#linuxcnc Logs

Jul 20 2020

#linuxcnc Calendar

01:24 AM veegee: Loetmichel I checked the hoses on the forklift. Both hoses jerk when I actuate the lever
01:30 AM veegee: They jerk in one direction when I move the lever forward, and jerk in the other direction when I move the lever backwards
01:30 AM veegee: All other parts of the forklift seem to be working fine
01:30 AM veegee: JavaBean LFP _is_ LiFePO4
01:33 AM Loetmichel: veegee: then i would conclude that either the hydraulic ram is mechanically blocked (rust?) or has a failsafe valve that only allows operating it when one side has pressure and its stuck
01:34 AM Loetmichel: does it have a valve block on top of the ram? or do the hoses go into each end of the ram directly?
01:35 AM veegee: Loetmichel I should mention that normally both forks are supposed to move when you widen/squeeze them. But they don't necessarily move at the same speed in my experience anyway. When it was working, one of the forks would reach the end first and then the other would then get the increased pressure and move faster towards the end
01:35 AM Loetmichel: ah, so its two rams
01:35 AM Loetmichel: still that would be my explanation
01:36 AM veegee: ok I'll have to check that tomorrow morning. I'll take a full video and pictures.
01:36 AM Loetmichel: i know those "fork spreaders" with one ram in between and another one on a different slider that moves them "parallel" left/right
01:37 AM veegee: If it's two rams, it's strange that _both_ are not working
01:37 AM Loetmichel: ah, afterthought: sometimes they leave the blocking pins in, so if they are locked they may prevent the rams from moving the forks at all
01:37 AM veegee: When I moved them in closer all the way, that's actually when it stopped working, when both are at their narrowest position
01:38 AM veegee: blocking pins?
01:39 AM Loetmichel: the locking pins that are used for "manual" movement on forklifts without hydraulics for the fork "wideness"
01:39 AM Loetmichel: usually on top of the forks with a lever to unlock them
01:39 AM veegee: I definitely didn't touch anything near the forks, so if it had those pins, they may have fallen into the locked position on their own
01:39 AM veegee: Yeah my Hyster forklift that doesn't have fork spreaders has those pins
01:39 AM Loetmichel: yeah, that was the thought
01:40 AM veegee: I figured since this one has fork spreaders, it wouldn't have such a thing
01:40 AM Loetmichel: yea, was just an afterthought
01:40 AM veegee: But that's entirely possible, also given that they locked up at their narrowest point and not at some random position
01:41 AM veegee: Now that you mention it, the left fork reached its narrowest position first and locked into place while the right one moved. When the right side reached its narrowest position, that one locked up too. I didn't notice that at the time.
01:41 AM veegee: I really hope that's the case, would save a lot of trouble
02:17 AM pink_vampire: something is wrong with my Y axis.
02:18 AM pink_vampire: I'm getting like 0.2 backlash - no idea from where.
02:19 AM pink_vampire: first thing I did a took the gib apart
02:19 AM pink_vampire: put it back super tight- same 0.2 backlash
02:20 AM XXCoder: from screw itself?
02:20 AM XXCoder: screw block?
02:20 AM pink_vampire: no idea, I can't lift the table myself
02:21 AM XXCoder: probably could check couple spots by yourself
02:23 AM pink_vampire: I need to take the Y axis motor out.
02:23 AM pink_vampire: I with the screw was better supported
02:23 AM pink_vampire: wish*
02:29 AM XXCoder: dont know enough about design to really comment
02:55 AM Loetmichel: veegee: i only remember that when i operated a forklift that had spreaders that it goes "click... click..." every few inches of the spreader moving and investigating it i saw the locking pins for the forks still in place and just in the "unlocked" position.
02:56 AM Loetmichel: (cant remember which make though, it was red and dark gray)
03:13 AM pink_vampire: I took the motor out and the bearing housing,
03:16 AM pink_vampire: is that normal that I can tilt the ballscrew in the ballnut??
03:20 AM XXCoder: what you mean by tilt?
03:21 AM Loetmichel: no, thats NOT normal if you can move the ballscrew-nut in ANY way other than rotating it around the ballscrew.
03:37 AM pink_vampire: Loetmichel: LOL, so there is definitely something wrong with my ballscrew-nut
03:39 AM pink_vampire: what ballscrew-nut are you recommended?
