Hotseat: GraphiteMaster's Chris Russell

 

(Chris is GraphiteMaster’s technical advisor  and head of sales for North America.  He is a fountain of knowledge regarding fiberglassing.  He works with Justin Ternes and Hank Johns, who many of you already know.)

Chris, Welcome to Swaylocks.  Thanks for siting in and letting us pick your brain.  I have a bunch of questions, but I’ll restrict them to just one for the moment.

Fiberglassing is like a black art for many of us.  Is there a way to come up to speed on weaves and yarns and warps and fills and finishes and interlaminar bonding, and whatever else we need to know?  A book?  A video?  A seminar?  Actually, four questions.

all the best

Chris,

Besides use of Epoxy resin, what to you think about the use of some of the other resin mixes out there? Polyester, Vinylester, and The mixture of Acrylic/Poly resin that RevChem sells in conjunction with some of the composites you guys sell?

Tell Hank and Justin I said hello.

 

 

Thanks Greg and everyone keeping Swaylocks going. 
Appreciate the forum and any help or added information Graphite Master can add to someones library of knowledge. 
My library is always growing so I am here to learn as much as spew anything useful. 
 
Fiberglass. How deep do you want to dive?
This can easily get long winded and boring quickly.
Prior to working with Graphite Master I knew all I really cared to know about Fiberglass.
Manufactuer (BGF, JPS, Hexcel), Weave (Plain, Twill, Satin), Weight (4 oz, 5 oz, 6 oz) and Glass type (E, S, D). That was it. Truth be told, that is really all one needs to know to build a decent quality board. Except now there are new added types of Multuaxial Fabrics that, in my opinion, are very exciting for modern surfboard construction. 
With all composites Fiberglass gets brutally boring and complicated the more you learn about it. 
If your bored, lonely or both you can learn how actual Fibers are made here. 
http://www.compositesworld.com/articles/the-making-of-glass-fiber
I’ll skip the deep details and boredom and get into what I think is more applicable and interesting when it comes to Surfboard construction. I’m assuming most of this everyone knows but I’ll do my best to touch on it for background. 
Something to keep in Mind. To date the standard Plain Weave Fiberglass for Surfboard Production has evolved around Polyester Resin.
I guess the best way is to start with the actual Yarns.
Basically Yarns are produced from Silica which is melted and protruded into fibers. During the process a sizing agent is added to the fibers. A Sizing agent is a Fiber Producers “Magic” formula which is basically a mixture of materials (Water, Coupling Agent, Lubricant, Film Former, Wetting Agent, Crosslink Agent and Antistatic Agent) applied to the surface of a reinforcement fiber. The mixture and exact ingredients are closely held secrets that make one Yarn better or worse than another. ( yes, I pulled the straight off a article in a massive book I was given when I joined Graphite Master)
 
E = Stands for Electrical and is the standard Yarn Used in Surfboard Fiberglass.
S = High Strength. Pretty self explainitory. Used for areas where increased reinforcement is needed. Has a significantly higher Tensile Strength and Tensile Modulus than E Glass. 
D = Direct Size is a E Glass Yarn that is treated differently. E Glass has an additional chemical wash and heated processes applied to achieve it's desired finish after weaving. Direct Size Yarns are treated in a way prior to weaving that they do not require the post weaving wash and bake.  Because of this, Direct Size Yarns have a higher Tensile strength and Tensile Modulus than E Glass Yarns but not as strong as S Glass Yarns.
 
Twisted or Flat
Most Yarns for the Fabrics used in Surfboard Fiberglass are twisted pairs of glass strands. The twisted strands help to bulk the fabric up, help in wet out and help in drape once woven. There are non twisted yarns called Flat Yarns where a single Flat Yarn equals two twisted Yarns. These are generally thinner and tighter looking. They tend to make stronger woven fabrics that feel stiffer when dry and are much harder to wet out. 
 
Finish
BGF, JPS, Hexcel all have their own post weaving surf fabric Finishes. The Finish is the chemical bath and/or water wash that the woven cloth goes through. Each are different and are the reason along with the Yarn Sizing that some of you love or hate certain Fiberglass companies. Some are stiffer, some drape better, cut better and some are clearer than others. I will here one very respectable laminator tell me how much he hates Fiberglass A and Loves Fiberglass B while another equally respectable laminator will tell me the opposite. Bottom line, they are all good once you get use to the characteristics of how they work. 
 
Weaves.
Pretty much all clear standard Fiberglass for surfboards is Plain Weave. Thats a over and under pattern reoccurring. 
Plain Weaves are the easiest to work with when using Polyester Resin, pull and cut straight (for the most part) and tend to wet out the best. 
Plain Weave Fiberglass has the 0º or Warp direction (think the direction it runs lengthwise through the roll) and the 90º or Fill (Weft) direction (side to side). The standard E glass 4 oz (also know as 1522) has 24 ends in the Warp and 22 in the Fill. Warp glass is a simple shift in the number of Warp and Fill ends in a woven fabric. 30 ends in the Warp and 16 in the Fill. Increasing the number in the lengthwise direction of the board where it’s needed and decreasing it in the side to side direction. Warp glass also uses a Flat yarn in the Fill direction which is why it tends to lay flatter and feel a touch stiffer pre wet out. 
 
Twill Weaves are worth mentioning since they are common with Carbon Fiber fabrics. Twill Weaves tend to drape very well and fit complex curves. Good for Racing SUPs cockpits etc..Twill Weaves, technically, are  slightly stronger than Plain weaves because of the less crimping (over and under). 
 
Custom Twills and Patterns
Advancements in weaving utilizing computers have made for some pretty interesting possibilities in weave patterns. Company logos woven into carbon, Twill V Patterns, Hexagon Patterns and so on are possible. I have only seen these applicable with All Carbon Fabrics and Carbon/ Innegra, Carbon/ Kevlar Hybrids. 
 
Unidirectional
All fibers in the fabric are running in the same direction. Generally held together with a polyester or glass yarn in the Fill. The Carbon woven tapes you see on the tails of Surfboards could be considered a Unidirectional carbon even though they are woven with E Glass in the Fill. The carbon is all running in the same warp direction.
 
Non Woven Multiaxials
Off Axis Double Bias Fiber Glass or Carbon Fabrics are generally two layers of fabric in off Axis directions (the Axis being 0º or think nose to tail direction)  ie.. +/-45º, +/- 30º  held together by an adhesive or fill stitch. There are Triple, Quad and so on Multiaxials as well. 
These are not necessarily new, but really just becoming more accessible to Surfboard builders due to the price coming down to reasonable levels. Aerospace, Marine, Snowboards and many other industries have been using these to their benefit for a long time now. Laminations with the Double Bias +/- 45º 5.5oz glass are stronger and lighter when compared to a plain weave glass at the same weight. Again no crimping at all (over and under) to pool resin and weaken the lamination. 
 
First response in and long winded already..Sorry 

Hi Berry,

 
Full disclosuer. The majority of my boards are laminated with Epoxy. My Poly built boards are either Full Resin color boards or old guns I've had for years. 
 
I think Polyester Resin has been the work horse of Surfboard production for over 60 years. It's relativly cheap, easy to work with, takes color well, is predictable (when used by an experienced person), sands easy and gerneraly makes a decent board. Pretty much the main reasons it's stuck around for so long as it has.  It constantly gets hit with rumors of it's demise but just keeps hammering along. I actually think social media has shined the light on Polyester resin in a way by giving the laminators who mix colors (who are artits) a forum to show off their work and gain a following. Were seeign colors used and mixed in ways that were rare 15 years ago. I guess not rare 15 years ago, just more customers now willing to drop the extra money deserved for a board looking like that.  Now there are dozens of guys doing this all over. The kick time, color and that predictability I mentioned above would not be as easy if these boards where made with Tinted Epoxies. Or at least the results would be different. 

Polyester is brittle though when compared to Vinylester and Epoxy Resins. In my opinion, not the best resin to use for a light weight performance shortboard. Polyester is also not the best wetting out resin when using Carbon, Aramids (Kevlar , Technora) or Innegra.

 
I first used Vinylester around 2003ish at North Wind Glassing, a glass shop I worked at in San Diego. I remember it had an odd smell compared to Polyester, was not clear (kinda yellow/ brown) and seemed thick. I din't know it could be thinned with Styrene at the time. Actually didn't know much at all about it at the time other than I was scared of it becasue it smelled different and that it was used by some boat builders. Since I've read up a bit but have not used it again. I know it has greater elongation than Polyester and is not as clear.
 
