#garfield Logs

Jun 27 2021

12:35 AM rue_mohr: Tom_L,
12:43 AM rue_mohr: well
12:43 AM rue_mohr: I got a sensor on the rotation axis of the cnc
12:43 AM rue_mohr: er
12:43 AM rue_mohr: sorry,
12:43 AM rue_mohr: rotation axis of the tilt and pan mirror
12:43 AM rue_mohr: me and ma attacked the yard and reclaimed a lot of it
12:43 AM aandrew: I bet your property can turn into quite a jungle if you don't stay on top of it
12:43 AM rue_mohr: yea it goes quick
12:43 AM aandrew: the very brief tour I took of that area seemed like nature was kind of pissed off that people had claimed bits of it
12:43 AM rue_mohr: I got parts for doing the wifi driveway thing, but I got the wrong size pipe, 1/2" instead of 3/4"
12:47 AM aandrew: aha
12:48 AM aandrew: wrong size pipe for the power? or are you attempting to tunnel the 2.4GHz signal back via waveguide? :-)
12:49 AM aandrew: amazon is amazing most of the time, but today one of their couriers just pissed me off
12:49 AM aandrew: an order came in two shipments, both said they'd deliver today. One did deliver, the other sent an update at 8pm saying "delivery attempt failed; could not gain access to the property"
12:49 AM rue_mohr: no
12:50 AM rue_mohr: the conduit from the drive ways is 3/4" and I thought it was 1/2" I need to put a box on it on the shop wall to house the wifi module
12:50 AM rue_mohr: I hve the wrong size pipe
12:50 AM aandrew: and that just pissed me off, becuase nobody attempted anything. You didn't make the delivery, no big deal, shit happens, but this "I tried but the property owner prevented it" rubs me the wrong way
12:51 AM rue_mohr: this welding timer controller is going to drive me crazy
12:52 AM rue_mohr: i'm trying to NOT use a microcontroller
12:52 AM aandrew: heh
12:52 AM rue_mohr: I want it to do a 20ms pulse when you push the button and then do nothing for up to 3 seconds AFTER you let your finger off the button
12:52 AM rue_mohr: monostables suck
12:53 AM rue_mohr: they typically retrigger, so your input pulse MUST be shorter than the output pulse
12:53 AM aandrew: before i won the photodiode war I was going to use a Yup (or a modern equivalent) to briefly short out the photodiode for a few microseconds when the ADC's "data ready" signal asserted
12:53 AM rue_mohr: cool
12:53 AM rue_mohr: I can never remember the name of that switching amplifier
12:54 AM aandrew: but after screwing around with ltspice and reading a ton, it turns out the photodiode's shunt capacitance isn't the issue at all, it was my feedback capacitance slowing the response down
12:54 AM rue_mohr: you mentioned that
12:55 AM aandrew: went from about a msec to 50usec just by changing that cap
12:55 AM aandrew: I always thought a TIA was a specific design of op amp, but it's not, it's a specific design of opamp CIRCUIT
12:56 AM rue_mohr: isnt' analog evil
12:56 AM rue_mohr: ?
12:56 AM aandrew: no, I like the challenge but do not feel overly competent with it
12:58 AM aandrew: anyway, it's late, I should sleep
03:05 AM rue_mohr: 1am...
03:05 AM rue_mohr: the tabbing spot welder timer works
03:05 AM rue_mohr: and the ssr isn't locking up
03:42 AM rue_mohr: hah morning polprog
03:42 AM polprog: Morning rue
03:42 AM polprog: nice welder :)
03:42 AM rue_mohr: hah, completely bojangled
03:42 AM rue_mohr: I'll fix that, whats important is that its working
03:42 AM rue_mohr: at some basic level
03:43 AM rue_mohr: I suppose I'll etch a pcb for it
03:43 AM polprog: Im getting some new clad next week
03:44 AM polprog: going for a small vacation now
03:44 AM polprog: a day or two
03:44 AM rue_mohr: oh we will never get to work on circuits togethor
03:47 AM polprog: we do
03:47 AM polprog: just not recently
03:47 AM polprog: but we will when im back
03:48 AM rue_mohr: I think I got some 741G14s
03:49 AM rue_mohr: for oscillators
03:55 AM polprog: whats G?
