i know that Bert Burger uses only epoxy resins, you might want to send him a message. he helped me out with an epoxy based question yesterday and seems to know alot abot epoxy. just wondering, where did you get your epoxy and how much did it cost you? i found a site on the internet where i could get 1 gallon for $60, but still looking for a deal. you also might want to checkout a june 30th thread entitled “Polyester or epoxy for balsa” i dont know weather your board is balsa or not, but either way it could help some.
I don’t actually have any epoxy …it’s Grant [“Hicksy”] who uses it . He uses the west systems , but today when he glasses his "Moonrocket’'s bottom , he will be using some different stuff [‘araldite’ , I think he said ] So , I’ll be watching closely [as well as photographing , of course]
There is a place here called kirkside who supplies . But I notice you’re in San Diego . I’m in west australia so that may not unfortunately be much help to you .
I think Grant paid $65aus a litre for this stuff he’s using to glass the rocket .
Who here uses epoxy resin when laying up fibreglass fin panels , please ?
I wanted to make one in the future, and was wondering : -
what sort of gel time ,
very temperature sensitive. Keep it warm (80F+) and it will cure completely in hours. Days at 60F. Depends on the epoxy, too.
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how tints go with epoxy resin ,
and also pigments ?
Pigments are the same as polyester, dunno bout tints.
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Also, sanding and foiling …any harder than with polyester ?
Pretty much the same, only less stinky.
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Are there any major differences to using polyester for fin panels ? (apart from maybe different gel time and less odour ?
You don’t finish with a gloss coat over the epoxy. I use an epoxy hotcoat with double additive F and finish sand it. With poly use a gloss coat. Also, with epoxy it is alcohol alchohol alcohol for cleaning everything including tools - with polyester it is acetone acetone acetone. Also, the epoxy sorta hardens slowly and evenly, doesn’t really gel like the polyester, but that doesn’t seem to matter much with fin layups anyway.
Seems you should be able to find a computer supplier and get some G-10 material, epoxy/glass in sheets already made. Might be easier for you, since it’s circuitry material for the insides of older computers, more availible close to Asia.
If there is a local Aussie/Kiwi fin maker, he can put you in touch or sell you some also.
Around here, Rainbow, TrueAmes, Finworks, and Curtis by the sheets premade.
I checked out hicksy glassing his moonrocket today …
With two batches , he was able to do the bottom and the rails and wings [and a groovy laminate he printed] , and he had nearly two hours working time .
It was around 27 degrees C [about 80-85 fahrenheit ]. It looks nice as he was able to really take his time .
Blakestah , do you know if pigments ‘bleed’ into each other a bit when doing a multicolour fin panel with epoxy , if it doesn’t really ‘gel’ in the way polyester resin does ? [because I WOULD like to do another multicolour panel or two, this time in epoxy , since I liked the look of them when I did them with polyester resin previously.
Pigments are the same as polyester, dunno bout tints.
I thought there were special pigments for epoxy resin? Is this true?
Well, the pigments used for polyester work fine for epoxy. If there are special pigments I dunno, but the little plastic jar I have says it is used for pigmenting epoxy or polyester resin.
If you want a good multicolor layup you always need to allow a complete cure between colors.
if you want a good multicolor layup you always need to allow a complete cure between colors.
So Blakestah, really would I need to allow two hours roughly , between colours , in the present 80 degree temperatures ? [ie: with four different colours in the fin panel , 8 hours ?? Polyester DOES have its advantages, eh ?]
Does an epoxy resined fibreglass fin panel become as hot or hotter than when working with polyester resin too ?
If so , I’m just wondering what is a good container to mix the stuff in ? [with polyester resin , I presently mix it in a medicine cup type container [30mls at a time].
Thanks Blakestah and any others [Bert? I 'p.m.'d you mate !]…any help gladly received .
yea sorry chip , i dont really use epoxy for laying up panels , i dont lay up panels at all actually in a conventional sense , so i didnt think i had any worthwhile comments to add to your question …
im real particular about weight and flex , so everything i do is with shaped fin cores and outer shells , im looking for positive bouyancy in fins , thats the main reason i dont do lay ups …
sorry for the delay , been hell busy and just droping in for short visits , if you hadnt sent a pm i probably wouldnt have checked this thread …
ok hope it works out …
hey did you get a wave yesterday ? finally the drought broke…mid west coast summers ?? this was one of the worst i can remember …
hey chip, i have used epoxy to lay up fins and it has worked fine for me. I only used one pigment so i dont know if i could help you there with pigments bleeding or anything, but i foiled the fin using a file and a belt sander and it looked good. For a gloss coat i just brushed epoxy after foiling and it came out looking nice. If you have any questions, feel free to hit me up, even though i am certainly not a pro and do not have much to offer. On curing time it was nice because i was able to take my time and make sure there were no air bubbles or anything, i also used a plastic spreader.