03:44 AM XXCoder: it may be just question of retightening or changing bearings
03:50 AM pink_vampire: at this stage it is just the ballscrew and the ballnut
03:53 AM Loetmichel: XXCoder: i doubt that any movement that is visible/feelable can be redeemed by tightening the nut down
03:53 AM XXCoder: so its shot by wearing down
03:53 AM Loetmichel: i would think there have to be at least a whole turn of balls missing for it to "wobble" around#
03:55 AM Loetmichel: pink_vampire: if you feel adventourus: remove the nut from the ballscrew, clean
03:56 AM XXCoder: as yeah repack and all that
03:56 AM pink_vampire: let me make a video
03:57 AM XXCoder: *yeah as well as repack and all that
04:09 AM Loetmichel: be careful though: had a couple of "64 pick-up" games when dismantling those ballscrews.
04:09 AM Loetmichel: kinda tiring to seach for ~2mm diameter stell balls all over a concrete floor workshop
04:10 AM Loetmichel: also google for the correct count and diameter of balls inside the nut, and WHERE they are.
04:11 AM XXCoder: yep if I recall its orginal so hers should be either high quality and really shot or still fine but worn elsewhere
04:11 AM Loetmichel: some ballscrew nut designs are a bit convolutet and not really intuitive at first glance.
04:11 AM XXCoder: theres "nut transfer" 3d printed opbjects too
04:11 AM XXCoder: so can move into it to avoid losing any balls
04:11 AM pink_vampire: ok it is sooo hard to video this thing
04:11 AM XXCoder: return same thing
04:12 AM Loetmichel: yeah, doesent help if you want to clean the nut inside and remove all the balls
04:12 AM XXCoder: no its for removal and resert only
04:12 AM Loetmichel: indeed
04:12 AM XXCoder: you transfer it and move it to bin, remove it and process it
04:12 AM XXCoder: repack it then go back move it in
04:12 AM Loetmichel: ah, you meant so you dont lose any balls on the way to the cleaning vat?
04:12 AM XXCoder: yeah
04:13 AM pink_vampire: but if balls + junk = play, how balls - junk will be = less play??
04:13 AM XXCoder: its nifty item
04:13 AM XXCoder: pink thats the question of condition of balls and nut
04:13 AM Loetmichel: pink_vampire: i would imagine the junk has pushed some of the balls into the wrong thread. there are some ballscrew nuts that use only every second turn
04:14 AM Loetmichel: also look out for worn ball reversers if they are made of plastic
04:14 AM Loetmichel: thats why i said: google where the balls are MEANT to be before dismantling
04:14 AM pink_vampire: this is the 1605 ballscrew-nut
04:15 AM pink_vampire: and it use 1/8" steel balls
04:15 AM Loetmichel: with the two tubes on the outside as reversers?
04:15 AM Loetmichel: round nut with a flange on one side?
04:15 AM XXCoder: Loetmichel: https://www.thingiverse.com/thing:917488
04:15 AM XXCoder: nothing complex needed. though I would add base so it has spot to rest on.
04:16 AM pink_vampire: and ad far as I remember I did loaded them up with more balls, because originally some was missing.
04:17 AM XXCoder: https://www.thingiverse.com/thing:1806610 that one seems better for transferring too
04:17 AM Loetmichel: pink_vampire: there are many different ones of those 1605. these here for example seem to have THREE plastic reversers and use only three revolutions of the thread: https://de.aliexpress.com/item/4001041570576.html
04:18 AM Loetmichel: and there are some that have ONE or TWO reverser tubes made of steel that go the full length of the nut
04:22 AM pink_vampire: mine have 3 orange plastic things look like this one https://www.ebay.com/itm/402324404449
04:23 AM XXCoder: pink if I recall right you also measured all balls?
04:23 AM XXCoder: it fell all within tol right?
04:25 AM pink_vampire: yeah
04:25 AM pink_vampire: I know I got a bag full of 1/8" balls just for that
04:25 AM pink_vampire: and I even use then years later for alot of stuff.
04:27 AM Loetmichel: pink_vampire: i would suspect that either the balls are in the wrong thread or the reversers are damaged so the balls can "change threads" or the balls worn down into a paste
04:27 AM Loetmichel: these three orange things are the reversers (probably) that move the balls back into the thread.
04:32 AM pink_vampire: https://www.youtube.com/watch?v=VDYFgwNOlo8
04:32 AM pink_vampire: video of the problem
04:33 AM pink_vampire: XXCoder: Loetmichel ^
04:33 AM XXCoder: looking
04:33 AM XXCoder: its definitely moving
04:34 AM Loetmichel: "ach du schei**e!"
04:35 AM Loetmichel: sorry, "oh fu**!". thats bad. either the balls are totally ground down or they have the wrong diameter altogehter
04:36 AM pink_vampire: so it is 100% ballscrew - nut problem, and this is what make that 0.2mm backlash?
