#garfield Logs

Apr 03 2020

04:11 AM Tom_L: 29°F brrr
11:04 AM Tom_L: https://www.youtube.com/watch?v=_atw3e0nIrg
02:51 PM rue_mohr: zhanx_,
07:16 PM rue_mohr: ShopMoon,
07:24 PM Tom_L: what's goin on in avr?
08:50 PM rue_mohr: life
08:50 PM rue_mohr: more than usual
08:50 PM rue_mohr: you notice more life in #robotics too?
09:40 PM Tom_L: just a couple or three
09:41 PM Tom_L: whole irc is mostly dead during the day
09:51 PM rue_shop2: "RX errors 10831"
09:51 PM rue_shop2: bad network connection on this machine
09:51 PM rue_shop2: looks like its the cable
09:52 PM rue_shop2: need to cough up a Z axis for the cnc
09:52 PM rue_shop2: I needed a ruler
09:52 PM rue_shop2: and gloves, damn its cold
09:52 PM rue_shop2: or the circ in my fingers sucks
09:52 PM rue_shop2: zhanx_,
09:52 PM rue_shop2: ShopMoon,
09:53 PM pinkmutt: is anyone online?
09:53 PM rue_shop2: ... who are you?
09:54 PM rue_shop2: anyhow, Z axis
09:54 PM rue_shop2: I wonder if I shouldn't have tried to lighten my orig one
09:55 PM rue_shop2: london?
09:55 PM rue_shop2: cant be right
09:56 PM Tom_L: so
09:56 PM Tom_L: what you gonna work on tonight?
09:57 PM Tom_L: and who is pinkmutt?
09:57 PM rue_shop2: I dont know if I can stay awake
09:57 PM rue_shop2: no idea, I'm trying to find out, stupid programs aren't installed on this machine
09:57 PM Tom_L: i wish i had a handfull of 123 blocks
09:57 PM Tom_L: i think i could map the screws a little closer
09:58 PM rue_shop2: comcast, thats a bad sign
09:58 PM Tom_L: i have a couple
09:59 PM Tom_L: the longest one is 17.75"
09:59 PM rue_shop2: ok
09:59 PM rue_shop2: so if its out by 5 thou/0.5"
09:59 PM Tom_L: using a last word indicator would be more accurate i think
10:00 PM Tom_L: but i'm not sure if it is and i still can't figure out why the Z is off that much
10:00 PM Tom_L: the other 2 are pretty close
10:00 PM rue_shop2: hmm, over 18" the total error would be less than 0.2"
10:01 PM rue_shop2: but you still might be able to see it
10:01 PM Tom_L: i need to be able to measure the total travel from 0 to 17.5
10:01 PM rue_shop2: take an engraving point
10:01 PM rue_shop2: and use a tape measure, over the whole distance, see how far out it looks
10:01 PM rue_shop2: you can see 0.1"
10:01 PM Tom_L: i thought about rigging up a calipers
10:02 PM rue_shop2: tape measure
10:02 PM rue_shop2: if its out by 0.1" you can clearly see it
10:02 PM Tom_L: i don't think it's _that_ far off
10:02 PM rue_shop2: didn't you say 5 thou over 0.5"?
10:03 PM Tom_L: some were .001 some were 0.00
10:03 PM rue_shop2: oh
10:03 PM Tom_L: some .002
10:03 PM Tom_L: but the method of measure is in question
10:03 PM Tom_L: that's why i'm trying to come up with a different way
10:03 PM rue_shop2: I wonder how, on machines a few hndred feet long, they deal with thermal size changes
10:04 PM Tom_L: stacking up 123 blocks and moving a known distance to the end of one with the last word indicator might be more accurate
10:04 PM Tom_L: then shortening the stack 1" at a time
10:04 PM Tom_L: they use glass scales
10:04 PM rue_shop2: z axis
10:04 PM rue_shop2: over, whats my z
10:05 PM Tom_L: i know on Z i can go to 2:1 ratio but i don't think i got pulleys for 1:1
10:05 PM Tom_L: i think the stepper is plenty strong for 1:1
10:06 PM Tom_L: but i didn't know at the time
10:06 PM Tom_L: if this cold spell goes away maybe i'll try something tomorrow
10:07 PM Tom_L: on X and Y i got some overshoot and some undershoot so it was a fair balance overall
10:08 PM Tom_L: there again i question the measuring method
10:08 PM rue_shop2: my Z is 6"
10:08 PM Tom_L: i think mine is 7
10:09 PM rue_shop2: oh, thought you had a lot more
10:09 PM Tom_L: i wish i did
10:10 PM Tom_L: i raised Z 2" from the original design so more of it was useable
10:10 PM Tom_L: i could go higher and still be ok
10:11 PM rue_shop2: I dont expect to use all mine
10:12 PM Tom_L: https://www.ebay.com/itm/2-3Axis-DRO-Digital-Readout-for-Milling-Lathe-Machine-Linear-Glass-Scales/392619866552?epid=13022805422&hash=item5b69f7b9b8:m:m1msCDC61Ngw2pcioUvYfBQ
10:12 PM rue_shop2: maybe ... plastic....
