Vacumn forming & Sandwich construction

tape hose support base to bag ...




your pump ...
realistically , the pump will be the biggest investment , i got this little baby 11 or 12 years ago and it still cost me $1,000.00 back then ,, this one is called an ov4 , its a carbon vaned pump , it clears 4 cubic meters an hour , you could vacumn 2 boards at once with this as long as your bags were in mint condition , it can pull up to - 75 kpa or 11 psi ...i remember at the time , that paying a grand for this baby felt like a big step , coz prior to this i was using vacumn cleaners , which were between 30 and 50 dollars from the secondhand shop .. they would burn out and i would get another one ...
one day a vacumn cleaner burnt out while i was doing a mal , the job was beyond salvation , i was already using my wifes cleaner coz mine had burnt out days earlier ,,i couldnt get a replacement at short notice,,,, after 2 blowouts in quick succession and losing a whole board , the costs started to justify them selves ...i had one previous vacumn cleaner last me 3 years , they do work, but i had built a frame to exagerate the vacumn and was using it mainly for doing timber decks on polyester boards back then , when i made the switch to production epoxy sandwich , a vacumn cleaner just didnt handle being on for such long periods ....

like others have said on other threads ,, look around , things like milking pumps , refridgerator vac pumps , other stuff does work thats not so expensive ,, also the cost of new pumps has come down in the last decade as well , like digital watches ,,, once 300 dollars , now 2 dollars ....



heres the production baby .....in its own outbuilding outside , i have a 40 m3 per hour pump , connected via a pipe through the wall to an evacuation chamber , then 5 seperate outlets , tapped and gauged ....
back when i was running some serious production , i had a t piece off each outlet , combined with a process where we could bag 2 boards back to back in one bag , i could vacumn up to 16 boards at one time ,, 1 valve was left solo for other purposes , which probably wont get discussed for a few years , till some of you guys start experimenting ....

you can see the top gauge is my tank pressure , that will determine the most pressure you can run for any job ....ive got 3 jobs running now while i took this photo ,, one at - 20 kpa another at - 40 kpa and the last equalling tank pressure at - 80 kpa ,,,,
the pump can pull - 100 kpa , but when your running 3 jobs and 2 are being purposely bled for resin transfer , it starts to drain the system a bit ....
its an oil vaned pump , the main pump is immersed in oil so air cant escape back through the system ....

ive connected the spare hose to a permanent bag on top of the tank , mainly to show the bag ....

its solid plastic , the stuff they use for annexes and outdoor restaurants , its been plastic welded to seal it , a bag can be up to $200.00 ...
in the early days i used bagging tube , taped off the ends , i usually got about 10 vac jobs out of one bag , it was cheap only about 10 cents a meter ..
but there was time involved in making a new bag every 5 boards , retaping and changing connections ,, then there was the drama of chasing holes in the bags when they got worn before you got frustrated and changed the bag ...
so if your doing more , it ends being way more economical to have permanent bags ,, one of my first permanent bags is still running , its probably done 900 maybe 1000 vac jobs and still going strong ...ok
i will leave it there for today ...
the good stuff comes tommorow ....




are you sure this is a surfboard factory???

regards
BERT

next is a pic of the rocker bed , a piece of flexible sheeting , but not to flexible , my contour mat taped to the middle of the sheeting ,,, and a piece of 3mm divinycell with dry glass laying on it....


now ive mixed up 150 grams of epoxy , ive rolled up and folded my glass into a neat package , then placed it in my tub and wet it through ....

the divinicell is sitting on the rocker bed/flexible sheet/contour mat , ive got the glass and strained it out so its quite dry then i rolled it out and flatten it down with a sweegee


one more page ...

this is old sckool for me now , thats why i dont mind passing it on , but these techniques , really opened the doors to me ,in the sense of leading me to another level ...so i figure it should get some of you guys out there up to speed and at least competitive with moulded imports ...
i get frustrated when i see millions getting pumped into the development of new technologies , coz the guys spending the money have no idea how far behind they really are ...im not knocking development , but from my perspective i see grand claims getting made through the media , i think to myself , "man thats gonna cost them " i see dodgy product getting released and unsuspecting buyers lap it up only to get burnt ...anyway ill leave that one there .. ive got plenty to say on that subject ,, that could be another thread ....