04:38 AM Loetmichel: yes, probably
04:42 AM pink_vampire: ok, what is consider a better replacement?
04:42 AM XXCoder: probably should give it a checkover
04:42 AM XXCoder: see what is causing it
04:43 AM XXCoder: after all, new one might break under same condition if root cause is not nut or screw.
04:43 AM XXCoder: suggest *really* clean it and see what is going on
04:44 AM pink_vampire: not sure what to do
04:45 AM pink_vampire: at this point I want to replace the ball screw and the ball nut, with something better, after all I have the machine from 2014..
04:45 AM XXCoder: see what I just said :)
04:45 AM XXCoder: the first step is to clean everything up, use somic cleaner if have to, then see what the condition is.
04:47 AM pink_vampire: I don't want to take it apart before I have some replacement one.
04:47 AM pink_vampire: so what is a good replacement for it?
04:47 AM XXCoder: dunno
04:47 AM pink_vampire: to get the same one?
04:48 AM XXCoder: i'm pretty good on troubleshooting but im no machine designer :D
04:57 AM pink_vampire: Loetmichel: ^
04:57 AM pink_vampire: any idea?
05:12 AM JT-Cave: morning
05:14 AM XXCoder: hey jt
05:17 AM JT-Cave: got started milling boards from that huge chunk of red oak but I had to noddle it in half to fit into the bandsaw mill
05:20 AM XXCoder: big eh
05:20 AM JT-Cave: widest the mill will take is 22" and my wood was 24" x 12" so I cut it down to 12x12
05:30 AM Loetmichel: pink_vampire: i would get the same ballscrew and replace it.
05:41 AM XXCoder: i would check old one first and find WHY it broke
05:41 AM XXCoder: so you avoid new one breaking like old obe
05:42 AM XXCoder: or order new one, and when it arrives dont install it but check old first
05:45 AM pink_vampire: Loetmichel: the one I have is single nut, I think to go with double nut
05:46 AM Loetmichel: pink_vampire: thats not neccessary
05:46 AM Loetmichel: those nuts should be without backlash
05:46 AM Loetmichel: you dont need a second nut
05:47 AM * Loetmichel thinks that maybe the alignment of ballscrew and nut is off so there is excessive wear
05:47 AM Loetmichel: is that a 6040 type machine?
05:48 AM pink_vampire: no, this is a mill, but it use the same ball screw as the 6040
05:50 AM pink_vampire: Loetmichel: this is a very good point
05:50 AM pink_vampire: the screw is only supported on one side
05:51 AM Loetmichel: can you move the axis all the way to the bearing side?
05:52 AM Loetmichel: and then check if the bearing "falls" into its seat without causing the ballscrew to move on the other end?
05:52 AM Loetmichel: aka: perfectly aligned.
05:53 AM Loetmichel: if it moves more than a mm on the other end its highly likely that that misalignment caused the wear.
06:00 AM pink_vampire: you are probably right.
06:00 AM pink_vampire: I know the gib is become thinner over time
06:01 AM pink_vampire: brand new it was nice and centered with the saddle, but now one side it almost 1 cm out
06:02 AM pink_vampire: Loetmichel: can you measure the backlash on the 6040?
06:02 AM XXCoder: now ill admit i dont ever do maintance, but isnt that wear little too fast?
06:04 AM pink_vampire: maybe..
06:20 AM Loetmichel: pink_vampire: no, i am not able to. its smaller than the 1/100mm indicator i got
06:21 AM Loetmichel: even on the machine thats six years old
06:23 AM pink_vampire: so you put your indicator, move toward the indicator abit, zero the indicator and the dro, then jog the machine super slow away from the indicator until you see some movement - is there a difference between the indicator and the dro?
06:23 AM Loetmichel: none
06:24 AM Tom_itx: morning
06:24 AM pink_vampire: mine is 0.2mm difference :(
06:24 AM pink_vampire: hi Tom_itx
06:24 AM XXCoder: hey
06:24 AM Loetmichel: and its usually done by moving away fast an then move back to zero, then moving in the other direction and move back to zero and look what the indicator says
06:28 AM pink_vampire: fast? not idea about that, the ways of the machine are super tight, so you need some force to move them, and the table very heavy to there is some inertia when it move fast
06:29 AM pink_vampire: Tom_itx: what ballscrew are you using on your machine?
06:29 AM JT-Cave: so much for milling boards this morning it's starting to rain
06:29 AM XXCoder: send some please heh
06:30 AM XXCoder: i miss days it rained here in summers
06:30 AM XXCoder: but its so rare nowdays
06:30 AM XXCoder: i used to bicycle oftem in warm rain
06:32 AM JT-Cave: been pretty dry here for the last few months after monsoon season was over
06:32 AM XXCoder: here it used to be 2 cold rain seasons and one warm rain season, and cold season which rarely snows
06:33 AM XXCoder: now its 2 mostly rainy cold seasons, hot summer and cold and sometimes rainy winter
06:36 AM Tom_itx: pink_vampire, https://www.ebay.com/itm/20mm-Linear-Guide-Rail-400-700-1000mm-RM1605-Ballscrew-Nut-BK-BF12-HGH20CA-Block/293069481061?hash=item443c4d6465:g:GawAAOSwYV5cLvEF
06:37 AM XXCoder: trusted store?
06:38 AM Tom_itx: that's just the generic set i got, dunno about the store
06:38 AM pink_vampire: single or Double nut?
06:39 AM Tom_itx: single iirc
06:39 AM Tom_itx is now known as Tom_L
06:43 AM XXCoder: tom how do you torque gibs properly?
06:43 AM XXCoder: im bit concerned she is tightening hers too much?
06:43 AM Tom_L: no gibs
06:43 AM XXCoder: drat need someone whop knows
06:43 AM Tom_L: there's a nut on the end of the shaft against the bearing
06:43 AM Tom_L: but that doesn't affect the screw nut
06:45 AM gregcnc: Part of this is working with equipment of unknown quality. Was the ballscrew properly made? What about the ways? How can you tell?
06:45 AM XXCoder: tom thats nice info!
06:56 AM Loetmichel: whats a gib?
06:57 AM Loetmichel: ah
06:57 AM Loetmichel: a "keil"
06:57 AM Loetmichel: the thing that eleminates play in dovetail linear ways
06:57 AM XXCoder: yeah
06:58 AM Loetmichel: arent those MEANT to wear?
06:59 AM Loetmichel: replacing them is a lot easier than replacing either part of the dovetail
06:59 AM XXCoder: yeah but 1 cm sounds like a LOT wear
06:59 AM XXCoder: but then i dont know enough
07:03 AM pink_vampire: XXCoder: it is go deeper 1cm..
07:03 AM pink_vampire: I think the ware is less then 0.1mm
07:03 AM XXCoder: what does you mean by "deeper"
07:03 AM alexfloca: hi guys, anyone present with deep knowledge of the pid algorithm used in linuxcnc?
07:04 AM gregcnc: taper is probably 1/50
07:05 AM pink_vampire: https://i.imgur.com/f2yCRQZ.png
07:05 AM pink_vampire: here you can see the gib
07:06 AM XXCoder: yeah ok i thought you meant it lost 1 cm thickness which is a big wear sorry :)
07:59 AM pink_vampire: LOL I think it's whole thickness it like 3-5mm
08:06 AM pink_vampire: the ballscrew is out!
08:09 AM pink_vampire: the inside part of the nut looking very clean
08:14 AM pink_vampire: I took all the balls out
08:15 AM SpeedEvil: Did you record the order in which they were packed?
08:15 AM gregcnc: lol
08:18 AM JavaBean: sad part is, speed is right. if you put the balls back in in the wrong order, it could wind up being worse than it was before dissassembly
08:19 AM gregcnc: If there are two sizes of balls.
08:19 AM pink_vampire: and there is some bright metal chips inside
08:20 AM skunkworks: wow - that does not look ground or scraped... That is a sliding surface.
08:20 AM JavaBean: lots of wear?
08:20 AM pink_vampire: lat me take some pics
08:21 AM skunkworks: like - mill cutting marks
08:21 AM pink_vampire: I think it is chips
08:22 AM JavaBean: chips and wear is what i am hoping. if raw milled then poor pink has bigger issues to deal with
08:22 AM pink_vampire: https://i.imgur.com/SRl5Vvc.png
08:25 AM gregcnc: I thought we had a look at the ways of this machine several years ago
08:26 AM gregcnc: how are chips getting into the ballscrew?
08:26 AM SpeedEvil: Chip fairys.
08:27 AM pink_vampire: https://i.imgur.com/5VM323H.png
08:27 AM pink_vampire: gregcnc: I think so
08:27 AM JavaBean: chips are the glitter of the cnc/milling world
08:28 AM pink_vampire: so what do you think about the ball nut?
08:28 AM gregcnc: you need to determine what wore
08:30 AM pink_vampire: I think the ball screw is not 100% straight
08:31 AM gregcnc: how was it lubricated?
