can i vacuum bag polyester resin

is there any problem’s with vac bagging polyester resin whilst it’s wet and going off?

i read somewhere it could be ? i suppose most people are using epoxy?

also what’s good for wrapping over the wet rail’s when your bagging?

Yes, it can be easily bagged, but there are some challenges  you will face.  Put down a peel ply, then a breather, and bag, that’s it simply put, but I left out some of the craftier parts.

i read there’s prob’s with the curing heat under vacuum? as it goes quick an produce’s reasonable amount’s of heat?

any tip’s on the rail’s?

He jb,

G-rat is right, he left out some parts.  For example, condensing an explosive gas mixture (styrene fumes), and releasing it about six inches from an ignition point (your pumps motor).  Sort of like a bong hit of gasoline, and blowing it onto an open flame.

so what are we saying dont do it??? or how can i get around it? come on guy’s give me some advice for safety!!! i assume epoxy is ok cos it dont produce as much styrene when it vent’s??

Sure you can.  Use UV Poly Resin.   Bag it and then walk the whole thing out into the sunlight.

surely there will still be the issue of fume’s when under vacuum?

do you mean disconnect the vac line to bring out side? cos the resin will kick quick in the sun the bag wont have to hold it for long i guess?

does any one get decent result’s bagging with polyester?

With regard to Polyester Resin that is catalyzed; yes there are fumes as a result of the chemical reaction.  With regard to UV Polyester;  there is only a light smell.   No chemical reaction resulting in toxic fumes. ..  You can vacum bag UV if you can walk your blank, bag, pump etc. out into sunlight.  But pay No attention to me.  If you are worried about it scrap the Poly and use Epoxy. 


Sounds like fun!!!

marky miller you know nothing about making surfboards- zero.  What self promoting bag of misinformation you put forth,  

Where do you come up with this bong hits of gasoline garbage.  I bet you don’t even know how to hang a door, and you have to go down to the day labor guys to help you, ha ha hah.

What I left out was the polymerization rates change under vacuum with polyester resins, but your miscreant mind doesn’t seem, to understand anything I talk about.  Like how much pounds to pull, depending on the thickness of the laminate, and what you can get away with on the substrate, presuming it is foam.  Jb’s question is very broad.  You wouldn’t last an hour working with me.  Go practice planing your 2x4’s.

jb, If your going to go to the trouble, and expense to bag something why are you using polyester?

Hi G-rat

Never had a claim to know much about building surfboards in comparison to an expert such as yourself.  How about if you bump up my build threads, I’ve done three or four.  Feel free to tear them apart.  How would a pro do it differently?  I’m always open to criticism.  Makes me more proficient.

Since you mentioned door hanging, my website home page has an entry that I custom hung.  Feel free to point out anything you see.  Could you also review the other web pages?  Everything there I designed and built.  (except the Framing pages.  A couple of shots were designed by others.)  My website is at the bottom of my post.

As for the vacuum question, most uf us on Swaylock’s are Garage builders.  Fire hazards in someone’s home, with their families in danger is a real concern.  Sorry to ruffle your feathers, but I stand behind my comments.  Same with the danger in removing the blade guard on a skill saw, but that was another thread.

Not sure what self promoting you are talking about.  I don’t sell boards, so nothing there.  For the construction business, I did do a free Kitchen design for a Sway’s member, but since I didn’t charge for it, I wouldn’t call that promotion either.

And you are correct, I wouldn’t last an hour working for you.  Off to my day job now.  Thanks, it has been fun.


I asked myself the same question… 

Resin cost,  I presume…

 Aside from the pump and running it electrically , the bagging materials can be very inexpensive, or quite expensive for the pro materials, depends on your intent as well as pocket book pain threshold…

I suppose he’d still get a  better, tighter laminate than non-bagged polyester with better cloth to resin counts… But the poly is the weak link in this tech…


I’d love to see some of your vaccum bagged builds G-rat…

I’m  currently working on 4 composite builds right now,  all at various early stages of build…I want to document the construction of  them now I that I finally own a good digital camera…

Come on, You show us yours, and I’ll show you mine…Ha.Ha…

you guys have answered my question’s an some that were’nt even written down!!

it’s partly price and partly, an idea!

i can get cheap poly an cheap eps, an im working on way’s to use them together!



barrel’s of resin shooting through the roof . like rocket’s. is not fun, so i have been told!

