Spraying gelcoat

[George Kornreich]

HI, Jim,Could you give me some hints about spraying gelcoat using the aerosol sprayer. How much hardner do you add, and how much acetone to dilute it? Also, since the gelcoat I'm trying to match is very slightly yellowed (3 years old) compared to the new gelcoat, which is stark white, and I was told to add a bit of gold to it, but I can't find gold colorant. How do you mix pigments to get this gold (?yellow and black?)? Thanks.

 

[R.W.Landau]

styrene

I have never tried an areosol sprayer.Hardener as per the canned directions.Don't use acetone as a thinner. Use styrene. West Marine sells it.Thin till it shoots correctly. To thin it will run like crazy, and to thick it won't come out of the gun.Tinting, That is a trial and error type of thing. Mix to match prior to adding the hardener. You can match color right on the surface you are trying to match. Wipe it off your text match with acetone,then add the hardener and go for it.good luck,r.w.landau

 

[A.L. ("Jim") Willis Pres of ISLAND GIRL PROD.]

Some expert contacts and sources of stuff

Apologies for delay in replying because of holidays and other stuff.I have seen and heard different ways of doing the repairs and I will end by giving you some contacts.Deep gouges are quickly filled with marine epoxy or polyesterfiller. THe area is then wet sanded or compounded back to "orinal color" forming a shallow depression then the gelcoat(after carefulcolor matching) is sprayed on. The gelcoat comes with all info regarding dilution and you use those little propellant pack sprays. One way to get a perfect "blend" is then to put a coat of colored gelcoat with clear (about 50/50) then (wider area 25/75) then 12.5/87.5) etc so that it is impossible to see where the repair actually starts. As with all polyester resins there is a tacky surface where the air interphase occurs and spraying on a coat of ould release allows for this. Although one customer of mine also uses Superwax wiping over- this I have not yet tested for myself.Another way is to do all the repair with gelcoat with thescratch opened up and area sanded/compounded back a bit. THe undiluted gelcoat (thick) is applied by brush inlayers to fill up the scratch and spraying can still be used for blending (otherwise repair usually shows- if not right away eventually as new and old gelcoat change color at different rates). Cellophane film can be used to cure the surface (I've seen a video on this) or mold release again).THen entire area should then be compounded, polished and waxed.There are three sources of gelcoat repair materials and advice than I know (better than chain stores).1. BathTub Express: MTorreyjr@aol.com2. TAP Plastics tech info (they do a brochure and some mail order):conrad@tapplastics.com3. Fiberglass Hawaii 831 476 7464 (mainland contact number)I am learning about this sort of thing in leaps and bounds prior to doing some non-skid and smooth gelcoat repairs on my own boat. We may even sell kits of our own!ThanksJim Willis

 

[R.W.Landau]

more sources

If you are really going to attempt the repair., There are many things to know. Most gelcoats are unwaxed. This is a material in the resin that surfaces during curing of polyester resins to cure the outer surface of the resin. Unwaxed resin leaves the air exposed surface tacky. With gel coat there are a few ways of curing the surface without a waxed product. One is to spray a pva release agent on it after it takes initial set.This is a water soluable material that should just wash off with water after curing. Another is to apply a slip sheet or celofane sheet over the resined area to eliminate air from contacting the surface.Test your wrap first to make sure that the gelcoat does not eat it away and contaminate the surface.Fibreglass Coating Inc. Has good products and an informitive catalog in thier "how to" section.email: sales@fgci.comFibre Glast is another company that has a web site that can be helpful. They have many sections on Fiberglass terms, basic repairs, resin info, glass cloth etc.You would want to look under "Composite Repair" towards the end to see info on gelcoat and spraying.The West System guides give info on gelcoat also.hope this is enough info for now.r.w.landau

 

[Zsolt Regenyi]

Gelhandling

I am a new owner of a oday22. She is 23 years old.What can I do with the small cracks on deck lamination. The hull is o.k.Buttom need paint work.Thanks in advanceZsolt Regenyi