How far off are we supposed to sand the dried spackle smear on 1.5 lb eps? Do we take it all the way off to the foam beads leaving only the pores and cracks filled or do we leave a thin, thin film of spackle over the entire foam surface? Thanks
Are you going to paint it? If so, leave a uniform surface. If just clear, it just fills the cracks and pits. IMHO.
And in your IMHO. ??? Start by thinning the spackle with.an acrylic sealer ( like Behr floor and tile sealer) or distilled water. The minerals in tap water will turn the blank brown. Thin to the consistently of sour cream and spread with a plastic squeegee. Take of the excess with the squeegee. Let dry throughly(overnite) if necessary). Screen with a piece of worn out 220 screen.blow it of and it is ready for a clear or pain tented glass job. A film of spackle over the entire blank, especially the stringer isn’t necessary. I’ve done them this way for 2 or 3 years and you have to look extremely close to tell whether or not they are EPS or Poly. IMHO . Lowel
Do what McDing says. Everysurfer is right too but he did not explain it. We want our Epoxy resin to bond to the foam. A thin layer of spackle over the whole thing will prevent this. Use the spackle to fill the small voids. That way the resin will not drain into the blank but will still have contact with the foam. If you paint the board do several light coats and let the paint dry between coats.
Not to start a typical Swaylocks pissing war…
I’ve tried adding acrylic floor finish to thin lightweight spackle. Seemed to me as if the acrylic adds enough ‘stickum’ to where it pulls beads if I tried to peel it off. With that in mind, I totally covered the beads with a thin film of spackle, sanded but not to the foam except by accident in spots, spray painted (tempera thinned with acrylic floor finish), and glassed as normally would with epoxy. All is well several years later on the 12’6" aside from some minor pressure denting on deck. Oh yeah - glossed over a coarse sand with poly resin. No problems there either. The acrylic in the floor finish really seems to help with holding everything together in my opinion.
You’d have to look pretty damn close to tell if it’s EPS or urethane. And yes… the board is levitating on it’s own.
Since i stop using spackle, about 40 boards, my boards are thouger stay in better condition. I use a home made flexible epoxy foam instead spackle. Near all my boards have poly finish on epoxy cheater coat never have réal problems. Poly tear off slightly only if board is ding through the lam or buckle (and need repair). Only need à good prép. Try to use only iso poly.
Lemat,
Are you able to share any details on your flexible epoxy foam formula or how you use it? I ask because I wasted a lot of time looking into foaming epoxy years ago.
I make it from a local brand epoxy, they gave me some additives. One for flexibility wich is a modified epoxy wich inclued urethane that i mix and use with their standard industrial epoxy, then i have an other additive wich make the resin slightly foaming. I had specific syntactic foam hd bubbles and viscosity modifier in the mix. End product look like “chantilly cream” spread it hard on board then sand after cure. Surface look like a spackle one but hard to mark. I used to lam a layer of open waves wool glass fiber on deck with this mix as a first coat. This volumized 3D reinforced skin give a stiff tough light layer that resist well to dent.
Interesting. Thank you.
Mark,
I am constantly impressed, by the range of interesting materials, that you bring to the surfboard building process. Kudos to you!
It’s all too simple I guess. There just has to be a more complicated method. The “Sways” way— If it works, fix it.
Hmmm.
Early fall in 2014. Mr and Mrs Stingray had dinner with John M and Mrs John M. Chris P and Mrs Chris P,some are maried some are not…Good times for all !
Most pros in 2015 do not spakle because the foam is better now…and the word on Sways is that Fast and Final is now gray…that’s all…
Mrs Stingray wants to get out of the house…hopefully can have dinner with Swaylocks bros this spring,
Additive used by sicomin to make foaming epoxy resin is like what i use, you can adjust free air density. Those resin are often use to make light molding parts. With additives you can adjust mechanicals properties, mine is near a pu RIM resin idéal for my lenghwise reinforced foam. This material is use by starboard with a specific mat glass to make their tough skin, and by nsp too.
Stingray, you are right eps is better and epoxy is faster no realy need to seal foam anymore. I still do it because i do tint and i find finish better and far easiest for cut lap. Spackle is à good way to go for plain i think, but i see some spackle disaster even with well known brand. But here, in Europe, quality of big brand surfboards are not always as good original.
Sherwin Williams brand lightweight spackle is the same as the old DAP fastnfinal…and it’s pure white too. I have been using it for about a year now, it works fine.
…there s some facts:
-What Mcding says about complicating simple stuff, is right.
-PS boards are everywhere not only in USA and that spackle brand is not global; nobody knows a super white but nobody cares and most PS boards are sandwiched so who cares.
-I always see threads with the last plastic fiber and trying exotic techniques…then in the photos the work is just amateurish; I can imagine in direct the quality…
“I’ve tried adding acrylic floor finish to thin lightweight spackle. Seemed to me as if the acrylic adds enough ‘stickum’ to where it pulls beads if I tried to peel it off. With that in mind, I totally covered the beads with a thin film of spackle, sanded but not to the foam except by accident in spots, spray painted (tempera thinned with acrylic floor finish), and glassed as normally would with epoxy. All is well several years later on the 12’6” aside from some minor pressure denting on deck."
Thank you John
That sounds great Stingray!