every time i get on a kick and all excited about something bert has already done it or is doing it… i ordered an infusion “starter kit” a few weeks back and have been planing on attending this class…
http://www.abaris.com/resin.htm
at least i know i am not heading in the wrong direction…
JJP
Bert,
For the heck of it, try pulling vacuum on your part and put it under a heat lamp for a few hours before you infuse. If the air goes away, moisture was probably the culprit. Also, on carbon fiber laminates we use a thin c-veil, this helps disperse air out of the carbon. Maybe this would help.
JJP, Ask Abaris if this class will be taught by Andre Cocquyt. He occasionally teaches his infusion class at Abaris. If not, I would check out Andre’s website for class dates and locations. www.grpguru.com. He is an incredible teacher and has made just about every mistake there is and knows how to teach you not to make the same mistake.
Sluggo
i know what your aiming at tho . i use a whole range of resin systems with different hardnesses and flex patterns, what i use on the bottom of my boards is different to what i use on the outside of the deck and different again to what i use on the inside and yet still different to what i use on the rails , 4 resin systems in one board , plus different fabrics and other materials in certain spots …
color me crazy…but how do you mix (pardon the pun) this with VI…not that im interested in doing just wondering out loud…
But Bert, you say you’ve been doing infusion on all your boards since 98? Why are you asking these types of questions of someone you hardly know on a public forum?
Cocguyts dvd has been out for over two years now where have you surfboard industry people been? For many that’s old stuff now. What Sluggos saying is on the dvd. Watch it.
so all i need is $500 to buy the dvd? gosh, bert must be stupid wasting all that time with trial and error. Imagine spending thousands of dollars and countless hours of your life when all it took was $500… after i buy the dvd i think i’ll run out and buy some prozac and a turbo tunnel…
speaking out of my ass, i would bet there is a big difference between infusion of say 18oz tri ax. and mat, that is engineered for infusion, that is going to be gel coated and infusion of say 2oz that you want clear and defect free…
hey meecrafy…my guess is one or two resins for bagging on the skins… one type for bagging on the rails… one type for the outer glass… again speaking out of…
slugo thanks for the advise… i also saw his list of classes and was thinking about his dvd course to start… i am going to try to make some fins with the test kit…
maybe it will even help slow my current rate of production to less then a board a month…
Don’t be lead down the wrong path… Do you want an exact matrix volume or do you want to fill every void… Prepreg is controlled…and where you want it… Various terms to send you down the wrong path…RTM, VARTM, VRTM, VARI, VIP, RTM, TERTM, RARTM, RIRM, CRTM, CIRTM, RLI, RFI, SCRIMP, UVRTM
thanks for the heads up… i’ll keep that in mind… there are soooooo many options… now could you explain “Do you want an exact matrix volume or do you want to fill every void.” a bit more… i am not a pro composit man just a guy with a large garage…
what do you build???
Not that these acronyms are not good…for…other things
sluggo …
na thats definatly not it …
in my old production set up , we had a giant oven that held a dozen boards …
been right through the baking process , thinking just that , that it could be moisture , even moisture in the timber , or gas from the timber , so many variations on baking , doing different combos of timing , heat before resin , heat resin before board , adjust pressure through stages , some of these combos made it even worse , in each case it gave a bit more insight into the real problem …
i still firmly believe its the resin itself causing the problem …
because different resins can have the same reaction but way worse …
we still use the same process , but ive come to live with that slightly dry look …
i have a question for greg …
at what point in the curing of the resin will shrinkage start to occur??
and at that stage will any volatiles be released ???
also oceanrider …
you never know where or who might have the answer your looking for …
doing this type of stuff is just a logical off shoot of vacuum bagging …
the reality is my first foray into these techniques was 96 ,i even had to build special machines to make certain materials more suitable for the processes … but it took a few more years before i had the systems worked out and the confidence to do a whole board …
its really only in the last few years ive even heard some of the acronyms you mention …
i had my own names for the techniques i was using …2 years hey ???
so much of the stuff being promoted is a hoax …
they want you to use techniques that consume materials , the crew promoting the videos are the same guys with all the goodies to sell when you come back all excited …
i think you can possibly see now why i would consider the surfboard industry stuck in the dark ages …ive always said no one had a clue about what i was really up to , well i guess some have some clues at least now …
sluggo , thats why i asked you the original question , if your doing clear cosmetic style work …
because i think what im trying to achieve is in the grey area and pushing the limits of what rt can deliver with any consistent quality …
still trying new stuff everyday , just been a while since any major breakthroughs …
i think greg could have the next piece of the puzzle …
regards
BERT
now could you explain “Do you want an exact matrix volume or do you want to fill every void.”
