Demonseed Rebuild - custom CF deck, SRB trucks, 12s7p p42a, 6380

There’s a group I ride with that does track races and speed runs in the city. The majority ride a mixture of LaCroix boards, Kaly, Metroboard X, and DIY. I want my first DIY board to keep up with this class of esk8, but I’m keeping expectations low. The Demonseed deck was appealing for its wide stance, stiffness, and low height. I really like how wide the MTB style trucks are but needed something in the longboard format so I went with the Boardnamics 270’s, the BN mounts seem nice in my non-expert opinion.

The Torqueboard pneumatics seemed like a good place to start and easy to source when I need replacements, and at 6.3” they just barely clear the deck using the wide trucks.

I have 30q’s on the way and a Kweld along with 0.15 x 8mm nickel strips, fishpaper, etc.

Ordered a smart bms from - it’s been a couple weeks and I haven’t got a ship email yet so I’m a bit concerned that this may hold up the build (ESC’s too, but I’ll get to that)

Ordered the Torqueboard 6380 190kv, my initial thoughts were to go 18:62 pulleys, but I would have to source longer belts than TB supplies. 16:62 should fit off the bat but this is something I want to experiment with.

I’m also waiting for the TB v6 ESC to drop, but with Stormcore around the corner choosing an ESC is pretty difficult. I think I might try out an older model like Focbox or the TB v4 while the new hardware gets real world tested before making an upgrade.

That brings us to today’s first DIY sub-project and progress photos.

I thought I’d get my hands dirty (and sticky) with fiberglassing an enclosure myself. I picked up some surfboard polyester laminating resin along with 1.5oz mat and 7.5oz E-cloth from a local surfboard supply shop.

I cut some foam board to shape, 15 degree incline on the sides, 25 degrees on the end, and rounded the edges with a palm sander.

Hot glued and clamped the plug onto the board, filled in the gaps and created a fillet using plasticine clay.

Then I Wrapped the plug with more painters tape and waxed it using partall paste and sprayed on some PVA. It was hard to spray the PVA using my crappy paint gun so the layers were not as uniform as they should have been.

In hindsight that “reinforcement” strip caused way more issues than it was worth. 4 layers of this mat came out plenty stiff by itself.

Next came the actual layup. One thing I was fighting the whole time was it is very difficult to accurately measure the catalyst to resin (by the end I realized you can use a plastic straw as a dropper) so the layers tended to tack up much faster than I would have liked, later you’ll see that the first few layers are a bit rough while I was figuring out how to work with the material. I went with 4 layers of mat and one final layer of cloth because YouTube taught me that mat tends to conform to shapes better, which may be true with lighter mat but I found surprisingly the cloth formed much easier to the plug without wrinkles at the corners. Next time I think it’s better to sandwich the mat between cloth first and last.

Lastly one thick layer of gelcoat applied using a brush.

The next day I was able to separate the glass pretty easily using a plastic wedge. You can see some gaps in the first layer where I either didn’t dab down the mat well enough or it ended up pulling away as it dried, which fucks up any subsequent layers. I filled in these gaps with bondo.

Later came time to shape the glass, I cut out the basic shape with a cutoff wheel then rounded the edges with a flap disk. Did this outside with a respirator, goggles, and shopvac nearby to remove what dust I could. The previous gel coat was still a bit tacky and gummed up the sander pretty quick. I did my best to sand off the tacky bits and lumps until dry and applied another layer of gelcoat.

The next day the gelcoat is still tacky. According to some boat forums this is likely due to improper catalyst ratio. This application was probably fucked but I wanted to try salvaging it anyway, just see if I could. Some suggestions they had:

  • time: let it cure for a couple more days

  • airflow: use a small fan to keep air circulating over the part (not sure if this is correct, everything I read says oxygen inhibits cure)

  • not-airflow: layer on some PVA to block out air

  • heat: attack that bitch with a heat gun

  • if all else fails strip it with acetone and try again

I went at it with the heatgun for 15ish minutes and let it sit for a couple hours. did this three times, felt like the tackiness reduced by half but I could still leave fingerprints in it, so I sprayed on a thick layer of PVA and let it sit overnight. After washing it off the situation had not improved I said so fuck it, time to strip. The gelcoat came up pretty easily using acetone and a plastic scraper and the resin underneath had cured so I took the opportunity to sand that.

