After 5 years of owning my electric car, its come time to say goodbye. The short story is simply that my original lead-acid batteries have reached their end of life and I can't invest the time or money into replacements. So, i've disassembled the car, which is going for scrap, and have the good EV parts here for sale. Anyone with interest or questions, please contact me at jboncek@gmail.com
Spring is here and so is the latest version on my electric skateboard! This winter, I virtually rebuilt everything but the motor assembly. Here are the abbreviated release notes:
Increased ground clearance Single switch on-off External LED status lights 4 screw service access Flush charging port New .75in 3D printed risers with integrated cable ties
Of all the improvements made this winter, by far the biggest and hardest in the list was increasing the ground clearance. But, I have to say...it freakin worked. Now the bottom of the box is just about level with the bottom of the trucks. I nearly doubled the clearance from 1.5" to 3". Riding on this box for a few weeks now, i've yet to bottom out on anything.
In order to accomplish this, I literally had to disassemble to motor controller, hack .5" off of the main terminals, drill new holes and get special low profile bolts. Then, because the tolerances were so tight, I printed an ABS plastic spacer that fits in the small gap between the controller and the box walls so it wouldn't short out with a sudden slip or bang.
But before I did all that I had to explore all the options with what I had. I disassemble the battery pack to see what was in there....I tried gaining clearance by splitting the pack into 2 halves, but there was not much to gain. I was able to tweak how the main leads came out of the pack.
Okay, so I decided how it's gonna go - now how the heck was I gonna build it? It seemed expensive and kinda dumb to sub this out to a shop, so I bought a bending brake for $75, and a sheet of aluminum off amazon supply (free shipping with prime :))
As shown in the pictures, I drafted my flat pattern, cut it out, bent it and then riveted it together. In the end flanges, I managed to have Steve install rivnuts so I wouldn't need to have access inside to box to the nut. Just 4 bolts. This was a very nice addition to the design and makes it a breeze to disassemble, service or reprogram.
Now it was time to get everything into place. I knew that the battery and controller were roughly fixed, but I hadn't worked out the rest of the wires and components. They were small details...Enter the wonders of 3D printing. It was super easy to layout all my parts and make everything I needed to get all the little parts right where I wanted them.
The picture should show the rest of the details: charging port, on/off, LEDs.
And here is the final assembly on the road!
Hope you like. Anyone with any questions , feel free to comment.
Its been a little while since i posted an update...and it was a busy summer indeed.
First, the board is riding great. Here is the latest video:
Since then, i've been working on a number of new projects, which prompted me to make the jump and buy my own 3D printer. As anyone in the market would do, i read up on all the reviews i could. I ended up going with my gut and getting the Duplicator 4 made by Wanhao, and i bought it from makergeeks.com
The only trick was there aren't much for reviews out there at the moment. But on the bright side, its specs are almost exactly the same as the Replicator 2 from Makerbot....but just about half the price.
The unit arrive 2 weeks after my order date, which was the minimum expected (2-3 weeks).
Unpacking went smoothly. It was very well packed and shipped. Assembly was 2 screws for the extruders and some quick twists to mount the filament spools.
The instructions themselves could have used a little help on the grammar side of things, but all-in-all I was able to figure it out pretty easily.
Upon startup, you're instructed to run through a pretty easy leveling process. 4 spring-loaded hand screws under the build plate level each corner. The program steps through front center, rear center, left and right, then center center. asking you to adjust the plate in each step to allow only a piece of paper between the nozzle and the plate.
The heated bed has some sort of thin plastic coating on it, which i got a scratch/tear in mine, probably from my alignment being too tight, initially. but it hasn't been a problem yet.
The printer takes .x3g files over USB or SD. i've been using the SD exclusively, and generating the files with Replicator G. Being new to all this, it took a few prints before i fully understood the variations and functions of each setting. But pretty quickly i caught on with what works and what doesn't. For now, i have 2 spools of ABS 1.75mm. Default settings have been best. 220C tip, 110C platform, 30 feed and 30 travel, although i have been successful with 50mm/s too.
The onboard software has a few nice features that i wasn't fully aware of, and might be of some interest. Today, i did a nozzle alignment, similar to a paper printers, where it prints a bunch of lines from both extruders and you pick which are best aligned. I ended up updating 1 axis by 1 point. The utility also includes the startup procedure script and a re-leveling script. The LED functionality in the menu doesn't seem to work however :/
Overall construction of the printer is excellent, from what i can tell. All the parts are solid, professionally molded (not printed) parts. aluminum gears, solid bearings, belt driven XY axis, with belt tensioners.
Not sure what else to say about it. If anyone has any questions, please comment here.
I will be demonstrating my electric skateboard at the Westport Maker Faire, on April, 27th. This should be a super cool event, and I'm really looking forward to it.
And....
Revision 3 is awesome!
Here is what changed:
Updated controller settings
New voltage regulator circuit
Reconfigured lots of wires
The results:
The board now rides like a dream. The wireless control takes you from a super slow creep, a foot per second or so, to full speed, in very nice increments -- easy to control, easy to hold a steady speed. This is what i'm most happy about. As noted earlier, there was some difficulty in this area, and i'm now fully satisfied with its operation. Win!
The voltage regulator now allows me to power the wireless receiver with the skateboards main battery pack. I had always planned on doing this, but in a rush to ride, i skipped this step and slapped a 9V on the Fio. It also took some work cause i needed a good VR to go from the 40VDC down to 5VDC. So I got this Recom switching regulator
All the wires are now hidden - with the exception of the leads going to the motors, which are very discreet. Nice and pretty.
Unfortunately, i didn't get to take a good picture of the board without the wires hanging out yet. But here is a picture of the voltage regulator circuit.
I went for a few rides around the neighborhood today, after the update. All was well. Tomorrow, I'll be heading up to Trumbull to ride with my buddy Tim, and his pedal power.
The next step will be to install my new F4 bindings I got. I can't tell if i'm going to enjoy them or hate them. It seems like a bit of a toss-up; But i am interested in having a little more leverage to use on turns.
Today, I managed to complete the assembly process and take Onca Onca out for her maiden voyage. A Total success!!!
Here is what the assembly looked like:
Tight Fit
All went almost exactly as planned. I had to get a new battery box bolt that was a .5" shorter. Aside from that, it was just a matter of putting everything where it belonged, filling the tires with air, and going for a ride.
At about the same time i was walking out the front door, my friend and neighbor Dom arrived, along with my neighbor Mark. We took turns riding down the street and around the block. They were ecstatic!!! I new what to expect, and had far higher expectations, but don't get me wrong, i'm super happy with the results. Everything was flawless. No chain issues, no wireless interference, excellent acceleration and deceleration....almost too good. All my new part, designed by myself, performed perfectly, and that is a really good feeling.
Here is a rundown of my mental notes of improvements for Rev 3:
1: Tune both accel and decel curves to be a little more forgiving on the early part of the curve. I may do it via code on the Fios or on the Kelly or both, but right now they kick in with some bite, but are still very usable!
2: Revise the remote to have a snap-together case with some more rigidity. It works great, but its on my TODO list.
3: Find a cooler deck.
4: Paint (or find an artist to paint) the bottom of the battery/control box.
5: Better integrate the switch(es).
6: Update it to use only 1 ON switch, and power the receiver via the main battery pack. (this fell of the table for rev 2 for the sake of importance and time.)
For now, Rev 2 is awesome. i'll likely put a little effort in to #1 and smooth that out a bit, but i'm not very concerned about the rest. Spring is almost here. I'm ready to plan a few longer trips, figure out my real range, and just have fun with it!