Lottsa fun and creative projects here:
- posted
6 years ago
Lottsa fun and creative projects here:
what a crap website.
It's not for your kind.
"The company was founded and is led by four graduates of the Royal College of Art and Imperial College London alongside a non-executive board and a number of industry advisors."
They don't mention sheet resistivity, probably because they don't understand the concept.
-- John Larkin Highland Technology, Inc picosecond timing precision measurement
I had a hell of time finding the data sheet on the artistic web pile: They spec sheet resistance: 55 ohms/square at 50 micron film thickness. or: Approximately 32 ohms/square when using a brush or manual screen printing. Nice ink if you want to make a potentiometer. It's obviously not doped with silver flakes or nano particles or the sheet resistance would probably be around 40 milliohms/square.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
At that rate, Teledeltos paper would be more useful for modeling/mapping fields...
...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et |
I didn't bother searching but my initial guess on seeing it was that it was likely ye olde aquadag.
NT
I had to dgi for the data sheet
And then this,
Clearly they don't know about testing to destruction...
George H.
They're arts people so don't expect to get blown away by overly technical white papers. They will deliver on the creative applications side of things though.
A few decades ago an IC professor had a neat observation about industrial designers...
If you ask an industrial designer to design an egg - the averages ones will produce something the right size and colour - the good ones will produce something the right weight - none will produce something with edible contents
"Air-dried ~800 ohms per square" That's 14 times more than 55 ohms/square. It's not the same stuff unless they threw some powdered metal into the mix. Or, maybe they used flake graphite instead of finely powdered graphite, which would lower the sheet resistance.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
at what thickness it doesn't say, making the comparison almost meaningless.
NT
If you want to know more about it, listen to this podcast:
If we were talking sub 50% difference I might have agreed with you, but
14 times?-- Mike Perkins Video Solutions Ltd
How about 2.7 times?
800 ohms/square and 14 times might be a bit high. From the Aquadag data sheet:Brush 1:1 Air dry 300 Ohm/square * Ratio expressed as grams of Aquadag E to grams of diluting water.
So, we have: Electric Paint 55 ohms/square at 50 microns thickness Aquadag 300 ohms/square at 25 microns thickness If I take two Aquadag PCB traces and lay them one on top of each other, I get a convenient 50 microns thickness and half the sheet resistance[1].
At 50 microns, that yields: Aquadag 150 ohms/square at 50 microns thickness and a ratio of: 150 / 55 = 2.7:1
More numbers from a different data sheet: Application Method* Thickness (Dry) Cure Cycle Resistance
Again, using the brush numbers, and stacking 7 traces that are 7.5 microns thick on top of each other to get a 52.5 microns thickness, the 1000 ohms/square sheet resistance becomes: 1000 / 7 = 149 ohms/square and a ratio of: 149 / 55 = 2.7:1 which is the same as the first Aquadag data sheet. That's close enough that doping the Aquadag graphite with something more conductive (silver?) might bring the sheet resistance down to the level of the Electric Paint. I don't know and can't tell without analyzing the ink and making some measurements. If it is doped, I could possibly remove the graphite particles with flocculation (causing the graphite particles to clump and precipitate) and then centrifuge what's left leaving whatever powdered metal might have been used to enhance the conductivity.
[1] This is not really true as the sheet resistance to thickness is a hyperbolic relationship, but is close enough to linear for large length/width ratios. For example:-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
That's probably true if management assumed that everyone involved knew that eggs were only made to be eaten by humans. Given the apparent lack of detail in the design specification, it's equally likely that the egg was designed to be pre-paint by numbers for Easter, arrive pre-hard boiled, include a door to provide an easy exit for the chick, color coded for easy sorting, and so on. Industrial designers are expected to have a good imagination and when the design specs are vague or lacking, one can be certain that this imagination will be fully utilized.
This cartoon has been around for a long time, and still applies nicely:
Would you eat a square (or cubic) egg?
For what little it's worth, I functioned as something resembling an industrial designer while designing marine radios. At the time, the company did not have a dedicated industrial designer, which gave everyone an opportunity to contribute their mistakes to the product design. What I saw most often were impressive concepts that couldn't be built or were in some way difficult to use.
The problem is especially prevalent in bicycle design, where absurd and impractical concepts are the norm: Would ride or buy one of these?
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
Yep. My wife has a gadget that forms boiled eggs into cubes. (They don't roll around on your plate ;-)
Actually...
looks pretty viable. ...Jim Thompson
-- | James E.Thompson | mens | | Analog Innovations | et |
Oh. I was wondering how it was done. I thought they put the hen in a cubical box, and it laid egg cubes.
Have you considered buying plates with detents instead of mutilating the egg (or the chicken)?
That's a fairly mild example. These are more common:
The Shift Bicycle is actually a tricycle. It's intended for older riders, and allegedly offers more stability than a two wheeler. Such designs are usually the result of trying to solve one problem, at the expense of other things that had previously worked just fine. The bicycle has been around for so long, that all of the features have been repeatedly optimized and tested. Trying to change any single component invariably requires changes in many other design components, resulting in some rather strange looking machines.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
I see your electric paint and I raise with Electroluminescent Paint...
Made near my home.
Steve
Very cool, but also pricey: $500 for 4 oz (118ml) sample kit in one color.
I guess I should also mention that the electric paint was intended for making PCB's, not garish motor vehicles.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com
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