those anti switch have fuse , im fine with 60 amp right ? i dont want to 
my board
I would choose 80-90a if possible just because your battery can handle it and it is less likely to trip accidently
1 Like
True, but still, as a project I would like to make the mount myself. It’s something I’ve had decided from the beginning. I’ve also studied trampa’s mount before, but I didn’t trust the deviation I said the hanger caused on the mount. Using the crossbars might help though, I’ll wait for the company’s response and then decide on that.
Thanks for the input!
Whne you got your crossbar can you post it here , i want to see it 
i dont know if im gonna buy the trampa mount or mount from unikboard
Sure! I’ll try to post everything I can!
Go with the one from unik 
1 Like
Merry xmas to all!!
if im gonna use focbox unity do i need to use anti switch spark ?
nope
10char
merry Christmas to everyone. love what you’re doing btw! you defiantly need to change out those 3D printed motor mounts. trust me I’ve tried using 3D prints for high toque applications like that, see if there are any maker labs around your area, i found one about a mile away from my house and they had a CNC machine. also I would get some sealed 6374 motors, it will help you out in the long run 
where are you based? UK?
Merry Christmas!! Yeah, I wasn´t planning on using those 3d printed mounts for actual use! I´m requesting prices to different aluminium manufacturers around my city. I´ve been searching and there is not one maker lab around that isn´t my university, which, by the way, is full at the moment. I should have thought about that before buying these, but I have plans to partialy insulate them from road water and what not.
I´m based in Madrid, Spain!
have you tried 3d hubs? apparently they do CNC work now too
They do but they are bloody expensive.
Makerspace are good but my one for example doesn’t have people who know how to use it so you are forced to lesrn something that isn’t very easy/cheap
yeah fair enough
UPDATE (25/12/2018) Merry Christmas and happy holidays everyone! 2019 is aproaching fast and I couldn´t be more excited!
I´ve received almost everything I need at this point:
Focbox Unity So pumped!! I didn´t research enough about the connections though. I didn´t think there were so many types of JST connectors! Motors use 1.5mm and Unity uses 2mm JST connectors. Oredered some adapters from aliexpress (added to the item list). The 3 banana connectors on each motor are 4.5mm while the Unity has 3.5mm, so I also ordered those connectors to make an adapter.
I didn´t want to cut the motor cables so I don´t ruin the warranty, plus it´s better future sales!
Samsung Batteries
I changed my mind last second and decided to go full crazy-mode with 12S6P setup, 72 30Q cells in total!
I also decided to build my own spot-welder with an old microwave transformer and a relay. Got it working today. I just have to 3d-print some kind of levers to make it easier to use.
Trucks and motor mount
Finally got the hanger machined! Redesigned the mount so it has a snug fit while leaving a bit of room for movement. It will be fixed in place with M4 or M5 screws.
I´ve learned this really usefull trick from Wintergatan (you have to see his videos on youtube he´s amazing). Make small circled cut-outs on the corners so it fits without having to guess fillet size or tolerances!
And that´s it for now! I´m going to focus on finishing the motor mounts first before starting to make the batteries and test the motors. This way I won´t go crazy wanting to ride the board but not having the mounts yet!
I have exams in January so I thing I´m going to relax a bit till new years and then study for those exams, I won´t be advancing much till the second week of January.
Happy New Year everybody, see you in 2019!!
1 Like
I have looked but they charge me like 500 euros for 2 mounts, It´s just not worth it. Also, this aluminium manufacturer has water-cut machines with 0,1mm tolerance. This cutting process is so much cheaper than CNC machining. I don´t think they´re going to give me a price till new years though.
If I go that route the only thing I would have to do is drill the holes in the mounts for the attachments to the hanger and the crossbars, which isn´t that hard to do.
1 Like
12s6p! I hope you have a huge enclosure for that, and building your own spot-welder! Legend! you obv want speed with that 12s6p, ride safe man
1 Like
Hahaha yes! I´ve calculated the space in the cable chain and, with the top portion, everything should fit fine. Honestly, I was more concerned about sagging than top speed. But it´s a plus! I will always wear body-protection though and ride safely! I can´t wait to finish it!
3 Likes
Well hello there fellow people!
First of all here are the reasons for my 10 month hiatus:
- 3 of my battery modules cought on fire after my impatient dumbass wanted to test-fit them inside the enclosure without insulating them:
-
After that I ordered more batteries and more nickel strip which took a while to arrive. By the time it did I was already into my final exams.
-
I spent the whole month of july developing a homemade spot welder with a microwave transformer and an arduino (I know):
This brings us to October:
BATTERY PACK:
I finished welding all of the battery´s modules. I discarted my initial idea of spot-welding 3 nickel strips on top of each other because, as you know, nickel to nickel doesn´t really stick that well. So I left only one nickel strip and I welded cable on top of it just to be sure that conduction is good:
By the way, here´s a tip for soldering on top of nickle, if you sand the nickle it will stick SO much better:
After soldering all of the modules I redisigned my battery insulators (and this time I used them). Sadly I was so pumped to build the battery that I didn´t take pictures of how the modules look, but here´s the CAD version (I will leave all the CAD STL files at the end of the post in case you want to use them):
All soldered, shrink tubbed (is that a word?) and assembled, including the BMS, looked like this:
There are 6 modules in total (12S).
Note that I couldn´t fit the other 2 modules (4S more), so I put them on top of the board, you can see another enclosure in the image. Those 2 long black cables coming out of the center of the board are the connections for those 2 modules.
MOTOR MOUNT:
Redesigned the motormount.
Test fitting the new motor mount:
Note that the trucks need to be machined from two sides so the section is 21.5 x 21.5 mm.
The plates of the motor mounts, as well as the crossbars, will be ordered in 7075-T6 aluminium.
Separators will be the same as the ones you see in the video, they are printed in PETG.
The motormount works as is, all 3D printed, but I don´t like how much movement it has, so that´s why I´m going with aerospace grade aluminium, it wouldn´t be a beastboard it if hadn´t some of it!
FUNCTIONAL (but not finished) BOARD!!
So again, I was impatiend and I went for a stroll, I´m surprised as how resistant the 3D printed parts are, they haven´t bent at all but I´ll be ordering some this week.
Here are some statistics of the ride, bare in mind that my area has some steep downhills and uphills.
Next steps:
-
Order the aluminium parts for the truck mount.
-
3D Print some end caps for the enclosure
-
Waterproofing the enclosure as much as I can, although I don´t plan on riding in rain.
-
Make an emergency current cut-off loop on top of the borad.
-
Add some cool head lights I have to the board.
Well that´s it for now! Will try to finish the board by the end of the year (Hopefully won´t be another 10 months).
Troubleshooting:
This is for anyone that can help me with some of the issues I´m experiencing:
- With the board off the ground, I noticed that one of the motors would start before the other one and it feels like it has a bit more power. When I brought the board back to the workshop I undid the pulleys and moved the motors by hand. I noticed that the one that gives more torque has a more smooth rotation than the other one. I can feel the “magnet stops” a lot more on the other one.
While riding the board I can´t tell one of the motors is pushing more than the other, everything seems smooth.
Here´s a video, you can see that my hand shakes more while moving the right motor, making a kind of “stop stop stop” movement:
STL FILES
-
Motor mount: https://www.thingiverse.com/thing:3997552
-
Battery module insulators: https://www.thingiverse.com/thing:3997544