Sunday, August 17, 2008

Mounting the electronics & rear wheel

Each kit is a bit different so expect some cutting and fitting. Also, I found that the order of assembly for my kit was somewhat different than what was specified in the kit. So I've found that it's wise to always be able to undo what has been done in case it needs to be taken apart again. Such was the case with installing some of the electronics. What I've written down so far is the way I would have put the kit together had I known then what I know now!

But first, it's time for more painting. I've taped newspapers all over the BugE so I can now paint the inside of the upper body (don't forget to block the fan so paint doesn't spray up) I'm painting the inside of the cargo area white (so my future cargo is easier to see) and a neutral gray for the rest of the inside. In the photo, it's about half way primed. Originally, I was going to paint the inside with stone paint I had left from another project. However, the paint didn't look too good on a test piece of plastic and I also noticed that it was not good for outside use anyway. So I decided to just stay with the gray. I figure if I don't like it later, I can always go the spray-glue & fabric route. I used spray paint for this step but I would not recommend it. It's very messy, expensive (especially since I went through an expensive disposable respirator) and somewhat dangerous since I was painting in the confined area in front. If I was to do it again, I would just use paint from a can and dab it on with a sponge brush. I decided to leave the front door on since I think the white paint in the middle, leaving red fiberglass trim on the outside may look nice for the inside of the door.

I also painted the bottom of the battery tray black. It's quick and boring so it didn't rate a photo.

Enough painting! Now go back to the frame on the sawhorses and turn it over so it's right side up. The tail for the rear wheel now droops down and the front tires are still off the ground. I recommend mounting the electronics first, then installing the motor and rear wheel after that is done. As you see by this photo, the contactor mounted under the rear bumper-shock hump is a really tight fit. If the motor and tire were installed, I could not even position my arm there or drill the mounting holes! Also, once the contactor is installed, it is very hard to tighten the nuts on top to secure the smaller wires because of the confining space.

So, it's much easier to pre-wire the contactor, put ends on them, then label the wires to show where they will eventually be connected. For reliability, all wire connectors have been soldered rather than crimped on. I don't want to take all this apart again due to a lose connection! Also, in the center, is a diode which has been wrapped in electric tape so it doesn't short against anything else. The lengths of wire are specified in the instruction manual and the circuit diagrams are excellent! Note, the big rectangular brown thing is a resister. I used one which has the same resistance but has a larger power capacity since that was what was available from my supplier. On the lower right of the left photo is the battery cut off switch with a removable red handle that serves as a primitive "key" for the BugE. On the right photo is the contactor once it has been installed, ready to accept two thick cables on the two large terminals.

Seen in the front of the right photo are the two bolts that would have been impossible to drill had a tire been installed. Also, if the motor was installed, it would have been impossible to wedge the contactor into it's mounting space. The contactor was mounted using 2 - 1/4-20 x 1 1/2" bolts & nylock nuts and the left mounting hole was drilled using an angle drill adapter (since the drill I had was too fat). If you're wondering about the Velcro, that's for the motor cover and mud flap (other parts I would install later since they need to be taken off to do these next steps)

Here, you can see the speed controller which is mounted to a piece of white plastic under the front hump of the bumper-shock assembly. Use a jig saw or table saw to cut a board 7"x12" piece of 1/4" plastic or finished plywood. (I used an old plastic cutting board cut to size so I wouldn't need to paint it). Mount the controller to the board using 4 - 1/4-20 x 3/4" bolts with the controller's row of spade connectors facing the rear of the vehicle. On my kit, the space was really tight for the controller so I used a grinder to grind off one side of the hex head bolts so the whole unit would fit inside the frame area.

The board forms two shelves. On the BugE models with the reversing motor, the near side would hold the reversing switch and the far side was supposed to hold two 48V chargers (more on this below). The frame is resting on some seats of some old chair cushions. I used these since I noticed using saw horses with no cushioning was destroying the paint every time the frame was set down on them.

There is another issue that I think is specific only to my kit. I had no tab for attaching the hose clamp for a rear motor mount. I expect this was due to the welder forgetting to weld on the tab. I wasn't sure how critical this was to the design so I decided to construct a bracket and hose clamp arrangement to mimic the function of the missing tab. The hose clamp I used is a 5" to 6 1/2" size attached to a bracket of scrap metal and two bolts. A consequence of this is that the motor cover will now need to pass a bolt (probably using a hole and rubber grommet). However, there is a good side to this. The motor cover, secured in this way, is much less likely to fall off!

