@glyphiks so if you are using epoxy you can’t use gelcoat right? Or does there exist epoxy gelcoat. What do you do in that regard? Thanks 
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I make my own gelcoat by mixing fumed silica with epoxy resin. Epoxy gelcoat does exist, but i’ll be fucked if i can find it in australia.
The fumed silica works brilliantly. And you can mix it to whatever consistency you like. I like mine thicc
Edit: i have tried several times using different methods to get polyester gelcoat to work with an epoxy layup and I haven’t been able to make it work.
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Cool - I might go that route. Though I did buy the polyester. Forgot the gelcoat so that might be a good thing in the end.
You tried to mix the two right? Gelcoat and epoxy
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Yeah i tried several times and failed. People have told me that it can work, but i couldn’t get it to work. It sticks, but it doesnt bond properly.
Know the feeling. Everyone else got the magic
Does the gelcoat stink as well. Guess it does.
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It surely does my friend 
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Might be a stupid question but why use gelcoat at all? As I understand it it’s “just” thick poly/epoxy. I know everyone use it but why?
Edit: maybe to avoid it from running on the vertical sides.
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I use it to give me a hard finish surface. And also to stop the texture from the fibre showing through on a finished part.
Epoxy resin is actually quite easily scratched and damaged. Adding the fumed silica makes it a lot harder and more resistant to damage.
It is also useful when you need to work the surface a little bit. Its a lot nicer to sand and shape than just epoxy alone.
It’s not just thickened epoxy, it is hardened, reinforced epoxy.
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I use it as a smart finish. You can do without it I would have thought, and just rub down and spray the part afterwards.
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Thanks Ben. Do you put it in the mold or paint it on afterwards? And maybe last question… Do you use poly or epoxy?
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I use polyester. I use gelcoat in the mould. Same process as boatbuilding. It’s possible to not use the gelcoat and just spray up the fibreglass part afterwards though.
All my resins are polyester based.
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Thanks Ben and glyphiks (dont know your real name ) Appreciate it.
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BTW I’m not much into enclosure building (yet) but work for a German dry morta and construction chemical producer (I’m a building material tester and development technician, so I do mostly “dirty” labwork formulating/testing new products or test what kind of materials different suppliers have to offer)
If anyone needs a small amount of fumed silica or other fillers maybe try to massage me.
Stuff I have (likely) laying arround:
- fumed silica
- glass (micro)bubbles and expanded glassbubbles
- differnt kinds of silicate minerals; which means different types of dry clay powder, talcum, (mica), …
- a few dozen kinds of limestone and similar stone powders
- clean dry sand/gravel from 25µm to 8 mm
- fine wood powder/fibers (also a bit of plastic and glas/carbon/“stone” fibers)
So if you need only a small batch (0,1 - 3 literes) for testing or 1-2 projects just try and leave me a massage maybe I have some on hand.
It’s most of the time no problem for my boss if I use some of that for myself at least as long it’s the “normal” stuff we have lying on the shelf. There are always left overs we literally have to throw a few m³ of different stuff in the trash avery once in the while).
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I already purchased the 40t cells and the largest 12s battery I can fit is 12s3p. I was originally going to do a perpendicular flat pack like the pic below but then I would have to stack the BMS on top of the battery or under the Unity. The board is already really low to the ground so I didn’t want to add any extra height and I didn’t want to have too much heat so I went with this design.
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What protective gear do you wear when working with that stuff?is there a special kind of respirator to use?
Protect your skin, always use in a well ventilated area and use a mask like this.
The clue is in my profile picture.
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Thanks I have been thinking about buying a good mask. I bought a cheap one and one of those RZ masks for dust but I feel like when I do stuff like spray paint or lacquer the fumes get through
Shave well and replace these every month. Work like a charm.
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