Back in the ealy 1960s I worked at a Company that used a record player turntable
at 45 rpm. Worked great.
Derward Myrick KD5WWI
----- Original Message -----
From: designer_craig
To: Homebrew_PCBs@yahoogroups.com
Sent: Saturday, April 17, 2010 7:26 PM
Subject: [Homebrew_PCBs] Re: My new photo resist spinner
Baxter,
Not sure what RPM the motor is running but its fairly fast. I control the speed by modulating the power button with my finger. Guess I need to figure out how to measure it.
You want to get the aluminum disk centered as much as possible. That issue came up when I went to attach the disk to the hub. How the devel am I going to get it centered? I couldn't see the hub and I had forgotten to drill a center hole in the disk while I was cutting it out on the lathe. I mixed up the JB-Weld and coated the top of the fan hub centering the disk by eye. Then I fixed a pencil to the box with some tape as a guide with the point close to the edge of the disk. Rotating the disk and hub by hand I was able to get the disk centered quite well, it runs nice and smooth with only a hint of vibration at full speed. The blank PCB is going to unbalance everything anyway. Did a lot of boards on my old spinner years back and almost never had a board fly off. Its a good idea to spin it up before you put on the resist just to test your positioning.
--- In Homebrew_PCBs@yahoogroups.com, "bebx2000" <bebx2000@...> wrote:
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