# My own little world

Discussion in 'Track Planning' started by Pitchwife, Oct 2, 2003.

1. ### screwysquirrelMember

Lightning

Why not just get one of those Lightning globes and put it upside down somewhere?

the ones that make more lightning when you touch them

it should generate the random lightning you want without frying everything
2. ### PitchwifeDreamer

Hi SS, thanks for the input. The problem is that I am attempting to make this a prototypical world and while you are correct about producing safe lightning, I haven't seen very many purple lightning globes floating in the sky.
Ray, I have been giving a lot of thought about your magnetic base idea for the sidewalks. Putting two belts with magnets under the sidewalk and metalic bases on the pedestrians just might make something like that work. Any thoughts?

3. ### Ray MarinaccioActive Member

Yea, that's it.
I did a little experimenting with a peice of 1/4" square tin and a refrigerator magnet through a peice of cardboard. I found you couldn't control the way the tin was facing, it spun in circles as it moved forward. After a bit of experimenting I found if you use a rectangular peice of tin 3/16" x 1/4" and have both poles of the magnet facing upward you can control the way the person will be facing by turning the magnet. This way the people will always face forward as they move along. You could even have some sort of trip lever to turn the magnet to make a few of them turn to look at something.
I think with a little experimenting the electro-magnet to pull them off the belt will work. I wonder if you can use that idea to make the people move to a different belt, say to go into a store or to cross the street. You would need to have those curbs with the handycap wheelchair ramps. I'm not sure how well they would go across the slotcar track. You may need a stronger magnet for that.
Another way would be to make some sort of linear stepper motor under the sidewalk. This would probably a lot more complicated to build and might be to jerky of motion. Any one have experience with stepper motors?
4. ### PitchwifeDreamer

Actually Ray, I had thought about using a rotating disc with magnets mounted to it on corners to transfer people from one belt to another. Then you would have the belts with the magnets mounted on it only run the length of the block and then roll back under, somewhat like an escalator. With the rotating discs on each corner the people would be transfered from one belt to another.

The problems that I see with them crossing the street are having a magnet strong enough to effect them through the thickness of the track, which would be thicker than the cardboard sidewalks. Also having some sort of insulation under the base so that it doesn't short out the slot track. The right lane wouldn't be a problem as it would be shut down to prevent cars from entering the intersection, but the left lane would remain live to ensure that any cars in the intersection had exited it before the light changed.

I hadn't really thought of tin, as I wasn't sure it was ferrous enough for magnets to effect it. With the tin painted the same color as the sidewalks it wouldn't be so obvious as to how they were moving. I think that a steady speed motor would work better than a stepper. Wouldn't that make their movements jerky?

I bought a bunch of small rare earth magnets that are very small but very powerful. They would attach to a belt, or even be encased inside it, and be great for the job. I had originally bought them to mount in the cars because the reed switches that I had bought weren't sensitive enough for the car magnets to activate. But then I found that one of the tiny magnets placed under the track moved when a car went over it, so all I have to do is affix it to a switch contact and the sensor problem will be solved.
If this works as well as I think it will, it will be a sight to see. Trains going by, cars zipping down the highway and pedestrians walking he street.

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5. ### Ray MarinaccioActive Member

The rotating disc idea sounds neat.
Motor driven belts would probably the way to go, they would be smoother than the stepper motor.
I'll have to think about how to make them get across the track. I don't know if modifying the bottom of the track would be an option, have to think about it.
Would a Hall affect sensor detect one of the cars?
6. ### PitchwifeDreamer

The problem with using a Hall effect transistor as a sensor is with the polarity of the premenent magnets in the slot cars.

I'll grant you that I'm no EE but as I understand the working of a HET, it is turned on when the south pole of a magnet passes by it. Since the slot car motors two magnets are mounted towads the front and back and each one has both north and south poles I'm not sure what efffect it would have on a sensor like that.

All I know for sure is that when one of these tiny magnets is under the track next to where the slot is, it has substansial movement when a car passes overhead. I tried it with several different types of cars just to make sure that it was sensitive to all of them and got a positive result each time. They are only 3/16" x 3/8" x .05" so will fit almost anywhere. If they were attached to a belt by a drop of glue or whatever in the center, leaving the ends free they should ride over pulleys or whatever they were mounted on.

I am a firm proponant of the KISS school of thought. these seem to be worth looking into, plus they have the advantage of being fairly inexpensive.
7. ### Sir_PrizeMember

There is an issue of MR that talks 'bout doing what you speak of.
I'll check tonight the specifics of the article, if you'd like.
It also talks about putting gloss on things to make look like the
storm had passed by. It all seemed pretty neat.

Cool Stuff ya' got going.
8. ### PitchwifeDreamer

That would be great Ken. I can use all of the input I get. The only difference would be that my storm is one of those distant ones that happen in the summer and usually doesn't even produce rain. However the weather can be fickle.
9. ### Sir_PrizeMember

I'll see to it tonight.