I think the clearity is really the main reason it never found it's way into the Surfboard world. That and no one invested any time, (other than the UV Vinylester that is fairly expensive) that I know of, into developing a surfboard specific Vinylester Resin. Not to mention the massive up hill battle trying to convince guys set in their ways to try something new.  All the technically jarbal points to it being a better / stronger resin than Polyester. The modern Epoxy push also most likely pushed Vinylesters out of most peoples radars. Greg Lohrs Resin Research Epoxy system was/is so easy to use and pushed by someone who knew how to build boards.   

Now there are at least half a dozen Surf specific Epoxies. Compettition for market share has truely pushed the quality, workability and perfoemance of the end product to new heights. 

 
I've only heard bits and pieces about the Arcylic / Poly Resin. I have not had a chance to see it or play with it yet so I can't comment on it's positives or negatives or how it works with Carbon, Aramids or Innegra fabrics.   

Many thanks Chris. A fountain of knowledge. 

All the best

Hey Chris—  alot micro wavers around here.  Tell’em to be careful with that RR and the micro.  Stunk up my place for a couple of days.  When I got right it sure made it flow tho.  Lowel

Nice overview.

Good information is never too long.


Hi Lowel,

 
The Microwave can be your friend on a cold day or completely ruin your project. 
An important thing to keep in mind is that every Microwave heats slighly different. So 5 seconds on one may equal 10 seconds on another. 
If your place stunk like you described I'd bet you nuked it for too long. Your container, although fine for mixing Epoxy, may not have been rated to exceed a certain temp and could have been the source of your smell. 
 
For starters if anyone is going to use the Microwave to heat / thin any Epoxy, the A side should be the only thing put in if anything at all. Putting Mixed or even unmixed A & B in the Microwave is a big no no. 
 
The problem with the Microwave is you can't actually tell what the temp of your A side is after 5, 7 or 10 seconds. Just that it is warm, hot or hotter. If you have a ton of experience with it then you've srewed up enough mixtures to know exactly how long you want it in and what the results will be. In most cases the Microwave will heat the A side way above it's ideal working temp of about 75 degrees F. A useful tool to have handy when working with Epoxy is a thermal laser thermometer.

http://www.homedepot.com/b/Electrical-Electrical-Tools-Accessories-Electrical-Test-Meters/Infrared-Thermometer/N-5yc1vZboffZ1z1180y

A safer solution to thinning the Part A is to fill a bucket with hot water and place your jug of the A side in it for 30 minutes to an hour prior to working with it. Time in the hot water depends on how cold it actually has been stored at. Thats the safest and recomended way to heat up Epoxy. 

 
In cold envireonments, it's important to keep in mind that when the heated A side is mixed with the unheated B side the temp of you mixture will come downand thicken slightly once mixed. For this reason it's good to heat the B seperately in to around 75 degrees F in the bucket of hot water mentioned above.
 
Something that most guys most likley don't think about on cold days (and possible the source to over heating the next time they make a mix) is when you have a nice thin perfectly mixed and heated system, it will instantly cool and begin to thicken when you pour and spread it onto the cold foam board. For this reason, if you have the space, it is good to preheat the actual shaped blank. This really only applies on cold days. Pre heating can be as simple as bringing your shaped blank into the house the night before, putting it in the car with the heat on while you get coffee or, if your set up for it, having a heat controlled room to work in. A heated blanket is another trick that you can use. 

Thanks for contributing! I am most interested in the “newer” or alternative fibers, from a background of surfing as well as kiteboarding and boating.

I recently bought a board laminated with epoxy and lower modulus fibers - apparently polyester and perhaps nylon. It has pretty much amazed me so far with its light weight and excellent ding resistance, while keeping a good feel, unlike some composite sandwich boards and other alternatives I have seen and tried. Weight is like a light PU/polyester resin board, but I have banged it on rocks and knocked into it with kite bars etc and it hasn’t dinged, just bounces back, and still has a great feel as a surfboard. Seems a like great direction.

I know vacuum or infusion is often key to getting good laminates with some of these materials since they can sometimes “float” in resin, but so far except here, people tend to treat the subject as “Top Secret.”

But after all it is still a question of cloth and glue, whether carbon glass or plastic/synthetic. Any advice or comment on techniques to use some of these non-glass fibers, or rundown of what GM offers and how it can be used would be great! Especially what could be helpful to small builders, amateurs or people looking to branch out. Whether you want to talk nylons, carbon hybrids, polyester, always curious…

Thanks!!