Now, it's time to put on the wheel, motor and rear mud flap. The manual covers this rather well so I won't bore you with the details. However, I did take this pretty picture of some parts. The MT-2109 motor from EV parts includes the sprocket, key & motor mount bolts. It fit the motor mount perfectly. The motor isn't too heavy but watch your back anyway. The red box is the drive chain that is included in the Bluesky light & control kit. The other flat bolts were also from the main kit and will be used to securely mount the battery tray to the frame.

In the instructions, the motor cover is supposed to be held on to the swing-arm only by Velcro strips. While Velcro alone may work for a few weeks, eventually, the motor cover will vibrate off. In my case, when I hit a pothole. So, my motor cover now has an additional bolt & nylock nut that passes through the top of the motor cover and the rear wheel swing-arm. Since doing this modification, I've had no problems with the motor cover being lost.

My kit came with the large gear already on the rear wheel. Pictured is the rear wheel assembly. Just like the front wheels, the rear wheels have drum brakes too. The axle is also included. When putting on the wheel, just be careful that the brake slot fits with the tab on the frame. When putting on the wheel, it sometimes wants to slip out until the bolts are tightened down.

Now that the rear wheel is on, you need to connect it to the motor gear. To make the chain the proper size for doing this, it's just like how you would do it on a bicycle. Just use a block of wood and a hammer to force the rear wheel in on the frame. Then put on the chain & mark the link which would give the desired loop length. Grind off one side of that link so the chain is shorter. Then put in the provided master link so you have a loop. Then, use a block of wood and a hammer to force the rear tire out so the chain has some tension on it. I'm not sure how much chain tension is good nor the torque values on any bolts so I've been going on "feel". Providing torque values on critical parts such as the rear bolt would be a nice addition to the kit instructions.

The motor cover and mud flap should be mounted last since they need to be removed to provide access to other parts if mounted earlier. When installing the mud flap and motor cover, I found I had to trim both to fit properly. However, they were both very easy to modify using a Dremil cutting wheel. Then I put on Self adhesive Velcro in various spots to hold these parts to the frame. Later, I resorted to an 8-32 bolt and a bent coat-hanger to hold the plastic piece against the motor wall. This solution is not too elegant, but it is effective.

Since I'm doing the reversing motor option, the supplemental instructions show an image of two chargers stacked on top of each other instead of on either side as would be the case for the forward only motor plan. However, there is a problem with the instructions. I found the units included in the deluxe EVparts BugE kit were much larger than the ones pictured in the manual! So, I'm resorting to using a 48V external charging port instead and the shelf will now be used for mounting a DC-DC converter.

That's all for now.

Wednesday, August 13, 2008

Frame, suspension and steering.

While the cowl paint is drying, other things can be done.

First, the shock is installed on the frame. The default shock strength is set to a reasonable setting straight out of the box. No need to buy the bolts and nuts as they are included. The bolt holes were just a pinch too small so I had to use a rat-tail file to make the holes just a bit bigger. Note, the photo was taken with the old paint job. It was at this stage when I found the first hint that the old paint job might need to be stripped off. When I started adding on other parts, the paint started chipping and it was clear I had to redo the paint job. However, when the new paint was applied, the parts went on the same way.

The rear swing arm assembly was reassembled as it was when it was shipped. Since some bolt threads were slightly damaged when I pounded it out for painting, I had to repair it. A jewelers file was good for doing this. Otherwise, the swing arm assembly went together just as it came apart. I added a pair of 12mm washers to the outside swing arm bolt assembly so the paint job is protected a bit more than it is in this photo. The swing arm and bumper bolts stick out but are harmless to leave in that state.

The frame was then turned upside down. The brass bushings for the steering spindle were gently tapped in with a hammer and then attached to the front of the frame. The tie rods and the stabilizer rod (below the tie rod) were then installed. On steering arm, some 5/16 washers were added as spacers to allow free movement of the tie rods.

Post construction note: I originally had a stabilizer bar. However, the shock mount needed additional clearance. So, I could no longer use the rod. Instead, I created a retrofit that uses sliders instead. To date, this design change has worked well. The refit can either be installed at this time or at a later time in the assembly process. The upgrade can be seen HERE.

Put the front wheels on the steering spindles
The kit wheels and brakes parts are made by Tomas, one of the largest moped manufacturers in the world. The wheels come as a unit which includes a drum brake setup for each wheel and an integrated wheel bearing. The rear wheel also has a custom sprocket attached for the chain drive. Replacement wheels used to be available at However, TOMAS A35 5-spoke mag wheels are still available HERE (both front, back and used ones). Replacement brake pads take an EBC-525 shoe. Another part number that would work would be a H302 which fits a Honda sports bike. The tires are moped tires that measure 2.50" - 16". The first measurement is the height off the rim. The second measurement is the rim diameter. Another acceptable tire is NR21 300-16 UNIV REAR STD from .

