You see me rollin'

I finally got this monster assembled enough to roll it on its own. I mounted the rear axle on, slid the tire in, and with the help of one Nick Krywolpusk, we got it on the ground. It was really an exhilarating and uplifting feeling to finally be able to sit in the thing. I couldn't steer it, nor could I drive it, but it was such a great thing, to see something that I put together finally look like a vehicle. More to come.

On a side note, my PC's power supply decided to die, so it's "better know your Mac" time for me.

Done... ish

Done... ish
Originally uploaded by zzm634

Now that looks like it can go somewhere. I could have probably shown this at my presentation and said, "So yeah, I finished!" Bonus points if you can pick out the things that still need to be done.

It sure doesn't look like a traditional go-kart.

Things to notice:

• The back wheel is sitting above the frame when it will be mounted below when it's finished
• The steering wheel isn't actually connected to or supported by anything
• No chain or sprockets
  

Deadline

I gave my presentation for this project today. It didn't seem to go too well. I can assure you all that this thing is more finished than it looks. Stuff left to do:

• Rear axle
• Drill holes in pipe
• Line up and mount bearings
• Make spacers for rear wheel
• Assemble
  
• Mount seat
• Mark holes to be drilled
• Bolt it on
• Steering
• Wheel
• Cut out sheet metal and mount custom shaft housing
  
• Sand down more off wheel for throttle
• Shaft
• Get control arm welded
• Mount to front axle
• Wheels
• Stick 'em on
• Add pimpin' stereo system
• Brakes?
  

It's mostly sliding stuff on and bolting stuff in. The hardest part will be finding somebody to weld that thing on the steering shaft. I expect to finish up everything either today or tomorrow. When my chain and sprockets arrive, I can finally get this thing moving.

Tenth Hour

FINALLY, my parts arrived. The crucial rear axle and steering column came via UPS today, and I couldn't be more excited. Unless I realize that I don't yet have any sprockets or chain. But besides that, I can finally make this thing at least look like it can move. I got some replacement E-clips from a (very) nearby landscaping place that happens to sell and repair lawnmowers. I had to saw off a bit more of the front pipe to give the wheels some clearance. I made some spacers out of copper pipe to fill in the gap. For the steering column to fit in, I'm either going to drill another large hole in the front pipe, or I might use one of the steering arms to keep it in place. I only need one anyway, and they gave me two, which I will need to weld onto the column.

Speaking of steering, the steering wheel I had carefully selected doesn't fit on my steering column. It seems like they should, same number of splines and all, but despite my best efforts, I couldn't get it on. So, I hacked it off. In the little bag o' tricks that came with the steering column, there is a mounting plate. So I'm going to cut apart a little sheet metal to the right shape and custom fit it on there. Shouldn't be too much trouble.

Also, the throttle I have is designed to be mounted on a scooter handlebar, so I've ground a bit of rubber off the wheel to affix it within thumb's reach.

After getting the motor hooked up properly, I'm starting to wonder if I should have included brakes on this monstrosity. I was planning on throwing the motor into reverse for brakes, but since I discovered the motor has no reverse...

Here's my idea for the simplest brake. There's a bar on the back of the kart, a rear bumper if you will. If I attach a piece of wood to it on a pivot, and rest the other end on the tire, I can slow down or stop the tire by pressing the wood against it. I'll draw up a picture.

www.flickr.com

Ninth Hour

I can't believe how much I got done today (yesterday). It all started when I realized I had other stuff to do besides wait for parts to come in. Then I kinda winged it from there.

I cleaned off that piece of wood I had been using as a table and went to it with my trusty circular saw. I cut it to size, and then realized the wheels would need more clearance in the front. I also had to leave room for one (two?) batteries on each side. The result is the most awesome octagon ever seen. I bolted that to the frame with some U brackets, leaving some spacing for the clamps. After mounting the controller to the back, I screwed some blocks and eye hooks to keep the batteries in place.

Tomorrow (today) I expect to get the seat mounted.

Really picking up momentum.