Yes I have screwed up one or two  small batches that were luckily only for ding repair.  Part A only.  5–10 seconds.  And never pop it in and walk away.  Lowel

Chris, the question comes up here often about whether a lighter weave belongs on the outside or the inside of the lamination stack.  Example, a 4 oz and a 6 oz deck.   Intuitively, it seems the lighter weave would go outside to reduce the need for fill coat and thus reduce weight?  Or is there something else at play to consider?

Great rundown GM - thank you for your time!

Interesting how this works: Laminations with the Double Bias +/- 45º 5.5oz glass are stronger and lighter when compared to a plain weave glass at the same weight. Again no crimping at all (over and under) to pool resin and weaken the lamination. 

BUT the flex pattern will be different…the bias weave will allow flex longitudinally and be stiff torsionally (resisting twist). where the 0/90 weave will be stiff lengthwise but flex torsionally (allow twist). do we want one vs. the other for high performance surfing? do we put one layer of bias and one layer of 0/90 to make a dimensionally stable laminate (and in doing so lock up flex in all directions)?

what are your thoughts on carbon strips to stiffen a stringerless board - best placed on top, on bottom, in middle of core, etc?

Greats stuff here so far.

Four points. Three questions and a general statement of stoke

Questions

  1. Define twill

  2. Have you heard of thinning out epoxy with alcohol. I read about it on a wooden board buildint forum, I purposely used it to laminate on a really lightweight EPS blank, it bled into the eps and created a great bond, a super strong board and a very interesting flex, I really like it.

  3. What do you know about full carbon laminates? How do they effect the flex characteristics of a surf board.

Stoke

  1. I have been given some new cloth by an awesome company in australia “sanded”, Its a Nylextra hybrid cloth… sounds very exciting. Cant wait to try it. Apparantly it has the impact resistance but maintains the flex characteristics.

 

 

I know you started this with mentioning Nylons but my experience is more with Kevlar, Technora and Innegra. 
The Hybrid Innegra Fabrics, Kevlar Hybrids or Technora Hybrids can offer properties simular to what you described in the board you bought that is hard to ding. They do best with Epoxy Resin for easier wet out and although you can hand lam them, your best results would be under vacuum pressure. If hand lamming it is pretty important to cap them with at least one layer of glass. The weight of that layer (2 oz, 3 oz, 4oz etc) depends on what you are trying to achieve in the final built board. The cap layer not only helps keep things tight it can act as a bit of a sacrificial layer when sanding. If you burn through parts of the hotcoat you have the glass to hit first and see before you burn into The Innegra or Aramid which are not sand friendly.
 
GM offers Vector Net materials in all Innegra or all Technora (Aramid simular to Kevlar) Styles. Although fairly gapped, the styles are fairly easy to hand lam and have shown to provide increased impact resistance as well as support the glass cap above which can reduce buckling. The Technora versions have shown to provide the most benefit for decreased buckling. Unfortunately most brands are using this material incorectly as tail reinforcment or fashion hits on the tail. They work best as a full lam under the glass. Some of the strongest ropes are made with these fibers and when laid in the Vector pattern they tighten under load and support the glass over them. Think of a chineese finger trap. As you pull it tightens. 
 
The Aramids and Innegra Fibers give toughness and dampening to the board or part being built. I think simply explained, the Fiber cores stay dry after lamination. They are encapsulated with Resin but not penetrated to the core. So impact stress is absorbed by these fibers and dispersed. The “dampening” word gets tossed in with these materials as well. And the reasons are the same. Energy is absorbed and dispersed by the fibers. 
 


Honestly this is preference and really relates to what your desired end result is. 

Heavier cloth over the top will result in a slightly tougher / harder rail and a touch of a heavier board. 

I’ve made boards both ways for step ups and really couldn’t tell the difference. They both broke over the course of a winter. 

But I do agree you can get a flatter hotcoat with a 4oz over a 6oz. Especially when using a Warp glass on top. The Flat Yarns used in teh Fill direction make for a nice hotcoat surface. 

The old flex debate. I look at this very simply. The thickness and foam density of the board are playing into how they flex or don’t flex more than given credit. Tortional flex is happening in the thinner parts of the boards that are receiving the most amount of pressuer from the rider and the wave. ie. The Tails. The foam core is doing more to hinder or help (depends how yo look at this) flex than most think. 