When putting on the front wheels, a tire adjustment will be needed. This is because a three wheeled car, using two wheeler parts, will have one wheel tread “backward”. (the “arrow” on the side of the tire will be going the wrong way & tread will be backwards). Although it is possible for a person to change this with hand tools, having it done at a motorcycle shop is much easier since they have a special machine made just for that. However it is done, the tread needs to be reversed, then the tire re-inflated to 35 PSI.

Another issue is that the wheels are secured to a bare axle with a castle nut (and cotter pin). I noticed that the hole for the cotter pin on my kit was rather far down the bolt on the steering spindle. So, the eventual solution is to drill another hole closer for a cotter pin. However, the spacer method using washers is used for now so a wider wheel can be easily tried later. The last photo shows this temporary modification of the wheel hub using washers as spacers. As for play, the tightness of the bolt is 1/6 rotation less than snug. (so wheels freely rotate w/o much wobble)

Once the tires are in place, it's time to adjust the tie rods. The recommendation is to have toe-in of about 1/2" so the tie rods don't bend. (that is, the front of the tires are 1/2" closer than the rear of the tires. After this is done, it will be time to mount the rear wheel and motor.

If you are wondering how long this is all taking, I've itemized it below. However, time estimates for this project will vary dramatically from one individual to another. Three things extend time more for me. First, I'm blogging as I go so everything takes longer since I'm deciding on photos & verbage. Second, I'm keeping track of every part purchased and used plus adding notes as I go. So journaling all that takes time. Third, there are some pauses for decisions. For example, do I install a fan, two fans, 5 fans? How many coats of paint should I use for the frame? What shock mount position should I use? Should I drill out another cotter pin hole (and cut off the excess bolt) or do I use spacers? Do I use the DC-DC converter or an extra 12V battery or both? (and if I use an extra battery, what kind do I use and how do I mount it? All these little decisions and debates take time. If I was to do this again, I'm sure this vehicle would take much less time to assemble.

Time used
Re-assemble frame - 2 hours to assemble and cut off any excess bolt lengths & fix threads.
Installing steering spindles, tie rods & stablizer arm. Then align. - 2 hours.
Taking wheel to motorcycle dealer for retread, research & order extra brake parts - 2 hours
Keeping track of parts & ordering additional items needed later - 1 hour.
Installing fan & painting (previous posting) - 1 1/2 hour
Blogging - 4 hours.

Additional materials not specified in the kit
(8) washers of 1/2" ID for wheel mount modification
(2) 12MM washers for rear swingarm
(1) pair of EBC-525 pads for front wheels for spares - $14.95/pair

More painting & installing a vent fan.

In the plans, there is a step that mounts one or more fans in the cowl. The default placement is a single fan placed in the middle of the cowl. On hot days, the fan might be able to provide some small relief from heat in traffic. On cooler days, this fan, combined with anti-fog and RainX should keep the winshield clear.

To install, note the arrow on the fan that shows direction of air flow. Then, take off the exhaust grate. Then, use the metal grate as a template to mark out holes in the cowl. Use a PENCIL, flexible measuring tape and some geometry to get it 12” from the front & placed in the middle. Then paint the grate black so it doesn't reflect in the winshield and while it's drying, do the other steps below.

Use a DREMEL tool Drill BIT on HIGH to carve out the basic shape & drill holes for the screws. Since this is one of those one-shot moments, go slow. Just follow your pencil marks from the previous step. Try the tool in the middle first to see how the tool works. Then, work your way out. I found the drill bit was good for rough cutting in addition to drilling the fan mounting holes. The DREMEL drum sander worked well to smooth the edges.

Mask with tape and newspapers. Then gently sand, then paint. In addition to the cowling, the area that could be an instrument console has been painted too. Initially, surface mounted insturments will be used. This will allow for easy adjustment as various ergonomic placements are tried.

Since the fan is on the bottom of a curved surface, ¾” long, 9/64 diam. screws (and nuts) are used to secure the fan instead of the recommended sheet metal screws. Pictured here, the image shows the longer screws & nuts on the left that were added so the fan could be installed easier.

Next, the outside of the battery box was painted gloss black. Since it's not very visible, gloss or matte black can be used. As for more finishing, the inside of the body needs to have a finish rather than just the reddish fiberglass color. The finish should look nice, be water resistant and not be too expensive. I'm thinking stone although rubber undercoat has been suggested as well.

Friday, August 1, 2008

Enough hype - how much money would I save?

