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First, you may want to
visit the Archive Page One, which tells all about
the first two months of this project, the acquisition of the donor car,
the repair of the engine, and all of the groady details up until now.
January
31st. A new page for a new month (February).
I'm working on completing
the installation of the AC generator before I start on the towing tongue
and cut the car down the middle. It seems to be a lot easier to
reach the engine compartment without having to lean over a bunch
of hardware attached to the front of the car, and this generator
is damned heavy, clumsy to handle, and is requiring a lot of
effort to make fit into the engine compartment.
Today, I decided on a mounting bracket
configuration, and began construction on it. I have a lot of
welding and small fabrication to do, but it should be pretty much
done within a day or two. I still need to move the radiator about
¼" towards the driver's side of the car. Doesn't sound like
much, but I am out of room, and running into obstructions. I did
think about taking the radiator to the shop and having it cut down
an inch, but that would be, well, expen$ive!!!
Feb 3rd.
Today was a complete wash-out as far as the weather goes, but
yesterday, I purchased 15' of 2"x3/16" steel box tubing
and a trailer coupler fitting so I can begin construction on the tongue.
Also picked up some fasteners, and traded a full tank of argon gas
that I purchased a couple of years ago to weld aluminum for a tank
of 'Cougar', which is a 25-75% mixture of CO² and argon. Using
this instead of straight CO² will improve the quality of my
welds, and make welding thin steel much easier. While at the
welding supply store, I also got a fresh tank of acetylene for the
gas torch.
Evening yesterday, I converted my drill
press (such a handy tool!) into a light-duty milling
machine to make some needed modifications of an aluminum fan
spacer that I will use to mount the second pulley on the
crankshaft for the generator belt to run in.
Today I mostly just cleaned house and
cleaned the Crown (see elsewhere on the site), which I have been
using as a workshop for the last two months while working on the
pusher. This evening I used the on-line ordering feature at Jameco
Electronics to order a ball bearing servo motor to use to remotely
control the engine throttle on the trailer. Now I won't have to
use a piece of string tied to the injection pump like I was
planning. To finish up the day, poked around on the 'net and
learned more about servo motors and how to control them. It's
soooo simple when you're exceptionally intelligent like I am!!
Feb 8th.
The first meeting of electric and diesel. The much-anticipated snow
storm didn't happen today, and in fact, it didn't even rain until
late afternoon, so I got out and flushed the cooling system on the
pusher so I could put in some anti-freeze and stop fooling around
draining the radiator after each time I ran it. (Oh yes, the
radiator is installed now, I spent yesterday constructing custom
mounts and carving up 5 radiator hoses and reassembling the pieces
to connect the radiator to the engine.)
Since it was required to run the engine up
to operating temperature three times to flush, rinse and mix the
antifreeze compound, I decided to use some of the available power to
charge up the EV using the now fully installed AC generator on the
engine. The results were mixed. The on-board charger on the Rabbit
requires line frequency to be pretty close to 60 Hertz to operate.
When I tried to set the speed of the diesel to give me that output
from the generator, the engine would kind of "avalanche"
past where I wanted it to run, revving too high for the charger to
work. Not sure what that's about, might be normal, or I still might
need an injection pump. I'm considering other options, such as
converting the AC to DC so that the frequency is irrelevant. The
batteries want DC anyway, so why stress the small stuff?
Before going in for the evening, I built a
small electronic circuit to test the servo mechanism that I intend
to use to actuate the throttle. It worked well enough for a test. In
the next few days, I'll create a more sophisticated PWM circuit to
try.
Feb 11th. Now I'm learning robotics. In
order to make the throttle work, I'm designing circuits from
scratch to have the attributes necessary to adapt the RC
model servo mechanism to properly actuate the accelerator lever on
the diesel injection pump. In this image, the custom circuit on
the prototyping board at the middle is sending the servo (bottom
right, with the round white wheel) a pulsed signal corresponding
with a position of approximately 45° from the at-rest position.
The servo is connected to a spring scale, which is indicating
about 4 pounds of thrust, which is about what the diesel injection
pump lever requires to move. The digital meter indicates a servo
current of 0.33 amps, or about 2 watts at 6 volts, not a lot. I
let the servo hold this thrust for about a half an hour to see it
anything got hot, fried, or failed. Looks like this servo can
easily pull 8 pounds, and as much as 10.
At right is the face of the oscilloscope,
showing the pulse waveform, and the frequency counter, which
indicates that the pulses are occurring every 16ms, or at 60 Hz.
To change the position of the servo wheel, the circuit changes the
ratio of on-to-off as shown on the 'scope screen. The original
purpose of the integrated circuit I am using is as a switching
power supply driver, but it makes a dandy pulse width modulator as
well.
