Tuesday, May 31, 2011

Steering

So since the existing steering stem was a bit shorter than I wanted...

I had to make my own!  That started with cutting a piece of 7/8" tube stock to the length I want and cutting the end at an angle to create a wedge.  I then used a typical wedge piece on the new extended stem (which took some work to get the right angle) - see photos below:



Then I needed to extend the rod bolt that connects to the wedge along with adding a new bar stem and bars (which I obtained from the Bicycle Kitchen - thanks to them for what they do, it's an amazing place).  I did this by welding a piece of rod in the middle of the ends of the original rod bolt.  Eventually I got the wedge to work and the bar stem to clamp on the new tube stock.

Everything works great! Now I can't wait to put on my fancy grips!  ...waiting till I'm done so I don't get them dirty.  



Thursday, April 28, 2011

Body Update

Subtle changes make all the difference.


Now you can probably gather that this change has made the pedals stick out past the front of the body and that might look a bit odd...but I think I have a solution.  We'll have to wait and see what it looks like when I start adding the finishing touches to the body.

Tuesday, April 26, 2011

Chop, Cut, Rebuild


The body has been built to match the proportions I originally intended from my scale model and now that it is done, I've come to one big conclusion about it...it's all WRONG!  Seeing it in person, it's just too damn big.  My drawing showed a 4' wide, 7' long, 5' tall body and it looked good on paper, but there were a few determining factors that affected the actual positioning of the body on the frame: the pedals and the distance from the driver's head to the front "windshield".  To avoid the cliche, "homeboy driving on the freeway" look, the driver needed to be in an upright riding position and the pedals as close to the driver as possible.  Despite thinking I had the seating and pedal positions all figured out, once the body was made and mocked up on the frame, it just didn't look right.  The front portion of the truck overhung the front wheels substantially more than I anticipated, which in turn pushed the windshield farther further than I wanted.  If I were to push the windshield back in the position I wanted, I would have ended up with a really long front end; which, if you look at the typical "roach coach", doesn't exist.  The front end needs to be smushed up close to the windshield like a pug stuck in a cubby.  Therefore, drastic measures were taken!  The top is being chopped 6" and the front end is being brought back 10"!  The driver's seating position is going to lowered, as well as the handlebars, but the pedals are being left in place.  Now, I'll leave you to your own imagination as to how it will look once the body is all modified and what interesting features may now exist, but all I'm gonna say is that it's going to look a LOT better!
Here you can see the distance from the front wheels to the front end to cover the pedals.

And the distance from the windshield to the handlebars.  =\

Tuesday, April 19, 2011

Selecting Batteries

Being a Mechanical Engineer, I've always been intimidated by electrical design work, but I've finally worked up the courage to take on the flowing charges and do some calculations!

As it turns out, determining our battery size is fairly simple. When we’re looking at batteries online, there is a lot of superfluous information that we don’t need to concern ourselves with. The 2 things we DO need to know about are the Voltage and the storage capacity (in Amp/hour or Ah).

Now, let’s assume our vehicle uses 22.35 Wh of electricity when driving at 15 mph. We’re using this as an estimated value only for our baseline calculation (data extrapolated from cyclone-usa.com test results for the same 500W motor).

As a base point, let's assume we want to travel 30 miles at 15 mph; therefore, we are going to consume 670.50 Wh of electricity during that trip.

Now to figure out how many Wh are in a battery multiply the voltage by the amp hour (ex: 12V x 75 ah = 900 Wh) The battery I'm looking at is HERE.

Seeing as that the motor we’re using is a 24V motor, we will need TWO 12V batteries to make a 24V system and our calculations are revised liked this: 24V x 37.5 ah = 900 Wh. (notice the Wh doesn't change when converting to a 24V system. This applies to 36V, 48V, etc. systems as well.)

