#linuxcnc Logs

Jun 03 2020

#linuxcnc Calendar

01:02 AM CaptHindsight: sliptonic: there wasn't some normalized machine unit, it uses what you configure it with and then scales based on metric or inch gcodes
02:01 AM Deejay: moin
05:20 AM JT-Cave: morning
05:22 AM XXCoder: yo
06:19 AM Tom_L: morning
06:19 AM XXCoder: yo
06:38 AM JT-Cave: ho
08:44 AM veek_ is now known as veek
09:34 AM sliptonic: In the 2.9 .ini configuration it allows for a UNITS=INCH. I assumed this would override the configuration units just for that joint. But that doesn't seem to be the case. Anyone know how it works?
10:40 AM Rab: https://books.google.com/books?id=yyUDAAAAMBAJ&pg=PA42#v=onepage&q&f=false
10:41 AM Rab: "New tool is both pliers and wrench"
10:42 AM Rab: Not all of the other innovations have stood the test of time.
10:42 AM jymmmm: Rab: 1935, damn
10:44 AM jymmmm: Rab Sure they have... just using water bottles instead of subs =)
11:15 AM FinboySlick: Rab: Wow. So much nostalgia.
11:15 AM FinboySlick: I love the advert section at the end.
11:50 AM roycroft: heh folks
11:51 AM roycroft: someone here was asking me a day or two ago why i would want to use abs for 3d prints instead of petg
11:51 AM roycroft: and i responded that petg is difficult to post process and cannot be glued, which are big reasons for using abs for some things
11:51 AM roycroft: but i'm thinking more about it, and the first parts that i need to print will be router jigs
11:51 AM roycroft: and a bearing will press on them with a fair amount of force
11:52 AM roycroft: is petg going to be able to take that kind of force without deflecting?
11:52 AM roycroft: abs is pretty darn rigid
12:20 PM CaptHindsight: roycroft: if you weren't printing it which plastic would you use?
12:21 PM roycroft: if i were using a subtractive process i'd probably make it out of wood or acrylic
12:21 PM roycroft: ideally i'd make it out of aluminium, but i don't have a cnc mill at this point
12:22 PM roycroft: the 3d printer is in part a stop gap until i finally get my cnc conversion done on the mill-drill
12:22 PM roycroft: and once that conversion is done the 3d printer would still complement the cnc mill-drill
12:23 PM roycroft: right now i'm just trying to figure out what's mostly likely to work best for me
12:23 PM roycroft: i had no budget for a 3d printer, and the money i've spent on the printer itself is a stretch
12:24 PM roycroft: i'll buy what i need to move forward, but i don't have cash for a lot of random experimenting
12:24 PM roycroft: i need my experiments to be well thought out and likely to succeed
12:26 PM CaptHindsight: http://www.matweb.com/search/DataSheet.aspx?MatGUID=3a8afcddac864d4b8f58d40570d2e5aa
12:26 PM CaptHindsight: http://www.matweb.com/search/DataSheet.aspx?MatGUID=a696bdcdff6f41dd98f8eec3599eaa20&ckck=1
12:28 PM roycroft: yeah, i know the basic specs of those materials
12:28 PM roycroft: i'm just looking for a real world perspective from someone who has made jigs like that out of petg
12:28 PM roycroft: it's softer/more pliable than abs
12:29 PM CaptHindsight: the problem with cnc glue gun filaments is that they don't have specs on the pellets they used to extrude the filament
12:29 PM roycroft: but is it good enough for that application?
12:29 PM roycroft: for that matter, is pla durable enough?
12:29 PM CaptHindsight: it will vary by supplier
12:29 PM roycroft: and since the printer will come with a partial spool of pla, i guess that should probably be my starting point
12:30 PM roycroft: i should be able to use petg on the machine i bought with no modifications
12:30 PM roycroft: if i want to use abs i'll probably need to get at least a glass plate
12:30 PM roycroft: and possibly build an enclosure around the machine
12:31 PM roycroft: a spool of abs will cost roughly the same as a spool of petg
12:31 PM roycroft: but with abs i'd need that glass base plate as well, so the question is my mind is: would petg likely suffice, or is it likely not going to work out?
12:31 PM roycroft: if the latter, then i'd get the glass base plate + spool of abs right way
12:32 PM roycroft: and not bother trying petg (for now)
12:32 PM roycroft: someting i'll need to decide, of course - i was only asking in case someone else has real world familiarity with both materials and a perspective to offer based on that
12:35 PM CaptHindsight: must be lots of filament remnants out there
12:42 PM CaptHindsight: roycroft: have you tried asking in #reprap
12:42 PM CaptHindsight: someone might ask you for a drawing or picture of what you want to print
12:43 PM roycroft: no, i was actually looking for some 3d channels, and for a channel for my printer manufacturer/model, and did not find any
12:43 PM roycroft: but i haven not tried other vendor channels
12:43 PM roycroft: this is cnc-related, but not really directly linuxc-cnc related
12:43 PM roycroft: unless i try to get linuxcnc to drive my printer :)
12:44 PM roycroft: so i figured it was not too far off topic to ask here
12:45 PM roycroft: but yeah, i might get better answers on a channel more devoted to additive cnc machining
12:45 PM jdh: is that what it is
02:02 PM CaptHindsight: acrylic sheet is fairly brittle, ABS and PETG are far less so
02:31 PM jymmmm: Unles you get into the 1" thick, then you can make your own whale and shark enclosure, and bullet proof case =)
02:33 PM jymmmm: Jsut keep acetone and MEK away from it =)
03:00 PM CaptHindsight: jymmmm: I use transparent aluminum for my shark tanks
03:01 PM jymmmm: CaptHindsight: I use stainless steel leader line =)
03:49 PM t4nk_freenode: heh
03:49 PM t4nk_freenode: I used to clean the exhaust of my bike with mek when I was a kid
03:56 PM andypugh: A 2-stroke presumably?
03:59 PM roycroft: mek is nasty stuff
03:59 PM roycroft: very useful
03:59 PM roycroft: but very nasty
04:06 PM andypugh: Wikipedia says that MEK is relatively safe. https://en.wikipedia.org/wiki/Butanone
04:08 PM roycroft: i think it says that it's not been tested very much
04:08 PM Rab: I tried to use it to derust the inside of a motorcycle tank, since it was rumored to be effective for that purpose. But it didn't seem to do anything.
04:08 PM roycroft: i have some
04:08 PM roycroft: and i use it
04:08 PM Rab: roycroft, what's your application?
04:08 PM roycroft: but i don't like being near the fumes
04:09 PM andypugh: I think that in this day and age, anything anyone was concerned about would be tested to death.
04:09 PM roycroft: i use it for cleaning and for gluing abs and polycarbonate
04:09 PM Rab: ahh
04:10 PM Deejay: gn8
04:11 PM t4nk_freenode: https://assets.catawiki.nl/assets/2016/10/20/c/8/e/c8e551f0-96ea-11e6-8b95-69fad659587e.jpg sth like that, but shifting with feet instead of hands
04:13 PM Rab: I've used this stuff to bond acrylic to polycarbonate, works great: https://www.chemical-concepts.com/scigrip-4.html
04:15 PM Rab: "Shelf Life: 2 years"...wonder how it degrades. The container seems airtight.
04:15 PM XXCoder: slightly unstable chemicals I guess
04:19 PM jymmmm: SHELF LIFE Two years in tightly sealed containers. The date code of manufacture is stamped on the bottom of the container. Stability of the product is limited by the evaporation of the solvent when the container is opened. Evaporation of solvent will cause the cement to thicken and reduce its effectiveness. Adding of thinners to change viscosity is not recommended and may significantly change the properties of the cement.
04:19 PM jymmmm: t4nk_freenode: MEK works too
04:20 PM jymmmm: t4nk_freenode: They talk about a "california version", lol, fucking Calif, no longer sells MEK in bulk
04:21 PM Rab: I believe that's this: https://www.scigripadhesives.com/scigrip-4sc-low-voc-acrylic-plastic-cement/
04:22 PM jymmmm: roycroft: white vinegar for removing rust works awesome
04:22 PM Rab: "
04:22 PM Rab: This product is currently available in Europe and Asia only.
