Date: Wed, 2 Jun 2010 12:57:17 -
Author: --- "Miglus, Vacek"
Subject: Re: Bits for obsolete Pasco apparatus
If you have at least one example of what you need, then contact a machine shop, preferably one associated with a university so they know how to deal with weird requests, send them the example and they should be able to duplicate your pin, and maybe your third disc.
These services won't be free, but it will get you up and running for a lot less than buying new equipment and rewriting your labs.
On Jun 2, 2010, at 11:05 AM, Donald Smith wrote:
> We have the Pasco rotational dynamics apparatus
> here at my school, but my students have managed to lose a lot of the
> little bits for it. Actually, to be fair to them, what I think
> happened was someone raided the lab for empty boxes, perhaps to help
> with a move, and didn't realize that some of the boxes they took
> weren't actually empty but were used for equipment storage. Several
> other of our storage boxes, for which the associated apparatus was out
> and in use, disappeared about the same time. So my guess is they took
> an apparently (mostly) empty box, but it had the third disc, the
> little pins, and all the other little odds and ends for the
> experiments. So all I have now is the base and two of the discs.
> Without the pins, there's not a whole lot my students can do with this
> apparatus, and Pasco doesn't make it any more. So I am faced with
> trying to make a new pin for it, but I am a little worried about
> making a pin that will both 1. block the air coming up from below so
> the top disc floats, and 2. pull out smoothly enough that it doesn't
> exert any significant torque on the disc in the process.
> Has anyone else already done this? Do you have any advice for me in
> terms of what to try and what to avoid? Are there any good substitute
> objects that I can just buy at a craft or hardware store? Maybe it's
> really easy, and if so, I apologize for wasting your time, but if you
> could save me a lot of trial and error frustration I would be *very*