hi,
can anyone tell me how much resin i need to glass a 6'4" shortboard.
thanks
Good question, I hope someone knows< I would like to see if there is a formula for figuring out resin amount to board size, and does the same formula work for epoxy?
Depends on how much glass you use.
What my epoxy seller told me is to use the same weight (in epoxy) as you use in glass.
Easy calculation. if you use 2m2 in 160g/m2 glass then you need 340g epoxy. Same will apply for the imperial system offcourse. I always have to much when I don’t count the glass I cut off.
But you can estimate or weigh (most accurate) what you cut off.
If nessecary mixing a little bit more isn’t that hard (normally not nessecary).
With 1kg resin I can glass a shortboard.
(I assume that poly works the same way but somebody else should confirm that, maybe you need a little bit more)
the amount of resin you need depends on size of board,finish,glasssing skill. Most cases i can glass any board 7’0 and under with a gallon or less fun board style boards around 8’0 can take around 1 1/2 gallon with a polished finished long boards are about the same some times more and i am not a pro glasser so this should help you out. try to always use the same size bucket so you know how much to fill them .hope this helps.
for a standard 6’4’’ short board i use approx 18-20 oz for the bottom 4oz lamination and 32 for the top 4oz/4oz lam. as someone pointed out, your level of experience will dictate how much run-off you can catch and reuse. my advice is to pour out more than you think you will need, if you are using a uv curing resin, you can return the unused portion to the container for use another time.
brasco
I always use this formula for epoxy and it usually comes out good. 1 oz. for each 24" width, linear foot of lamination. I usually mix to an multiple of the ratio to keep each component even to the ounce. So if I'm using a 2:1 and lam'ing a 10'7" I'll mix up 12 oz. If I notice that my lam will have an excess of resin, I usually setup to do a fin panel or some other glue up at the same time.
This works for double 4 or 6 oz. lams. Haven't tried a double 6 or heavier cloth.
I use the same formula for fill coats as well.
I just glassed a 6'6 thruster with epoxy here is the schedule:
4 oz bottom = 10 oz resin and 5 oz hardener = 15 total oz.
4 + 4 oz deck = 12 oz resin and 6 oz hardener = 18 total oz
hotcoat bottom = 4 oz resin 2 oz hardener = 6 total oz
hotcoat deck = 4 oz resin 2 oz hardener = 6 total oz
leash plug and fin system = 4 oz resin 2 oz hardener = 6 total oz
Gloss coat repeat hotcoat above.
I have very little resin hitting the floor.
Use 2 hand fulls of resin per 100 square inches of surfboard.
Mako’s volumes will give you plenty of resin. Don’t mix too much. You can always mix up a smaller batch to finish up if you need to.
NOTE: Make sure you measure your 2:1 ratio exactly. This gets tricky with smaller volumes… Many guys measure by weight (45:100) for precision.
Yeah if you're worried about having enough, go with Mako's. That'd be plenty.
Maybe my math is off, or my lams are too dry, but 15 oz seems like an awful lot of resin for a single 4 on a 6'6". I'd have used 7 or 8 oz.
A sheet of 4oz. cloth 6'6" x 24" weighs nominally 5 3/4 oz.. Mako's volumes net you 3:1 resin to cloth ratio.
With the epoxy I use, I'm under no time constraints so if i'm a little dry somewhere I can always mix up an ounce later. This time of year I've got a 8 to 12 hour flip time.
When mixing smaller volumes use smaller graduated cups for acuracy. HomeDepot carries the quart size cups only, so try your local automotive paint supplier for the smaller ones ( I found some 1/2 pint cups really cheap). This is also your best supplier for quality tape and sand paper, my local guy gave me some pigments to experiment with when I asked about them. Get to know them, they are usually good people and will support your efforts…
HTH…
For smaller volumes forget mixing cups alltogether. Get a pair of syringes. If you can't get them from a medical supply West Marine sells them as do many tackle stores. Tackle stores carry small ones used for mixing the Flex Coat Epoxy finish used to coat the wraps on fishing rods.
Hi @don53,
I’ve created a resin calculator that can probably help you with this question:
Check this post:
1 Like
Does the resin number include the hardener.
Regards
Fantastic.
Especially for those not in US who can’t now access the greenlight website.
@Chris4 here is a 2015 version of the Greenlight chart, looks like they are going to roll out an interactive one as well. If you dig around on Sways you might find a version switched to metric units.
Surfboard_Glassing_Resin_Amounts_Per_Board_Length.pdf (1.5 MB)
PS I normally start with the weight of cut cloth in grams as the starting weight of mixed epoxy for lamination like @Hans mentions in 2010 above. If you are not doing color work, you can mix a little less and make a ‘shot’ at the end if needed rather than have too much extra. Little bits of extra mixed resin usually goes to fill craters in my concrete garage floor.
Thanks.
Quick question: if you use Volan should you add more resin.
Say: add a multiplier like 1.15 (extra 15%).
Regards
I have never added extra for Volan other than accounting for its cut weight. Laminating over wood and fabric inlays will take more resin. Fill coats take less and and gloss coat will take even less. I’d rather come up short and make a little more versus always having extra and trying to find something to do with it or risk having it exotherm in the cup. Some people do start a cup or other mold for dumping extra resin in the hopes of making tool handles or planer knobs, if their garage floor doesn’t need it.