Nagini | Build Journal

[That_Jamie_S_Guy]

Who’s ready for more dumbfuckery?

With the enclosure on, I took Nagini for a test ride yesterday despite the dodgy motor mount clamps.

Where I switched over to BN hangars, my clamps are now too loose. I have a friend machining me some new ones, but in the meantime I figured if I just shove a couple of washers in the gaps and pray it will do the trick.

One of the mounts fell off mid ride (luckily just as I was slowing down after testing top speed…) and I lugged her home to inspect the damage.

As suspected the washer vibrated loose. I figured I could drill a hole in the clamp, tap it, and use a shitty grub screw style adjustment to temporarily use the motor mount.

It went well, but I know it won’t last long.

The other mount was holding up just fine, but that washer wasn’t exaclty inspiring any confidence so I decided to do the same.

I lost focus while counterboring the hole with a 6mm drill and accidentally went through the full depth. Fuck. I don’t have any M7 screws I can use. I decided to try drilling a hole from a different direction. The drill bit snapped and is now stuck in the clamp…

Despite my best efforts to drill it out, all I ended up achieving was blunting my drill bits so they’re now totally unusable.

I then had a brand new sharp idea. Why don’t I just use gorilla glue and stick an M6 screw into the 6mm hole? If I secure it just past where it needs to be, I can file it down to acheive the right length once it’s in place, then use the proper clamping mechanism to secure the clamp to the hangar.

This is the only M6 screw I have. This is a total shit show destined for disaster but my own morbid curiosity is keen to see if this works…

[That_Jamie_S_Guy]

Logged a small portion of my commute this morning in Strava.

Hit a top speed of approx 25mph which I’m very pleased with! I was riding very conservatively because it was wet out, enclosure hasnt been fully waterproofed, my 3D printed 60T pulley is starting to wear, and I have less than ideal confidence in the motor mounts…

My commute consists of this section, an hour and a half on the bus, then another shorter but more hilly stretch. I’m going to start posting my stats after each ride to see if things change over time.

Typically if I get the bus, this stretch takes about 10-15 mins. Usually I skate it, and it takes 15-20 mins. So already seeing some time saved!

[That_Jamie_S_Guy]

Much nicer conditions this morning. Sun was shining, ground was dry, and I only got stuck behind one cyclist.

I need a horn. I’m thinking one of those comical looking clown ones you can get for a bike but activating it would be difficult. Foot press is out of the question in case I need it at speed, so I’m thinking of attaching something to my puck.

Anyway, enjoyed this little ride. Hit a record speed of 28mph and would have averaged higher if not for this photo opp:

I’ve realsied I can’t break suddenly without hearing/feeling a knocking sound. It sounds like the belts, but I couldn’t see anything while riding. I’m probably getting some slippage due to the small motor pulley, large wheel pulley, and small centre distance. In my next revision of the motor mounts I will be including an idler mounting hole in case it’s required.

[That_Jamie_S_Guy]

Also on a side note, does anyone want to send me free Esk8 stickers?

Woukd like to build something of a collection to cover up the scars of riding off a fat curb by accident without realising it was there…

[rosco]

Dude, the fit and shape of that enclosure looks great
It’s a massive amount of effort, but super satisfying to complete and have it fit everything properly.

[That_Jamie_S_Guy]

Thanks man!

I am incredibly happy with it, but the pictures don’t tell the full story.

There are some gaps around the edges I need to seal with butyl. Also, the flange overhangs the deck by a couple of mm in some places and is too small in others. The chamfer isn’t consistent and the wall thickness is all over the place.

Not bad for a first attempt though, and I’ve learned a hell of a lot from it.

[Venom121212]

@That_Jamie_S_Guy

does anyone want to send me free Esk8 stickers?

I got you homie. You deserve it for tackling the fiberglass demon. Pm me your address and I’ll ship you a variety from my collection.

[Common_good]

@That_Jamie_S_Guy

hearing/feeling a knocking sound. It sounds like the belts

Ya, this sounds very much like belt slipping to me. Too large a ratio could def be the culprit as the pinion would not have enough teeth on the belt at any given time and hard braking would cause slipping. This would be exacerbated by a short center–>center distance. You could move to a slightly larger pinion or, if your mounts allow for it, utilize an idler to bring more teeth into contact with the belt. It could also be that you’re running your belts too loose. What ratio are you on?

Edit

Just noticed this:

@That_Jamie_S_Guy

my 3D printed 60T pulley is starting to wear

This is likely causing the slipping. Get yourself an alu pulley.

[That_Jamie_S_Guy]

Know of anyone selling alu pulleys for bergmeister wheels?

I was going to try my hand at Nylon or some form of composite material.

Pulleys are 16T and 60T

[Common_good]

@That_Jamie_S_Guy

I was going to try my hand at Nylon

Glass filled nylon would be much more robust and has been used with success in past iirc. Berg pulleys are a tough one to find but I’m almost positive I saw some in the parts market not too long ago. Do a search and see what’s around? Alternatively, if you wanted to upgrade to gear drives I have a new set of Berg adapters dor BN M1s that I’m almost certainly not going to use…

[That_Jamie_S_Guy]

Don’t tempt me like that…

Will see what I can do about the pulley but if all else fails I might go for the gear drive.

[Common_good]

Lemino!

