Electric Bicycle with a petrol range extender

I think electric bikes are great, theres nothing greater than whizzing somewhere on one until the batteries go flat. So I figured I could use off the shelf parts and knock up my own prototype vehicle.
After some trial and error, more error than trial, i've come to point where I am satisfied with my efforts and want to share it with the world since I've not seen many other people fuse this simple idea into reality.

I took my standard bicycle (£100) and added an electic motor kit (£250), plus sealed lead acid battery 12ah @ 48v (£90), it is great as is and can acheive 10miles with combined cycling, now that's not enough to get me work yet alone home. And I assure you upto the 12th mile this was very arduous with 20kg extra weight and flat batteries.

So I picked up a cheap bicycle trailer (£30) and a cheap petrol generator 800w from aldi for £70. The problem here is howto to tranform the mains voltage to something that the bike controller is happy with, and theres over current protection to think about also. I initially thought about using a stepdown transformer but they are expesive and hard to get at the spec i needed. I tried an arc welder, but the voltage was a little low and the current too high. I could rewind it a little but I want to get results fairly quickly, so I instead opted to use regular computer PSU used in parrallel to get the voltage needed, plus they were rescued from the skip.

The biggest problem is the motors inrush current ~35amp, the psu's I had were max 18amp, so they would go into protection mode and shutdown. I originally wanted to use the power from the generator alone, but because the psu's kept tripping I added in the battery as a buffer. I could use a resistor but the commercial products would cost hundreds (needed 3.3ohm 1080w), so I used some springs as resistors, they will probably get hot and possibly melt, I'm hoping they last long enough for me to assess the range gain I can get.

So thats where i'm at with this idea, it's not pretty or efficient this I know. My first run was 8 miles with a battery at 50v which dropped to 47v, at that point I had no bridge rectifier or resistor, and I suspect the battery was being drained first, as i was only using 4 psu's 48v.
I suspect now that the source with greatest voltage will be drawn upon first, and without the resistor on my now 5 psu's 60v it would shutdown a couple, but now it draws from the psu upto 15-18 amp ensuring they all remain on and then draws upon the battery for another 7-9 amp.
I'm thinking of adding some big cap's after the resistor to provide some burstable current as really I want to be able to operate in 3 modes, Engine Only, Battery Only and Both.

Hopefully the storm will be over and tomorrow I can get some stats.

I have a couple of videos here;
http://www.youtube.com/watch?v=rxvo0Wz3Umo
and
http://www.youtube.com/watch?v=b2WinTF1lVg

Where i'm ultimately going is for a custom tricycle like a velomobile, and an electric start generator with a custom winding so I can do away with the 4-8kg of PSU's, maybe mod the engine with HHO or a fuel vapouriser, and possibly think about a huge joule thief for auxiary lighting, and perhaps smoothing caps, and I could think about regen braking into a super cap bank.

Thats it for now, and thanks for reading.

Reprap Mendel 3D Printing Lesson Learned

Having started my fascination with 3d printers back in 2011 when an associate showed me some youtube vid's, I was completely mesmerized by how cool they were. Then I would dream of all the things I could make, then the things I could design, and blah blah blah then metal printing and so on.

So that was it the Idea had been seeded and I decided to plunge into something I had absolutely no idea about or even where to begin. Having done a bit of search engine revision wolf strapping had caught my attention, so that was it I spent one weekend with a pile of wood some draw runners and knocked up 2.5ft by 2.5ft by 2.5ft monster of a frame. And the following week my large stepper motors had arrived Nema 24 I think, fist sized anyways. Then I got some pulley/cogs but they needed boring out, needless to say I did this unfortunately not in a straight manner! I was so excited I just wanted to click my fingers and it would be built! Anyhow I'd got this contraption to a reasonable state and with the Makerbot electronics I'd ordered I had one heck of a time getting the machine calibrated just for correct axis movement. It was quite exciting seeing something I had built in motion, Computers tend to be rather static!

It wasn't until it was built to this point that I realized why the wolf strap never really had any descent documentation, It was a bad design especially exasparated by my over sizing, The Z axis would flap 10-20mm. So ok I made a mistake and it was time to move on, So this time I ordered a reprap mendel frame, of which my nema 24's wouldn't fit so I ordered the right motors and hey ho onto the next stage.
Hotend design, still in my rep strapping idea I made a hotend from fire crete and some brass tube I threaded and a heatsink drilled and tapped, I kind of got it to work a little but staying at temp was an issue, eventually I got fed up and ordered a parcan hotend, much smaller than the one I made lol.

So my next problem was getting a decent print on a makerbot driven mendel using replicatorG! I think this was my biggest mistake, but anyhow I took to IRC and asked lots of questions but no one would help someone with makerbot tronics, fortunately scribbleJ was great, so i'd loaded sjfw onto it ditched repg and used pronterface! I was in business finally, prints were coming out quite good, even got a few upgrades printed, then one day it wouldn't print. Boy was I pissed, I mean I had many moments when I thought about just tossing the printer on the floor, but that day was the worst. printer finally worked for what seemed like 5 mins then the extruder fried...... something I should chase reprap.me up for actually!

Well what you'll find is 3d printing can be like this alot, one minute fine the next a problem! so given the lack of support for MB stuff I was looking for the next best tronics I could get, now not being to adept at this hobby I applied computer buying logic...... go for the biggest number init! so I ordered a Gen7 kit off ebay, built the thing then spent months trying to get it to work. I would have a couple of problems in teacup then in sprinter the problems would switch somewhere else. but in anycase between the two all hardware was tested as fully functional so no my soldering was not the issue, any way I binned the gen7 and ordered a sanguinololu 1.3b and the ramps 1.4 i think, which could be used with the arduino mega I had! I did this to be sure I could get my printer working again. fortunately I chose the sanguino to try first and touch wood it's been brilliant since!

Oh I forgot to mention Use the best oil you can buy and oil daily for best results. seriously I had major issue on my z axis until I used a decent oil