#linuxcnc-devel Logs

Nov 23 2020

#linuxcnc-devel Calendar

06:54 AM dgarr: jepler: thanks for isolating the includes problem, clang scan-build working now
02:26 PM -!- #linuxcnc-devel mode set to +v by ChanServ
04:11 PM cradek: andypugh: was it you who had that amazing table of like every screw thread ever made?
04:12 PM andypugh: Not _quite_ every one.
04:12 PM cradek: also, hi!
04:12 PM andypugh: http://www.bodgesoc.org/thread_dia_pitch.html
04:13 PM andypugh: While you are there, do you recall why we stopped allowing comments on the ends of lines in the INI?
04:14 PM cradek: Cool, you do have Waltham #17
04:14 PM cradek: I can't decide if this pitch is 0.125mm or 200tpi. it's encouraging that you have one and not the other.
04:15 PM cradek: I don't remember deciding to make that change...
04:16 PM Tom_L: i can't remember being able to do that
04:16 PM cradek: if so, it's surely because something had trouble reading that. those inifiles are parsed in C and bash and python and probably other languages I forgot too
04:16 PM andypugh: I wasn’t thinking that you made the change, but might perhaps remember why it was done (and maybe by who)
04:17 PM andypugh: I thought about twopass, but the only commits I found were specifically to handle trailing comments.
04:18 PM Tom_L: cradek, i found this: https://www.sizes.com/tools/thread_waltham.htm
04:19 PM cradek: I *think* that's what these screws are, but they're on an Illinois, not a Waltham
04:22 PM Tom_L: do you make them yourself?
04:27 PM andypugh: Too fine to be Progress?
04:27 PM cradek: I try not to, but I may have to make a batch of these. I have two watches on my bench with these screws stripped (3 each watch). They are obviously a weak spot. I'm searching extensively for factory parts first though.
04:28 PM Tom_L: http://www.ofrei.com/page1305.html
04:28 PM Tom_L: ran across that
04:28 PM Tom_L: rather proud of their stuff
04:29 PM cradek: andypugh: my best measurements are thread outside diameter 0.665 pitch .126
04:30 PM andypugh: Well, that’s a bit fat for a Wlatham.
04:30 PM cradek: Tom_L: the actual part is Illinois screw #1760
04:31 PM cradek: or was it 655
04:31 PM cradek: lemme measure again
04:31 PM andypugh: (according to my table, and the table list nominal rather than actual diameter. ie it neglects thread rounding or flatting. Which is an error that one day I might correct)
04:32 PM cradek: yeah .655
04:32 PM andypugh: This table agrees https://www.sizes.com/tools/thread_waltham.htm
04:32 PM cradek: I have one (out of six) screw with a few good threads still up near the head
04:32 PM andypugh: It’s very rare for a screw to be _over_ nominal
04:33 PM Tom_L: seems they're still in business or someone using their name
04:34 PM cradek: well I guess it may be one you don't have, like I said it's an Illinois part
04:35 PM cradek: but if I make them I'll do 200tpi instead of 0.125mm
04:36 PM Tom_L: https://pocketwatchdatabase.com/guide/company/illinois/catalogs/illinois-watch-company-supplement-catalog-1936/2
04:36 PM Tom_L: may be of interest...
04:36 PM cradek: Tom_L: all those old names are zombies that have been bought and sold a zillion times
04:36 PM Tom_L: i figured
04:39 PM cradek: Tom_L: I wish one of those books would show the sizes/specs of the screws
04:42 PM Tom_L: http://illinoiswatchcompany.com/
04:42 PM Tom_L: ask em?
04:44 PM andypugh: hmm, .65 v .655 is 256 thou v 258 thou so it isn’t a rounding from mm to inches.
04:44 PM andypugh: I mean 25.6 v 25.8