Back in business

The motor is back in action. In fact, it's better than ever. Nothing was wrong with the motor as it turns out. The two batteries I was using were marine batteries, meaning they have short circuit protection. For those who don't know, a short circuit would be just directly connecting the two terminals. This makes sense for a marine battery that could be say, dropped in salty water. However, high-amperage applications like an electric vehicle for example could be misconstrued as a short circuit, which is why the batteries weren't delivering. I stopped down by Wal-mart and picked up two automotive batteries (2 * 12v = 24v) and lo and behold, the thing moves. And it MOVES. Much faster than I've ever seen it go.

I'm back on track. I FINALLY found some gears and sprockets that will fit my purposes. After six weeks of searching and the help of my surprisingly internet-adept father, we've got the right drivetrain on its way here, and I'm going to cut and mount that hunk of plywood onto the frame to hold my stuff down. The motor might be a problem... considering the shaft is 15/32" and the sprocket is 1/2", but I think it will be "good enough." I will most likely end up making my own little collar from copper pipe which just happens to be a little under 1/16" thick.

While I couldn't find the E-clips I needed to get the front wheels mounted and ready to roll, I did notice a nice, keyed, 3/4" shafted gasoline engine at pep boys today. Not only was it tempting, since it would fit perfectly with a wide variety of sprockets, it made the "hybrid" aspect of this project that much more attainable.

No I will not finish this project by the time I have to give a presentation on it, but I will finish it in the following weeks shortly after.

It's thundering like a BEAST outside. No rain, just thunder. I'm surprised we still have power. Peco's been good about no power outages recently. Time to play F.E.A.R. with the lights off :D

Hybrid?

Yeah, in my project proposal I had thrown out the idea of making a hybrid go-kart. It seemed like a simple task on paper, but then again the entire project did.

Turning this into a hybrid would mean finding a 24V DC generator (or other and get a converter) and connecting it directly to a small engine of sorts, like a weed whacker or other lawn tool. Right now though my primary concern is getting the motor and batteries I have working, not adding stuff to them. Since I have a feeling this won't be complete until after May 30th, when I am to present this project, I will try to add hybrid functionality over the summer. I'm more concerned right now about building a go-kart that goes than one that is good for the environment.

Turn for the worse...

This project is looking more and more grim. Stuff isn't coming in, I can't find ANY parts to fit what I need, and now the motor is on the fritz. Buying a new motor is out of the question and I wouldn't know how to mount it, considering the special way this one was built.

So here's the deal... I've got to give a report on this failing project in about a week. I have a strong feeling that this thing will not be finished by then.

I'm very frustrated right now. I couldn't get the motor for a while, then there was some trouble with the fittings, and electronics, which set me back about ten days, and I couldn't order the rear axle parts until I knew what size the wheels were. Then I straight up couldn't FIND a rear axle for the longest time, and since I ordered it some 8 days ago, it still hasn't shipped. And absolutely nobody has any sprockets that will fit my motor and axle.

I need a machine shop of my own. Or just be in college.

And apparently I'm supposed to write 6 more blog posts. It didn't seem hard to do when I started this project, but since I've been able to do absolutely nothing for a week, it's all gotta happen in the next six days, which it entirely ISN'T.

I should have just done something easier, more defined, like an internship. Am I prepared for the adult world? Apparently not.

Front steering

I gallivanted down to my grandparents' house Saturday to get the front steering set up. It seemed a simple task. I needed two holes drilled in a section of pipe. Simple, no? Well, yes it actually was pretty simple, but I could not have done it on my own. To drill a hole in metal, you have to start out small and get progressively bigger. So drilling one hole is more like five.

I got down to my grandpa's house and we went right to work. I had been in his basement a couple times before, but I never got a good look at it before. The place is downright magical. He's got at least two of everything you can imagine. We have one rubber mallet at home, and he's got six, in all different sizes. We made our way over to an old looking Black and Decker drill mounted on a vertical press to get this job done. When I asked him how he got it he told me that he worked as a mechanical engineer for some large companies. I asked, "How did it get from there to here then?" to which he responded "Well, how did that medicine get in your medicine cabinet?" My parents are both doctors, so his point was well taken. I would admit too that when stuff is no longer needed by a company, of if they can be convinced that it isn't needed, it tends to disappear rather quickly.