08:41 AM roycroft: my mill table looked pretty glittery after i did some machining on brass yesterday
08:46 AM pink_vampire: gregcnc: lubricated? no idea, cutting oil?
09:35 AM perry_j1987: morning
09:37 AM pink_vampire: what do you think is better and stiffer design? https://i.imgur.com/vowIcku.png
09:51 AM gregcnc: back to back is stiffer
09:52 AM pink_vampire: what back?
09:54 AM gregcnc: A in your sketch. this stuff is in design handbooks. what will that be?
09:59 AM pink_vampire: I want to replace the single bearing with 2 angular contact bearings and preload them
10:08 AM gregcnc: in what?
10:12 AM robotustra: pink_vampire, I do variant A on my lathe
10:12 AM robotustra: because in this case you'll not need a spacer
10:13 AM robotustra: and preload nuts will stretch the spindle body
10:13 AM pink_vampire: to make a spacer is very easy
10:13 AM robotustra: but it's extra part
10:13 AM pink_vampire: what variant are you making?
10:14 AM robotustra: A
10:14 AM pink_vampire: it is extra part - true
10:14 AM robotustra: on your picture
10:15 AM robotustra: A and B are equivalent except for extra part
10:16 AM gregcnc: if you use precision bearings for universal mounting you don't need a spacer in either case
10:17 AM pink_vampire: not sure what do you mean by "bearings for universal mounting"
10:18 AM pink_vampire: robotustra: there is spacer in both of them
10:20 AM gregcnc: if standard bearings, do as you please. If you are using precision bearings, consult the engineering manual.
10:21 AM pink_vampire: I have 2 7201B bearings
10:24 AM robotustra: pink_vampire, what are you building?
10:24 AM pink_vampire: my poor Y axis
10:34 AM robotustra: for what device?
10:42 AM pjm: afternoon chaps, do you know of a low slop/backlash 'cable' control method to locate a position sensor away from an axis where space is really limited? I have a Y axis on my lathe but its really hard to squeeze a linear encoder in.
10:53 AM flyback: <veegee> JavaBean LTO (lithium titanate) is another really nice chemistry. Even lower energy density, but high power density and an order of magnitude higher cycle life. Also can fast charge at like 10C rates
10:53 AM flyback: what's the explosion rate
10:54 AM Loetmichel: probably like Lifepo4: zero
11:13 AM flyback: sounds good then
11:13 AM flyback: can't wait till my usb solar cells arrive this week
11:13 AM flyback: espically since I overpaid on ship $15
11:13 AM flyback: not happya boyut that
11:14 AM flyback: I didn't care because I was going to use a bunch of old gift cards but the site coudn't accept them
11:14 AM flyback: oh well
11:14 AM flyback: $30 for 3 still aint bad
11:15 AM flyback: z
11:15 AM flyback: G23962 - Our Most Powerful USB Solar Panel 5.5V, 1.2Amp, 6Watts (View Details)
11:15 AM flyback: G23942 - Deluxe 5.5V 0.560Amp USB Solar Panel (View Details)
11:15 AM flyback: G23903 - Deluxe 5.5V 0.360Amp USB Solar Panel (View Details)
11:15 AM flyback: fun for some projects
11:15 AM flyback: so a 2a usb battery would charge in 2 hrs on the first, 4 on the snd
11:16 AM flyback: waterproof to 3 feet
11:16 AM flyback: radio shack ripped me off for a 1/10 of that
11:17 AM flyback: a 6v2xxma cell and 6v84a cell $36
11:17 AM flyback: because I didn't notice the out o business discount wasn't taken off till I walked out the door
11:17 AM flyback: too late
11:22 AM Tom_L: getting closer on my gear macro: http://tom-itx.no-ip.biz:81/~webpage/rue/gear_macro.jpg
11:24 AM robotustra: how do you generate tooth surface?
11:24 AM Tom_L: generate a polyline in a loop
11:25 AM robotustra: I mean do you interpolate evolvent?
11:26 AM Tom_itx: LINE_PROF[XE=(((#R*COS(#A))-(#S*COS(#COUNTER)))+#CENTER_X), YE=(((#R*SIN(#A))+(#S*SIN(#COUNTER)))+#CENTER_Y), ZE=0]
11:33 AM flyback: too bad that doesnt work irl
11:33 AM * flyback lost all his top teeth to gum disease\
11:35 AM Loetmichel: re at home. MAN sometimes i wonder how those kids get their degrees these days. Just drove one of our temp workers home. He has a Bachelor of Mechanical engineering and is close to get his Master. so we were driving and he says: "Is that all this BMW can do? sounds rather meek."
