Applying gel coat.. 101

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CaptainD101

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hey there gents,
I understand the application process as I have done plenty of research, Im going to make this sweet and simple by listing my procedure and equipment. Just looking for any advice from there. Keep in mind Im not looking for a completely professional job, just average results. Got the boat for dirt cheap just looking to make it pretty again

white ferro gelcoat w/ wax
hardener
acetone for thinning, cleaning
spray gun hvlp with 1.5mm nozzle gravity fed? ( will this work with the gelcoat thinned a little bit, or still to small)
6hp 20gal compressor w/ water separator

Was planning to spray just a couple coats of gel coat then be done with it. My buddies paint job with the same stuff came out pretty good. He just sprayed two coats inside and out didn't even sand it or wax. There was a little orange peel but couldn't barely tell. Didnt use the pva or clear additives, just gelcoat. Looks good today from last year
 

Woodonglass

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Re: Applying gel coat.. 101

I would think a 1.5 mm tip is a little small. 2.5 is the norm. 20 gal compressor will be cycling a LOT due to lack of volume. How big is your hull?
 

GT1000000

Rear Admiral
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Re: Applying gel coat.. 101

Not 100% sure, but I think the wax should only be added to the final coat?

Do a test panel to get familiar with the equipment and the material...
 

CaptainD101

Petty Officer 3rd Class
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Re: Applying gel coat.. 101

I charged the compressor up and got a good amount of spraying holding the gun constantly before it kicked in. well w/ wax im sure will work cant be that big of a diff.?

yea the guy at the body shop said its a little small but may do the job when its thinned out. guess ill have to try it.

now I have one concern I live in a residential neighborhood and was planning to spray in the drive way, at least the top side. Will this stink up the whole street or its not to bad after its done. Also how far will the overspray travel. just basic spraying concerns. thanks
 

proshadetree

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Re: Applying gel coat.. 101

I would up the tip size on that gun. My 2.5 will not lay out a good coat without excessive thinning.
 

Woodonglass

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Re: Applying gel coat.. 101

Gelcoat sets up in about 15 mins after you mix it. You must have the gun emptied and cleaned before that or it is permanently ruined. You should not spray without the boat tented to contain the overspray. I gurantee that if you thin the gelcoat enuf to get it to spray out of a 1.5 mm tip it will run really bad. So you have never sprayed or used gelcoat and you think there's not that much of a "Diff" between the two. I'd say you REALLY need to do some searching and studying here on the forum before you attempt this project or you will be in for some BIG surprises.
 

Friscoboater

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Re: Applying gel coat.. 101

My next resto I plan of spraying it, and I do believe you are not really supposed to thin it much at all. Just get a bigger tip. I have shot lots of catalyzed paints before, so be ready to clean up them minute you are done. It will kick in your gun, and you are toast.
 

CaptainD101

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Re: Applying gel coat.. 101

sprayed half the inside this mourning, and pretty sure im done with my first gun (lol). Might be able to save it, but I lost the paint adjustment screw when I pulled the needle out to clean and miss placed it...F@#$#@$%

Well I learned when you mix batches to use a new cup every time, I was mixing the second batch in the same cup and was clumps from stirring the side. gun got clogged, I emptying back in the paint cut then ran it through a strainer and got most of the clumps out.

With 1.5 mm tip took me forever to clear a whole cup of paint. Deffinatley hitting the harbour freight tonight for a larger tip gun. This stuff really dries quick once its sprayed.
 

Woodonglass

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Re: Applying gel coat.. 101

I hope you did not use the waxed gelcoat. You only add wax to the last coat. You should not thin more than 15%. If you did what you said you were going to do in your first post then the boat is pretty much messed up and will be a total mess. JMHO.:rolleyes: This is not how you apply Gelcoat. I do not think HF has guns with tips large enuf unless you get the HVLP suction Pot Gun not the gravity feed type.
 

CaptainD101

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Re: Applying gel coat.. 101

well I did use the waxed gelcoat. Looks good to me. Like i said im not looking for completely professional look. It seems to have bonded well, and was drying in a matter of minutes. Im no expert painter but im sure its going to stick on there well and give me a pretty decent result. Next to a professional job im sure theres no comparison, but for a driveway job i think it will do.

my friend used the exact same paint w/ wax and still looks great from last season. Just applied a few coats and that was it, So im going to do the same.... actually I was talking to him last night and he said he rolled the floor and the bottom of the boat, and just sprayer the outside walls to get a nice shiny look. I dont want to roll it on
 

Woodonglass

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Re: Applying gel coat.. 101

If this is a One Step Gelcoat then you may be ok. But you must sand with 180 grit between coats to give the next coat something to bite into. the Wax will prevent a good bond. You should attempt to get the gelcoat to a thickness of 20 mils. That's a little thicker than a penney.
 

CaptainD101

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Re: Applying gel coat.. 101

yes im pretty much trying to just do a one step gel coat. I suppose Im basically painting with gelcoat. I really like how its come out so far, when this stuff dries its solid as a rock and wont scratch like paint does. I had to do a few batchs to get it to spray right out of the gun, Im at about 25% thinned with acetone with a 1.4mm gun, could use more spray but getting this job done. I was thinking a gal was going to be enough for the whole boat, but im definitely going to need one more.

