Gelcoat application

http://stores.infinityfrp.com/-strse-124/spray-gun-gel-coat/Detail.bok

Cheap?
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http://stores.infinityfrp.com/-strse-SPRAY-GUNS/Categories.bok


Will get a professional catalyst mix at gun system. The unevenness of the polycon spray, requiring more resin to fill spaces is reason enough not to use it.

 

Hi Mr idkfa ( and others );the suggested gypsum gun + pressure pot looks perfectly OK and very reasonably priced but it says that the noozle is 2.5 mm and have read that 2.5 is not enough for gelcoat without reducing it, even in the very same page of Infinityfrp they simultaneously claim that 2.5 mm is perfect for gelcoat and also 4.55 mm so what is correct ?? please check those two links ( one of them the one you gave of the gypsum/gelcoat pressure pot + gun kit)

http://stores.infinityfrp.com/-strse-124/spray-gun-gel-coat/Detail.bok

http://stores.infinityfrp.com/-strse-403/Resin-Spray-Gun-Gel/Detail.bok


I have been searching for quite along time for a HVLP spray gun with a large 4-5 mm diameter noozle in the belief that such a large diameter was needed in order to avoid reducing the gelcoat and the only ones I have found are intended for Gypsum or painting signs on roads.

So is it appropiate the 2.5 mm noozle or not ?? is it better to use a 4.5 mm noozle or not ?

Because I only want to buy once and not make a purchasing mistake that could lead to laborious and contly repairs.

 

http://www.northerntool.com/shop/tools/product_200320615_200320615

I'm actually spraying with a 1.4mm nozzle, no thinning, home made pressure pot. Like you was weary of pressure pots and thought the polycon would be better for its simplicity.

I don't have the experience of the others but 4.5 is needed for gravity flow, 2.5 at pressure is large enough IMHO.

The REAL problem though is batch size, mine is large enough for my smaller pieces, but I've made arrangements to have the main hull (only 20ft) done at a shop with professional equipment, I would not try to multi batch a single pressure pot, that's the best advice I can give you. So we're back to where we started.

 

Tip size varies with the size of the part you are spraying and the exact gel coat you are using, plus most people have a couple of different tips so they can fine tune the gun each time for exactly what they plan to spray.

Buy a gun, get a couple of different tips, then practice a little.

In the larger pressure pots, like the one linked, you can place a paper or plastic tub into the pressure pot to hold the gel coat, this keeps it clean and allows you to change batches and refill it rapidly.

 

I'll second that. Orange peel on steroids, in my experience.

 

Might come down to product & process, I've put plenty of FGI Aquabar white thru mine that went down pretty flat - very slight waver but am plenty happy wjth it & chalk & cheese in comparison to brush or roller, if Jigger struggles with it, it's small change in equipment, I've done panels around 12M x 1.5M using the Polycon, . Regards from Jeff.

 

It seems, that what Idkfa says is the key to my question about tip size, under pressure, 2.5 mm equals a larger diameter needed when gravity fed.

 

I agree, better than brush and roller. However, a Binks 18 or a De Vilbiss JGA 502 with a two quart remote would be upgrades IMHO. If you have help catalizing resin and a powerful compressor I think you could shoot Gel coat all day long, and should be flatter. The HVLP guns, even the very cheap imports, seem to have a fair reputation, here, if set up right, again maybe someone to catalize and help. I did push polyester worms out of my two quart remote lines once when falling behind schedule on my own; just barely saved the equipment, but it was a smallish compressor which forced me to slow down and not shoot continuous.