Wednesday, April 25, 2007

Another small problem... Resolved!

Well, I was cutting the pipe for my frame today when I realized something. This picture pretty much sums it up.



My father keeps telling me, "No project goes without problems." Time to start listening. My two contingency plans involve either the Simplified Building Concepts guys to cancel my order, which I've already called them about it, so that I may order the right size clamps, or, buy a different sized pipe and cut the pieces again.

Speaking of cutting the pieces.

Chop saw with metal-cutting blade? No.
Hand powered hack saw? No.
SUPER SAWZALL?! YEAH BABY!

Update: We talked with the guy over at Simplified Building about it and he claims the clamps will fit any pipe below 1.32 inches. My pipe's outer diameter is 1 and 5/16 inches, or 1.3125, so it should be fine.

Monday, April 23, 2007

Framework


Framework
Originally uploaded by zzm634.
For those of you that have been wondering what this thing is gonna look like, I've laid out the frame here in my garage. I have one concern, and that is that the weight of the batteries could be too much for the piece of plywood i'm going to use as a base. If it is a problem, it shouldn't be too problematic. I've measured it out and I'm going to calculate the parts I'm going to need tonight so I can order them online or pick them up tomorrow in store somewhere.

Saturday, April 21, 2007

One man's trash...

Another day of progress it seems. Rocky told us of a place "where lawn mowers come to die." Convenient. I was in the mood for some tires and a steering mechanism, and that's just what I got. I returned with a bunch of tires of varying sizes (the big one goes in the back), some steering... axle thingies, a throttle that could work if it's the right kind, two seats, and most importantly, the steering wheel. The guys let us have the stuff for free, so in return, we bought them some pizza.

Eat up some photos:

www.flickr.com

I really like this whole junkyard deal. I think I shall be doing it more often.

Friday, April 20, 2007

Trial Schematic


schematic
Originally uploaded by zzm634.
I've cooked up a schematic for my wiring. For the ignition switch, I'm not exactly sure if the contactor circuit would work. It draws its power from the battery to complete the circuit, but I wonder if when the battery runs down, will the contactor disconnect? If so, this could be a cool low-voltage shutdown switch. If not, then I will have to use a seperate 12v standby battery. Also, the contactor relies on a magnetic coil; it's basically a solenoid in a box. If the voltage drops slowly, the contactor would disengage slowly, which could cause problems with arcing.

Any suggestions?

Now it's official

Today was officially my last day of classes. I still have some APs to finish, and some reflections to get in, but I look forward to having the time to really get into this project.

Crisis Avoided!

zm634: crisis avoided!
mrb4rkz0r: what crisis
zm634: with my motor
zm634: do you know how an electric motor works?
mrb4rkz0r: no
zm634: care for an explanation?
zm634: it will help my story
mrb4rkz0r: sure
zm634: well, you got this thing in the middle called the armature
zm634: it's basically a cylinder of steel, iron... some magentic material
zm634: magentic
zm634: anyway
zm634: it's cut into sections
mrb4rkz0r: ok
zm634: equal sections
zm634: angularly
zm634: then wire is wrapped around said sections, so that when current goes through them, a magnetic field is created
zm634: then you got magnets (or more coils) around the armature
zm634: and the coils in the armature go up to this thing called a commutator
zm634: the commutator is a very smooth smaller cylinder that is also sectioned off to the same number of sections the armature has
zm634: this is where the coils of wire go
zm634: to get power to these wires, metal blocks called brushes rub against the commutator
zm634: and the way they are angled and sectioned off creates magnetic fields in such a way that the thing rotates
mrb4rkz0r: ah
zm634: i wont get into magnetics, but you get the idea
zm634: anyway, these brushes here are on springs, pressed against the commutator, because they wear down over time
zm634: this motor here though, is really.... REALLY heavy
zm634: so i thought i'd try and remove the whole starter solenoid part
zm634: which weighed a ton
zm634: so i unbolt it, and go to pull it off
zm634: and the armature kinda slides forward a bit and i hear this "chlick, chlick"
zm634: and ima like... crap
zm634: the commutator had slid forward and all the brushes had slid in behind it
mrb4rkz0r: mmhmm
zm634: like, imagine two people pushing two blocks perpendicularly against something in the middle
zm634: then pull that thing out and try and get it back in
mrb4rkz0r: ooh
mrb4rkz0r: bad
zm634: so now... normal motors have 3 sides to the armature and two brushes, one on each side
zm634: so i know i have to pull the brushes apart to slide the thing back in
zm634: and i see these two big holes on the side with a fancy cover thing... right about where the brushes would be
zm634: i unscrew one and, success! i find a brush!
mrb4rkz0r: lo!
zm634: on the other side too! happy day, this will be easy
zm634: i got lucas and maddie to get needle nose pliers and pull the brushes out while i slide the armature in
zm634: remember, brushes on springs
zm634: i try pushing it in... no dice
zm634: lucas tries... still no dice
zm634: i gramble, come up here and read some digg, while trying to figure out how to get this thing back on
zm634: i decide i've gotta take the back plate off that has the brushes in it, and stick the armature in it while they're pulled back
zm634: i get all the screws off, and what do I see?
zm634: EIGHT brushes
mrb4rkz0r: haha
zm634: now if i were some hindu god, this would be easy
zm634: unfortunately, i'm not
zm634: and all these damn things are on springs
zm634: STRONG springs
mrb4rkz0r: so what did you do?
zm634: well... first failed attempt, i tried to wedge the springs open with long nails long enough to slide the thing in,
zm634: then take the nails out and it clamps down
zm634: that didnt work at all
zm634: then i came here and watched those GI joe psas
zm634: then i asked, myself... why not just take the brushes out?
zm634: GENIUS!
zm634: i pulled back the springs... slid the brushes out
mrb4rkz0r: ah ha!
zm634: stuffed the armature in the bearing on the end, pulled the springs back... stick brushes back in!
mrb4rkz0r: yay!
zm634: and that's what i've been doing since I got home [4pm to 9pm]
zm634: :/
zm634: I did get the starter assembly off though
zm634: and tomorrow I get to use my special metal saw blade
zm634: metal-cutting
zm634: saw blade
mrb4rkz0r: cool
zm634: it appears to be just like... sand or something
zm634: but anyway
zm634: my fingers are still black from the grease...
zm634: and i still smell like a steam engine operator
mrb4rkz0r: haha
zm634: it's quite a distinct smell
zm634: i should have just used a steam engine
zm634: it would have looked so cool
mrb4rkz0r: haha