Looking at these figures, it appears that we can get away with using just (2) 12V batteries and we will exceed our range/speed requirements; however, because we’re using sealed lead-acid batteries, we need to take into consideration that you can’t take lead-acid batteries below 50% capacity without damaging/degrading them and lowering the battery life substantially. Therefore, in order to meet the criteria set (minimum 1340 Wh total), we need (4) 12V batteries. At $158 a pop, that’s $632...

Now, I think 30 miles is probably a little excessive and since I'm planning on riding this bad boy at low speeds and on flat ground, I can probably get away with (2) 12V batteries; which if I back calculate, I'll probably get a little more than half the distance (15miles) or half the speed (7.5mph)...I think I'll be okay with that. Whew, that's enough electrical for me for one week. =P

Wednesday, April 6, 2011

ROLLIN'!

FINALLY!  Except for a little bit of truing, the wheels are done!  This has been the most time consuming part so far and I can't possibly see anything else taking sooo long.  The concept from these wheels came from the Team Save Ferris Red Bull Soapbox car.  They had a similar style car (thru axles) and I really liked the way theirs turned out.  
I started with the hubs: the 2 existing hubs from the original tricycle and the 2 new 20mm Bitex thru-axle hubs.  Then came the rims: 20"dia by 4" wide rims meant for those OCC Stingray chopper bikes.  Associated tubes and tires included.
Finally was the spokes:  I used a combination of 186mm and 176mm spokes to get the pattern I liked.  I used a cross hub pattern with supports on the outside.
Here's a good before and after:


 Showing the spoke pattern:


and completed:


Looks like I might be riding this thing around at CicLAvia this weekend...keep an eye out for me.

Monday, March 21, 2011

Electric Motor

Since the weight of this puppy is probably gonna be pushing 200+ lbs I figured an electric motor would be quite handy when trying to ascend ANY sort of incline.  To keep things simple, I opted for an electric motor kit meant for a bicycle and adapted it for my rig.  I went with a kit from cyclone-usa.com which included a 500W motor w with controller, gearbox and 14T Freewheel Sprocket; mounting brackets and bolts; a 44 tooth freewheeling chainwheel and crank arms (see previous post for installation); brakes with motor cutoffs; and a battery connection harness.  



I mounted the motor as close to the rear drive as possible to minimize the slack between the two.  With the makeshift brackets, we'll see how well she holds up.

Monday, March 7, 2011

Bottom Brack Freewheel

While I wait for wheels to be finished...I've started working on the electric motor setup.  This means I need a freewheel on the bottom bracket if I want to run the electric motor without pedaling.  Also, since this started life as a "beach cruiser" type bike, it's got a 1-piece crankset...which is pretty tough to work with if you want to do any sort of modification.
Here's what it looks like:
Now, in order to run a threaded bottom bracket, I needed to buy a cruiser to threaded conversion kit; and to install it, I needed to remove the old cranks, and bust out the old cups.  
Now that these are removed (may require some grinding if tack welded in place; mine were not) as well as any excess paint or crud; I can install the conversion kit.  Remember to line up the screws before pounding this bad boy into place!  Dun-did that before...
Once the conversion kit is in place, you're all set up to run threaded cranks!  Freewheeled bottom bracket FTW!  This freewheel crankset came in the electric motor kit I purchased from cyclone-usa.com

We'll be rolling soon!

Sunday, February 27, 2011

Steering and More

Now that the overall frame is done, it's time to start building onto the frame.  First up are the front steering arms.  These are the steering arms we made to accept the 20mm hubs. 
Originally, I had intended to do the steering tie rod in front of the axle; however, the head tube was in the way.  Flipping the steering arms allowed me to locate the tie rod behind the front axle which worked out better because it cleared up the space in front of the axle for foot and leg clearance for pedaling. 
 
Here's some nice welding pictures.

 We're on the fast track now!  More updates soon!  The wheels have been delays, but the electric motor is here.  I need to build a bracket for it, route the chain, add idler pulleys, mount and route the controller, build a seat frame, find a seat, convert the bottom bracket to a threaded, and build a BODY!  A lot of work to do. 