Don’t ever tell me that epoxy doesn’t stink. It may not smell much but gees I can taste the hardener.
Anyway, My first batch of 300grams went off in 1.5 hours. Sitting in a 500 gram Margarine container. It ended up getting quite hot but not enough to burn through the container.
This Araldite stuff is still pretty much unknown to me as yet, but it worked OK for me.
It cost AU$65 for a 3 kg pack mixing at 2:1. After doing a 8’10" board in 2x5oz both sides I still have half left. No too bad, still have to put a gloss coat yet.
Ben, I imagine that you could lay up several fin panels at a time and premix your colour batches without the hardener then stagger the application times. When one layer gets tacky it probably wouldn’t transport the colour through to the next layer.
yes Bert , 6 HOURS today ( [!!] I’m MUNTED now ! ) …got heaps of waves at my local .
The bonzer bottom is very fast , and I found myself making waves that surprised me …STOKED !! Only head high on the biggest ones , but still PLENTY fun !! You know those days when you just seem to jag it ? Well, my turn , for a change … stoked too , because we were pumped to surf after watching 'Riding Giants ’ on the big screen last night . [Go see it , if you haven’t already …a GREAT , movie by the same Stacy Peralta who brought us the memorable “Dogtown/ Z-boys movie” [thanks again Luke!]
Yes , I too want to do some foam and some wood core glass fins , for the bonzer. As it is the lightest board I 've made so far , it will be nice to make a set of light strong bonzer runners and a matching back fin for it , as well as the glass ones I just have to fine tune now…
When I get around to buying epoxy , I’ll let people know how I go with multicolour fin panels , okay ?
I’m on the other end of the spectrum. The cold one. Never a problem going off too fast, never gets that hot. But I wait overnight for multiple colors. A good heat room would help me be a lot faster, but I haven’t done it yet.
The epoxy I use is Resin Research epoxy. You can mix a batch in a room full of people and no one would know. The faint smell of the dust during grinding is milder as well.
Use mixing cups for measuring instead of a measuring scoop. One use, throw it away. If you use a measuring cup you’ll end up with some stuck to the sides, and it will throw the ratios off. And, unlike polyester, if you screw up a batch you are hosed. Something like this should be at a hardware store or resin supply place near you.
thanks Blakestah for that ! …especially for the cups and epoxy accessories link . Although I’m in Australia , it’s good to see the kinds of things available in America . You’re in San Francisco , right ? A bit colder than Perth , I’m SURE …our winter temperatures , a “cold” day here would be around 9-12 celsius [ about 48-50 Fahrenheit] . A lot of the time , it’s more like 18C [about 66F]
Yeah , Hicksy’s Araldite stuff stank , actually …I had a headache for the rest of the day . [… RESPIRATOR !! oops] . The West Systems will do the job for me …especially if I will be tinting or pigmenting it.
Bert , what epoxy do you use , please ? how’s the smell ?
What sort of weight of epoxy should I use per 8x10" fibreglass sheet layer , I wonder ?
[I was using 50mls of resin per 5 layers of 50z flatweave with polyester .]
THAT’S the other difference , I guess ? [having to WEIGH the liquid, rather than measure in mls [‘ounces’ for you Americans , I guess]
Anyone got any ideas / remember how many ounces of liquid [epoxy] you use , and tell me for how many layers of cloth [what oz cloth?] at a time you lay up , please ?
Yep , San Francisco, too close to the water for warm temps.
Anyway, I use little less than a quart for 36 layers of 6 oz flat weave. Quart = 946 ml.
Working in reverse, 5 layers of 6 oz would conservatively be 135 ml. But I do 13x13 layups, for an 8x10 it comes out at 64 mls. And, I’m a little conservative, and using 6 ounce, so you can probably start with 50 and maybe even use less. But it is not hugely different than poly in resin to saturate a fin panel.
The biggest diff is that the epoxy likes to soak in with its own time course, the poly you can force a little. I throw down the resin, squeegee it around, add new layers, roll, wait, roll again, wait, roll again, go to next layers.
thanks a lot for sharing this stuff , Blakestah [Dave?] …this is very helpful !!
Do you find you need to allow a little resin when pigmenting the layers or not ? [I guess epoxy is a little more runny perhaps than polyester , though , so maybe not ?]