John C.

TMann, If the thimble trick works please post the tip in a more generally read category. This thread and category is very specific to a small segment of readers I think? It'll be a long while before I'm cutting foam again to acid test the method. Thanks.

I've had wire break failure where the wire rubbs on the template, a tip from another forum was to slide 2 sewing machine thimbles onto the wire, the thimbles ride on the template, I'm anxious to try that method next foam cut session.

Canard Zone has been very helpful for my surfboard building project using Rutan type materials and methods, finally the board is all laminated, ready for finish. Regular surfboard finish is built up resin gloss coats sanded and polished to beauty. We want to use a paint type finish to insure as close to waterPROOF as possible, beauty is secondary. All the resins soak a certain small amount of moisture and I'd think the aviation designers would address this and the players on this forum would know something about what they're thinking about composite resins water absorption and coatings to minimise it. Any thoughts please? Thank you, John C. San Diego

Thank you aviation Folks , for the tips. A woodpecker device is being made up right now, test panel with fine nail holes being done today. Surface prep attention double checked for everything. Replicate Rutan methods more exactly, eg, correct micro slurry is really quite thin at 50/50 resin micro. The plane builders have this composite thing down. Moving on to the next steps now, gotta shape up a new full size panel and get it into the surf for durability testing :-) and if it survives, the panel really should get off to Mexico for some real life thermal tolerance tests :-) I'll let you know how things go. thanks again. John C

Thanks J. Matcho, Rick P, We are gettng out beyond my own limited experience so I went back to the Swaylocks board building forum to review and relearn what the real guys have experienced. I'll put you onto some interesting threads, but first. Should me move this conversation to a new thread here to allow the original EZ Ahab questions to come thru?? I'll leave that to you. The interesting threads: www.swaylocks.com>discussion>general discussion>general discussion search,type in XPS delamination. 22 results should show. Look at the thread titled, XPS foam gassing problem or XPS roll call. The players Bert Burger and Greg Loerh are real commercial builders/innovaters. Loerh puts out the Resin Research Epoxy, its good, Burger is very knowlegable, commercial and development as you'll see. A look at this thread and you'll know as much as I do except for our own particular delam problems under opaque carbon already mentioned. I've got 4 new test laminated coupons waiting for peel, bash and overheat tests starting today. John C.

Thanks RPelliccioitti for commenting on the surfboard delam issue. Yes, the point loads from hands knees and feet cause compressed foam and associated delam, its one of the worst board durability problems, we and many folks are working on the prob, but that's a durability prob. The laminating delam prob is occuring right in the shop for some people, soon therafter for others, it doesn't seem to be a use, durability thing. Our specific problem on 2 boards could be chaulked up to some other variables, first time using the blue foam, carbon fabric hard to wet out and see thru to see whats going on with the wet laminate...and other rank amateur variables, but the pro and pro/am industry is stymied by the Extruded Polystyrene. One commercial manufacturer in Oceanside Ca. near San Diego, talks about his particular problem, assessment and solution on his web site www.xtrsurfboards.com >FAQ. XTR and other smart enouph folks are always talking about the blowing agents coming out of the foam. Wouldn't the airplane wing just be blowing apart at altitude if that was the issue?? I'm going to persevere to duplicate the Rutan exact methods on next build using glass to see thru the laminate, we've also got the Rutan build booklet, Moldless Composite Homebuilt Sandwich Aircraft Construction, that book combined with the Video ought to do the education job?? Thru this thread I've confirmed that the plane builders are not gettng delam issues, that in itself is a big help toward figuring out what is going on with the surfboard laminations, thank you.

Here's some data on Dow blue foam. This data is from Fall '04 when I talked to a rep in the architectural foam department at Dow Styrofoam. See www.styrofoam.com > products, architech, the toll free numbers are the same as '04. I was asking about the Hi Load product line and Buoyancy billets. Hi Load 40 psi compressive strength 1.8 pcf. Hi Load 60 psi 2.2 pcf. Hi Load 100 psi 3.0 pcf. Buoyncy billet sheets 25 psi 1.6 pcf. Buoyancy billets blocks untrimmed about 1.8 pcf. End of that data. The 2 billets we own right now are coming in at about 2.0 pcf with an iffy kitchen scale and getting the volume dimenions 24"x10"x96" is tough because of the billet's wavy, round cornered, outer shape. I didn't weigh them when we first got them and they've been soaking up ambient humidity for 2 years. A/C Spruce lists 2 large cell blue foams, and one small celled blue foam, and now I'm getting confused.

Thanks Jon Matcho, I knew that if the plane builders were having delam it would be a huge topic and can't figure why the board builders have it as such a big problem when the plane builders don't. The board laminaters are real pros, do fantastic, thoughtful work, commercial and amateur. Epoxies are being used, many of the same ones lised in A/C Spruce catalog, eg. West, Jeffco. Boards need to be works of art so water clear resin is important, Resin Research Epoxy is commonly used. Rutan method surface preps, micro slurry, are being used with equal delam failures to, no pore filler, or alternative "sealing" methods such as lightweight wall Spackle smear. A tip from this site, I'll be vacuuming the foam pores before micro slurry next time. Temperature, Yes, a big factor, but this has been addressed big time and is probably only part of the issue. A white or clear board sits on beach, or roof of car, or in hot car but that can't match the temp of a white wing sitting on the asphault tarmac at Phoenix or any 100F inland location. I can't figure it, the board glassers are real experts, laminate all day long every day, the product needs to be perfect or its trash and those guys can't avoid the delams. I'm a once in while builder still intent on using the Rutan methods, we've got the video Building Rutan Composites, we still own 2 bouyancy billets and starting the next build, thats why the current push to get feedback. Past Dow XPS notes are in front of me now for the product data I've got, more later, Thanks. John C.

Amateur surfboard builder here, let me get in on this thread please. Just yesterday stumbled onto this site and thread while trying to figure out exactly which extruded polystyrene foam, XPS, the plane builders are using. The surfboard builders, us included, are having delam issues with all the XPS offerings and thru much homework have not found the plane builders to be having any delam probs, true?? We've been following Rutan methods since the 70's, only recently we kicked off the effort to use the plane builder materials and methods for the boards, we're using Dow bouyancy billets. All board builders are having delams and have mostly given up the effort on XPS in favor of expanded polystyrene, EPS, densities from 1 to 3 pcf, reference www.swaylocks.com. The notation on this thread about a past Canard Pusher note not to use bouyancy billets is very interesting and any feedback, references on if the plane builders are having blue wing foam delam issues please. I've got some pretty good notes on Dow XPS densities from talking with the reps at Dow but need to get that data better organised before posting. Thanks