hemp , again.......

General Discussion
1

Today , I saw a hemp surfboard in the window of a clothing shop , so I decided to go in and check out the board.

I discovered this place also sells hemp material , in roll widths [5’ / 150cms wide !!]

And , after about a half hour of my questions [she was a very helpful , and patient , lady !] , I left with a price list , and a sample sheet …Stoked !!

…anyway , here’s the info I picked up today …

 cheers ! 



   ben


2

…here’s a link to some previous hemp threads , IF anyone is interested ???

cheers !

ben

http://www.swaylocks.com/forum/gforum.cgi?do=search_results&search_forum=all&search_string=hemp&search_type=AND&search_fields=sb&search_time=&search_user_username=&mh=25

3

Pretty expensive stuff, the best price is $9.95 a metre. Can you get some samples?

Now there’s an idea, use the stretch t shirt fabric, measure and cut, whip out the old sewing machine and make a board sock, iron on your logo, trim off the hems, slip it on and glass, no laps required…a bit like shrink wrapping…

4

Hi chipfish! looking forward to your hemp products.

I’d go for MR02 or MR11 for regular boards and MR09 for composite surfboards.

yeah it’s great the width is so wide.

Jimmy yoshio shibata.

5

hi Jimmy !

thanks for replying mate , I was hoping you would !

with the MR09 silk ones …

would the silk heat up a bit much with the fibreglass on top , and the resin hitting it , do you reckon ?

I was thinking of the MR11 for sure …it has nice wood chip patterns in it ! And 4oz or 6oz is what I would probably prefer [ ?nothing TOO thick ?]

Although , like Hicksy , for a FIN panel , I’d be quite happy to give the heavier , thicker MR01 8oz open weave a go , too , just to see if extra resin is needed or not ? [ and to compare how strong it is , also. ]

I also figure I can cut down on the amount of fibreglass cloth needed in a fin panel , to get the same thickness , because of the thickness of the hemp .

I’m thinking I would start with a couple of sets of thruster side fins first …one in 6oz and one in 8oz hemp inlays, for a comparison .

…Now , the question …

polyester , or epoxy resined ??

Which did you find worked “better” with hemp , Jimmy ?

and why ?

[ie: WHAT was easier ?? … for example , less waste / more working time with epoxy ? quicker gel times with polyester , good or bad ? less heat generated with using epoxy ?]

thanks for any help , mate , I really APPRECIATE it !!

I hope to read through some [ if not all ?] of these hemp threads at some stage , too …

…maybe “uses of hemp in the surfboard making and fin making fields”, would be a good subject to have in the “photo resources” , and / or the “story” / theme resources section here at swaylocks, too ?

cheers

ben

6

Kept passign this one by and then finally read it. Interesting Chip. Is there another name for hemp?

7
Quote:

Hi Ben

I reckon epoxy is better, bcause ofbetter bonding properties and when you use it warm it flows and wets out the cloth better, but be carefull with heat buildup when you use it in thick layers. Max layer thickess is 2 mm, then wait till it’s only sticky (2-3 hours) and apply the next layer. Poly will be quicker.

I’m interested in your findings, it should be a good one for doing sandwiches with vacuum.

Greetz from Sjoerd, you say the “oe” in dutch like the “oo” in cool

“If you use all hemp, sanding will be a nightmare and that’s if sanding is possible at all.”

http://www.swaylocks.com/forum/gforum.cgi?post=140431;search_string=hemp;guest=5527791#140431

Think about this for finpanels

8

Ben,

definitely use epoxy, natural fiber cloth takes longer to saturate and low viscosity epoxy will help with this.

The cloth soaks a lot of resin (approximately 1.5 times its own weight), so you will get heavy laminates.

If possible, cover it with a thin glass layer. Natural fibers will fray when sanded into.

The bleached cloth will give almost clear laminates, I recently made a skateboard deck with bleached flax and its hard to see the weaves (I can post pictures if interested)

9

" I recently made a skateboard deck with bleached flax and its hard to see the weaves (I can post pictures if interested) "

yes please , I would be VERY interested to see that !

And also , if anyone else would like to post shots of hemp surfboards , skateboards , fins …

then feel free to do so , here !

cheers

ben

10
Quote:

Kept passing this one by and then finally read it. Interesting Chip. Is there another name for hemp?

hi mate !

here’s a bit of info , c/- good ol’ google

http://www.hempnation.com/

…I don’t know , do you get hemp fabric in america ???

cheers

ben

11
Quote:

" definitely use epoxy, natural fiber cloth takes longer to saturate and low viscosity epoxy will help with this.

The cloth soaks a lot of resin (approximately 1.5 times its own weight), so you will get heavy laminates.

If possible, cover it with a thin glass layer. …"

yeah ,

actually I’d figure with the stuff being so thick [as thick as , or even thicker than some carbon fibre ?!] maybe only three layers of hemp to 25 layers of fibreglass cloth , for an fcs thickness fin panel .

And around maybe 30 layers of fibreglass cloth , and 4-6 layers [?] of hemp for a fin box thickness panel .

I’m looking at the ‘MR11’ hemp cloth [6oz , with wood chips] , for a board . I’d try it as a fin panel first though !