The ways to use them together have already been worked out.EPS foam,glass and hotcoat with EPOXY.

POLYURETHANE foam,glass with POLYESTER resin.I would not waste my time trying to vacuum bag polyester resin.If you vacum bag polyester resin over eps foam please video and put it up here for our entertainment.

If you want to use polyester and still vacuum bag it but are worried about the danger of fumes and the pump you could always use a hand pump such as the one used on here > They vacuum form maple veneers with it and it almost reaches a full vacuum. I think it would be good enough for what you are making. I thinl it would actually be cheaper than buying a good pump too

If you find a way to combine EPS foam and Poly resin without spending a lot of time sealing the foam, please let us know.

If you want to have some fun, you can try glassing an eps blank with UV resin and then getting the resin to go off ASAP. If you can get the shell done before the foam melts you should end up with a hollow shell. I’ve found that UV poly resin will turn EPS foam into cotton candy like fiber over time. A very different result from exotherm melting of foam.

Kiterider, I really like sharing the information without drawing attention to the real me.  Ghettorat is a joke name.  Because surfboards, sailboards or paddleboards, normally aren’t made in the best parts of town.  And board builders really have to survive on the leftovers, and since I am sharing trade secrets, kind-of. Nonetheless, its a pretty safe bet to say I have seen more than most people around here.  I try to share real stuff, that matters about board making, and take my word this isn’t even scratching the surface of what I know.  Still its comical that I wont share my name.  I just don’t care, plus if you haven’t noticed some of the folks around here aint right.  Still got to say while you have attacked me in the past, I harbor no ill will toward you, and it may make you feel superior that I admit I no almost nothing about kiteboarding.  Its also pretty safe to assume that the 14’ race boards I mentioned earlier will be bagged, with carbon fiber, and I could not afford to buy my own shapes, but that is not my problem, and i don’t have to pay for them.

i dont know why people are getting upset, an there’s also no point in having a go at each other!, i just joined this so i can talk to peep’s like me, an we can SHARE information, everyone has different way’s of doing the same job, and everyone has there own particular, skill set’s and process’s.

This FORUM has been great to gain info, it may have saved me blowing my self up so far!!

I will aim to give back what i have gained, as such, although vac bagging is a new area for me. Like you guy’s price’s of material’s for me are crazy at the mo so im looking at keeping the price down, and not use so much consumable vac bag equipment.

Im sure it’s nothing new here but im going to try bubble wrap for my reusable breather membrane. And i have found some push fit 6mm fitting’s, so they should be easy to connect/ disconnect, and are very light weight, etc. Am using a pump that’s older than me so hope it will be up to the job!

so will let you know what happen’s in my experiment’s. Dont worry im not talking about wet lamination, with poly/ eps! although it can be handy when you want the foam to dissapear.

any one tryed the sealing thing for eps?

Thanks for the reply G.R.

I would still like to see some of your shapes, as would many more here I’m sure… Perhaps logo side down or hidden… I harbor no ill will towards you either…

 I was  just stiring up the shit with a few of my posts directed at you…  That’s something I’ll refrain from doing from  now on…  When I  read what I’ve written, those type of “digs” sounds stupid and petty… My bad…

   What pressure are you bagging that sup at?       There are some cool cheap load spreading materials that let you up the pressure on laminates over bare foam … Won’t let you go as high as core-cell or even bamboo veneer over foam, but increase the safety factor… Pre-cured carbon top sheet inlays  are also a good way to increase pressure and not crush the foam…

  In many ways  (flexibility, simplicity, weight, cosmetics,cost  etc.) kite-board construction is  inferior  to surfboard construction at this stage of development…  That’s why I spend so much time here soaking up the info…