I was pretty happy with how it turned out with a few hours of hand and palm sanding. Still a bit lumpy but I thought a final coat might even the low parts out. I mixed in some midnight-blue mica pigment with polyester finishing resin and let that cure overnight. After a half day of wet-dry sanding from 400-1000 grit I think the result turned out ok, if a bit ugly. Still lumpy in parts and the clear coat did not layer on evenly, but I think it’ll serve as a functional part.

I’ve got a few days before the battery making supplies arrive so I think I might try another hand layup, having gone through the process once I think I can do a better job on the next iteration. I want to do more research before I buy equipment for vacuum bagging eventually.


Good build, keep it coming


Love the enclosure! Let me look up mine, did it nearly exactly the same as you!



Quadruplets :joy:

Nice work so far bro!


I’m digging the maroon color, and nice finish on your enclosure! Great to see that it works.

Wow, what a pro finish! Interesting choice to glass over the pass through, did you need to raise the clearance?


Its a saga dude :sweat_smile:


damn dude nice work, I really like those glass plates you make.

1 Like

What date did you order your BMS? Also nice work m8

6/23 paid for the fast shipping, hopefully they’re not on lockdown or something. Your hummie build looks pretty similar too, nice battery design. What do you think of the Maker X?

Yeah I’m waiting for some things, one of those being the BMS, but I ordered it yesterday so I wouldn’t expect it for a while. There are somethings from Ali express that I need too (charger, heatshrink, some things) that will take a while. Not in a big hurry yet

6/23 huh that’s only 7 business days, not too bad yet.

I think my Makerx dv4 is great so far, no comment on the one for the hummie yet since it has not been powered on yet. By visual inspection I have no issues with the PCB though haha

1 Like

Great enclosure work!


nice work with the enclosure!
dis gonna be good

Couple of minor updates: I wasn’t satisfied with the finish on the enclosure last time so I sanded it down and applied another thin pigmented polyester resin coat which came out much more uniform. Calling this one done minus drilling for the machine screws.

I’ve got a bunch of fiberglass materials left over so I thought I’d try a negative mold as a side project, taking a page out of @glyphiks book

¼” ply and ½” ply to conform to the shape of the deck, sanded the top then clamped one more layer of ¼” over that to smooth out the undulations in the first two layers.

independence day margarita

shaped the plug then filled the gaps using fumed silica and sealed using several layers of polyester resin.

to be continued…

Back to the main build: after assembling the kWeld I started on the battery. Here’s the first P-group, hot glued together and welded 0.15 x 8mm pure nickel (no sparks when rounding off the corners using the dremel, good sign)

37J seemed like a good setting for the nickel-on-cell welds.

The folded-over bus bar seemed like one of the cleaner options for a flat pack in this configuration. I’m planning on soldering two or three 14 awg silicone wires for the series connections.

missing the negative bus bar, 26J still seemed a little hot for nickel-on-nickel welds.


Looking sweet bro!


from afar it looks like there’s a subtle camo pattern on the enclosure

These homemade enclosures are sick


Looking brilliant dude :ok_hand:

What’s ur power source for the Kweld? Presently building mine and will be running 2 X 5000mah graphenes in parallel.

just the one, I’ve only started using it today so I can’t honestly say whether it’s enough Ah or not. I seem to have an issue with blowing holes in the nickel rather than under-welding them :laughing:


Good to know. My impression from reading a ton about it is that 1 is def plenty of juice but 2 in p will have much longer lives cycle-wise. Watching the build w interest, dude. Good luck :call_me_hand:

1 Like

Are you using the probe holder? If you are, take it off and throw it in the closest bin :+1: