Ben Nelson's Electro-Metro Build thread

[johnmyster]

I think the joystick should be saved for the lazer death ray you plan to mount to the roof. Or perhaps use it to control the lambo-gullwing doors.

Seems like in some of the electro conversion threads make too big of a deal out of making a pot box. I'd run a bicycle cable to the pedal and anchor the housing on one side of a c-shaped piece of aluminum flatbar. Put the pot in the middle of the flatbar, and put a thread bobbin on the spool and cut a small groove in it. Run the cable to the other side of the bar, but use a spring over there instead. Bam, spring return potbox. Simply adjust the attachment point of the bicycle cable to the pedal in order to adjust the stroke.

Materials - 12" of flatbar, trimpot, thread spool, old bike brake cable (I'm a cyclist, have plenty of good ones) and a spring. Under the hood, a piece of wire, all done.

Those microswitches are used to throw the contactors on the forklift. Forward and reverse polarity, plus perhaps a full-throttle contactor that bypasses the motor controller.

[johnmyster]

Originally Posted by celblazer

I resemble that remark. My 65 Mustang is manual 4 wheel drum brakes and heavy as hell. Power and disc were options. It's even a single master cylinder. Can we say instant death if any wheel cylinder leaks?

AND drum brakes have smaller wheel cylinders than discs have caliper pistons - although they tend to self-actuate to some degree. A drum/drum master cylinder should build good pressure for Ben, even if it was intended to be used with a booster and he intends to use it without.

What am I saying? Drum wheel cylinders tended to be smaller than disc caliper pistons. Thus, they'd need more pressure. Thus, their master cylinder would have been smaller too to make the additional pressure.

Ben, wanna put drums on the front of your car? (J/K)

[bennelson]

Well, I already had a forklift potbox, and I don't have a roof-mounted death-ray (yet), so I figured I'd use it. Kinda cool too how it's already built together with the switches for the contactors.

I was talking with a guy who is doing a 288V pickup truck conversion. He was seriously considering setting all four wheels to drum brakes. I guess disc brakes always have a tiny bit of drag, and drums don't. There was some other advantage to drums as well, I think it had to do with a way of using them without power braking.

[MPaulHolmes]

As far as drum brakes and drag goes, according to Expert Village on youtube you are supposed to set it so the brake shoes drag against the drum just enough so that you get one full revolution when spinning it as hard as you can. I have mine set like that right now, but it might be better to loosen them up just a hair, so that there is less rolling resistance. But I think Expert village would say that that is very naughty.

[johnmyster]

Even if you set your drums looser, they should eventually self adjust back to the right setting. That's why the truly dangerous ecomodders take out the adjustment arm, so that they can manually adjust them to an optimally-loose setting. Even if you set them too tight, they'll loosen as the pads wear. Then when they wear to the point they're too loose, bam, they self adjust to be tighter again and follow the wear.

Problem is that I enjoy having a well adjusted parking brake.

[bennelson]

I fixed the dent on the back drivers' side of the car. Yep, just pushed it out with my hand.

YouTube - Geo Metro Dent Repair - Push on it!

I originally tried using a suction cup to pull the dent, but it was exactly the wrong size and shape for that to work.

I will have an extended video on this later.

Edit:
Here is the full-length version.

http://www.youtube.com/watch?v=S6QwikUfHVY

[toyobug]

ok Ben, whats the latest on your brake issue? I'm addicted to this thread, so I need my "fix" LOL!!

[bennelson]

The latest is that I have no freakin' clue as to how to work on brakes.

I think in the end, I may go with a 12V vacuum pump designed for car or similar use. As soon as I can find a good/cheap one.

The brakes actually work fine for 25 mph or less, making sure you have a little stopping distance. I would like the car to go a little faster and stop a little easier than that.

I think the next thing I really have to do on the brakes is make the front driver-side brake work right. It is really dragging. I may just "PB Blaster"-it and then start looking to see how it works.

Time to break out the repair manual again.

[metroschultz]

Check the caliper slides.
They may be "stuck".
You will need to remove the assembly and clean the rust from the bore.
Then lubricate everything with "Disc Brake Caliper Slide Grease" and reassemble.

As for the brake issue;
I like the Honda Master Cylinder route.
It is quick (you just have to goto the boneyard and get one with a small bore)
requires no booster
simple bolt in application.

Another thought.
look under your dashboard and see where the rod from your M.C. bolts up (actually it will use a clevis pin and retainer)
Can you move that pivot closer to the fulcrum of the brake pedal?
You may have to remove the brake pedal to drill a new hole.
The closer to the fulcrum you make the pivot for the MC rod, the easier it is to push the brake pedal.
IIRC most power brake systems use a 2.5/1 ratio whereas most non-power systems use a 5/1 ratio.
the ratio is a product of distance from fulcrum to point.
I.E. fulcrum to MC pivot = 1
fulcrum to pedal = 5
if you currently have 2.5/1 and you move the pivot closer to the fulcrum you change the ratio and make the brakes push easier.
Most MCs have a ball socket in the front so moving the pivot is not going to jam or bind (unless you get waayay up there).

some random stuff
S.

[bennelson]

Looks like it wasn't the sliders.



I pulled the caliper off the disc. Then took the pads out. With the parts apart, the sliders themselves seemed to work fine.



When I pushed on the brake pedal, the pressure would wiggle the whole caliper unit hanging on the wire from the suspension, but the piston itself didn't move at all.

I pushed a little harder and pumped the brakes. All the sudden, the brake pedal went down much further, and the piston moved quite a bit.

It came almost all the way out. I pulled it the rest of the way and could see there was surface rust on it. Probably why it wasn't moving. Can I grind off that surface rust real careful and re-use the piston, or do I buy a new one?



It also looks like the piston dust boot is torn and there is some corrosion inside the caliper bore as well.

I think I am going off to the auto parts store to see what they have there, how much it costs, etc.

Any suggestions people? Please let me know! Thanks.