After much effort, we got the holes drilled. It took a bit of grinding down to get the control arms to fit, but they fit well, angled perfectly. I threw a rod on there for steering that I will connect to the steering column when it arrives... If it arrives... :/

As the deadline for this project nears, I'm becoming more and more impatient with UPS and the stores I've bought stuff from.

www.flickr.com

All about control

I finished the wiring as much as I could without an on/off switch, which doesnt seem that important right now. However, I've been reluctant to fire the thing up, to see if the motor spins. Instead of asking "Why haven't you turned it on yet?" ask, "Did that thing come with good instructions?" "Do you know if it thinks 5k ohms means stop or full throttle?" "Do you feel like paying another $275 to get another one if you break it?" The answer to all three questions is "No." Until I get some more answers, I'm gonna lay off messing with it.

Coming Together

The Magical Mystical GoFast is starting to take shape. The frame is pieced together, the motor is mounted, and the speed control finally came.

Being an old starter motor, the motor had a solenoid bolted on top of it. After I removed it, it left four bolt holes just waiting to be used for something. It would be perfect for mounting something to it. I wanted to mount it on some crossbars going across the width of the frame, that way I could adjust it forward or backward to get the chain tensioned up right. See the picture below for the motor mount.

When I mounted the motor and threw some juice on it, I noticed something peculiar. The motor spins the same direction regardless of which wire is positive and which is negative. Took me a bit to figure out why, but I understand it now. Most motors use large magnets in the motor can for the armature to pull around. This motor however, uses wire coils to generate that electric field, so when you reverse the polarity, you also reverse the magnetic field, thus canceling the two changes out. You can tell in one picture, the motor is mounted one way, and in the next, I've switched it around.

As for the controller, I got around to cutting and crimping the wire to the right lengths and got it all wired up. I had to make some special clampy things to fit on the batteries due to their non-standard standoffs. I had to stop my wiring work when I realized I don't actually have an on/off switch. I'm hoping to find one of those really big ones shaped like a tuning fork mounted on a hinge. Think "Throw the switch Igor!" It's got to be able to deliver up to 250 amps, but not at contact. If anyone has an old electric chair sitting in their basement, shoot me an email. :P

www.flickr.com

Ready for some... Progress?

My clamps arrived Monday, and most of the electronics arrived today. I say most because my package was missing one product... the $275 speed controller. Now I'm not saying it's foul play, but the most expensive item in the group goes missing?

Well anyway. I started work on the frame, which is pretty simple. After seeing the clamps, I'm actually pretty confident in their ability to keep the pipe in place. If not... the clamps are steel, the pipe is steel, and my original plan was to weld it anyway.

Here's a picture of the nearly finished frame. It still needs brackets to hold on the rear axle, and holes drilled in the front for steering. Note: That bar in front is just to line stuff up. The finished product will have a larger wheelbase. The entire frame is also upside-down.



Update: The controller ships from the manufacturer, not EVUsa, the retailer I got it from. No worries.

Taking it slow

Yeah, I haven't updated in a while... What with this fittings situation and ordering the electronics, I've basically entered shipping limbo, as I wait for my stuff to arrive. I've kinda hit a roadblock. I need to figure out how I'm going to transfer the power from the motor to the wheel now. The wheel has a keyed groove in it, which shouldn't be a problem, but the motor shaft doesn't. A sprocket with a setscrew probably wouldn't be strong enough, so I'll either have to take it some place to mill a groove in it, or somehow figure out a way to use the hole drilled in the end to my advantage. The hole was used to keep a starter gear thing from coming off the shaft. My other option is to see if I can use that starter gear thing... it's a bit hard to explain exactly what it is. Anyway, When I finally get the stuff in, it will be nice to make some progress again.