Clear Gel-Coat Multiple Layers

[Llunker]

Hey Guys,

Question--

I am wanting to repair a few areas on the boat and I have done so in the past with just one or two layers of Clear Gelcoat on top of polyflake. But in doing so I added a Catalyst like MEKP to the mix so it would cure properly.

My question is If I am covering an area with multiple Clear layers would i need to add the MEKP to each successive layer? or just wait till the last layer and then add the MEKP and cover with wax paper? because each time i use the MEKP i only have about 10-15min working time.

Trying to not use 5 or 6 prevail sprayers if I can avoid it if you know what i mean.

please let me know what you guys do for multiple clear layers of gelcoat.

Thanks

llunker

 

[proshadetree]

Re: Clear Gel-Coat Multiple Layers

This is the repair I need to do to my sidewinder. I have about 3 to 5 lbs of red poly flake I need to get about 2 lbs of silver. I tried 1 seat with duratech/gel and poly flake then duratech/gel. With duratech you do need to use wax unless it is going to sit in the water for extended periods of time. I just needed a thinner mixture as mine was to rough to even sand and buff. I hope someone with more wisdom chimes in. Post some pics of your progress.

 

[Llunker]

Re: Clear Gel-Coat Multiple Layers

I need to lay a base layer that is black--then i am going to do the straw method of applying some flake to the black--let this cure overnight with a maybe a duratec type product --although i have US composites Neutral gel-coat and black color already. Probably just use that...

Then My next step is to apply multiple layers of clear gelcoat so i don't sand into the flake i just applied to the base coat. I am thinking like 5-6 layers of clear and have it raised about 1/32 above the surface and then wet sand it back down.

I just don't want to have to spend $5-7 a pop/layer(5-6 prevail sprayers) of clear with catalyst every layer if I don't have to and end up mixing multiple bottles of prevail sprayers --so yes i can't wait to here from the Pro's on this one.

Thanks guys

Llunker

 

[Bondo]

Re: Clear Gel-Coat Multiple Layers

Ayuh,... If you don't put harder in the lower layers, they won't set up....
That alone will make stacking 'em up, impossible...

I donno what a prevail sprayer is, but Clean it between coatings...
Acetone is a pretty good gun cleaner for poly resins...

 

[oops!]

Re: Clear Gel-Coat Multiple Layers

Hey Guys,

Question--

I am wanting to repair a few areas on the boat and I have done so in the past with just one or two layers of Clear Gelcoat on top of polyflake. But in doing so I added a Catalyst like MEKP to the mix so it would cure properly.

My question is If I am covering an area with multiple Clear layers would i need to add the MEKP to each successive layer? or just wait till the last layer and then add the MEKP and cover with wax paper? because each time i use the MEKP i only have about 10-15min working time.

Trying to not use 5 or 6 prevail sprayers if I can avoid it if you know what i mean.

please let me know what you guys do for multiple clear layers of gelcoat.

Thanks

llunker

uh.....am i missing something here????
we are talking about gellcoat here arent we?

i have not shot flake before so i cant comment on that....however.....
clear gellcoar is still gellcoat....multliple layers wont do you any good....its not like a base coat clear coat.

as bondo said you MUST USE THE MEKP with each coat...
you can use less mekp....down to 1.7 percent for a longer working time.

however....if you do multliple coats.....you have to knock the orange peel down between each coat.
so you have no way to determine the final thickness of the gell coat....you have to be about 35 tho thick, or it will crack (craze)
also ....if the clear you are using is waxed....(i doubt it) but if it is. you have to take off all the wax first or your next layer wont stick !!!....wax is a mold release...so it the stuff goes off on you before you spray the next layer...it iwll stick for a while....till its first good whack.....then it will come apart like it is supposed to do.....

your final layer must be waxed.
you can do two coats with sucess, but multliples???????

the prevail is a good touch up kit.....but it is too small of a nozzle to get a constant spray....you have to thin the gellcoat down for it to spray properly....and that means a tendancy to use more than 10 percent acetone to thin it with ....(unless you use patch aid , but if you are worried about using too many prevail sprayers, then you wont have patch aid).

you can get cheap paint guns at harbour freight.....just get the biggest tip you can find...open er up wide and go for it.

and this my friends.......is why we allways say......read...read...read

 

[oops!]

Re: Clear Gel-Coat Multiple Layers

I donno what a prevail sprayer is, but Clean it between coatings...

a prevail is a small aresol cartridge.....with a straw ! and a glass jar that attaches to the bottom.
it sucks up the paint well and is great for touch ups at 5 bux a kit. the nozzle is very small so you get a fine spray and the aresol round fan.

nozzle is too small for gellcoat, so you have to thin it.

im all exciited today....i get to pick up my new gellcoating gun....lol...the tip is a 3.5...'ell....i can shoot rocks thru it !...lol....im dyin to try it.....im guessing it will keep the orange to a minimum !

 

[Bondo]

Re: Clear Gel-Coat Multiple Layers

a prevail is a small aresol cartridge.....with a straw ! and a glass jar that attaches to the bottom.
it sucks up the paint well and is great for touch ups at 5 bux a kit. the nozzle is very small so you get a fine spray and the aresol round fan.

Ayuh,... Thanks Oops,... I know what they are now,...
They're the little funky lookin' things I chuckle at as I walk by 'em in the handyman section of some boxstores...

 

[Llunker]

Re: Clear Gel-Coat Multiple Layers

also ....if the clear you are using is waxed....(i doubt it) but if it is. you have to take off all the wax first or your next layer wont stick !!!....wax is a mold release...

your final layer must be waxed.
you can do two coats with sucess, but multliples???????

the prevail is a good touch up kit.....but it is too small of a nozzle to get a constant spray....

OOPS,

Yes the products I use come from US composites (http://www.uscomposites.com/polyesters.html)
and they have surface wax in the mix(i know what a mold release agent is). I use the Clear Metalflake Gelcoat Which is a great product and I am only needing to fix small (2in) areas at the most--thats why i use the prevail sprayer and just thin it out a little. I guess what I was trying to get at is do I use the Surface Wax for each successive layer of work?? Your saying If you don't leave off the surface wax the next layer wont stick --if I am understanding you right?

So what you saying is I can make multiple (2 maybe) passes with Gelcoat as long as the surface wax is not mixed in until the last coat correct?

Let me know and thanks for joining in

Llunker

 

[Llunker]

Re: Clear Gel-Coat Multiple Layers

OOPs,

I finally spoke with a Gel-coat expert and the guy shoots gel coat on everyday. He told me this...

1. You can shoot successive layers of gel--but like you said only about 2 maybe 3 --but leans on the side of 2even with the metalflake.

2. To be sure and shoot the base coat of black first without any surfacing wax agent--PERIOD--this sometimes gives off a milky chalk to the spray. Let it dry tacky and apply maybe a heat lamp to make the process move along within say 2-4 hours.

3. Then Spray Clear Gel-coat mixed with the metalflake--again this layers is without any surface wax and let dry to a tacky feeling. DO NOT MESS WITH SANDING THIS LAYER....

4. then Spray additional layers 1 or 2 and still don't use any wax with this mix. The Expert said to use a PVA Mold release agent and allow it to turn green and then it will easily wipe off with water.

5. Then You can start to sand on it and watch carefully that you don't go to deep and get to the flake--compound it out, wax it off with several coats of wax and your done.


Whew--glad i talked to a guy that sprays this stuff for a living....

Thanks to all you guys for your help

llunker

 

[1fishbone]

Re: Clear Gel-Coat Multiple Layers

Glad you got the right advice.

I knew someone that tried that...sprayed two coats of clear with no catalyst, then put the catalyst in and sprayed the last coat, hoping it would 'kick'.
(Trying to save money!)

He came over the next day asking me how long it would take to dry so he could water sand and buff.

What a mess!

 

[oops!]

Re: Clear Gel-Coat Multiple Layers

if the gellcoat you have is waxed,,,,you will have to do the final coat all at once.......

leaving it to get tacky....means the wax will be coming to the surface at that point in the cure......so adding another layer at that time will give you a layer on top of waxed gellcoat.
and it will come off

 

[Llunker]

Re: Clear Gel-Coat Multiple Layers

oops, SORRY i meant to say that the surface wax can be put in it. not that the gel-coat comes that way. I plan on spraying without any wax agents and in the end after the final coat use a PVA mold release agent and then wipe it off with water when i am done.

Will show pics when i am done

 

[ondarvr]

Re: Clear Gel-Coat Multiple Layers

The reason for no wax in the clear is that wax can cloud the clear sometimes, so it may not match the surrounding area.

 

[Yacht Dr.]

Re: Clear Gel-Coat Multiple Layers

OOPs,

I finally spoke with a Gel-coat expert and the guy shoots gel coat on everyday. He told me this...

1. You can shoot successive layers of gel--but like you said only about 2 maybe 3 --but leans on the side of 2even with the metalflake.

2. To be sure and shoot the base coat of black first without any surfacing wax agent--PERIOD--this sometimes gives off a milky chalk to the spray. Let it dry tacky and apply maybe a heat lamp to make the process move along within say 2-4 hours.

3. Then Spray Clear Gel-coat mixed with the metalflake--again this layers is without any surface wax and let dry to a tacky feeling. DO NOT MESS WITH SANDING THIS LAYER....

4. then Spray additional layers 1 or 2 and still don't use any wax with this mix. The Expert said to use a PVA Mold release agent and allow it to turn green and then it will easily wipe off with water.

