Hotseat: GraphiteMaster's Chris Russell

General Discussion
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Chris, would you mind commenting on sealing EPS?  It is a long suffering topic here on Swaylocks and the cause of families breaking up, divorces, alcohol binges, burning surfboards left annonymously in peoples front yards.  Your thoughts could save a marriage, a job, a life.  No pressure.  (Justin made me ask)

all the best

 

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EPS sealing is a great subject. I can offer my experience, what I’ve found personally and what I prefer. I’m never one to argue, so whatever someone finds they like and works best for them is what they should use. 
My brief background with EPS and Epoxy runs back to 2003ish when I worked at North Wind Glassing in San Diego. It was owned by Dan Mann (Mannkine) and had Brian Wynn (Wynn Surfboards) and Stu Kenson (SK Surfboards) working out of the building (Enter Name dropping comments here). Stu was an early adopter of EPS and had already been experimenting with EPS/ Epoxy builds stretching back to the late 80’s. At that time there was no such thing as an EPS blank that you could buy with rocker in it let alone a blank outline. Stu would buy EPS blocks 24” x 48” x 120” in both 1.5lb and 2lb density. The bead fusion and overall block quality was piss poor compared to todays EPS available. Or maybe it was just the manufacture we were getting it from.. He had several of his favorite rocker templates that he would hold in place on each side with nails as pins and then, with his sketchy hotwire wand and fan blasting, slowly cut the decks and bottoms out of each blank from the block. Generally there was some country music playing, the occasional unlit cigar in his mouth and always a Bass Master Camo color (thats colour in Aussies and Kiwi) trucker hat planted on his head.  
Dan was all over it and started ordering foam with Stu to make his own boards. The Epoxy at the time we first used sucked for surfboards until one of us (can’t remember who), ironically, came across Justin and Hank with Graphite Master. They had just begun to distribute and sell Resin Research Epoxy. RR had already been around for a bit and Greg Loehr had be fighting an up hill battle on educating and providing facts to combat the false hysteria surrounding Epoxy and it’s use with surfboards. If I remember correctly much of that educating happened on this very forum. When Stus experience on the Epoxy subject topped out we would email Greg and always got quick answers on what to do, how to do it and when.. One of those topics was getting the weights down, which included sealing the EPS blank with Spackling compound or making an Epoxy / Q-Cell mix. We tried everything and learned very quickly what worked best and what didn’t.  All this culminated in Stu and Dan having a solid knowledge base with the EPS / Epoxy builds right when Clark Foam decided to exit, leaving the industry scratching it’s collective heads. Several years later, when I had my own factory, Greg Mungall came in and worked out of my place for a brief period. Greg broke the mold several times over when he was created. One of those molds was his ability to think outside the box when it comes to a host of problems faced with building Epoxy boards. From him, I learned better methods and the logic behind them. Greg is one of the few Epoxy/EPS builders who can, on a regular basis, nail finish weights at or very close to a multiple layered vacuum bagged board. 
So why seal EPS?
EPS by it’s nature has gaps in it’s foam structure. Even the tightest bead fusions of EPS has very small gaps.
When the foam is shaped into a surfboard some of those gaps are exposed on the surface or pits are created from the foam tearing or ripping a bit. Yes, you can be super detailed and screen, sand and sand again with 220, 320 or even 400 to leave a very smooth almost non-pitted surface. But the EPS surface of the board is made up of the tops of full un-cut (non sanded beads) along with beads that have been, through the shaping process, cut in half, quartered and so on. These spots are technically softer than the full unaltered bead that have their original “skin” or bead wall surrounding them. 
The un sealed EPS blank has two results.
  1. The traditional lamination has Epoxy spread over the Fiberglass cloth and then work in with a squeegee. The small gaps between the beads along with the soft open / cut beads on the surface allows for the Epoxy to penetrate down into the surface of the foam. How deep the Epoxy penetrates depends on the density of the EPS used, quality of bead fusion, Viscosity of the Epoxy and surface condition from shaping. All these affect the amount of added resin weight left in the surface of the foam blank.
  2. The unsealed softer EPS surface deflects slightly at each pass of the squeegee. Although it doesn’t feel so bad, that minor deflections give enough allowing Resin to sneak under the edge of the squeegee and not get pulled out as intended. This results in Excess Resin left in the lamination itself and ultimately added resin weight. For an extreme example, try wetting a piece of 4oz on a piece of glass vs wetting the same 4oz on a piece of smooth 1lb foam. You have a much easier time pulling the excess resin over the hard surface. 
So to combat the above problems blank pre sealing came to be. I was told (or read somewhere) that Sail Board builders in the 80’s sealed their EPS blanks. I’m not sure if that was the origin of the idea but sounds logical. Sail Board builders where doing things in the 80’s that served as the seeds for most of the advanced building techniques used in the Surf and SUP industry and talked about on this forum.. i.e.. high density skins bagged over EPS cores, Carbon Vacuum bagged boards, closed Molded boards etc.. 
Epoxy / Q-Cell, Epoxy / Cab-o-sil , Light Wall Spackling Compound, and even Elmer's White Glue are all methods I’ve either tried or heard of. 
-Epoxy / Q-Cell / Chopped Fiber or other Resin thickeners are a great way to seal a blank. The thicker paste made by mixing in fillers increases the Resin Viscosity so it can not penetrate too deep into the foam and in turn adds much less weight than straight unfilled Epoxy. Once dry and after a light handed sand job, the resulting surface is nice and hard. The laminator now has a solid surface to push against and pull the maximum amount of Resin from the lamination. This method is time consuming though due to Mixing of the resin, doing one side at a time and of course the cure time before you can sand. All in all very involved. 
-Light Wall Spackling Compound has become the most common method to Seal EPS foam. It’s cheap when compared to Epoxy, light weight and fills just the surface gaps exposed. Usually mixed with water as a thinning agent for easier spreading and filling, Drying time, depending on temp and humidity, is 1-2 hours.The sand prep after dried is also much easier than the Epoxy /  Filler seal job. The resulting surface isn’t as firm as the Epoxy / Filler seal, but it’s solid enough. Resin will still penetrate into the top surface of exposed EPS beads, but not as deep if not sealed. It’s also firm enough to support the squeegee pressure and allow for a much better resin extraction from the lamination. This method is much less involved and as a result, especially in production where time is money, mostly used. The negative is the Spackling Compound is made for filling small holes in walls. The manufacturers never intended it’s use for surfboards. The color, once fairly white, has become darker over recent years (adding white adds cost) and as a result can leave a visible finish up against the Pure white EPS foam beads. It’s also a fairly weak structure when dry. When a delam test is applied, the lamination can rip away from the surface of the foam core much easier when compared to an Epoxy Seal. The spackling fill, when exposed to water again after dried, turns to a mushy mess. So dings are a bummer when sea water gets in and breaks the Spackling down. Airbrushers will also point out their general frustration with the difficulty of achieving a sharp tape line when compared to airbrushing a Polyurethane blanks. 
-Elmer’s Glue is something I have never tried. This is the one I had heard Sail Board builders and a few Surfboard builders used when I was still pulling power slides on my big wheel. 
The last, newest and my preferred method for sealing does brush into product promotion. So be warned, I have a bias here and a business gain. But non the less, this is somethings we worked hard on along with a few key customers important input and I wouldn’t mention it if it did’t work. 
To me, the perfect sealer is something that mixes the benefits of the Epoxy Seal and the Spackling Seal. Something that drys to a nice hard finish similar to Epoxy and permanently stays solid (does not break down with the reintroduction of water), has structure, is bright white, dries fast like normal spackling and sands back fairly easily. 
With that we developed what we have called Z Seal. Without giving away the actual formulation, it’s essentially a Spackling compound we have heavily tweaked with an increased level of Glass Bubbles, some chopped fiber, extra Titanium White and a mix of key adhesives all compatabile with Epoxy and EPS. The result is something that checks the above boxes. We have tested this internally for over a year along with a few key outside builders and brands that are experienced in EPS/ Epoxy builds with exceptional results. A bond to the EPS very close to an Epoxy seal, bright white matching the EPS beads, UV stable, still thins with water, screens/sands back well, allows for sharp airbrush lines and a very firm finish allowing for a strong shell to laminate against and in turn pull excess resin out. Overall something we are very happy about. 