yea john , there is so many possibilities with vac forming , and completly customisable ....
before i continue ill answer your questions glenn ....

yep 1/8 h 80 bottom , 1/2 h 60 rails ....
that glass is 2 oz e , this board will be for me so im milking it all the way , if it was a guy off the street it would be 4 oz e ,,, not that i would build a board this way for someone ,, this is purely a swaylocks dedicated project , to familiarise everyone with vacumn forming ....

as far as foam v balsa rails for stiffness ,,,,
your deck and bottom skins do most of the work as far as stiffness , thats why i havent done wood rails im trying to make it flexier to counteract the thicker sandwich ....plus i dont want to show how i do my rails ...
i will lose spring tho , by not using wood , thats why its going to be a super small wave groveler designed to be surfed flat in soft mush ...
you can do all of that stuff you mentioned , it will depend on the overall thickness of your rails and board in general as to how much or little flex/stiffness you want or desire ....by moving layers around you can really achieve so many different characteristics in performance and not even have to change the shape ...
thats why i want more people to understand sandwich construction , so then finnally crew will understand why my shapes work so well even tho they shouldnt if appraised by conventional wisdom ...


ok back to the subject ,,, now youll notice the whole job in the bag , bag taped for a seal and the rail pieces sitting wide and high nothing is where its supposed to be ...

ok i cheated a bit , i didnt use the little pump ,,,,my big pump was running and i had a spare connection , so i hooked it up to the radiator hose on the bag ...now you can see the bag has pulled vacumn , everything is tight and pressed against everything else , the bag has formed the rails tightly against the blank , the blank and rails are being pressed tightly against the wet d cell im running about -30 kpa which is 300 grams of pressure for every cm2 , so this job being about 2 meters x half a meter ,, means its recieving about 3 tons of weight spread evenly over the job holding everything in place ....

heres the whole job being pressed , you see the rocker bed doing its job ,, in the first place the rocker is computer designed , your off cut simply becomes the bed to ensure you have the correct rocker ,,, even if you dont get your foam cumputer hotwired , its important to keep the offcut in good condition if your home hotwiring ...its also possible to use the opposite offcut ,the deck one , if you use that one you can customshape a bottom before adding your d cell , itll take a bit more work to get your rails on cleanly , plus you have to be very careful when bagging the deck , coz you cant use the bottom bed in the same manner ...


its funny ive got all this stuff in the back ground i dont want seen , so if you see the same backgrounds from different angles its because im moving blanks around in the background as coverups , coz im working in my vac form room , if you saw some of the background stuff and these basic principles , im sure a few crew in similar fields would put 2 and 2 together ....dont want any snakes and frogs looking in ,,, hehe .....

continued,,,,

traditionally , its near on impossible to shape a piece of 3/4 lb eps , its just like shaping a floppy sponge , but now you have something rigid with the h60 rails and bottom already pressed on ...


ive fully scooped out the deck ,under my feet would be barely an inch thick ,,, this contruction allows you to explore shapes which are impossible in conventional construction ,,,so now a whole new world of shapes opens up as well and more effective ways of designing specific boards without having to make comprimises on shape because of being locked into design parameters , which are bound by current construction techniques ,,, how high can a 36 year old 100 kilo surfer boost , when your average grom is struggling for speed in the same waves ???

below is a quote from a 40 year old plus surfer , hes working with similar principles and dimensions , also breaking ground with variables of a unique nature based on common concepts ....
Quote:



I've boosted more
airs in a session than I've ever done before and I can't break it yet. I'm
basically freaking right now. I'm building another one today with different
flex.

