Homebrew PCBs

Derward,

I investigated spin coating a bit further,

http://en.wikipedia.org/wiki/Spin_coating
http://www.clean.cise.columbia.edu/process/spintheory.pdf%20%20
http://www.ece.gatech.edu/research/labs/vc/packaging/theory/spin_theory.html

It seems as though 1200 -4800 rpm is the approximate speed of rotation. 

If you can do this at 45 rpm, This an almost ready made solution,

http://www.allelectronics.com/make-a-store/item/DCM-351/24-VDC-GEAR-MOTOR-W/-TURNTABLE/1.html

However, my reading of the above references suggests that the thickness of the coating is proportional to the speed and viscosity. I may try the allelectronics motor, but I like the fan solution of designer_craig. 

Here is another take on the fan approach,

http://www.chemistry-blog.com/2007/01/13/pimp-my-spin-coater/

Quote from the answer to a comment question:

"I use velcro to hold the samples down. The pc fan is an Antec tricolor pc fan. It takes DC Power, we can vary it from 0-12V depending what speed is needed. The fan was able to spin from 0 rpm up to around 2500 rpm."

From the photo, It doesn't appear that he is even using a a platter.

Baxter



--- In Homebrew_PCBs@yahoogroups.com, "Derward Myrick" <wdmyrick@...> wrote:
>
> 
> Back in the ealy 1960s I worked at a Company that used a record player turntable
> at 45 rpm.  Worked great.
> 
> Derward Myrick   KD5WWI
>