Not shown here is the work I did Friday
and Saturday, cutting out the pieces and beginning to weld up the
towing tongue that will be mounted in the front of the remainder
of the car. More on that when the weather improves. Working
outside with cold steel when it's 35° F and drizzling rain isn't
my idea of a pleasant Sunday afternoon.
Feb 13th.
As the Klingons say, "Today is a good day to weld",
or at least better than yesterday. I thought that laying some
beads down on the thick metal of the towing tongue would be a
piece of cake, but when I tried to assemble the pieces, I had
nothing but trouble. Adjusting the wire speed, current, gas flow,
and technique yielded little improvement. All of the welds
penetrated the base metal OK, but the appearance was totally
unacceptable, they looked like an amateur had gotten a hold of a
wire feed and went nuts. I ground down the ugly welds, and today
used my reliable old stick welder to go over the joints to improve
the appearance and fill in the shallow beads. Of course, stick
welding leaves it's own imperfections, like spatter and slag, so
now I have still more grinding and wire brushing to clean things
up a bit.
Valentine's Day. And what better way to say "I love you"
than with a spray gun? In spite of being basically out-of-commission
with some dreaded virus, I pressed on and finished the welding and
grinding, then laid on a coat of red oxide primer-sealer. So now
this part of the project is done, it just needs to be bolted in
place.
I think I figured out why my welds with
the wire feed were so bad a few days back. I'm pretty sure I must
have gotten a contaminated tank of gas. When I switched back to
pure CO², all of the problems disappeared. Wish I'd tried that
before I was doing the last several welds.
Feb 15th.
I am so sick, even my hair hurts. Didn't get very much done, as I
felt like trash. In what few minutes I was able to work, I managed
to disconnect the exhaust system, and pull out all of the fuel
lines in preparation for the big cut. Just before crapping out in
the afternoon, I did some small stuff to prepare the servo to be
attached to the accelerator cable. Uhg. Off to bed....
Feb 18th.
Uh oh, this project
has been discovered by the EV community. Now the heat will be on
to actually finish it and make it work.
The servo is installed, and
connected to the throttle lever. Yesterday, I welded up a custom
mount that bolted in place of the original throttle cable bracket,
and holds the servo at the right height. I also removed the
original cable, pulling it out of it's sheath, and fabricated a
fastener to attach it to the small, flanged pulley that I attached
to the control horn of the servo. The pulley came out of a junked portable
TV set, so that shows you what kind of resources I'm using to come
up with materials for this dingbat project. I'm thinking I'll add
a spring to the throttle lever, pulling the same direction as the
cable going to the servo. Not strong enough to cause the throttle
to be held open, but enough to assist the servo in pulling the
lever. After all, the spring on the injection pump is sized to be
connected to an accelerator pedal that someone's foot is on. It's
easy to forget how ergonomically designed a lot of our every day
systems are made until you begin to remove them from their
intended use.
Tomorrow, I'll begin the quest to gather
parts for some kind of device to actuate the clutch. I only need
to move the lever on the transmission 1-1/2", but the maximum
thrust is 80 pounds, so It's got to be something strong. I'm
inclined to use the windshield wiper motor and gearbox for power,
perhaps with a lead screw to take up the lever. I'll look for
garage door openers at the salvage building materials yard, they
should prove to have some interesting mechanical parts inside,
limit switches, lead screws, gear, chain, and belt speed reduction
stuff, etc. Maybe I can get the whole pusher to work off of a
'clicker', so I don't have to run wires!!
Hey! What kind of a Pusher update is this??? Feb 22nd.
Part of the reason for little progress on the trailer is that most
every spare minute I've had for the last four days was spent
either trying to get caught up with work for clients, or completing
the installation of this Tachyon.net satellite earth station which
gives me wireless 2Mb/sec download speed. Here, the L-band antenna
is set up on a temporary stand behind the Crown as a test to see
if my site can receive the satellite signal, prior to mounting the
hardware permanently. Now I can download files from the net at
amazingly fast speeds, and even listen to web radio without interruptions
in the audio stream. I probably have the world's only Housetruck
satellite uplink in existence!
Progress on the Pusher will resume soon. My
trip to the salvage yard was delayed until Tuesday, due to Abe and
George's birthdays. Once there, I looked over about 10 cast-off
garage door openers, looking for useable parts. The openers were
of two types, chain drive, and lead screw drives. The chain drive
units might have yielded some useable hardware, but they were
pretty rudimentary, with large v-belt pulleys, or proprietary
worm-drive transmissions coupled to hefty synchronous AC motors.
The screw type were all direct-drive, with specialized sealed
motors. None of them looked like something I could hack into
something more useful.
