Aloha, I have some red formula USBlanks to glass - what is the amount of fabric I need to keep from having shrinking problems. I will use UV Poly this time instead of RR epoxy. I had some mean shrinking problems with the combo of Red formula with RR. No matter if I used 6/6 deck or even carbon the stringer, fin boxes and lap edges would stay proud and the rest just crushed away??? Much thanks for help. Chris
I don't do epoxy over PU. I saw a thread here about shrinkage of epoxy over pu. You will be fine with 4+4 deck 4 bottom and pe resin. I dont think it is the glass, but rather the resin.
good luck
I had some mean shrinking problems with the combo of Red formula with RR. No matter if I used 6/6 deck or even carbon the stringer, fin boxes and lap edges would stay proud and the rest just crushed
I saw a thread here about shrinkage of epoxy over pu.
Can anyone elaborate? I’ve not heard of this shrinkage “of epoxy over pu.” I’ve always heard you could glass pu w/epoxy no problem.
Maybe i'm going nuts. I swear i saw something on that subject on here about a month ago. i think it was a certain kind of epoxy though.
Never have I had : Surf Blanks America, US Blanks shrink with Epoxy?
Do it for team boards.
Single 4 deck
Single 4 bottom
Maybe some foot patches.
4x4 deck, 4 bottom, perfect combo
i saw the same thing with RR over clark foam. supposedly the newer blue resins fix this problem. did you glass the red blanks with clear RR or one of the newer blue RR (CE, Kwik Kick)??
there were two threads earlier this year titled something like 'epoxy shrinking' and 'epoxy yellowing' that has a lot of other peoples' accounts on these problems.
surfding - how old are the pu boards glassed with epoxy? have any that are over a year old? have you glassed any pu with the clear RR or just with the blue RR (CE / Kwik Kick)??
Based on your description; The type of shrinking you are talking about will happen right away, not a year down the road. Earlier threads that discuissed this were not exclusive to Epoxy. Some of the early overseas foam was more prone to shrinking. I've never seen a Clark do what you are describing. I have seen normal collapse though along the stringer and footwelds on the deck from normal usage and a light weight glass job. I had one out of ten overseas blanks shrink. The board was new and unused and shrunk up like it had been vac-wrapped within one week. The only blank out of ten of the same foam to collapse. i still have two boards made of the same foam. They are fine. Don't know why it happened. Gave up trying to figure it out . Based on what others have told me; It just occasionally happens. The better American foam gets the less likly.
did a longboard with usblanks red and poly resin in may. ridden most every day since then. some mild heel dents on the deck. no shrinkage anywhere. 6 deck/6 bottom, weighs 16 lbs w/o fins. 9’0 x 23 x 2 5/8.
bull dust stop floging a dead horse’’ amateurs have been known to stuff up the best of materials
learn to select the right foam density for the job
Does anyone have pictures, and does anyone who knows have an explanation? I still find it hard to believe that “plain old” RR “made” the foam shrink. Huie is probably right… ;-)
huie,
I actually meant that "I don't do epoxy over PU" because I have never done epoxy over pu. not because I have somthing against it. It probably works fine, but I don't know anything about it though. I was telling the original poster of the thread that PE resin will work fine(no shrinking), and that their was a thread a while back about epoxy and PU shrinkage. Hope that no one else read that wrong :)
Grasshopper I have a few over a year old.
I used the slower set stuff.
I have a few gallons because I use it for vacuum bagging.
In production we use RR Kwick Kick for eps. We go through quite a bit.
Mostly Poly for PU however once in a while do a PU/Epoxy without any issues.
Drawing on my vast experience of 2 epoxy boards over poly U foam. No problem and I wouldn’t hesitate doing more. In fact, I’m going to start using more epoxy because I think the stuff. It is more durable and i can use a lighter cloth. My last Clark blank(how long ago was that?) is epoxy resin. I still ride it and it still has some pop in it. My last minisimms board is epoxy over USBlanks poly U. No problem. No denting, cracks, or anything else that I have noticed. /tgat epoxy does get hot, though. Get it spread out on your board and work it in. Don’t leave it in the pot too long! For what its worth. Mike
pictures in this thread: http://www2.swaylocks.com/forums/least-yellowing-epoxy?page=1
This is NOT bad foam. made about 75 boards the year the pics were taken - all Clark cores, red, blue and green. majority of them epoxy glass jobs. all epoxy glass jobs did this after 6 months to a year. none of the boards glassed with polyester did. a few of the polyester glassed boards from then are still being ridden!
A few have posted on here with similar results with US blanks (basically same formula as Clark). Loehr has stated that this is because there is no UV inhibitor in the clear resin. Supposedly the blue resins (CE, Kwick Kick) have this additive and should work fine. I haven’t tried it yet. I have used CE and KK on EPS with very good results.
Huie claims Clark/US blanks foam is no good. But it works great with polyester resin.
Others have stated that epoxy/PU of different brands work fine. Also a gloss coat of polyester over the RR and Clark/US has worked well.
It will be interesting to see if Chris glassed his with the clear resin or with the blue resin? (I suspect it was the clear resin with no UV inhibitor…)
Huie claims Clark/US blanks foam is no good. But it works great with polyester resin.
uhhh’’ can you not read’’ or is it you dont want to read?