[That_Jamie_S_Guy]

So I’ve finally got some time to work on Nagini today.

For the last few days I’ve been completely unable to bluetooth into the pack. I assumed it was just the app playing up, but after reinstalling and no luck, I became concerned of something more sinister.

When I last ran the board, it was a hot day and I could feel my voltage cutoff coming into play to slow me down where I hadn’t charged it fully up before leaving the house. Not knowing the voltages for a few days but knowing it’s low has been a bit scary…

Anyway I just opened up the enclosure and the BT module is dead. No idea why. No visible damage and it was secured to the pack with duct tape. Checked over all the wires, no bare wiring. Luckily I had a spare BT module from the spare BMS i bought after blowing the first.

Instantly reconnect to the board.

Luckily everything seems okay but I’m worried about why my BT module went. Any ideas?

[That_Jamie_S_Guy]

Cable glands in, to provide better waterproofing.

Currently fighting with butyl tape. This stuff is a bitch.

[That_Jamie_S_Guy]

Testing Nagini’s offroad capability today.

I was feeling rather ambitious and hit some gnarly chalk hills that are a 5min walk from my house. The views are incredible here. It has always been my dream to Esk8 these from the moment the concept of Nagini was born. Here is the view from the top:

Given that I’ve never even used a mountainboard, let alone an electric one, and especially not a board designed for street on rough terrain, I was planning to go fairly conservatively. That didn’t last long, I was having a blast.

My first hiccup was when I came through the tree lined path and got to the fields. The fields are on a very steep incline, with lots of rabbit holes. You can use your imagination to guess what happened when I hit one.

Past the first field is where the crazy chalk hills start and I was looking forward to testing the limits here. Went fairly slowly, and managed to stay on the board despite the gravel, the cow pats, the pathways only just wide enough for Nagini’s wheels, the thorny bushes and the hidden “curbs”. I got to the second field.

Absolutely RAGGED IT through here at a stable 15mph despite the poor traction through the field, and down the gravel track to the end of the path. Got to the end of the path (yellow) and decided to try going uphill (turquoise).

This was a fucking nightmare.

Super steep.

No traction.

Constant incline in both directions.

Loads of pot holes.

I had to walk the entire turquoise stretch and I can tell you now it was NOT easy or fun to lug Nagini through all of that.

Here’s a candid picture I caught of Nagini longing for ATB tyres:

I decided to attempt the decent back to the start of the chalk hills. Way too steep and too close to a very vertical looking cliff face. Stacked it a few times to the amusement of onlookers, and decided to go back down the chalk path (Blue).

My legs were a bit jelly this time so I came off the board once or twice. Nothing serious, just hopped off where I hit unanticipated obstacles. Got back to the field and went even faster this time.

Took a nice video of Nagini in action. Will upload it here once I’ve cropped out the heavy breathing and poor camera angles…

Decided to hit the dusty gravel path (green) to the cycle path (white). This was super fun. A short stretch, but a nice wide path, good visibility, nice turns and good traction. Stopped at the end for a bit to chat to someone who was interested in the board (definitely not because I almost went into a gate post)

I realised the time and needed to get home quick to make dinner for my Fiancé and I, so I went as fast as my jelly legs could handle. I was keeping it under control, and again being fairly conservative so I didn’t expect to top 28mph (previous PR). However I managed to hit a whopping 33.4mph, with plenty of coal left for the fire!

Really enjoyed this route and I might make it a routine after work activity to go through the chalk path for some ATB action then back down the cycle way to get some speed. Challenge myself hit a PR for the entire route.

Don’t let me forget to cancel my 30 day free trial for Strava though…

[That_Jamie_S_Guy]

New video by Jamie Searle

[glyphiks]

Sounds like heaps of fun! 4wd mtb next?

[That_Jamie_S_Guy]

With an upcoming house move (with a shed that needs turning into a workshop!), 2 broken 3D printers to repair, one half built 3D printer, a desperate need to build a mini mill, a CNC router, and a desire build/buy a lathe, Unfortunately a 4wd mtb isn’t gonna happen for a while…unless I win BOTY of course…also I want to build a onewheel before my next esk8 project.

In the interim I’ll probably end up chucking some ATB rims and tyres on. Maybe even replace the whole drivetrain but certainly not in the immediate future.

[That_Jamie_S_Guy]

Took Nagini for a spin this morning.

The ground was a bit damp, meaning I couldn’t get any traction on the slightest of inclines on the grass.

On the way back down the cycle path I tried to max out my speed. I realised my front foot was too close to the wheels so made a slight adjustment which threw me into wobbles at 30mph.

I was fully prepared and bracing myself to bail hard, but managed to slow down in time to recover. That was a close call.

This has highlighted the need for a foot stop too. I figured due to the drop down shape, that wouldn’t be necessary but my feet have a tendency to lside forwards as I ride given my positive stance. Grippier shoes would help too.

When I get paid I’m planning to get a cheap go pro knockoff to get some better ride footage.

Also I had an idea the other day which could hold some merit. I was fixing a puncture on my berg tubes and realised my bike saddle bag would be perfect upside down on the back of the board to store a few tools.

[That_Jamie_S_Guy]

@That_Jamie_S_Guy

bike saddle bag

Decided against using a saddle bag as I found this pouch laying around from when I used to be an army cadet.

It looks a little silly but…I like the utilitarian aesthetic