I decided that I could probably do better
with something else, and on the way out, happened to notice an old
scissors-type auto jack laying on a shelf. It had a lead screw
with matching nut, a thrust bearing, and only cost $2. In the next
day or two, I'll see what kind of mischief I can get into with a
grinder and saw to make this work as a clutch driver.
You
know the old saying, "Half a Rabbit is better than
one".... Feb 25th. I didn't really set
out this morning to do the cutting thing, but about 4:30PM, it was
obvious that the time had come. Spent some of the morning
installing the limit switches on the clutch throwout mechanism,
then installed the towing tongue after lunch. Some disappointment
there, I thought that I had accounted for the angle of the car and
tongue, but apparently not, as the tongue is about 3° too high in
the front. This is visible in the image above. Once again, there
is no substitute for working on a level concrete surface. One day
I'll have a nice drive-in shop so I can be warm too! Anyway, this
problem can be fixed, I just have to block up the trailer (I can
call it that now), remove the tongue, radiator, alternator, and AC
generator to give me some elbow room, then make the mounting holes
in the frame elliptical using a rotary file and drill motor. As I
say, disappointing, because if I had been able to measure this
before building the tongue, I could have simply offset the
mounting holes in the tongue when I drilled them. Ach, live and
learn.
For the record, and in case anybody
cares, it took 20 minutes to cut the car in two, including some
time fiddling with the saw after the blade came off. I knew it couldn't
be too hard, after all, I cut a 40' bus in two the long way! That was
difficult!
For now, the rear of the trailer is
longer than it will be when finished. I wanted to have some fudge
factor when I begin gluing the back end of the car onto the
shortened front.
Feb 26th. I guess that the big news of the day is that the hard disk in my computer crashed after breakfast. I've spent a couple of hours recovering data not contained on the latest backup CD-ROM, but it looks like I'm going to have some important stuff that won't be recoverable. I'm updating here using my old 486/33 laptop with a monochrome display, hand editing the page in Notepad+, so don't look for any fancy stuff until I get a new drive and have all of my programs loaded and ready to go.
I did work on the car today, pulling it out into the driveway and doing some alignment,
using some 2 x 4's, a straight edge and tape measure, before locking the steering rack into a
straight-ahead position. Also removed the heater assembly, pedals, steering
column and some superfluous brackets from the under-dash area.
March3rd.
It's been an intensive week. Aside from purchasing and installing
a new 30 Gb hard drive, and then reloading all of my programs, retrieving
files and restoring from back up CD-ROM disks, I also managed to
work on the pusher some as well. Now that I have Front Page 2000,
Phototshop 5.5, and the drivers for the memory card reader of my
digital camera installed and working, I can go back and add some
images to the week's work.
This
was the scene on Wednesday the 28th. After
spending the previous afternoon installing the original muffler in
the space provided by the 'hump' between the seats and running the
short exhaust pipe out the center of the floor pan, I was able to
start the engine for the first time in a while. This explains the
fuel container on the floor section. The project in the afternoon
was to install the salvaged towing hitch to the rear of the EV,
which was a fairly simple no-brainer, drill some homes and insert
the 7/16" bolts, tighten to almost breaking. Now the problem
with the towing tongue is fairly obvious, the tail of the pusher
is way in the air compared to the EV's angle. The remnants of the
back of the car look like some ramshackle bum's shelter, covered
with tarps and plastic. Can't wait to saw it into manageable
pieces, cull out the useable parts, and haul it off to be recycled!
Today was a fairly low-level Saturday.
Went out to check out a new job installing wiring at a tropical
fish store, ate lunch, took a nap (yawn), and worked a little more
on
the controller for the trailer, at least the prototype that I'll
use to test it with. As I build the electrics, I expand the
project with ideas and enhancements, and have to keep in mind that
the complexity of the controller changes when there is an automatic
transmission in the final (?) product. For now, the controller
will supply ignition (injection pump fuel solenoid), monitor
alternator and oil pressure idiot lights, and control the clutch
in/out. Future enhancements will include starter, fuel gauge,
water temperature gauge, glow plug control and maybe radiator fan manual switch. Important safety
features including throttle defeat, deadman interlock, breakaway
kill, and more will be needed in the final controller.
No promises, but I hope to have
everything ready for a road test by next weekend. I have the
controller to finish, installing the PWM circuit for the throttle
servo, stop, tail and turn lights to install, and a head unit that
installs in the EV, so I can control the throttle and clutch from
the driver's seat. Sunday morning should be a nice, quiet time to
have some space to myself on the highway, so that's what I'm
shooting for. We'll see what the next week will bring.
First the flu, then a hard drive crash, what's next, an earthquake?
