good surface finish with vacuum Infusion Process

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#1

I have a question, in the VIP it is very hard to achieve a high gloss, no-print gelcoat. Somebody says that this is not yet possible with VIP.

Now I like to know any suggestions about:

We are in process to make a 30 ft hull with vacuum infusion but we hope to have a good surface finish (off course).

My idea is that if we will first gelcoat the hull mold and hand lay up with the same vinyl ester and two surface veil layers followed by two 300 gr/m2 chopped or continuous strand mat and wait the complete gel coat and resin polymerization for a three days or more, than we will starting the regular infusion, I think we could have a better surface without or less gelcoat print. What do You think? Please any suggestion welcome.

Please advice

Luigi

#2

First of all…how good is your mold? Is your mold glossy? What tooling gel coat are you using? What resin are you using? If you plan on building an epoxy mold…use a vinyl ester gel coat with the proper tie coat and you should be able to get a good high gloss on the mold. Once you have a good high gloss on the mold, it is possible to get a high gloss on the part. With print-through…my best answer would be to use a good surface veil.

#3

Dear Sir, our mold is extremely glossy, build in vinyl ester resin with tooling gel coat (isophtalic polyester resin based) because in Thailand cannot find vinyl ester gel coat. We will use two surface veil and two 300 gr/m2 mat in hand ;lay up previous infusion, but we are afraid that print out will come during the infusion process due to exotherm heat of the infusion stack. Please leave any suggestion about.
Thanks

#4

well I dont know what resin is offered in thailand, but here in the U.S alot of us use the Reichold Hydrex 100 which is a Vinyl Ester Resin with a relatively low exotherm…prob 175-200 F. Try giving that a try. I infused a 10 ft. boat hull before but never a 30 ft + one. Also …you might want to check ur mold release system too… try calling up Chemlease…they have a 3- step semi permanent mold release system Their PMR-90 is designed specifically for infusion and gives superior gloss finish.

#5

are you infusing the whole boat at once or in steps are you using a fiber glass stringer or wood the boat factory i worked at was working on infusing 30 ft parts it took them 3 years before they started infusion production they had alot of problems geting resin under divinicyl (spelling?) i never worked with them on infusion at the time i thought they were crazy for spending that kind of $ but they have it in production now and wish i would have worked with them i missed out on a great learning experiance i do know that they did use vinyl ester resin from ashland in production i would not think the wax system or gell coat would be any diferent than hand lay i do know also that the chop gun a first layer before infusion set up

#6

you should get the DVD infusion guru. He goes through and infuses a boat and shows what materials and what equipment was needed. Very good DVD!

#7

problems… gotta link?

#8

http://www.vat19.com/gurudvds/

#9

Or. you could contact diab and airtech. I was at an infusion in Detroit where they did a 34 foot hull and a 34 foot deck.

They did the insusion directly against a sprayed gelcoat.

#10

I got three different CD included the DVD infusion guru. These are all good helper expecially to training the staff. We done one hour daily training for three months and we used the DVD as visual demonstration. But Sirs, not any of these resource talk about gelcoat cosmetics problem.

#11

I am not sure how they do their infusion, I never bought the dvd from guru since it was over $80 when I wanted to learn. I saw the infusion of the boat hull and learned on my own after that. My supplier treid to help me, but he wasn’t much help since he only knoew boat infusion and I wanted to do Carbon fiber. I sprayed duratech directly into the mold and when it cured enough to be slightly tacky to the feel but not enough to stick to your finger. I placed my fabric in the mold, after all the fabric was in, i applied peel ply, flow media, and then I pulled a vacuum, sealed all the leaks, and then released the resin into the mold keeping my resin level below the mold.
let it fill, and then lower the vacuum pressure allow it to gel well enough as to not disturb the fabric, and then pull the bag, flow media and peel ply. and allow it to cure the remainder of the way.

#12

ha,you make it sound so easy :lol:

#13

Well it is for us now!

L.O.L.
good comment!

#14

that’s all i gotta do… that’s easy (in some monty python voice i can’t think of for sure right now)

#15

once you get it right the first time it seems easy

#16

That first time you get it right and understand why you got it wrong it does seem easy.
By the way damn good explanation of the infusion process doogie, you helped me get it right, thankyou. I think the most important things to remember are NO leaks, leaks kill the process, understand vac line positioning especially on complicated parts and understand your chosen resin flow characteristics. Get it all correct and you`ll know almost immediately you open that first resin line that your going to have a successful part :slight_smile:

Print through as i understand it can mean weave or cloth showing through the gelcoat or dry spot print from resin lines, i havn`t had the problem of weave print through because my gelcoat (clear) was thick enough and hard enough before i started infusion and dryspot print can be eliminated if you have to infuse on the part by careful use of barriers under your resin lines, tees etc.

Baz