Best for Applying Gelcoat, Epoxy etc. as a Paint

[E350]

I would like to become a master craftsman at applying gelcoat, epoxy, etc. as Paint.
If I am going to put the time, effort and heartache into learning the proper procedures and technique, I don't want to be handicapped by poor guns.

@elkmaster101 @ondarvr @bntii @LMB @Blueknarr @Scott Danforth @Mr Efficiency and others

What do you use? What do you recommend?

I have seen these two guns noted but I am willing to use any gun recommended.

https://www.amazon.com/Fibre-Glast-...lcoat+cup+gun&qid=1560860859&s=gateway&sr=8-2

https://www.amazon.com/Accuspray-16...m+gelcoat+gun&qid=1560860910&s=gateway&sr=8-2


Finally, thank you @elkmaster101 for your gift of time to put together these two excellent threads:

gelcoating the whole boat down to the waterline https://www.boatdesign.net/threads/gelcoating-the-whole-boat-down-to-the-waterline.61694/

It was a lot of work for you to do, and it truly is a gift of love.

 

[waikikin]

Hi,

The first gun is as simple as you can get and good for spraying gelcoat into molds for contact molding- you would be disappointed with the "off the gun" finish.

The second 3M guns look good though I haven't tried them yet, heard some good about them. Generally to get any ind of "off the gun " finish without too much finish wor you will need an additive such as Duratech.
Ondarvr has the "word" on all this...

Jeff.

 

[djamson]

Adding Duratec is a good method also. This additive thins the gelcoat just right for easy spraying.

 

[E350]

Or, switch to a 3M spray gun, no clean up is required. All the plastic parts are cheap, the disposable parts cost less than the acetone required to clean them.

@ondarvr there may be more than two types of 3M Accuspray guns. One as depicted above, has the extra tube to the cup which the others don't have. Do you use or like or recommend the Accuspray gun for applying gelcoat like paint and if so which one(s)? Or do you prefer another gun for this process?

waikinin and djamson I don't know how to use the forum to issue thanks. My guess is that I don't have enough posts to do that yet. But thank you!

 

[ondarvr]

Equipment and techniques used depend on what it is you plan to do with the gel coat you’re spraying.

In a mold is a bit different than for refinishing a large surface, which might be different than a smaller surface area.

Of these two guns, the 3M accuspray is much better, it would be my choice for most small jobs over just about anything else.

If you need to spray larger surfaces, like boats larger than about 20’, then going to a pressure pot system will make life much easier.

 

[E350]

My mold experience is limited to hand laying light weight white water kayaks without gel coat.

I plan to refurbish hulls on various watercraft, not to build new from a mold.

I did not know about pressure pots:

pressure pot gelcoat spray system - Yahoo Video Search Results https://video.search.yahoo.com/search/video?fr=mcafee&p=pressure+pot+gelcoat+spray+system#id=3&vid=7500d3d6315732bf6277a275ccd53e4d&action=click

I will go with the 3M Accuspray gun with the tube (HGP):

https://www.amazon.com/3M-16054-PPS...JZMHZHHNDTC&psc=1&refRID=G06KN7A6GJZMHZHHNDTC

I like the idea of being able to use the 3M throw away cups on my existing HLVP paint spray gun with this adapter:

https://www.amazon.com/gp/product/B000N9RWTK/ref=ox_sc_act_title_4?smid=ATVPDKIKX0DER&th=1

What tip size do you recommend I start with?

And unless you guys have other suggestions, I will just start on a plywood board for practice.

Anymore suggestions or comments?

Thank you for the site and for the gift of your knowledge and experience. It is recognized and appreciated.

 

[ondarvr]

You need a large tip.

I think 2mm is the largest tip, or at least it was last time we bought some.

 

[KD8NPB]

Binks 2100 w/ 68SS (2.8mm) tip + 2 qt pressure pot is good for most jobs. You'll need a fairly stout compressor in any case, most spray systems will require 12 cfm+ @ 40 psi to get gelcoat moving and atomized properly.

You can purchase plastic liners for the pot to cut down on solvent use. Remember to cut off your atomizing air when you're flushing the hoses and siphon tube out to reduce emissions. I usually spray the gun in to a closed top 5gal pail to capture the waste solvent and reduce splashback / mess, then disassemble and clean the nozzle / needle.

I do not recommend the ES Mfg cup gun for "out-of-mold" use, it atomizes like crap and will give a very rough finish. It's good for spraying in to a mold though. The 3m Accuspray HGP system works well, but it's a little expensive to run. You're new though, so you're likely to destroy fluid nozzles because of gellated material, so maybe it's a good option for you.

I recently purchased an MVP Pro Rider 22:1 w/ ATG3500 spraygun that will be available to rent from South Carolina soon. It only requires 6 cfm @ 100 psi. It is an airless air assisted system with slave-driven catalyst pump, and externally atomized catalyst. It will rent with both premium spray tips for gelcoat and fluid impingement tips for resin.
Pro Rider Gelcoat System - Magnum Venus Products https://www.mvpind.com/product/prorider-gelcoat-system/
They're the best way to do it, but expect to spend about $4400 new. No catalyzed material is inside the gun or lines, so there's no rush to clean anything when you're done.