11:37 AM Rab: The youth are accustomed to more exciting sound: https://en.wikipedia.org/wiki/Soundaktor
11:38 AM Loetmichel: i told him "Pretty much, yes, unless i drive with more RPM. Its just a 318i.", then at the next traffic light i accelerated with revving each gear up to 6000RPM instead of just 2500RPM... $me: "better?" Him: "HOW?" $me *facepalm*
11:40 AM Loetmichel: Rab: i tend to avoid revving it that high exactly BECAUSE its sounding like a "big one". rear muffler is rusted thru
11:41 AM Loetmichel: my point was that he didnt knew why that engine makes a lot more power at 6000 rpm than 2500 rpm.
11:41 AM SpeedEvil: With great power comes great torque * angular velocity.
11:43 AM flyback: and canadians
11:43 AM robotustra: what about canadians?
11:43 AM flyback: <SpeedEvil> With great power comes great torque * angular velocity.
11:43 AM flyback: <flyback> and canadians
11:44 AM robotustra: I'm not true canadian, that's why I probably didn't got the joke
11:45 AM Loetmichel: SpeedEvil: indeed
11:45 AM robotustra: ordered R8 collets for my new mill on wheels
11:46 AM robotustra: should be delivered soon
11:46 AM flyback: bbl
11:46 AM robotustra: got a milling machine now have to setup proper environment for it...
11:47 AM robotustra: and it could cost about the same as a mill itself :)
11:56 AM pink_vampire: mill on wheels O_o
11:57 AM robotustra: yep
11:58 AM robotustra: https://i.imgur.com/7LSaxWy.jpg on casters
11:59 AM robotustra: heavy duty casters
11:59 AM robotustra: Tom_L, I mean do you use the theory for the tooth profile in your macro like this: http://www-mdp.eng.cam.ac.uk/web/library/enginfo/textbooks_dvd_only/DAN/gears/generation/generation.html
12:01 PM robotustra: or you do just a circular approximation?
12:06 PM robotustra: or like this: http://www.engineeringexpert.net/Engineering-Expert-Witness-Blog/http://www.engineeringexpert.net/web/Engineering-Expert-Witness-Blog/wp-content/uploads//2014/01/gear_still3.jpg
12:07 PM robotustra: http://www.engineeringexpert.net/Engineering-Expert-Witness-Blog/tag/tooth-profile
12:40 PM Tom_L: it should be a correct profile
12:41 PM Tom_L: an arc like a 'string around the circle' thing
12:41 PM Tom_L: that's what involute is
12:43 PM gregcnc: does that generate gcode?
12:43 PM Tom_L: it should once i put a cutter to it
12:43 PM gregcnc: how is is cut?
12:43 PM Tom_L: i'd need to add some cutter relief at the bottom
12:44 PM Tom_L: gregcnc, it's more for theory than practicality
12:44 PM Loetmichel: Tom_L: involute gears?
12:44 PM Tom_L: if i was gonna cut some gears i'd use a gear cutter set or a hob
12:44 PM Tom_L: i just had the macro but it wasn't working right
12:44 PM Loetmichel: its more like: "how to get a non moving point of contact with two different diameter gears"
12:45 PM Tom_L: point of contact should be at 20 deg
12:45 PM Tom_L: in this case
12:45 PM Tom_L: it will select between 14.5 and 45
12:45 PM * Loetmichel is used to milling gears out of flat stock with a 2flute "finger" mill bit
12:46 PM Loetmichel: and yes. 20° is standard for involute gears
12:46 PM Loetmichel: i meant: the form is what it is so that the point of contact always stays on the same spot of the gear tooth, minimizing friction losses
12:46 PM Tom_L: this needs a bit more relief at the root
12:46 PM Tom_L: right
12:47 PM Loetmichel: it dosent "glide" of the other gear, it "rolls"
12:47 PM Tom_L: you mean like glxgears? :)
12:47 PM Loetmichel: right, using a mill bit requires modifying the root to accomodate for the mill bit radius
12:48 PM gregcnc: the theory of gears is pretty well determined. Making good gears is tough.
12:48 PM Tom_L: yeah
12:49 PM robotustra: ordered a replacement metal gear for my mill - just in case :)
12:49 PM Tom_L: i don't think i'd use this to cut gears unless they were wood
12:50 PM robotustra: https://www.aliexpress.com/item/32630042899.html
12:50 PM Tom_L: but having it can help in design
12:51 PM robotustra: to design a gearboxes?