I wish Jim Banks was here , he’s been using hemp [in boards] for YEARS now .

His boards have a really nice “golden” colour to them , so I’m thinking

a] he uses west systems epoxy glassing them

b] he tints them a little

c] it goes darker / more ?yellow? when resin and fibreglass cloth is combined with it .

For a board , because of the strength of hemp , I would think of using 4oz cloth over the top , instead of my usual 5 oz or 6oz glass jobs .

Fin panels , and experimenting on scrap foam first , though !

[actually … thinking about it , I can combine both , and my previous "fabric inlay foam core fins " thread , by making a foam core hemp inlay 4 or 6oz glassed set of side fins ]

cheers !

ben

12

Okay …here is what the ‘MR11’ hemp [55% hemp and 45% Viscose , with wood chips] looks like up close . This is the 6oz material, and is available in rolls 150cms [5’] wide ! …

…burlap and hessian look “similar” , I guess [?] , but are MUCH thicker and coarser , from what I have seen.

cheers !

 ben

ben

13

Hi Ben,

here are two pics:

The first shows:

  1. bleached flax cloth (appr. 6 oz.), covered with 4 oz glass, with epoxy resin over birch ply

  2. my greasy fingerprints

  3. epoxy gloss coat problems (found some help in the archives, thanks!)

close up of the weave (looks like a lot of micro-cracks in the glass, but it´s the weave):

hope this helps

14

very interesting !

thanks heaps for that , it looks like a nice board !

I see what you mean about the bleached material not showing up that much …

thanks for that , it helped me decide on the darker coloured [?unbleached?] stuff .

cheers

ben

15
Quote:

…I don’t know , do you get hemp fabric in america ???

Yeah, it’s pretty easy to get a hold of the fabric online in the states. Also, a hemp place just opened up in downtown santa cruz…haven’t been in yet but it looks like it’s worth a look. The only problem with hemp is that it’s so politicized that you’re automaticly labeled a stoner if you use it. I’d be interested Chip to see if you have success building fins/foam boards/ etc using hemp without fiberglass on top?

Pat

16

" I’d be interested Chip to see if you have success building fins/foam boards/ etc using hemp without fiberglass on top? "

hi Pat !

Well, I WILL be using fibreglass on top of the hemp … about 25 layers of cloth , and 2 [maybe 3] layers of 6oz hemp material , for the fin panels.

With a surfboard , I would intend to use one layer of hemp, and at least one layer of 4oz fibreglass cloth over it , on the deck AND the bottom of the board . (Possibly one layer of 6oz instead of 4oz , depending how strong it seems on the scrap pieces of foam , which I would glass using 4oz first)

My scraps of foam will be used

  1. to see if it IS at all possible to lap the rails with hemp . From what I have read so far in the old hemp threads here , it sounds like it might be tricky ?

  2. also , possibly, for thin foam core fins … with 1 layer of 6oz hemp material inlay [? possibly even one layer each side of the fin ?] , covered by double 6oz fibreglass cloth each side of the fin, all glassed using epoxy , I think , at this stage . I “may” also do a set of side fins using polyester too , though , so I have a comparison set .

So , the short answer is …

yes , I am DEFINATELY using fibreglass cloth over the hemp material .

cheers !

 ben
17

by the way …

What colour are people’s hemp boards / fins / material here at sways ?

… I ask , because so far I have seen brown , yellow ochre , and almost olive coloured hemp boards here in west oz .

Does the stuff fade / change colour over time , I wonder ?

Or is it different dyed hemps , different coloured [?epoxy?] resins , or perhaps a light tint in the lam ?

…all options I’d consider …maybe in a foam core with hemp inlay fin or a fin panel , first , though.

cheers

ben
18

Hi,

Just a side note in that I would steer completely away from cotton blends. Something just tells me. I believe it would a) not be strong because it just isn’t and b) soak up even more goo then hemp

Given the added strength (perceived/real?) of an epoxy layup why would one use glass fabric over it? I too have been looking into hemp as an option but cost so far has dissuaded me. Same for epoxy really. I also read that a significant advantage would be to use european hemp due to longer warp strands.

I’d be very interested to see some pics of a board glassed with hemp, preferable without glass cloth and a board that’s been ridden.

\r

19

Hi, chip. I dont think that heat would be any problem when using the silk ones.

I have only worked with epoxy when using hemp so can’t really tell the difference when using poly.

And I’ve found that hemp laminates are VERY hard sand, produces lots of heat and the resin is easily melted while sanding so I’d go as slow as possible with 36 or 40 grit when foiling them.

looking forward to see them hempfins.

Jimmy yoshio shibata.

20

hi “2cold” !

“Given the added strength (perceived/real?) of an epoxy layup why would one use glass fabric over it?”

well, from what people here have written …sanding issues , and brittleness without the fibreglass protection .

Also , having to lap the rails .

I guess I will find out for myself , soon enough . [Thank goodness for foam scraps , eh ?!]

Jimmy [yoshio] ,

do you have any photos of your hemp boards you could post here please , mate ?

cheers !

ben

Where is Greg Loehr ? …Greg , do you have any photos of your hemp glassed boards , too , please ? cheers !