04:46 PM Tom_L: https://www.jewelerssupplies.com/horological/illinois_pocket_watch_parts.html
04:46 PM Tom_L: you probably are familiar with all these sites anyway...
04:47 PM cradek: holy crap, https://timeguy.com/Screenshot_2020-11-23%20Illinois%20Watch%20Company%201923%20Material%20Catalog%20PWDB%20Digital%20Archive.png
04:48 PM cradek: so it's actually .0260-200
04:49 PM cradek: I think I just made work for andypugh :-)
04:51 PM cradek: the corresponding tap is .0268 I guess
04:52 PM cradek: tap drill .022
04:52 PM andypugh: Cheaper than the other site :-)
04:54 PM cradek: andypugh: in case you want to add them, the source is page 68-69 of https://pocketwatchdatabase.com/guide/company/illinois/catalogs/illinois-watch-co-material-catalog-1923/76
04:55 PM andypugh: In 1923 the US inch was 25.4000508mm
04:56 PM andypugh: Probbaly not enough difference to account for the discrepancy
04:56 PM cradek: that's both funny and annoying
05:04 PM cradek: gosh I wish I could order parts at these prices ... or any price
05:04 PM rs[m]: why didn't they define the inch as 25.6mm when they had the chance...
05:04 PM cradek: 10
05:04 PM Tom_L: that jeweler's supply seems to have alot of screws
05:05 PM Tom_L: i used to get 'floor sweepings' for other applications in a box and found not much useful
05:06 PM cradek: yeah, I have some, but not the Illinois-specific assortment unfortunately.
05:07 PM cradek: they are sometimes handy. I have started with a screw from there, and changed length, cut or refinished the head to match what I want, etc
05:07 PM cradek: but in the assortments I have there seem to be no 200tpi screws
05:07 PM cradek: well of that diameter anyway
05:10 PM andypugh: Maybe you could thread-mill a die block :-)
05:11 PM Tom_L: smallest threadmill i see is 72-80 tpi
05:11 PM Tom_L: #0
05:12 PM andypugh: Well, oc course, cradek would need to hand-grind his own.
05:12 PM Tom_L: hah
05:12 PM cradek: I'd singlepoint them, I've never made dies, why bother?
05:13 PM andypugh: To make it more of an adventure.
05:14 PM cradek: filing the slots and finishing the heads would be more work than getting the threads right
05:14 PM andypugh: (I wonder how many lathes have 200 tpi on the chart?)
05:14 PM cradek: well it's called .005 feed
05:14 PM Tom_L: on the other end, my friend has gears for 3 tpi
05:14 PM Tom_L: he'd never used em until i knocked on his door
05:15 PM cradek: ha 3tpi!
05:15 PM andypugh: Not an issue with CNC, of course
05:15 PM cradek: yeah, yay for cnc
05:16 PM Tom_L: cradek, you won't need a microscope to see this http://tom-itx.no-ip.biz:81/~webpage/temp/thread1.jpg
05:16 PM cradek: what's the squares?
05:17 PM Tom_L: cutting mat
05:17 PM cradek: I mean the scale
05:17 PM Tom_L: 2"?
05:18 PM cradek: weird to see such a good thread and such a bad finish on the OD
05:18 PM cradek: that's bigger than the whole watch :-)
05:20 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/temp/thread.jpg
05:20 PM Tom_L: to replace that
05:20 PM Tom_L: i had to drill that out (glued in)
05:20 PM Tom_L: came to Ks in a covered wagon
05:21 PM cradek: what is it?
05:21 PM Tom_L: huge leg on an old square grand
05:22 PM cradek: cool!
05:22 PM Tom_L: rosewood
05:22 PM cradek: we all fix the craziest stuff
05:22 PM Tom_L: yup
05:23 PM Tom_L: the problem was when it was tight it had do be in a specific position
05:23 PM Tom_L: so i did the aluminum and put a 1/2" setscrew in from the backside so it was adjustable
05:24 PM cradek: bbl, cheers everyone, stay safe
05:24 PM Tom_L: later