12:51 PM Tom_L: i've seen several variants on profile but the main involute is the same as it should be on all of them
12:51 PM Tom_L: more relief in the pocket etc
12:51 PM Tom_L: rounded tips
12:52 PM Tom_L: those areas in theory should be non contact anyway
12:53 PM Tom_L: i think a spiral involute would be a hard one to draw
12:54 PM Loetmichel: Tom_L: geargenerator is surprisingly precise
12:54 PM Loetmichel: i made some alu gears with it and had them run for a few days with some load.
12:55 PM Loetmichel: single shiny line across each tooth at ~20°
12:55 PM Loetmichel: no visible error
12:56 PM Loetmichel: https://woodgears.ca/gear_cutting/template.html <- that one
12:56 PM Tom_L: 20 makes a stronger tooth 14.5 increases the load capacity. it's a tradeoff
12:56 PM Tom_L: Loetmichel, i've seen that one
12:56 PM FinboySlick: Loetmichel: you're cheating though. Everything is more precise in germany.
12:56 PM Loetmichel: point was: if it would be off it would have "smeared" the wear around the tooth
12:56 PM Loetmichel: not a single point
12:58 PM Loetmichel: FinboySlick: you think?
12:58 PM FinboySlick: Well known fact.
12:58 PM Loetmichel: FinboySlick: http://www.cyrom.org/palbum/main.php?g2_itemId=11702
12:58 PM Loetmichel: http://www.cyrom.org/palbum/main.php?g2_itemId=11711
12:58 PM FinboySlick: Look at Stefan. Even your tall people are more precise.
12:58 PM Loetmichel: http://www.cyrom.org/palbum/main.php?g2_itemId=11705
12:58 PM Loetmichel: http://www.cyrom.org/palbum/main.php?g2_itemId=11714
12:59 PM Loetmichel: :-)
12:59 PM Loetmichel: took me three tries to get it backlash-free though
12:59 PM Loetmichel: first try was rattling, second wouldnt fit, third was perfect ;)
12:59 PM Tom_L: funny, the 3d guys at the votech printed that last one as one piece in titanium
01:00 PM Loetmichel: tall people?
01:01 PM Loetmichel: stefan is not as tall as i am iirc. and i am just 180cm (5'11)
01:01 PM Loetmichel: 5'11"
01:01 PM Loetmichel: Tom_L: what last one?
01:02 PM Tom_L: looking for it..
01:04 PM FinboySlick: Loetmichel: he's 6'7"
01:05 PM Tom_L: i can't fine em right now
01:05 PM Tom_L: too much crap on the server
01:06 PM FinboySlick: As unofficial president of the Gotteswinter fanclub, I feel ashamed that I had to look it up. I will do better, I promise.
01:07 PM robotustra: you are talking about youtube celebrities from germany talking in english?
01:08 PM robotustra: big guy making small parts?
01:08 PM FinboySlick: I wonder if he'd agree with the word 'celebrity' but yeah.
01:09 PM FinboySlick: Though, it's not so much about Stefan as me picking on Loetmichel's german nature.
01:10 PM Loetmichel: FinboySlick: no way
01:10 PM Loetmichel: i met him once.
01:10 PM robotustra: there are "machinist" celebrities on youtube: like Stephen, Tom Lipton, Robin Renzetty,
01:10 PM Loetmichel: i am sure he was a bit lower than me
01:11 PM FinboySlick: Loetmichel: We call that the Chihuahua complex.
01:11 PM Loetmichel: seen syyl?
01:11 PM Loetmichel: hmm
01:11 PM Loetmichel: where is he when you need him?
01:11 PM FinboySlick: Loetmichel: He doesn't bother with short people like you...
01:11 PM robotustra: ha ha
01:11 PM robotustra: lol
01:12 PM Loetmichel: i really doubt it
01:12 PM robotustra: That little Tony
01:12 PM robotustra: AvE
01:13 PM robotustra: but Ave is not so good in machining I think :)
01:13 PM robotustra: because he is canadian
01:13 PM FinboySlick: robotustra: I know. I'm just amused by the word 'celebrity'.
01:13 PM Loetmichel: To be honest: i was more a fan of ChuckE2009s approach before he "woke" and lost it completely
01:13 PM FinboySlick: And it's 'This Old Tony'
01:14 PM Loetmichel: approach to machining i mean
01:14 PM FinboySlick: robotustra: AvE is not a machinist, he is a poet.
01:16 PM robotustra: Ave is inventing cool words
01:17 PM Loetmichel: FinboySlick: i stand corrected, someone on the german CNC channel said Stefan is 19Xcm... so about 15cm taller than me.