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where can we obtain this new product?  in what quantities will it be available?  

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I’ve used it.  It worked well.  I thinned it a bit with distilled water.  I don’t know how to do links, but I started a thread a couple of months about this product.  Lowel

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Chris - thank you again for your time and insights - you have been very generous!

Care to discuss any thoughts about resin infusion (vs.  hand lam thrown in a vacuum bag)?

I was toying with the idea of a resin infusion build using the low absorbtion Soric LRC material as a ‘leave in place’ distribution media (mimicing the Lib Tech boards) …

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We currently have it availabel in 1 Gal pales and will have 1 quart pales (2-3 boardsworth) within two weeks. We did manufactuer 5 Gal pales but those sold to a few large customers quickly. We will make those again next production run we do in August. 

Sometime in June we will have an East Coast supplier set up to ship from. Still workign out the details on that. 

Hopefully Foam EZ will be carrying it soon as well.

In the mean time call our offices or message or email me direct if interested.

chris@graphitemaster.com

Office: 323-261-1107

 

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Resin Infusion of a custom board could be looked at as the Holy Grail for modern surfboard manufacturing. One shot lam, top and bottom with perfect Resin / Cloth ratio. Super flat and tight build.  Ah, if it were only that easy…

Do you plan on making a Mold? If so, it is very doable. Talk to, if you aren’t already, someone who infuses anything. Infusion works well when you have a part in a mold. Something firm the laminate can compress against forming it into the final shape. For a surfboard without a mold, you would be attempting to infuse a 360 degree part made up of a relatively soft core all at once. To my knowledge no one has successfully pulled this off (Infusing a non molded foam part all sides at once) with repeatable results. If anyone has they are holding onto their secret like I would if I won the Super Lotto… 

I don’t want to sound discouraging. I actually believe it can be done and that it’s only a matter of time until someone figures it out. Borrowing from one of my earlier responses, the F^ck up factor will be high trying to nail this one down.

The Soric material is a great leave in place flow media. You’d want to use the Soric SF 2mm as it will drape best (will not wrap a complete rail) and has the higher resin flow rate. You could cap that with a Double Bias cloth. Even though we really don’t sell it as such, the Double Bias materials we carry have been designed with Infusion in mind. They are used heavily in Wind Blade manufacturing where Infusion has become very popular. 

If you do give it a try, please keep me updated. 

 

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Sorry to butt in but soric has been around a while and hasn’t quite caught on. Heavy and stiff, the fin panel hex core, occasionally used as a deck reinforcement in windsurf boards that take 20 ft airs, it is like adding a screed of microballon slurry between glass layers. In fact if I wanted a tough, tough deck, I might use a layer of vector net and screed out microballons acros it as others have done.

…if you just want to flow resin, without the weight and stiffness of soric, why not use a mesh or net? think about it.

Also from what I gather the hex appearance of lib techs comes from the blank which is foam filled nida core or an equivalent, in other words the hexes are a plastic honeycomb going all the way from deck to bottom. Therefore not the lightest builds.

again please forgive my amateur intrusion and thanks Chris for sharing true pro advice.

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I don’t think theres a need for any apology for proving input that can posible save somoene some money in F-ups. Input from guys who have used the materials or have eperienced the material in use is what this forum is all about. Keep it coming…

Thanks!

