Question on Types of Nozzles for Gelcoat Guns?

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#1

I just ordered a Gelcoat gun and it comes with a 3/16" nozzle. They also sell other sizes of nozzles. The other sizes are 5/32" for resins and gelcoats, 7/32" for gelcoats, and 9/32" for gelcoats with flake. Which is the best nozzle for the job. My goal is to get a class A finish on all my parts. I am really just concentrating on Motorcycle parts like fairings and such. So the sizes vary from entire bodykits to heel guards.

#2

I think either the 3/16" or the 5/16" is fine.

#3

Thanks Evan.

#4

can an hvlp spray gun with a larger needle/tip be used as a gelcoat gun?

#5

yes you can. I do anyway.

#6

You can use a HPLV gun, but you have to thin out the gelcoat so much that you would have to continue going over it. That togther with the cleaning in between will slow your work down. If you can buy a gelcoat gun you can spray your gelcoat with the proper nozzle and get it down with the proper thickness. You can use the HPLV to shoot top coats, it won’t leve an orange peal on top. The gelcoat gun does leave an orange peel look to it but since your spraying it into a mold where it will be layed with material it doesn’t matter as much.

#7

what’s the proper way of applying epoxy gel coat? have to be brushed on?

#8

Yes the epoxy has to be brushed on.

#9

my experience with epoxy surface coats isn’t too extensive(made a couple parts in school)… We used it both on the mold and the piece we made… when you’re making a cf part, how is the gel coat used… or is it only used on the molds?

#10

The epoxy tooling gelcoat is used for the mold and any other epoxy surface coat can be used to make parts. There isn’t any clear epoxy surface coat that I am aware of for making parts. The Clear Epoxy Top Coat that I sell comes close, but it’s more of a top coat that you apply afterward.

#11

so I want to just layup the cf/laminating resin in the prepped mold then?

in your vacuum infusion demo, you said your mold was gel coated… is this just a to ensure the finish on the mold, and doesn’t in any way get transfered to part you’re pulling?

#12

No the gelcoat sticks to the laminate when you pull the part out of the mold. So when the part is cured and removed from the mold, it already has a clear finish coat to it. I don’t need to do anything else besides trimming the part and maybe sand & polish

#13

I take it you’re using a polyester gel coat for that purpose then? are you also using a polyester resin?

#14

The gelcoat and resin are both polyester in the demonstration video.

#15

ok… I guess I need to get out of the always use epoxy mind set that we get stuff with at school

#16

Quick run down on the procedure:

  1. Spray gelcoat into mold. HOW LONG DO YOU WAIT BEFORE YOU GO TO THE NEXT STEP.

  2. brush in clear resin.

  3. Lay up carbon fibre. HOW MANY LAYERS OF CARBON DO YOU LAYUP FOR SOMETHING LIKE A MOTORCYCLE FAIRING, IF YOU WANT IT TO BE KINDA FLEXABLE.

  4. Take out all airbubbles with brush.

#17

Hold on, what video?

#18

Hold on, what video?[/quote]
http://www.icancomposites.com/forum/viewtopic.php?t=203

#19
#20

Thanks for the info, it really got things in perspective for me. Also looks like I won’t be able to make this weekend. :frowning: