fact have wax in it. I've built over 100,000 boats of my career. And never knew anything about wax. I always heated my repair spot up with a heat gun and shot it. About the time I got my gun cleaned she was cured and ready to wipe with acetone 400 600 1000 buff.

 

[Zippys Gelcoat and Fiberglass Repair]

Made me curious enough I got ahold of one of the gelcoaters from Mariah. So I should hear something soon.

 

[CarTuner]

During production of a boat, the gelcoat is the first to be sprayed, and then it's covered with the polyester resin and fiberglass. In this process, it is naturally overcoated and does not come in contact with the air. Hence, it is able to fully cure with no wax needed.

 

[Scherfz1]

Hmm. So I'm wondering if at the factory when we shot it out of the barrel, did it in fact have wax in it. I've built over 100,000 boats of my career. And never knew anything about wax.

thats due to the mold being sprayed then the glass sprayed over that creates that barrier.

 

[Zippys Gelcoat and Fiberglass Repair]

So I can spray the wax gelcoat and it will cure?

 

[Zippys Gelcoat and Fiberglass Repair]

Figured after 20 years I would have that knowledge

 

[kcon]

Isn't the inside of a hull mold waxed before gelcoat is sprayed in it, though typically for ease of removing the hull from the mold?

 

[Scherfz1]

So I can spray the wax gelcoat and it will cure?

you can spray gel coat with wax, just be ready to clean the gun asap because it will trash it, and only spray s much as you can in a 10min period unless its over 70 degrees then you want to start cutting time off of the "working" use of it. also use a gun made for primer, it shoots better, like a 2.4 needle is best. nrthern tol has a good one and for $30, its a green one with regulator on it.

 

[Scherfz1]

Isn't the inside of a hull mold waxed before gelcoat is sprayed in it, though typically for ease of removing the hull from the mold?

they have a releasing agent. i guess you could call it wax, but its not the same to my knowledge

 

[Zippys Gelcoat and Fiberglass Repair]

Kcon not only are they waxed, there are SOLO'd also. Then tape tested. If the tape drags at all on the mold it has to be redone. Cause it will stick.

 

[Woodonglass]

Doing Gelcoat in a Mold and On an exterior hull are Totally different animals. If you're going to shoot the entire hull you should totally grind off ALL the old Gelcoat and get her down to fresh Glass. You Don't use wax in the gelcoat until the final coat. You'll need 4-6 coats. Dump guns are the best for spraying Gelcoat. Temps, Humidity etc all play a vital role in external spraying of Gelcoat. It's significantly more difficult than spraying it in a mold. That's why the majority of boat restorations opt to paint their hulls instead of Re-Gelcoating them. Not saying you can't but if you're not set up properly to do it then your success ratio goes way down.

 

[Zippydoodah]

Well, I called an ole gelcoat friend from our Mariah days. We discussed something. Why are you adding wax on your final coat only? Because when I had a paint spot. I didnt dust it on then wait and dust some more. I piled it on. Sometimes I oiled it on so good it dropped to the floor if ya know what I mean. See we only added about a 1/4 cup of your paint gun can and usually 5-15cc of catalyst. Pending on how fast ya wanted it to kick. Then we got a heat gun, hair drier and finished kickin it off. No wax at all mind you, except that when we were done and the gel was kicked, we got an acetone rag and wipe out cured gelcoat paint spot. So that's why you're saying cover it? Because of the lil stickiness thaat will gum up your paper quicker then you can say the word Mercrusier? Lol. Yup

 

[Zippydoodah]

Doing Gelcoat in a Mold and On an exterior hull are Totally different animals. If you're going to shoot the entire hull you should totally grind off ALL the old Gelcoat and get her down to fresh Glass. You Don't use wax in the gelcoat until the final coat. You'll need 4-6 coats. Dump guns are the best for spraying Gelcoat. Temps, Humidity etc all play a vital role in external spraying of Gelcoat. It's significantly more difficult than spraying it in a mold. That's why the majority of boat restorations opt to paint their hulls instead of Re-Gelcoating them. Not saying you can't but if you're not set up properly to do it then your success ratio goes way down.

Know it's not really. Other then you are gonna milgauge it in the mold then dust the milMark's. I've had it say in the mold no biggy. Wax in the gelcoat. I never heard of such a thing. I wanna know why ya think that being in the open air isnt gonna cure gelcoat when it's a chemical change that occurs. Ya gonna paint it in a vacuum? I dont mean to come across as a smart at all. But I have the knowledge and experience. I know more tricks to repair gelcoat in any form ya hand it to me. From the diamond plate no skid to theswirled. I've repaired it.100xs over. Granted it's been a minute bit itll come back.
and I do love this forum. I love to see how other peeps do it.

 

[Scott Danforth]

So I can spray the wax gelcoat and it will cure?

dont use wax.

if you are going to spray, i suggest to use dura-tech gloss additive and it will flow almost like paint if you get the ratio right, or when you are done spray PVA over the repair, then let it cure and then wash off the PVA

 

[Scherfz1]

dont use wax.
if you are going to spray, i suggest to use dura-tech gloss additive and it will flow almost like paint if you get the ratio right, or when you are done spray PVA over the repair, then let it cure and then wash off the PVA

^^^^^^ right here! And due to how it flows you don’t need as many coats. Also if you are not changing colors, there is no reason to take it down to glass, just blend the surface and feather it for a small area if that’s all your doing. If it’s the whole boat I just make the current gelcoat even (get out all the gouges) then wipe with acetone and spray away.

i don’t use dump guns, that’s for mold spraying where evenness of coats really doesn’t matter

 

[Panoguy]

Why are you adding wax on your final coat only? Because when I had a paint spot. I didnt dust it on then wait and dust some more.

You don't want to use wax (or PVA - my favorite) till the last coat, because as your previously waxed coat begins to set, the wax migrates to the surface - so spraying on top of wax won't properly stick to the previous layer.

I use 2 cheap (Harbor Freight) sprayers for larger areas, 1 for the gel, the other for the PVA - which gets sprayed-on as a final coat. I wait a few days (I know, overkill), and wash-off the PVA with warm water. Works like a charm.

 

[CarTuner]

Is user "Zippydoodah" the same as "Zippys Gelcoat and Fiberglass Repair" (the OP)?

 

[Scott Danforth]

I wouldnt us Harbor Freight guns unless its a one-time shoot and you do not intend to clean the gun

Fiberglass Coatings sells Vapor brand guns, granted much more than you can get them from Amazon or Northern tool.

They are slightly more expensive than the dirt cheap Harbor Freight guns ($35 vs $20), however the harbor freight guns are plastic knobs and if you sit them in acetone, the knobs melt, where the Vapor guns have metal knobs, come off the bat with a 2.3mm tip and come with a cleaning kit (brushes, and a gun wrench) right from the go.