01:17 PM Loetmichel: interesting. i could have sworn i looked down at him
01:17 PM Loetmichel: may have been the ground
01:17 PM robotustra: It was John from NYC CNC
01:17 PM FinboySlick: Loetmichel: That or the chihuahua complex ;)
01:18 PM robotustra: He made a tour in the workshop of Stefan
01:18 PM robotustra: There is another guy from germany where John from NYC CNC made a tour
01:19 PM Loetmichel: FinboySlick: as i am of slightly above average height for my age i doubt its a complex. more likely i stood higher than him when i have met him.
01:19 PM gregcnc: "for my age"....
01:19 PM FinboySlick: Loetmichel: Yes, but my way is more amusing.
01:19 PM robotustra: https://www.youtube.com/watch?v=In6VqiHL7rM
01:20 PM robotustra: this one
01:48 PM JT-Cave: it's a hot sob outside today
01:48 PM JT-Cave: HI 103°F
01:48 PM Tom_L: agreed
01:48 PM Tom_L: humid anyway
01:49 PM Tom_L: was cutting some small tree branches
01:49 PM JT-Cave: only 58% here but damn hot
01:53 PM * JT-Cave has 92 spears to weld onto 3/4" square tubing...
02:21 PM Rab: JT-Cave, punji trap?
02:50 PM JT-Shop: fence
02:56 PM * JT-Shop noticed the jig had moved after about 30... what a PIA
05:07 PM robotustra: why people so devoided from the filings of beauty? grizzly mill is already long, but adding of power feeds of cnc conversion on it makes it even bigger and uglier
05:07 PM robotustra: power feed I think adds more 8-10"
05:09 PM robotustra: if to put stepper in front of the mill - this errected motor will eat the space of your room even worse
05:20 PM robotustra: I think I'll make cnc conversion my way
05:26 PM Tom_L: how's that?
05:28 PM robotustra: I'll try to put motors as compact as possible
05:28 PM robotustra: to not increase dimensions of the mill
05:47 PM JT-Cave: got a bit of rain and it cooled down a bit
05:48 PM roycroft: i need some 12mm stainless steel rod - about 500mm of it
05:49 PM roycroft: does anyone know of a good source in the usa?
05:49 PM roycroft: i figure since folks use it for linear motion rails people here would use it
05:49 PM JT-Cave: hardened rod?
05:50 PM roycroft: no, it doesn't need to be hardedn
05:50 PM roycroft: hardened
05:50 PM roycroft: nor even precision ground
05:50 PM roycroft: cold roll quality would be fine
05:50 PM JT-Cave: mcmaster or one of the online steel places
05:50 PM roycroft: online metals only sell it in 72" lengths
05:50 PM roycroft: i didn't think of checking at mcmaster though
05:51 PM JT-Cave: mcmaster should have shorter stock
05:51 PM roycroft: they do have a little of everything, it seems
05:51 PM roycroft: i find it on ebay really cheap
05:51 PM JT-Cave: yep
05:51 PM roycroft: but it comes from cyprus or slovenia
05:51 PM roycroft: and who knows when it will ever arrive
05:51 PM roycroft: i'm not in a hurry
05:51 PM Tom_L: JT-Cave, looks like it might rain here too
05:51 PM roycroft: but i would rather not wait until literally christmas to take delivery
05:52 PM JT-Cave: went from 92°F to 79°F in a few minutes
05:52 PM roycroft: yeah, it's actually decently priced at mcmaster
05:52 PM roycroft: thanks
05:52 PM roycroft: too bad i just ordered from them
05:52 PM roycroft: $24.50 for 18" of cold worked 304 rod
05:55 PM Tom_L: JT-Cave, you should have ordered that a little sooner
05:55 PM JT-Cave: maybe I should have shot magic crystals into the clouds with my cannon
05:55 PM roycroft: i could turn down some 1/2" that i have in stock, but with my lathe i'd have a hard time getting a good finish on it
05:56 PM Tom_L: heh anything's worth a shot when it's 100+ out
05:56 PM JT-Cave: turning 1/2" rod not on a swiss is futile if it has any length
06:04 PM roycroft: the problem is i don't have a follow rest for it
06:04 PM roycroft: well, i do, but it was made for a different lathe and i hae to modify it before i can useit
06:05 PM roycroft: with that length the rod will start oscillating as soon as i start cutting it
07:21 PM ziper: why did my cheap titanium drillbit fail on a stainless that my cheap black oxide one did quite well one?
07:21 PM ziper: a differing scale of cheapness?