Homebrew PCBs

Must be that time of year. Wasn't it the same time last year? ;')

I moved it to Files when you first uploaded it to Photos, because
Photos will only allow everyone (but the moderator and the uploader)
to see a puny 300x400 image. And I wanted everyone to see it well, as
it is a very nice setup. I'm going to leave it in Photos with a note
to check Files for a closer view and more details.

It's here as an 800x600 image along with a GIF of the 400Hz generator
to drive the quill motor and a text file describing it:
<http://groups.yahoo.com/group/Homebrew_PCBs/files/Homemade%20PCB%20equipment/>

Very cool, an old Commodore PET computer controls it. Or controlled.

Hey, Jan, do you think it would be difficult to tranfer the program to
a Commodore 64? They are pretty plentiful, I'm in a Commodore64/Amiga
club and can probably find one for you cheap or cost of postage.

Please feel free to upload more details to that folder in Files.

Steve

--- In Homebrew_PCBs@yahoogroups.com, "Jan Rowland" <JanRwl@A...> wrote:
> I had been thinking I had ALREADY added this [subject] photo to the 
> group, but, well, guess it's Alzheimer's!  This quill has a 400 Hz. 
> 12,000 RPM AC motor in it.  Some machining to replace 1/4" shaft 
> on "bottom end" of motor with 1/8" collet/nut!  And ABEC-7 bearings.  
> That "quill motor" is powered by simple "push-pull" 400 Hz 
> multivibrator and 95 VA transformer purpose-wound for the 
> application.   I had used the old PET you see for years, but the last 
> of several I had on hand finally gave-in to alpha-particles, so I'm 
> slowly getting around to converting the 8-bit interface (yep, just a 
> 9-wire cable to puter!) to work through a PC parallel printer-port.  
> 
> The little blue motor atop the quill is a Slo-Syn 72 RPM SS-25 that 
> rolls a tiny cam-follower roller around a 1/4" pitch helix.  So the 
> quill-travel is abotu 0.24".  The quill can "do a hole" or "go down 
> and stay until told to return to "home".  This latter way, the 
> machine can engrave.  
> 
> The screws are 1/2" lead (1/8" pitch/4-start) stub-ACME.  Thomson 
> linear ball-bearings/ways.  Baltic birch base.  Formica-covered top.  
> 
> Can do about 3000 holes per hour, drill-rate.  (one bit-size!  Takes 
> time to change bits!)                  Jan Rowland