Unfortunately I didn't have the mind to snap some pictures of the MASSIVE armature inside the motor before I got it all together, but it's unlike any I've ever seen. I did manage to get the solenoid garbage off though. Here are some more pics:

www.flickr.com

What I've learned from this? Keep a calm head and don't rush things, or you WILL make a mistake. Also, if something's really hard, you're probably doing it wrong.

Motor and Battery

I got the motor I'm going to use yesterday and I decided to snap a few photos to show you all how big this thing is.

www.flickr.com
Getting this motor was an interesting task, one that has probably changed the way I view life itself. Sounds kinda corny, but it could be true. I had been looking around online for a motor powerful enough to get the job done, and I had only come up with ones in the $500 variety. I then began to consider the scrap yard option, as in, scrounging around for one. I've been watching as much Junkyard wars episodes as I could get my hands on, and I had this glorious picture of mountains of junked vehicles and parts everywhere, being able to run free and look for what I wanted to my hearts desire. I proposed the idea to my father and he said he knows of three junkyards in Morrisville we could check out. Excitement grew.

However, while I was still looking online and planning stuff out, my father had called around and asked if they had anything I could use. I was surprised he did this, and a bit unhappy that I had not done it myself. He told me about this man, "Rocky" who had found a large starter motor that changed its purpose from boat engine, to large truck engine, to airplane turbine engine multiple times before we got it. It seemed every time my father called him to ask if he had it yet, something had come up. After two weeks of calling, he finally got it one day while I was in school. My dad sent me a text message stating "gon pick up motor after work." I became more excited still.

Now though comes the reality. We drove out to what I thought was a scrap heaven, which turned out to be a auto body shop that seemed to be just in some neighborhood. My idea of "Rocky" was also a bit off from the truth. I imagined a perhaps partially crazy guy hoarding over a pile o' junk and saying "whatever, anything's $2!" Instead I got what appeared to be a regular guy!

We spoke with him a bit about my project, and how he couldn't get it to us sooner because his basement had flooded, and then he took me out front to the trunk of a old Cadillac. Inside was not exactly what I would call a motor "worth a thousand dollars new." It was black and somewhat rusty, with a metal-stamped label riveted to the side that said Delco-Remy in less than modern font (see the picture above). He was glad to show me the ins and outs of how the thing worked, what the solenoid did, and he hooked an emergency battery up to it to show me how well it still worked. He seemed to enjoy talking about it, even though I kinda knew what everything was, I let him tell me anyway.

After lugging the 80-pound behemoth to the back of the van, we talked some more. He refused any kind of payment for it, I guess content that he was helping out a student with his project. We talked about his job, how he's still doing it after 43 years. He's got six kids, all of which at one time worked at the auto body shop (if that's what it can be called) and 14 grandchildren. My dad said he was the perfect example of a hard-working American. He's always worked hard and had little more than a house in Levittown, and he's perfectly content with that.

He gave me some good ideas, some sage advice, and then sent us on our way. Talking to him has certainly changed the way I look at society now. I was surprised that he not only went through two weeks of calling around and searching to find this thing for me, but he did it without any reward. Quite a different approach than this cut-throat, buy or be bought world I'm told I'm in. Hopefully I'll meet more people like Rocky, friendly and eager to help.

Welcome

Hey all, I've finally started this blog, because I finally decided on a name for my project.

The GoFast, hurrah for 90's web capitalization.

This is my senior project at Princeton Day School. I somehow got them to let me build an electric go-kart, something I would have loved to do anyway. I'll be posting frequently, keeping you up to date on the problems I encounter, the solutions I find, and the experiences I experience.

I give my thanks to Sir Marcus of Neurotikart for his help and inspiration.

Keep posted