The Frame is Done

With the completion of the steering arm joints, the frame is done.  Now time to get to business. 

Thursday, February 10, 2011

Update

The long anticipated 20" x 4" rims have arrived!  Having a full rolling chassis is quickly approaching.  Tomorrow I will be lacing up the 2 bitex 20mm hubs and the 2 rear wheels to new rims.  Luckily everything is 36 hole so this shouldn't be too difficult.  I think the only issue we might have is determining the correct spoke length for the 2 different hubs.  I will have more photos to add after this weekend!  For now, here's a picture of the head tube welded onto the front frame.  

Friday, January 28, 2011

Frame work

The frame is coming along nicely!  The main steel is all welded up, the rear axle has been extended, the front axle is in place, and the old drive piece is in place.  Now that I have the hubs and axles, I can wrap up the front steering system.  I have a lead on some rims...just gotta place the order and then figure out how I'm going to lace everything up! 


 

Goodies

A nice shoebox from Taiwan arrived the other day with some goodies in it: 20mm hubs and a disk brake set!


 

Tuesday, January 11, 2011

Modeling

The hubs and brakes are ordered, the frame building will start next week, the tires are here; WE'RE MOVING ALONG NICELY!  For now, here are some elevations to keep you interested.  A full 3D model is on it's way!  ;P

Tuesday, January 4, 2011

Frame Design


Now that I decided on the overall dimensions, I've been able to finalize the design of the frame. After building my scale models, I really go the picture that the first design was going to look pretty anorexic. So maybe, this will be a 2-seat truck! Guess I better start looking for an assistant.

Proportionality: Update


So I've made a new model that is more proportionally correct...and I like it a lot better. Looks like I'll be making some modifications to that rear end after all!

Proportionality

I've been having some issues determining the overall dimensions of this truck. I need to figure it out so I know how long to make the new front axle and new frame rails. First off, there's the height. I originally wanted to build this thing similar to a recumbent with an reclined riding position; however, after some sketching and dimensioning, realized that this would position the drivers head really far back from the "front windshield" or it would make the front end un-proportionally long. I want this thing to distinguishably look like a food truck. I therefore had to raise the seating position, which increased the overall height. I was originally shooting for a 4ft overall height, but am now looking at 5ft. This gives me about a 1:2 build scale.

From scaling trucks in pictures, it appears that the length of a typical truck is roughly 1.5x the height. In order to keep the right proportional look (maybe with a little cartoon squish), my truck should be about 7ft long. No problem.

Now, the width of the existing trike rear-end is roughly 24" and to minimize the amount of modifications to this, I'd like to keep it that way. This puts a kink in keeping thing proportional. Typically, these catering trucks are about 8ft wide which would mean that my truck would need to be 4ft wide... To get a physical idea of how this anorexic truck would look, I built a cardboard scale model. I've gotta think about this one for a bit...

Throwing it out there: What do you guys think?

Monday, January 3, 2011

Parts Cleanup


So now that I've got the trike all chopped up, I needed to clean up some of the parts I'm going to be re-using. The head tube is going to be relocated to the front axle and will be the center point in the Pitman Arm steering system. I have been spending a lot of time trying to source parts such as 4.5" wide/20"dia rims, 20mm hubs, disk brakes, and a electric hub motor.

20mm hubs are semi-common on downhill mountain bikes; however, finding 2 spare front wheel assemblies is proving to be quite difficult. I've found a source for new 20mm hubs with a 6 bolt disk setup, so I'm going to give that a try (http://www.bitexhubs.com/htm/hub-b-DH20M.htm). Now, I've gotta find my rims and get them all laced up! I've never laced a rim before so this might be interesting. The old go-to guide for anything bicycle related, Sheldon Brown's website, has a great page dedicated to wheel building (http://sheldonbrown.com/wheelbuild.html) that I hope will make this an easy process.