10:13 PM rue_shop2: I need Z sliders
10:13 PM rue_shop2: no I'm not buying them
10:14 PM rue_shop2: I have a throbing headache and I'm half asleep
10:14 PM rue_shop2: which is almost as good as I get recently
10:14 PM rue_shop2: it zerps any kinda usefull thinking
10:16 PM rue_shop2: part of the problem is that the motor hangs down 6" from the slider
10:16 PM rue_shop2: which means that extended 6", the sider has to be really ridgid
10:16 PM Tom_L: z is always a problem that way
10:17 PM rue_shop2: easier if you make it static, and move the whole Y axis up/down
10:17 PM rue_shop2: a static overhang of 6" is easier
10:21 PM rue_shop2: and build-out is a problem
10:21 PM rue_shop2: I think if the Z is more than 2" out, I lose from my 8'
10:21 PM Tom_L: i forget how far mine sticks out but i know i re'did it and made it longer than the first round
10:21 PM Tom_L: but you're doing a gantry and i didn't
10:22 PM rue_shop2: I need to get to the point its working, so I can be just modifying it
10:22 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Z_Column_Standoff2.jpg
10:23 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Z_Column_Standoff1.jpg
10:23 PM Tom_L: 4" thickwall
10:23 PM Tom_L: the plate is more than 1/4" maybe 5/16
10:24 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Z_Column2.jpg
10:24 PM Tom_L: one of the early mockups
10:25 PM Tom_L: i got rid of the rusted plate after i found that brand new scrap
10:26 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Welding/Frame_Weld1.jpg
10:26 PM Tom_L: used the new as a workplate until i cut it up
10:26 PM Tom_L: still have alot of it
10:26 PM rue_shop2: from my Y rail to the middle of the router cant be more than 4"
10:26 PM Tom_L: you ended up with a piece of it :D
10:27 PM rue_shop2: :)
10:27 PM rue_shop2: I cant think
10:27 PM rue_shop2: I really wish I could tink
10:31 PM rue_shop2: I suppose I go with plastic and make the first priority to get the machine going
10:31 PM Tom_L: speaking of, did you see that yt build?
10:31 PM rue_shop2: no
10:32 PM Tom_L: https://www.youtube.com/watch?v=_atw3e0nIrg
10:32 PM Tom_L: skip thru it
10:32 PM Tom_L: i wouldn't watch the whole thing
10:33 PM rue_shop2: seen that design around
10:35 PM rue_shop2: but it does tell me I can dial my standards down a long way before I hit faulure
10:36 PM Tom_L: hah
10:36 PM Tom_L: i wouldn't build one like it but was surprised how well it did actually
10:44 PM rue_shop2: I think part of my knew the pandemic was comming
10:44 PM rue_shop2: the last year and a half a been frantic to make sure I"m stocked up on everything I might ever need
10:45 PM Tom_L: now you don't have any wiggle room
10:46 PM rue_shop2: I got a lot of stuff
10:47 PM rue_shop2: I just cant stay awake to use it
10:47 PM rue_shop2: I need to work out this robot thing
10:47 PM Tom_L: that's a problem
10:49 PM rue_shop2: its like standing on one side of a huge channel
10:49 PM rue_shop2: me here, me there, need to find a route across
10:51 PM rue_shop2: if I break out my welder now, I wonder if I can get anything usefull done here
10:51 PM rue_shop2: I'm verry askeep
10:51 PM Tom_L: no reason not to
10:52 PM Tom_L: start and see if you come alive
10:52 PM rue_shop2: trying to be usefull and it takes all my energy to keep my eyes open
10:53 PM Tom_L: glass must have a very low thermal expansion
10:53 PM rue_shop2: depends on the mix
10:53 PM rue_shop2: quartz is low
10:54 PM Tom_L: that's why glass scales are desireable for DRO
10:54 PM rue_shop2: pyrex is less low
10:54 PM rue_shop2: they probably need something that goes with the steel tho
10:54 PM rue_shop2: unless you let the end drift
10:55 PM Tom_L: it's mounted in a frame and probably is fixed on one end i suppose
10:55 PM Tom_L: i don't know much about them