04:20 AM rue_shop3: 1 gate
04:20 AM rue_shop3: huh, there is a retrigger issue somewhere
04:20 AM rue_shop3: I'm gonna sleep
04:45 AM Tom_L: :/
02:08 PM rue_shop3: ok, another crazy hot day
03:26 PM Tom_L: adjustments screwed up A12 setup
03:27 PM Tom_L: probably need to recut the visejaws
03:47 PM rue_shop3: were you able to get it trammed any?
04:09 PM Tom_L: i think it's better
04:10 PM Tom_L: won't know until i run the dial over the table and run a few parts
04:15 PM Tom_L: hopefully it will be better in the end
04:16 PM Tom_L: we're only after a few thousandths
07:33 PM rue_mohr: working on a pcb
07:33 PM rue_mohr: see if everything still works for etching
08:08 PM Tom_L: running part #2 after recutting softjaws
08:08 PM Tom_L: taking the adjutment out i'd put in prior to tramming
08:32 PM rue_mohr: did you do a software tramming correction?
09:10 PM aandrew: rue_mohr: I love the various 1G parts
09:10 PM aandrew: I think it's the 97 that I use ALL THE TIME
09:11 PM aandrew: I haven't looked but something that took something like the 97 and added a D FF would be amazing
09:11 PM aandrew: when you need just one bit
09:48 PM Tom_L: rue_mohr,
09:50 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A12_New/A12_batch.jpg
10:17 PM rue_mohr: Tom_L, hah, thats quite a run!
10:17 PM Tom_L: most of that this evening
10:17 PM Tom_L: they look pretty good
10:18 PM Tom_L: the slot cutter is sure noisy but does a nice job
10:18 PM rue_mohr: they do.
10:18 PM rue_mohr: noisy?
10:18 PM rue_mohr: bit of a howl?
10:18 PM Tom_L: like a jack hammer :)
10:18 PM rue_mohr: oof
10:19 PM Tom_L: they're known for that
10:19 PM Tom_L: i did a video.. you can listen
10:20 PM Tom_L: https://www.youtube.com/watch?v=Ls1XabACpKI
10:20 PM Tom_L: those damn led lights make the camera flicker
10:22 PM rue_mohr: oh its really low rpm
10:22 PM Tom_L: 2000
10:22 PM Tom_L: F5 ipm
10:23 PM rue_mohr: cool
10:23 PM rue_mohr: not seen something like that
10:23 PM rue_mohr: how do you program the path?
10:24 PM Tom_L: just a cutter offset from the profile
10:24 PM Tom_L: i thought i took a pic
10:25 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A12_New/A12_Position1.jpg
10:25 PM Tom_L: you can barely see the green line on the part but the yellow is the offset path
10:26 PM Tom_L: then i offset from it .0625 x 2 to break it up a little
10:27 PM Tom_L: you gotta be a little more careful with cutters like that so that you've cleared the part before you raise it up :)
10:32 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A12_New/A12_Position1a.jpg
10:32 PM Tom_L: after adding the extra 2
10:33 PM Tom_L: i could do it in 2 but it's a little easier on the cutter
10:38 PM Tom_L: the SFM on that cutter is 530
10:38 PM Tom_L: doesn't seem fast but you figure the diameter and the SFM goes up quick
10:39 PM Tom_L: in contrast, the SFM on the main profile cutter is 171
10:40 PM rue_mohr: but do you give it the finisehed profile, then tell it to cut full depth?
10:41 PM rue_mohr: or does it have a setting for saws like that?
10:41 PM Tom_L: no, i program it just like any cutter but with a radius offset
10:41 PM Tom_L: which would be .500:
10:41 PM Tom_L: "
10:41 PM Tom_L: then i offset from that final cut .0625 for the other 2
10:42 PM Tom_L: yes it gets programmed with the finish profile but with the offset added in
10:43 PM rue_mohr: huh
10:43 PM Tom_L: stop by, i'll let you run one
10:44 PM Tom_L: the cad cam handles the offsets for me, i just tell it how much
10:45 PM Tom_L: i extend that inside profile beyond the part though so it will clear the part