__________________________________________________



ok i will leave it there ,,, this board is in the bag at the moment having the deck pressed on , so theres more to go now , but i will save it for tommorow ....

regards
BERT

truman finds his way into another world soon , after being locked in for all those years ....

ok guys i see some questions ,, i will answer any at the end ,, as most of them get answered as we go ,, i already see some clever deductions being made , and its yes to most of them ....

ok so youve seen the shaped deck , once thats done , lay your board deck down on a sheet of divinycell and trace around your board , then cut out the shape with a blade ....

so now you lay glass on your d cell , cut to shape and put some extra patches in the heavy traffic areas ...

now do your resin work directly onto the d cell ,, for the whole bottom which was a rectangle i used 150 grams of resin ,,,but just for the deck with less area and working directly onto the d cell i used 240 grams ... the foam sucks extra resin , but that helps support the deck better ...



continued ,,,,

now , get your wet sheet of d cell and place it on your deck , a few bits of masking tape to keep it in place so it doesnt move as your sliping it into the bag ..because the bottom contours are already pressed into the bottom of my board , at this stage its possible to press them out again if you dont support the shape youve made , so while its not visible , the contour mat is taped to the bottom of the board ... this time around you dont need the firm flexible sheeting underneath the board ,, that was only there to ensure the whole contour mat lefts it imprint in the bottom of the board ,, without a hard base behind the contour mat , you would get a softened version of your contour mat as half the mat would get pressed into your rocker support bed , which is only soft foam ....
this is your last chance to do any rocker tweaks or curve modifications ,,, in this case im pressing a 6-8 onto a 7-3 block so i want a little more cosmetic nose flip , just a simple wedge under the nose will do that ...
once this layer is formed down and resin sets , the curves will be set in concrete , no way you can change anything after that , at the moment the board still has enough flex to be pulled into a slightly different curve ...
as an example , if you get a few sheets of veneer or paper cardboard or even playing cards , bend them into a curve , then press tightly at the ends as if youd glued them together and try to bend them the other way ,, for something to flex it needs some shear movement , you can glue 2 flat sheets of something together and it will still move a bit and spring back to its original shape a bit , but glue 3 sheets together and it stays that way forever ....


now its back in the same bag , under vac ,,, you can clearly see the deck being pulled tight onto the board and the board being tightly pressed into the bed

heres another angle on that wedge under the nose tweaking the nose rocker ..


continued,,,

ready for some glass ,,i ended up spraying it on the bottom only on the flat , so the cross section of bottom skin d cell is still visible and the green rails and joins will all be visible ... i was going to put fabric over it,, but the industrial look started growing on me , so i thought id let it all be obvious in the finished thing ...


heres the deck , with finished shaped tail block (thanks halycon for the tail shape inspiration ).. you guys know the rest from here.....


ok thats it ....

here comes some numbers and facts ...

firstly the weight and statistics ...
the board is 6-8 x 22 x ? ,,i havent even measured it , i knew what i wanted and when it looked right that was ok for me ...
the board currently weighs before glassing 1263 grams ....
if it was a standard urethane blank using the lightest urethane possible , these same dimensions would be 1900 grams plus ... and thats being generous ...
if you glassed a urethane blank of that weight with 4oz bottom and 2x 4oz deck , youd pretty much have a disposable board youd be pushing 3 months out of ....
where as the board i have here cant even be pressure dented with my thumbs in the stage its in now before glassing , when i do press it it just springs back ,,, so what that means is , it will get glassed with 1 layer of 2oz on the bottom and 1 layer of 4 on the deck , so the finished weight in the water and surfing will be about the same as a superlight disposable urethane blank with 1 layer of 4 oz on the bottom unfinished before the deck is even glassed ...
and on top of that , if it didnt handle a couple of years of constant abuse id be surprised ...
here youll have a board lighter than what any current pro would be riding , lighter than any surftech or salomon ,,, and it wont snap in a hurry because the core is soft enough to let the top and bottom move past each other in a shearing motion ,, where as the surftechs allow there cores to be penetrated with resin making them brittle and snappable , plus making the outer skin work harder which means small dents will still appear under the feet ...
and the salomons are running a cored skin that is to thick making it stiff , and on top of that the skin material is to light so it cant support an outer glass job without folding under the front foot on any decent floater landing or solid bottom turn ....

