Date: Thu, 04 Nov 1999 11:37:39 -0600

Author: "Ramon O. Torres-Isea"

Subject: Re: Airtracks



Mike I don't think we are talking about the same airtrack.
The Daedalon model that we have are the 2-m long
"Intermediate Airtracks" (Model EA-70, $500), which is reinforced.
The ones that you are describing seems to be the cheaper EA-01, $425.
With 32 of the EA-70's we have not detected problems of any type.

Daedalon also make an even more reinforced model
(with an I-beam, Models EA-75 through EA-78, $600 - $3100).
This type of reinforcement is needed, in opinion,
only if you use the longer models (2.5m -5.0m).

As far as the airsource being low noise, I have heard that
CENCO has a new airsource that is very quiet and only $199.00
(part # 33875). I have not tested it.

Ramon O. Torres-Isea
Coordinator, Physics Laboratories.
Department of Physics and Astronomy,
The University of Iowa.

Phone: 319-335-1754

Mike Ugawa wrote:
> I highly recommend the PASCO airtracks and air supply. They are a little
> more expensive than the low-cost Daedalon ones, but are worth the
> difference in price. I have one PASCO unit that I have had for a few
> years, and it's still working great. The PASCO air source is nice and
> quiet, and it's output is adjustable.
> Last year I purchased eight of the low-cost Daedalon tracks and four air
> supplies. I made the decision based upon cost--and I really regret it. The
> air supplies are so loud that my lab sounds like an airport runway when a
> 747 is taking off. My students and I have to shout at each other to
> communicate when the air supplies are running. As if this were not bad
> enough, all of the tracks are low in the middle. This makes doing a
> conservation of energy/momentum collision possible only when using one
> glider stationary in the middle, and measuring the final velocity of the
> outgoing glider at the same distance from the center as the incoming
> glider was when its initial velocity was measured. The dip in the middle
> means that a glider moving toward center will pick up speed, thus other
> less symmetric collisions will not yield good results. My colleagues find
> this limitation to be troublesome.
> When I spoke to Bud Brown, President/CEO of Daedalon, he told me that the
> low-cost tracks are designed with this slight dip in the middle. He
> claimed that having a rise in the middle would render the tracks useless
> in a wider range of contexts, which I suppose makes sense, but I want one
> that is FLAT, neither high nor low in the middle. This low-cost model does
> not have the stabilizing extra beam below the actual track as do the
> higher priced models that Daedalon offers.
> Bud actually was quite good about trying to help me out. He offered to let
> me excahnge the ones I had for the ones with the stabilizer beams, at a
> resonable upgrade cost, in spite of the fact that I had used the ones I
> had for a year. Unfortunately, the ones I could have gotten would have
> been longer, and would not have fit the space constraints I have at the
> stations in my lab. So, sadly, I'm stuck with what I have. I really wish I
> had gotten the PASCO tracks.
> Best wishes,
> Mike Ugawa
> St. Ignatius College Prep, San Francisco