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I recently see a libtech cut in half, not an industrictable board for a punchy beachbreak, so it’s really look like thin soric mat.

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BWD check out the Soric LRC, it is different from the fin panel Soric you are mentioning. Lower resin absorbtion and much larger cell sizes. Lemat has seen a lib tech broken and confirms that the hex is a thin layer - not the entire thickness of the core. It looks very much like the LRC but i could be wrong…

I doubt I will go through with it - sees more trouble than its worth…but … it could be fun :slight_smile:

Chris - I have been somewhat involved in a few infusion panels and have access to some people with extensive infusion experience (check this patent that they are listed as inventors on - they have shared some cool tricks with me)  http://www.google.com/patents/US20050073076

To your point about doing both sides at once without a mold, maybe you could combine a rocker table and bottom contour mat (a la Bert Burger) to mimic an adjustable one sided ‘mold’? It seems like you could do a foam core all at once…you mention soft foam being a roadblock…there must be a sweet spot with density so that it is firm enough to support the process while still being light enough to be worth the effort?

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any chance of getting some in australia?

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Grasshopper you can use soric lrc for surfboards, look at coresurf tech used by gunter Rohn grsurfboards.com . libtech foam is pinck really look like xps, skin is basalt inner soric and glass? make by infusion. I see guys that infuse poly resin on pu blank on one go, there is a vid on youtube, i will search… On one off keahana website they speack off it too.

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If you could throw out a ballpark price on your Z seal that would be nice… Southern California.

I have the same question as Keith Melville. Epoxy + pigment/tint + polyurthane blank = some crazy unexplained stuff…soft cure, golf ball bubbles, delams, worm like shrinking…and some boards just fine. I’ve talked to Keith many times. We are using top quality blanks…and Resin Research resin

My problem with people linking me to epoxy pigment sites is that the same people are not building boards with awesome color work…Thanks for all your input Chris. You did answer quite a few questions I had…

Stingray

 

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Sorry if I passed on bad info on libtech, I must have been mistaken. Still not sure about soric lrc, maker says it weighs only 115g/sm but soaks up 600 g/sm of resin. So it could take about 1kg resin for full wrap of many small to medium boards. Maybe better to use it differently, rails and patches etc. It is still on the list of things with which I would like to experiment.

 

 

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chris

do you have any knowledge regarding basalt fiber like what libtech uses versus any of the other choices?

holly/gilbertpumpernickle/mike talked about sourcing basalt from russia back in 2004 but it was a much darker fabric than what is seen in the libtech builds.

is it temp?

flex?

 

 

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I think Chris might be busy with the show this weekend (i.e. Making a living). Or maybe we need to renegotiate his contract for an extension. Let’s see if he gets back to us next week. 

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Chris, would you please comment on the use of innegra, either as a separate layer or maybe woven in some of your new  fabrics?  Proper role?

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Sorry everyone, got a little behind getting back to the questions.

Please email me for Z -Seal pricing as we are just finalizing what that will be. We will be selling direct to manufactuers and pointing single non resale builders to Foam EZ as they are much better set up to handle and service that customer. I don’t want to type a price here and have that undermine what our sub distributors will sell it for. Hopefully you can uderstand that. It will be more than standard Spackling Compound purely due to the increased manufactruing cost of all the fun additions we mixed in. Foam EZ will have Z seal available week after next and should have their pricing up soon. 

With the pigments, and like I stated before, I’m not the expert. Although wiht both quetions / experiences I am digging around to see what I can find. I have always felt, possibly incorrectly, that awsome color work really goes best with Polyester Resin. The colors always seem more briliant.  With that beeing said, when ever I ran into a production problem that made zero sense I would start looking at all the factors involved. Methods, environment and inputs. I would try and see what relationships the problems had from one board to the next. Normally this would point to one or two causes. It would be interesting for you guys to compare notes on the colors used on the projects that went south and soft. Start there and see if there is any connection. I will dig more into this and PM both of you with what I find.