now the price ...
theres less shaping work to be done than a conventional handshaped p/u ,,,
the blank was 150 in materials ,, theres less work in the bagging stage than glassing a conventional board ,, so if you were paying someone to bag , it would probably be the same rate as what a laminator would make ,,,
so you may add 100 aud to the price , but the reality is a urethane shortboard in oz can be anywhere from 400 to 700 dollars ...a poorly moulded surftech fetches 795 , not custom , not made for performance ... a salomon is 1400 ....
a board of this nature in oz , anyone would pay 1000 ,, see some margins there????
plus now youve all got the upper hand over all the profile brands on the market , mainly salomon and surftech....
so after 15 years of r&d this is my legacy to the surf industry ....
and the best part is if you guys have been blown away by this , you would freak big time if you knew what i build for a living , my techniques and strength to weight ratios on my current production boards ....

just talking randy french for a minute ...
i dont know the history of surftech , whether or not he ever tried to get it off the ground in the west through the existing industry ,, so there could be other reasons it ended up being made in thailand ,, maybe randy can fill us in ...
but the reality is randy has exposed alot of people to the concept of sandwich construction ...
so im grateful to randy for that because , its given me some exposure and credability for the work ive been doing all these years ...all of a sudden im not branded as an eccentric anymore and given the label obtuse ...
at last more people are experiencing first hand the performance differences in different materials ,,, for me now the last few years have been a real buzz , having long time critics at last come up and say " wow so you were right for all those years "....
if you look at the real reasons why this technology has been so slow in getting to the industry ,, youll see a handful of players supressing technology breakthroughs and putting up there own version of anti eps epoxy propaganda ...
so another bonus for me is the crew who actually made it hard for me to get access to the materials and purposely tried to belittle the advantages of this contruction through blatant propaganda , are now in a position to actually get nothing out of this construction style ....
appart from guys like greg loehr , you wont need to deal with any conventional surfboard material wholesalers , theyve basically cut them selves out the market by not embracing the new ideas as they were introduced ...im sorry to say , i forsee a time when a urethane blank will be considered redundant technology and grommets will say " check out the old skooler on that peice of junk"...

again , to me it shows that guys like greg were thinking ahead ,, in the sense of moving in the direction of wholesaling refined epoxy resins and offering alternatives .....

thats me ...
im off surfing , more refinement and r&d is calling me .....

regards
BERT

ps , you guys at salomon , if you want some real breakthrough stuff and you reckon your reputation is worth salvaging ,,, then you know what to do next time around ....whats that movie with the french karate guy ??? wrong bet ,or something like that ???

my purpose for doing this thread was to show the principals of vac forming ,whats possible and how you knock off 30 to 50 % off the weight and add 5 to 10 times the life expectancy to your board ...
i hear so many complaints about surfboards and how weak they are , well now its all here , the amount of information delivered in one hit , each picture and stage shows alot ...
once more crew work out whats possible , and the ammount of combinations that can be achieved , then finnally crew will appreciate what else can be achieved ...
because people will still be questioning how i get my current results ...
the board i showed you is still heavier and weaker with less performance than what i do now ..
but what i do is so far removed from current surfboard making techniques , that unless i showed some basics , everyone would continue to treat it as a novelty and put it in the to hard basket ....

at least now youve got somewhere to start ...


i reckon for what ive showed corecell is a better option ....
the secret to performance sandwich is shear movement , something that can bend along way and not fail is the key...
polywaffle versus crunchie ....

once more guys step into the playing field then well have more to talk about ....
right now , just go do the ideas that your thinking ....

hey bluejuice .. i was wondering if you would show how you do your d cell rail wraps ??
the biggest reason i ran in the parabolic rail direction in the first place was both a performance one , and having trouble wrapping a tight surfboard rail , with either timber , other foams or purpose built sandwich skins ...
surely you must have sections of sailboard rail that get as tight as a surfboard ???
another question , that core in one of your pics looked blue , or was it just the light or that blue filler they use for boats ???

im sure i was going to say something else ??itll come back to me later ...

regards
BERT