--- In [EMAIL PROTECTED], "turbulatordude" <[EMAIL PROTECTED]> wrote: > > Hi all, > > I pulled apart an old HP plotter ...... > Has anyone ever tried to use the plotter motors ? > > Has anyone ever hacked the controller board for these for CNC use ? > Any ideas what to do with them ? > Since I have three more plotters I'm not sure if I should pull them > apart for parts or just junk them. > > Dave.
Dave, This is the idea that gave me the CNC bug many moons ago. I still haven't shaken it and a relapse was brought on recently with the imminent delivery of a free HP 7475A Graphics Plotter. I already received the (Operator's) Manual. Hopefully, the motors in mine are steppers, for simplicity. To keep things simple, I will use the output motor phase signals and add a simple Driver Stage (eg. Higher Voltage stage with 4x darlingtons to bigger steppers). I intend to stick with the HPGL and drive it as a Plotter as designed. The original cheap Plotter that I first played with was on a SHARP MZ700 64kB computer circa 1978. It had 4 wee coloured ballpoint pens in a rotating chamber. Motors were driven by 5V TTL Hi levels on the phase wires! A BASIC command such as "CIRCLE 5,46,0,360,0.2" (Draw a circle with centre at X=5,Y=46, Radius:123,Start Angle:0,End Angle:360,Step Angle:0.2 degrees) involved sending ASCII codes for "C","comma","5","comma","4","6","comma","0","comma","3","6","0","c omma","0",".","2" to an onboard interpreter). HPGL may well be interpreted onboard in vintage plotters in a similar way. Axis co-ordination being done onboard.(A reason to stick with that command format.) There are a few different ways of achieving extra controls. Pen- Up /Down is readily available (including successive Pen-Dns!)and the pen change movements can be modified also. (The SHARP simply drove the pen carousel against an off-plot-area stop with the pen up. Each motion against the stop indexed the carousel to the next pen by a simple mechanical ratchet.) Pen cleaning movement routines are often available for playing with, too. I scrapped the SHARP project because it only addressed -480 to +480 clicks on X-axis. HP7475A does -32767 to +32767 clicks per axis, so 32" at 0.001" resolution is possible! Don't throw those boards out yet! They may be smarter than you think. (Or throw them my way.) Anyone wanting to share manuals/info/hardware/ideas on plotters, please keep in touch. Hurry, though, because I just ordered a 4 axis Xylotex Driver, and am in danger of going mainstream unless encouraged. :) Cheers, Don. P.S. Photos will be forthcoming, Dave, but I don't seem able to post to Files area .... Addresses: FAQ: http://www.ktmarketing.com/faq.html FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ Post Messages: [EMAIL PROTECTED] Subscribe: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] [Moderators] URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO OFF Topic POSTS: General Machining If you wish to post on unlimited OT subjects goto: aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if you have trouble. http://www.metalworking.com/news_servers.html http://groups.yahoo.com/group/jobshophomeshop I consider this to be a sister site to the CCED group, as many of the same members are there, for OT subjects, that are not allowed on the CCED list. NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........ bill List Mom List Owner Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