March
7th. Question: "Say, isn't that
a Skil® Xtra-tool hammer-chisel-drill in
your engine compartment?" Answer: "Oh you
recognized it..."
Once I had the lead screw and bearing
installed on the clutch arm, the 13/16" hex nut on the end
was a convenient way of running the screw in and out. I finally
decided that a drill motor would be the easiest power source to
adapt to working it on the finished trailer. Since I had this
drill motor under the workbench, awaiting a new variable speed
trigger (waiting for the last 12 years, it seems), I decided to
just use it in the car, mounting it on an aluminum bracket, and
coupling it to the lead screw via a spare spark plug socket from
the tool box. Using this motor means that I will need 110 volts AC
on the trailer to operate the clutch. Since I have a few spare
DC-to-AC inverters laying around, this isn't going to prove to be
much of a problem.
It was one of those
two-steps-forward-one-step-back,
two-steps-forward-three-steps-back type of days. Trying to run the
drill motor from the controller didn't work, and I ended up having
to replace two defective relays in the controller. These things
happen when you build projects out of junk box parts. Then, as I
was demonstrating the drill motor clutch actuator to a visitor,
the clutch arm traveled a bit past where it should have stopped,
and broke the lever arm off of one of the limit switches that
senses where the clutch arm position is. This resulted in a complete
redesigning of the limit switch assembly, a project for
construction tomorrow...
Almost
another week of work on the trailer, but a week of no updates.
March 12th. No I
didn't get the pusher out on the road last weekend. After
repairing the clutch limit switches, I needed to insert some speed
control in the release motion of the drill motor, so I shredded a
lamp dimmer and inserted it into the controller. After that, I
tried the system on a 300 watt inverter that I had lying about.
Worked fine on the "disengage" cycle (full drill motor
power), but the inverter didn't sense a load through the dimmer
module for the "engage" cycle, so I had to insert a
time-delay relay into the circuit to give the motor full power for
about ½ second when the "engage" command is given.
After the time-delay relay releases, the motor goes to lower speed.
so as to not over-travel at the end of the clutch arm's limit.
Whew, one less problem, or one more problem I wouldn't have if I
had an automatic transmission.
Yesterday, I began construction on the control head that will
mount in the EV so I can ride herd on the controller's actions
back in the trailer. Worked out a few bugs, such as the ignition
being back-fed through the alternator warning lamp, resulting in
no way to shut down the engine once it was started.
The three colored lamps are: green: glow
plug activity, yellow: alternator warning lamp, red: oil pressure
warning lamp. The red lamp will also have a second function, which
is to flash when the throttle servo circuit is in "fault
mode", which occurs when the EV's brake lights come on, or
the trailer's clutch is disengaged without the servo being
returned to "idle" beforehand. Just a little safety
interlock to prevent accidents and engine overspeed.
The controller itself is gaining in
complexity with the additional circuitry required to support the
requirements and features I'm building into the system.
Just a
quick little update, Mar 14th. An inside
view of the controller head, with the PWM circuit installed. Only
about an afternoon's worth of stuff stands between me and a road
test now. I need to make an extension cable for the controller
head, so I can operate it from inside the EV, there's still a
short cable from the controller to the servo to be made, and I have to get
some tail/stop/turn lights on the trailer so it will be highway
legal.
Unfortunately, I have a lot of work to do
for clients, so I'm spending more time out working than I care
for. This weekend is supposed to be rainy, so the fun and danger
might get delayed for another week.
This
is likely to be the last update to this page before it becomes an
archive page.
March 22nd.
Everything is ready for the test drive. I completed the control
head and extension cable, installed trailer lights, hooked up the
inverter, and even used some leftover aluminum from the ceiling of
the bus to make a teardrop enclosure to conceal the battery and
fuel container. This cover will be replaced by parts of the
original sheet metal from the donor car, but for now, it was quick
and easy to smack this in place using a couple of sheet metal
screws.
I did tow the pusher out on the road
today as a test. No power, the engine was off and in neutral, but
I wanted to see what the general response of the front clip was to
being hauled around. Got it up to 40 MPH on some smooth pavement,
and basically couldn't tell it was back there once I was at speed.
Of course, the car was a little less peppy (well, I guess it would
have to be "peppy" in the first place to be less so) and
I used about 20% more power from the batteries than I would have
without the trailer along for the ride. No matter on that, the
point is to use the diesel for power, it's not like I'm going to
tow it all around town each and every time I go out on an errand.
That's the point of building it into a trailer, it can be
disconnected and left at home when not needed.
The fuel container is topped up with
diesel salvaged from the tank in the car, all of the electrical
connections are done, and now I just have to hope for a sunny
weekend morning so I can get out on the road and try it out. More
about that when the saga continues.
Continue to Archive
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