04:22 PM Rab: But I believe it is available to California as well.
04:23 PM jymmmm: Rab Everything is illegal in Kommifornia now
04:24 PM jymmmm: Rab: I had a friend smuggle me in some MEK from across the border... state border that is =)
04:26 PM jymmmm: Rab: They tried to sell a replacement for MEK (and a dozen other solvents) for about two years. IT was so bad, they finnally pulled it off the shelfs
04:32 PM andypugh: For removing rust I like to use Molasses. Diluted 10:1 with water it works very gently over a period of weeks. Great for delicate sheet metal work, but also on anything where you have time, but absilutely do not want to damage it.
04:32 PM andypugh: and when you are finished, you have sugary water to dispose of.
04:43 PM Tom_L: nice sweet tea?
04:51 PM andypugh: Fortified with iron!
05:34 PM jymmmm: andypugh: Would have never thought of molases in a milllion years. And though vinerage works GREAT, just so suprised at well it works no matter how much rust there is.
05:36 PM andypugh: I think Mollasses was discovered by Aussie farmers. (it’s sometimes used to add to Silage as cow feed) So perhaps they ended up with puddles and noticed something interedting. It’s a “chelation” reaction if you are interested.
05:36 PM sync: all of the "safe" rust removers are just chelation agents
05:36 PM sync: some with some surfactants but it'll do without
05:37 PM andypugh: It’s cheap and low effort and easy to use in bathtub quantities for large parts. It just isn’t fast.
05:38 PM jymmmm: sync: I've never bought any "rust removers", just vinergar
05:39 PM sync: depending on what you want to do just vinegar is not as effective as it could be
05:39 PM jymmmm: andypugh: Yeah, the slow process can be great for restoration projects. Vinegar is like 8 to 36 hours depending on temperature
05:39 PM jymmmm: sync: It has been for me, anything else would be sand/bead blasting
05:41 PM sync: phosphoric acid is also great as it will passivate the steel
05:41 PM jymmmm: ?
05:41 PM sync: but chelation agents will only eat the rust
05:42 PM jymmmm: ah, vinergar is the closest acid I like to play with. I how a bottle of sulfuric acid around here somewhere, but that's for bad drain clogs
05:43 PM sync: phosphoric is handy to have around
05:43 PM jymmmm: such as?
05:44 PM jymmmm: It's thats whats used to etch PCBs?
05:44 PM sync: no
05:45 PM sync: you probably can use it tho
05:46 PM jymmmm: Eh, the most exotic thing I have is two cans of 1,1,1 =)
05:46 PM sync: it's absolutely not exotic
05:47 PM jymmmm: IT's internationally banned, I'd say that's exotic =)
05:48 PM sync: no, it's not really banned
05:48 PM sync: I have a drum of it somewhere
05:49 PM sync: tetra is banned iirc but you can still get it for research purposes
05:52 PM jymmmm: Trichlorotrifluoroethane
05:53 PM andypugh: There are very many 1,1,1 compounds.
05:53 PM jymmmm: ah, well that's the one I have =)
05:56 PM jymmmm: $4000 a bottle?! https://www.emdmillipore.com/US/en/product/112-Trichlorotrifluoroethane,EMD_CHEM-TX1167
05:58 PM andypugh: I would giess that that is 112, a different compound.
