i was wondering if anyone was succesful with infusion bagging system,
as far as resin ratio it would be the best for a super light/strong board.
the boat yard in my area is using this tech with great success.
bert? anyone?
Personally I have not used this tech, but I have done some research. Very Interesting stuff. I thought this page was helpful regarding the subject. I like the little project kit to get familiar with the process.
http://www.fibreglast.com/showproducts-category-Vacuum%20Infusion-20.html
In theory, it sounds great… dry lay up, no rush and calculated resin usage… but I think where most boat builders are using this technique with success is only for glassing the outermost layer of a denser (read non-absorbing) hull.
When constructing sandwhiches - I don’t see anyway to infuse the inner glass layer without completely soaking your EPS core… seems impossible to soak an inner layer of glass that’s vacuum sandwiched between your main core and sandwich core. If somebody has an idea of how to do infuse resin efficiently for both the inner and outer layers, I’d also be interested to hear it… LeeDD, did windsurfers experiment with any of these techniques with success?
cheers, Brennan
you wanna go straight to the top dont you louis …
brennan ! you interested out of interest or you thinking about setting something up ???
i checked out that link , it blew me away that its basically an industry now , my first foray was in 96 , i called it reverse vacumn moulding …
in one way or another ive had to make most of that stuff there selling …
like they said at there site , infusion should only be attempted by someone with previous vacumn bagging and open moulding experience …
im not going to talk on this subject …
this is basically the stuff id want to get paid for …
because your gonna blow alot of time and money , to learn to do something thats already being done , and customisable as well , not in a mould as you would presume …
even tho ive worked a moulded version that pops em out like cheap sunnies or some other cheap pop out product …
i was going to make a cheeky comment , but im not even going to make dual meaning suggestive hints…
im off the subject …
regards
BERT
Louis,
I’ve seen more by others and done a bit of infusion myself. Most of what I have seen in person by others is in the boating industry, but I have also seen aerospace infusion done in heated autoclaves.
For infusion you need super high vacuum with no air introduced into the part from your bag or seal. And if a core is involved it would have to be closed cell and able to handle the pressure needed for infusion.
Go look at the vacuum figures Bert posted about the pvc/eps board he just made. He’d have made a pancake of that eps with the near -100kpa vacuum pressure needed for infusion. It “might” be possible to do the outside glass job with infusion. Maybe if you could get resins with viscosity lower than what I am aware of, you could lower the vacuum pressure (so as to not suck the life out of the eps) than what would be needed with typical 400cps to 250cps infusion resins. Darcy’s Law. You need to use resins with super low viscosity. Much development has been done with resins for infusion over the last few years. Fabrics and flow-mediums which facillitate resin flow. Check with your local composites distributor.
Now if you have a couple of molds, which you could easily make yourself, used a closed cell core that could handle the pressure, you could make two shells which could then be joined like that hollow board with the eps ribs that was shown here recently, infusing both sides of the core material in one process.
Many in the composites industry say that certain types of pre-pregs and resin films that are being developed are the future.
I’m not an expert, I’m just saying what I think I know to be true. I’m sure there are things out there which only people that work for a company like Boeing know about.
Check out some of the past and present patents from as far back as the 50s
thanks G
i will try a few ideas andlet you know how it goes…
Louis,
Here is a website that has brief details of composites and processes that you might find interesting: http://www.netcomposites.com/education.asp?sequence=65
hi Bert,
I’m just interested in trying new things, but I don’t see the advantage of infusion here unless your putting together a high speed production facility and using ultrafast cure epoxy… Like you’ve demonstrated on your ongoing post, calculated and efficient resin usage is possible without infusion or prepregs - all you need is a decent scale.
I’m still just getting comfortable with my bagging set-up… working on my own ‘Bert inspired creation’ in my limited free time. The transition has been a little slow but very rewarding. Before I started, I was trying to completely redesign a 'spring’board based on composite wing design - only putting extra reiforcement where it is absolutely critical to distribute loading and dictate flex. Your current designs have already tackled so many problems facing standard surfboard design; domed decks, non-flexing stringers, etc. Thanks for everything!
For anyone else reading this, follow Bert’s ongoing post and order the “Vacuum Bag Board Building” video by Canadian (I think) windsurfer Tom Sullivan. In fact, I may have accidentally ordered a second video - so if anyone’s interested, PM me. That will get your head spinning with possiblities. Too many doors, not enough time!!!
http://www.victoriavideo.com/board.shtml
Cheers! Brennan
edit: That video is only $35 (not $50) at fiberglasssupply.com… better just to order from there, I won’t be around for the next week or so.