cannot water make its way through eps…closed cell is used in an RTM process…even balsa absorbs more resin under especially the vacuum versions of these processes Is there an eps that won’t suck…not that I’m aware of hail to the maker of the new core
also oceanrider …
you never know where or who might have the answer your looking for …
A way to completely and I mean completely seal the eps prior to opening the gate…or your doing the shell in a seperate process away from the eps…then your infusing the shell and not the board
where did you get those assumptions from ??? weigh up all the variables and principles of physics and you see the complete opposite is the reality …
if someone even gets close , i will pitch in …
regards
BERT
Bert,
Most everything happens at the point of peak exotherm and after. Volitiles are definately released at this stage and shrinkage begins just after as you begin to cool. This is where there are real advantages to curing in an oven. Also if you can match your ramp up to the speed of your cure you may eliminate some problems. This could be something to consider … maybe your ramp up is exceeding the speed of your cure which is causing a drain or allowing some other movement by lowering viscosity at a point. To some extent when using elevated cure you can get away from many of the uncontroled room temp issues like exotherm and some shrinkage and in the end get better HDT and less interlaminate tension. But in the little work of this nature I’ve done I did find ramp up speed to be important.
bare wood…ghost infusion…getting the inside infused…keeping the outside dry…wow…
call me ignorant but why the drama of vi on the inside when one can get close using simpler techniques…i can get 1:1 ratios without vi using simple techniques…especially on the inside…from what i’ve read vi has mostly ease of mfg bennies, mainly cleanlyness…but only if you’ve worked out all the kinks…too many hoops for this guy
The magic number is 60:40 - fiber/resin…
The goal is no air (traditional methods)
ps. Bert, for some reason I see a cave full of bats stretching down to take a sip out of a pool on the cave floor… Glug, glug, glug. Nah, maybe it’s a micro vibrational unit designed to break up that swirling liquid flow front and keep the resin sheet moving through nice and even. OR maybe the inner cloth is pre-wetted to seal the air in the eps and the infusion is done mainly on the outside through a good flow medium?
yeah daddio i’ve seen that ratio referenced before but its very application dependent…for foam cored surfboards you also need a good seal and nice costmetic surface finish so while 60:40 may give best strength to weight, it may not be the best ratio for the other critical criterion…i mean you still gotta hotcoat (and maybe gloss coat) and that’s blowing the ratio right out of the water…additionally, i can accept a few ounces more weight in the finished product particularly when the product comes from my garage…there are so many different ways to skin the cat…i tend to choose simpler garage based techniques that yield excellent results…eventually you reach a point of diminishing returns…a lot of extra work for minimal gain…im sure bert would disagree tho…when i get to 5.5lb with excellent durability and performance i’ll let everyone know…assuming there’s interest…getting closer…btw, garage is looking pretty sweet now…even the wife’s impressed
i agree there meecrafty …
the effort you go through for just a few grams less , sometimes seems hardly worth it …
im more driven by the competition needs of my team surfers , where every gram means the difference between a 9.7 winning ride or a 9.3 losing ride …
daddio , i would love to send you a pic of how i do it …
even just a pic of one piece of the puzzle is all it would take …
its all about flow and porosity …
but of coarse i wouldnt make it that easy …
but yea once your in the sandwich composite field , the next steps for improvement are way smaller …
from a surfboard production point of view , it slows the process down , but delivers a stronger lighter article , which has more value and offsets the extra costs and time …
make more cheaper disposables , or less , more expensive longer lasting boards …
if i had to weigh up a standard sandwich with a hand layed outer glass job , or the full infused sandwich composite version …
i would say keep doing handlay ups till you can vacuum bag in your sleep …
then take the next step if you feel the need …
but for what its worth , it is only the smallest gain in weight saving from the average sandwich and you loose quality in the finished article …
but that doesnt worry my team surfers , if i have to strangle the life out of there boards for every last drop of resin …
i wouldnt recomend it to anyone who hasnt been vac bagging for years …
just to much pain …
regards
BERT
If you think maybe your bulk resin is absorbing moisture from the atmosphere, how about using a nitrogen gas purge? This creates a dry gas blanket in your container.
I originally used it to extend the life of my polyurethane products and have since also used it with epoxy just to be on the safe side. I mold under heat and 100psi pressure. I still sometimes get gas off bubbles. Could be from the mold release too. Who knows. I expect a certain amount of waste in any production I’ve ever been involved in.
Purge stuff comes in a spray can. Mark
found this using google…
Epoxies
Epoxies are less prone to moisture pick up during cure. Some hardener components however are moisture sensitive and require care in storage and handling. Storage is recommended in containers purged with Nitrogen and all epoxies should be de-aired under vacuum for best results.
Surface bubbles are most likely caused by one or more of the following:
- Excessive air introduced during mixing.
- Improper surface tension preventing bubbles from self-releasing.
- Index of thixotrophy too high.
Fix:
- Mix slowly to avoid air entrapment.
- Warm the mix if possible to reduce the viscosity.
- Spray surface with mould release (usually works)
- Pour slowly in one corner and let the material rise pushing the air ahead of it.
- Select a different product for the application.