Check out Steve Pendos PendoFlex boards in San Diego. He hogs foam out of the tails and reglasses these areas to get the tails to flex / spring more. Bottom line is there really is no wrong way to build a board. An open minded surfer can make stiff board or a noodle work. It just takes a differnt approach to the wave. I think thats whats unique to this industry. Lots of dreamers, smart technical thinkers and a whole host of simple and advance materials to play with. Pretty much an open canvase. 

To answer a part of your question regarding wanting one orientation vs another for high performance surfing… I don’t know… I do know I can get a lighter board that is a little tougher using a Multiaxial Double Bias when compared to standard Plain weave fabric at the same weigth… Weight to me is the most important. A light responsive board for small waves feels amaizing. While a solid feeling gun is the right feel in big surf. 

Carbon strips on stringerless boards are adding stiffness where the wood stringer was doing the job before. Except instead of a wood I beam you are now placing the stifness in the skins. They don’t feel the same as a wood stringer, but this is not a bad thing to me. There is probably 50 ways to build a simular feeling board with the carbon placed differently on each one. Again thickness of the shape and foam density comes into play more than most think. A thicker board may only need carbon on the bottom while a thinner board would benefit from the tape on both sides. 

I think an important key is to not have any dramatic stops in the tape. Hence the arrow cuts and having the carbon tapes run past the front fins. 

1. https://en.wikipedia.org/wiki/Twill  Does a better job than me describing Twill. Although I have the nice picture below for a visual. 

  1. Yes. You can thin Epoxy with Denatured Alcohole. I belive Greg Lohr told me never to exceed 3%-5% max. But that is for the Resin Research system. I’d assume other Epoxy systems would not be much different. 

  2. Carbon is not the answer to all builds but it defientely has it’s place.  I have several boards at all times that are built this way from both Dan Mann and Stu Kenson. Carbon built boards require more load to flex and they return faster when compared to a all Fiberglass board. Again, for me, I’m paying more attention to the weight savings with single layers of 5.5 oz Carbon Plain weave or like on my newer ones, single layers of the Double Bias Carbon at 150 gsm (4.42 oz). Single layers of Carbon can break, and when they do they make a loud noise… This past winter we experimented with our Vector Net XPT 227 (Tenchnora) under the carbon lams to see if it reduced failure. The results have been pretty impressive. I think what is more important than the affect on flex is the ability to take designs to new areas where traditional fiberglass may not be strong enough to support or stiffen thin areas. Some of Dans designs are good examples of this. He’s made me some new side cuts with extremely thin rails in the tail area that would fall apart if normal fiberglass were used alone. 

  3. Sharing Stoke is always good. That material looks interesting. Basalt has been used with varying degrees of success in surfboards. But nothing to date that has taken off. A Hybrid with a Nylon sounds worth investigating. 

"A Hybrid with a Nylon sounds worth investigating. "

Does Graphite Masters have the ability to get custom fabric runs made? I looked into having a nylon/ twaron blend woven from a mill, but minimum order was hundreds of yards, and thousands of dollars.

Warp glass was a big fad for a while with some of the bigger board builders.  And little ones too I guess.  Greg Loehr counciled against it and favored so called X glass or multi axis glass or just balanced bi-axial.  Is there a proper role for warp glass in surfboards?

Hi Chris -

Good of you to take this on.  It is a deep subject.

A friend of mine did an interview with an industry legend for a magazine article years back.  One of the things the legend guy mentioned (I don’t remember if it actually made it to the article) was how toxic the chromium used in volan treatment really is and how hypocritical it was of all the new-age eco-hipsters to be using it. Obviously not after it’s glassed but in the rinsing process after treatment.

I see it repeatedly in the media how various guys tout it’s alleged benefit in a stronger glass job.  I personally am of the opinion that ounce for ounce, the fabric finish bears no impact on the strength of the reinforcement assuming the fabric is being used with compatable resin.  

I have also been seeing the wide ‘tape-like’ weave of some of the newer carbon fabrics.  The theory being that the flatter weave allows a more direct linear component to the tension aspect of the fibers.  (Less ‘up and down’ in the ‘over/under’) 

This makes sense to me and I’ve been much less dismissive of the marketing claims on this one.

Not really questions here - your comments please?