Thinking capacitors and barrels

I don't have any capacitors in my electrical gubbins box. Doing a little light reading, it seems that I could put a capacitor to charge from my 9v battery then discharge through my electro magnets.

Using my key switch, I have two positions. The first can be used to charge the capacitor and the second to release the charge through the magnets.

As I understand capacitors, they remember the voltage put into them and then build up to capacity with power. The 9v battery trickles power out at a low rate. The capacitor can dump it at a high rate. Thinking of it like a dripping tap, dripping into a bucket, the bucket will fill slowly. Emptying the bucket can be done faster. Indeed a bucket of water filled from a tap is my fail proof method of unlocking a blocked toilet!

So, the new idea is to keep on with the 9v battery but to add a capacitor to dump power into the magnets. I have no idea how much power I'll need so I'll have a look in Radio Shack for their biggest electrolytic capacitor. I gather a diode is recommended in order to protect the capacitor so I'll put one, even though the pp3 battery connector is unidirectional.

It could be that I'm barking up the wrong tree with those magnets. They could be junk but it's worth a shot. It's not an urgent task. Worst case scenario, I just say stuff it and wire the magnets via the bus 12v battery and see what happens. Given an adequate fuse, nothing should be that bad!

Meanwhile, I'm going to look for barrels tomorrow. Word has reached me via the grapevine that somebody locally has a pile of 15 gallon barrels for sale. That's tomorrow's task!

Aha or uh-huh or something like that!

On my way from the treadmill back to my bus, I paused as planned at the dollar store. Navigating around obstacles such as empty boxes, transport dollies, uncooperative customers, spilled nastiness on the floors and collapsed shelving, I located the battery rack.

The battery rack didn't have a great selection of batteries so I chose a PP3 9v battery. This was probably a mistake. I'd probably have been better off with 6 D cells though as yet I don't have a holder for 6 D cells.

The original idea for the magnet was to run two in opposition to lift the latch that locks the bus door. As 9v magnets were available, it seemed sensible to use 9v magnets and run them off a separate battery rather than use the bus battery.

As it turns out, the magnets do repel each other but the pp3 battery does not put out enough power to make the magnets work really well. As grippers, the magnets do an excellent job. They're supposed to be grippers. I need them to repel too though.

The next task will be to get 6 D cells and solder them together. That should provide ample power to work the magnets. Another idea would be to charge a capacitor from the 9v battery and use that to activate the magnets. That would involve fiddling around good a week or two with electronics and no guarantee of success. Keeping it simple seems best.

It might turn out that the magnets just won't work and I'll have to make my own. I'm hoping that's not going to be the case but it might have been better to do that from the start.

So, tomorrow's task is to get a pile of D cells. I can always use D cells for my lantern and my shower pump.

Meanwhile, I've got a slight dampness in the cockpit. I'm not sure where its coming from but I'll have to look at the roof seams again. Speaking of which, Eric mentioned roof flashing repair tape and yesterday I saw quite a selection of tapes available to repair roof seams. Some are quite expensive!