DIY floats

[GasSavers_maximilian]

Plastic is what everybody here sells, though I could grab Al at Lowes next time I am near. A lot of people take their plastic gutters in during the winter here. My aluminum one on my shed (have a French drain for the house) pulled right off. The ice laughed at the recommended supports. Adding three times as many this time!

[jmf]

I would think optical would be the easiest. Floats will have to move perfect up and down, to much chance for problems. You could just put a couple optical sensors on the original gauge to detect that float. You would have to clean up the tube so the sensors would "see" through it well. Older copy machines have half a dozen or so in them, so i'm sure you can find them cheap or free.

[GasSavers_maximilian]

I already have a clear tube hooked up to a tee fitting off of the tank, so it would be pretty easy. I have a bunch of phototransistors and LEDs, so I'd just attach them to a piece of plywood, probably, pointing through the tube. If the switches don't work well maybe I'll check it out. There's no rush on this. I knwo tanks get black goop at the bottom after a while, but I think it stays low so wouldn't be an issue.

Neat idea about raiding a copy machine. Around here that's rough, but in general it's a cool thought!

[dkjones96]

You might be surprised. Find a copy machine repair place and ask them if they have junkers you can have. They'll probably gladly give it to you. It was REALLY hard to get the people that replaced our to take the old one. It stayed here for months because they didn't want it in their inventory.

Those copy machines usually have sweet steppers in them too.

I got one of those junkers and it wasn't fancy or anything but I'm sure I got about 6 of those photo interrupters from it. They use them mostly to tell where the paper is. If you get one that has the large loading tray system at the bottom it'll probably be good for about 8-10 of them and about 6-8 stepper motors.

[theholycow]

Originally Posted by dkjones96

You might be surprised. Find a copy machine repair place and ask them if they have junkers you can have.

...then, in addition to the electronics, you'll have a nice pane of glass, some nice sheets of plastic and metal for future fabrication projects, and maybe enough weight in metal to be worth taking to the scrapyard.

[dkjones96]

Yeah, I'd purchased a dozen ULN2003 chips for my CNC projects and it turned out that the machine I got had those same chips for stepper driving. Just my luck!

[GasSavers_maximilian]

Well, the switches I have are a lot stiffer than I thought. I'd need a big float or a long lever to trigger them.

The optical idea is seeming simpler all the time. Great excuse to learn about phototransistors as well. I wonder what the oil's ability to transmit IR is? That's the type I've got.

[dkjones96]

What photo transistors did you get? You can modify your floating dowel rod idea but instead of microswitches you can use optics.

I just came up with another idea. You can't trigger store bought micros with floats, but what about home brew? Put a float on a hinge and when the level drops the far side will lower and disconnect. On the way up the force of the oil makes a connection again. I once made a timer switch for a detonator from a dollar store clock like that. I had an 'interesting' youth.

[GasSavers_maximilian]

Home brew switches normally make me nervous, but this application is
pretty forgiving: very slow response, no need for consistency in terms of force or triggering position, hysteresis is OK, low number of cycles. Definitely worth considering. Shouldn't be very hard and it doesn't need to even be spring loaded.

My phototransistors are Lite-on LTR-4206s.

How many fingers do you have? I was a wimp: I used to just wire a 1/4 watt resistor into a really, really long extension cord and then plug it in from a safe location.

[dkjones96]

I have all my fingers, so far. I have been shocked badly enough to lose the use of my right arm though. My handwriting has been horrible ever since. I never used resistors but I did use model rocket ignitors and if I needed a little extra oomph I always had a box of leftover fireworks sitting around to part-out.