#robotics Logs

Mar 21 2019

08:43 PM rue_mohr: mmm digital servo
08:47 PM zhanx: ?
08:47 PM rue_mohr: get the old code working for the cnc machine
08:47 PM zhanx: as in homemade?
08:47 PM rue_mohr: I think I'm gonna do an L293 as a temp driver
08:47 PM rue_mohr: yea
08:47 PM rue_mohr: got a motor with encoder, gonna throw my old PD code at it
08:49 PM Tom_L: 2000 is ~130 sfm which seems a bit high but i tried it and it didn't seem to mind it
08:49 PM zhanx: chart says 900-1422
08:50 PM Tom_L: i tried 1500 and it vibrated alot more
08:51 PM zhanx: wait i read the wrong line, 1625-2037 rpms
08:52 PM Tom_L: i was testing with a 2 flute carbide, i may get a couple 4 flute carbide for the job
08:52 PM Tom_L: it was an old bit too
08:53 PM Tom_L: wondering if hss may do better on mild steel than carbide
08:53 PM zhanx: .0002 feed rate per rotation
08:53 PM Tom_L: ~2 ipm
08:54 PM zhanx: my chart is older but still should be good
08:55 PM Tom_L: i get 2000 rpm .0003 per tooth @ 130 sfm
08:56 PM Tom_L: well, .00025
08:56 PM zhanx: should be .0002 but really that is close enough
08:57 PM zhanx: then you are good enough at .00025, i would not change it
08:57 PM Tom_L: someone suggested around 90 sfm
08:57 PM Tom_L: approx
09:00 PM zhanx: why you are low at 130 sfm 150 - 300 sfm is in the range i thought for mild steel
09:00 PM Tom_L: ok
09:01 PM Tom_L: i think i'm fairly close with what i have, just never ran that much steel
09:01 PM Tom_L: i'll use these numbers to calculate the rest of the tools
09:01 PM Tom_L: i certainly don't want to break the thread mill
09:01 PM zhanx: i did a lot of it in highschool but still remember the math on it
09:02 PM Tom_L: my cad cam will to the math, i just needed a starting point
09:02 PM Tom_L: i ran some tests on the mill to see approx
09:02 PM Tom_L: manually
09:03 PM zhanx: key is knowing your machine and adjusting off that, the charts are a guide really
09:03 PM Tom_L: i know
10:37 PM rue_mohr: transistor hunting, to-251
10:54 PM rue_mohr: ooo 2SB1203