There has been a lot of hype when it comes to how much an electric vehicle costs. Such false claims make it so people have much higher expectations of an EV than they should. Some cite figures as low as a penny a mile, which may be true if just counting JUST the electricity but that does not cover all the costs.

So, here are the true costs I anticipate having for my EV

The cost of electricity is really quite inexpensive. The often cited figures of $0.01 a mile that electric car owners often cite are probably not that far off. For a full charge, the BugE is rated for around 1.5KWH. My electric cost is around $0.08/KWH, so that's $0.12. To put things into layman's terms, to charge the BugE, the charging unit takes around the same energy it takes to leave a porch light on at night.

What some people forget when citing EV operationg costs is that lead acid batteries are "used up" with every discharge cycle.For example, for the BugE, a full set of Optima D34M-950 batteries should be around $760. They are rated for 300 full cycles (or more partial cycles if I don't discharge them as much). I'm expecting a full discharge could give as much as 20 miles at 30mph under ideal conditions. If I go half the distance before charging, I may not do as much damage, so I may be able to go more miles. If I go faster, wind resistance becomes significant so I can't go as far. So, analysis is rather difficult unless some standard of performance is assumed. So, let's assume a full cycle, 20mi at 30PH. So, assuming 300 cycles, that would be 6000 miles before I would replace my battery pack. If we assume a new battery pack (with shipping and/or taxes) costs $800 and divide that by 300 trips, we get$2.66 per trip. Adding in the cost of electricity for the trip, we get $2.78. So, it would be like I had a car that got 20mpg paying at least $2.78 for petrol. I qualify that figure since hills and irregular speeds would decrease the range per charge by quite a bit.

What this shows is that a BugE might save money if gasoline starts going above $3/gal but it's hardly a revolution in doing so. Plus, I'm giving up quite a bit of performance to get the cost savings. However, if I did a full size conversion, I get more performance but per-mile costs go up too since I'm hauling around more vehicle as I go each mile. So, if I was to do a full size ev-conversion using 4x the batteries, that would mean roughly 4x the cost to go the same number of miles. No wonder we don't see many EV's on the road!

Of course, different packs have different costs. Lithium is more expensive but also has a longer service life with better performance. My personal favorite is the Edison nickle-iron design. Those cells are pricey but they have better performance per lb than lead and boy are they are tough! Some nickle iron batteries used in the railroad industry have been in service for over 30 years! Using those batteries would make the BugE significantly more favorable as a transportation solution. Unfortunately, I am aware of no nickle-iron pack in a size suitable for the BugE.

So, if I'm not saving money by using lead acid batteries, why bother? The repair costs are where I anticipate big cost savings will be. This is because several systems such as exhaust, cooling, climate control, transmission, ignition, airbags and other expensive accessories do not exist (if they don't exist, they are totally reliable). I'm accepting that more little tune ups for the BugE may be needed, especially in the first few weeks of operation. However, the fixes will be rather simple and inexpensive compared to maintaining a petrol car. I am also expecting that the maintenance cycle will be different than on a regular car. For example, I would expect tire lifetime to be similar to motorcycle tires which tend to be replaced every season. Since the BugE extends the season, the tires may need to be replaced twice a year. Although this is more often than automotive tires, the BugE tires are only $20/ea. and of course, I only have three of them. I may also have more wear on the rear tire since that is what propels the vehicle. I'm assuming the wear on the brake pads would be similar to a motorbike, which should probably last around 10,000 miles.

I have been tracking my expenditures rather closely. So far, I've spend $8100 in materials and anticipate spending close to $9500 when I'm done. This includes all materials, batteries, & additional tools I had to purchase for the project (such as the tool chest). I am also including materials that I lost to mistakes (such as the expensive galvanizing paint, stripping & repaint materials). As for trips to the stores, I'm satisfied claiming $5/retail trip. So with 20 trips, that comes to $100. If an online purchase was done, the shipping cost was included. If purchased via retail, sales tax is included. I am NOT counting tools I already had such as screw drivers, pliers, socket set, a 4" grinder & small Dremel set. (I think all tools I've used so far would be safely less than $300 - especially if shopping at places such as Harbor Freight.) If building more than one BugE, I'm sure there are significant savings that could be had by buying materials in bulk and splitting the cost across many units.

There are lots of unknowns in this area. Hopefully, the BugE will be driven in the rain more than a regular motorbike. It also can be driven in the winter on days where there may be no snow, but where salt may be on the roads. So this may lead to more corrosion problems than I would see with a regular motorcycle. The canopy, could become scratched over time with multiple applications of RainX. The controller electronics, although simple, will be in a cold moist environment so they may not hold up too well. The motor in theory should last a long time.