5. Then You can start to sand on it and watch carefully that you don't go to deep and get to the flake--compound it out, wax it off with several coats of wax and your done.


Whew--glad i talked to a guy that sprays this stuff for a living....

Thanks to all you guys for your help

llunker

Howdies Llunker.. If I may here give you some additional pointers to your list .

" 1. You can shoot successive layers of gel--but like you said only about 2 maybe 3 --but leans on the side of 2even with the metalflake.
"
* Actually you can shoot as many layers of gel that you want for a patch repair *.

"2. To be sure and shoot the base coat of black first without any surfacing wax agent--PERIOD--this sometimes gives off a milky chalk to the spray. Let it dry tacky and apply maybe a heat lamp to make the process move along within say 2-4 hours."

* If black is your basecoat then ya..sounds good..but how do you plan on masking/blending the black without spraying onto the outside clearcoat ? IF you can at all help it..Dont use a heat lamp..use the lamp to heat up the subtrate..but not the applied gel*

"3. Then Spray Clear Gel-coat mixed with the metalflake--again this layers is without any surface wax and let dry to a tacky feeling. DO NOT MESS WITH SANDING THIS LAYER...."

* I would be ready with an Acetone rag to wipe off your clear/metalflake .. for one reason is how much flake you put in..and how much solvent/gel ratio..flake will lay down in gel application to application..you might have to Tweak the amounts of Everything to get it right on ( or even close ). Yup..dont sand your flake layer .

"4. then Spray additional layers 1 or 2 and still don't use any wax with this mix. The Expert said to use a PVA Mold release agent and allow it to turn green and then it will easily wipe off with water. "

* The Expert is right about as minimal additives as possible with clear gel. .. however PVA does not Turn green..its Green right off the bat. Just dont apply the PVA too soon to blow craters in the gel. After your PVA dont touch anything for 24 hours. Wipe off with water is correct.

"5. Then You can start to sand on it and watch carefully that you don't go to deep and get to the flake--compound it out, wax it off with several coats of wax and your done."

* You only want to sand as deep as the lowest level of Gelcoat .. All of the orange peel is Extra stuff and can be safly removed before you buff ( Your real concern is buffing too much too soon ).

There are Many tricks about MetalflakeGel .. and I for one dont have half of the answers othere than it is an art..its tricky and you might experiance a Learning curve . .. If not then Lucky you ...

Peace..

YD.

 

[rjedney]

Re: Clear Gel-Coat Multiple Layers

after reading all of suggestions on your gelcoat, I was thinking when is someone going to talk about release agents? glad they did. good luck

 

[ondarvr]

Re: Clear Gel-Coat Multiple Layers

This may be one of the most useful tips.

"* I would be ready with an Acetone rag to wipe off your clear/metalflake .. for one reason is how much flake you put in..and how much solvent/gel ratio..flake will lay down in gel application to application..you might have to Tweak the amounts of Everything to get it right on ( or even close ) ."


If you need to buy flake, check the actual size and color of the flake on the boat first, there are many different styles and they all give a different look, the amount added changes the look too. Do some test shots with no catalyst until you get the right look, then add catalyst and shoot the repiars. You still need to keep that acetone rag handy though, if it looks bad just wipe it off and try again.

 

[Llunker]

Re: Clear Gel-Coat Multiple Layers

I appreciate all the advice guys--will show picks when i am done.

i guess a bigger question before i even tackle this job is by looking at the pics below does anyone suggest filler first? Then base coat followed my clear/metalflake, then clear?

these are the repairs to be made....

Let me know what you guys think about faring this out and filling first or simply adding base coat will be enough.

 

[ondarvr]

Re: Clear Gel-Coat Multiple Layers

The truth is this being your first attempt at a repair this, and flake being a bugger to make look right, its very possible it will look worse after your finished than it does right now.

Those scratches look to be fairly small in the pics, but it can be hard to tell.

If they are as small as they look I wouldn't spray it, just use a very fine brush or something like a toothpick to put the gel coat in place, and keep that acetone rag handy.

You need to use the same steps, base color, flake layer then clear, but you need very little of each one. Don't over fill it with flake, it needs to be below the surrounding surface so there is room for the clear.

The other option is to find some stickers you like and cover the scratches.

 

[Yacht Dr.]

Re: Clear Gel-Coat Multiple Layers

I wouldnt spray the base/metalflake .. there are other tricks .. Might not be a whole panel spray but .. there are tricks ..

Clear fingernail polish ( for the brush ) .. flake that your going to have to work possibly 3 times in your repairs..before you have it..then clear..clear..build up clear..then blend clear..then sand and polish.

Dont use a gun untill the final stages of clear...dont put your MF on your existing clear...build your color..then highbuild your patch clear..then spray/blend clear..

I dont really know other then that how to do a patch without panelling ..

YD.