I mixed a really hot batch on one of my first sprays and the gun was shot. I brought it back to Harbour Freight even without the receipt and she let my buy the $10 2 year replacement and gave me a new gun (the $35 hvlp), so when im done spraying im going to go get another one .. and another.. GET THE $10 WARRANTY YOU CANT BEAT IT, they have replaced my gokart motor 4 times when it blows.

http://i41.photobucket.com/albums/e274/DDENIS1000/IMG_0154.jpg
http://i41.photobucket.com/albums/e274/DDENIS1000/IMG_0155.jpg
 

sweet addiction

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Re: Applying gel coat.. 101

Be careful on how "hot" you mix the batches. Too much m.e.k.(hardener) and you will start to degrade the gel coat. It may "look" fine but the integrity is gone. Yes the gel coat containing wax is only for the final or single coat applications. To do any other gel work you will need a "laminating" type of gel coat.
 

Woodonglass

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Re: Applying gel coat.. 101

Again, just so you are aware. No Gelcoat mfg recommends thinning gelcoat more than 15%. It will damage the chemical curing characteristics and also the bonding. And once again, since it has wax in it the mfg states that you must sand between coats to remove the wax and allow the next layer to bond to the previous. This also goes for any overlapping areas if you are only applying one coat. I can understand them replacing a Blown engine if it MFG Defect but if you ran it withou oil, would they replace it? Using a gun that is not capable of the job and then not cleaning it properly and expecting them to replace it is, IMHO, not what a warranty is all about. But, if you feel comfortable doing it and they don't check it for user abuse then go for it.
 

CaptainD101

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Re: Applying gel coat.. 101

yep I took your suggestion the other day I sanded the area I was going to be overlapping, just scuffed it up with some 80grit. When I went back after it dried it was stuck on there, and wasn't scraping off when I went across with a penny. I will let you guys know the final results. But so far so good.

Harbour Freight by my house replaces all the tools or equipment with the warranty no matter what happens, I ask them at purchase from several different employees and was always told to bring it back no matter what and they will exchange it for a new one. The motor once blew from low oil, I busted a driveshaft once, and before I sold it went and picked up another with 0 hours for quick sale. Call it what you want but they replaced them with no questions asked every time, literally no questions asked.
 

Cadwelder

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Re: Applying gel coat.. 101

You keep to saying painting with gelcoat, dude, gelcoat is NOT paint, it's a far cry from it. And the application for both are miles apart....

Also heed Woody's advice on the thinning, if you're thinning at 25% you're way past a good job. The chemical properties of the gelcoat are gone at 25%. I spray gelcoat nearly everyday now and don't thin at all, get you a dump gun for $100 bucks from US Composites and you're good to go. Catalize at 1.5% and you'll have about 15minutes (at 70 degrees) to shoot it all out of your gun. But it only takes about 4 minutes to empty a quart gun, so you're fine...

One problem I had when first starting learning was mixing the gelcoat with the MEKP, just a little stirring isn't good enough. I use a small paint mixer on my battery drill and the results are far better, gets a much better mix of the harder with the gelcoat.

Once you're gelcoat has cured (not dried), then you're ready for hours of sanding and buffing, but you'll have a great long lasting finish.

Hint: (you'd have been better off to have just sanded her down good and painted it, espically since you said you're not looking for a professional job)

CW
 

Woodonglass

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Re: Applying gel coat.. 101

That's all well and good, but you are still thinning it WAY to much. I just hope it lasts as long as you're hoping. Time will tell.
 

River_Lizard

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Jan 17, 2012
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Re: Applying gel coat.. 101

I mixed a really hot batch on one of my first sprays and the gun was shot. I brought it back to Harbour Freight even without the receipt and she let my buy the $10 2 year replacement and gave me a new gun (the $35 hvlp), so when im done spraying im going to go get another one .. and another.. GET THE $10 WARRANTY YOU CANT BEAT IT, they have replaced my gokart motor 4 times when it blows.

I'm trying to understand where this falls under the right and wrong of a person's action. Let me understand...you (your action) ruin a spray gun and then take it back to get covered under a warranty? Not a manufacturer's defect but a buyer's neglect...and you don't see a problem with that?
Do you realize we all pay for that in cost markups to cover that expense??
 

Woodonglass

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Re: Applying gel coat.. 101

Thank you for that ^^^^ I was trying to figure out a way to say it, and you did it PERFECTLY!!!! Just because THEY will does NOT make it RIGHT!!!!! Like Momma always said..."How would you like it...If they did the same thing to you!!!!":facepalm:
 

CaptainD101

Petty Officer 3rd Class
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Jun 15, 2010
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Re: Applying gel coat.. 101

lol.. Like i said she gave me a new one no questions asked, I was thinking the same thing, but would you say no to another gun for a $10 warranty or buy it for $35 again... the only point im trying to get across is if the employee offers me a better deal im going to take it. River lizard I dont have to even intentionally ruin the gun I can just go in and say its not spraying right and they will give me another. you can word it however you want, but when im told they will replace no matter what happens to the gun or other item im going to use it slightly to my advantage.

well honestly im redoing this boat to sell it right in summer time to make a profit, this is my first full restore usually just hull and motor swapping, but the price was so cheap for the hull and trailer I decided to go for it. So i wont be having it for to long . Im sure it will hold well for a few years and give the boat a like new condition when I sell.
 
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