06:02 PM CaptHindsight: emdmillipore.com is how R&D for pharma gets into the gazillions of $$
06:03 PM CaptHindsight: you can get phosphoric acid at auto parts stores and home depot
06:03 PM CaptHindsight: it's usually labelled as rust remover
06:03 PM jymmmm: cleaning tiles iirc
06:05 PM jymmmm: This stuff works great, guess what it is??? https://www.amazon.com/Edfred-63817-Stall-Tile-Cleaner/dp/B000UDEBVQ
06:05 PM jymmmm: CaptHindsight: ^^^^^^^^^^^^^^^^^^
06:05 PM CaptHindsight: https://www.amazon.com/Gallon-Grade-Phosphoric-Remover-Clean/dp/B06XZSW3QX
06:07 PM CaptHindsight: jymmmm: phosphoric acid
06:07 PM CaptHindsight: Nonionic surfactant*
06:07 PM CaptHindsight: https://www.edfredcorp.com/SDS/EDFRED%20Shower%20Stall%20&%20Tile%20Cleaner%20SDS.pdf
06:08 PM jymmmm: ding ding ding, tell him what's he won Don Pardo... A BRAND NEW CAR!!!! <audiance applauses>
06:09 PM CaptHindsight: lots of cleaning chems are low cost way of getting things like acids that would cost you a ton in low volume
06:10 PM CaptHindsight: sometimes my drum price (per/kg) is higher that what it is as a consumer product
06:11 PM jymmmm: CaptHindsight: Need citric acid??? https://www.target.com/p/lemi-shine-dish-detergent-booster-24oz/-/A-49155581
06:11 PM jymmmm: CaptHindsight: SDS says "trade secret" =)
06:12 PM jymmmm: CaptHindsight: Yeah, HazMat fees probably
06:31 PM CaptHindsight: lots of consumer products have more cost tied up in packaging than the formulation inside
06:32 PM t4nk_freenode: that sure goes for the cat pee + vaseline I bought as flux from china.
06:36 PM jymmmm: t4nk_freenode: What makes you think it's non-human urine???
06:37 PM CaptHindsight: the taste of course!
06:37 PM t4nk_freenode: experience ;)
06:43 PM jymmmm: lol
06:44 PM jymmmm: I'm not liking sunbeam heated blankets/throws/etc, over the years they are having a bad reputation for just failing out of the blue when you need them the most.
06:49 PM roycroft: my timing gear appears to be repaired, but my welder did not like the job
06:49 PM roycroft: it spit and sputtered like crazy when he welded on it
06:49 PM roycroft: but it's straight and i don't even have to chase the inside threads
06:49 PM roycroft: and, most importantly, it is now one piece of metal again
06:50 PM roycroft: and it cost me a beer, which was acceptable :)
06:53 PM Tom_L: hope it was a choice beer
06:54 PM jymmmm: NearBeer? Generic white label beer?
06:55 PM jymmmm: What more do you need to know? https://thenewportblast.com/wp-content/uploads/2015/02/Generic-White-Beer-Can-e1423776833175.jpg
07:04 PM roycroft: it was a homebrew, of course
07:04 PM roycroft: and my welder makes brew systems for a living
07:05 PM roycroft: so he appreciated it
07:05 PM roycroft: especially since it was a good homebrew
07:05 PM roycroft: anyway, i just put the part on the lathe and cleaned up the weld with a file
07:06 PM roycroft: he recommended a file and not a lathe tool, because he feared that the lathe tool might crack the part due to the interruped cut and the crappy quality of the metal
07:06 PM roycroft: and the bearing slips over the shaft just fine, the bearing nut screws down fine, so i think i'm good to go
07:08 PM jymmmm: woohoo
07:09 PM roycroft: yes, that's a relief
07:09 PM roycroft: and i don't think there will be any more surprises, since the machine has been completely disassembled now
07:09 PM roycroft: i'll know in a week or two, when i'm done reassembling it
07:10 PM roycroft: and i had the brilliant thought today that when do reassemble it i might print some bearing shields with my new 3d printer to try to keep the dust out of them
07:10 PM roycroft: maybe that will keep them from getting gummed up right away with sawdust
07:12 PM * roycroft would almost call it a cunning plan, one of which no less than baldrick himself might be proud
07:12 PM roycroft: if only in involved a turnip
07:13 PM SpeedEvil: Modest filter, and a fan toblow clean air can help a lot
07:13 PM roycroft: it would be difficult to filter or to blow clean air around the bearings
07:14 PM roycroft: however, if i'm using proper dust extraction there shouldn't really be all that much sawdust down below the conveyor
07:14 PM roycroft: i suspect that the previous owner did not use extraction much, if at all
07:15 PM roycroft: he struck me as the kind of guy who would work in a room so full of sawdust it's hard to see, wearing no ppe
07:17 PM roycroft: http://machinerymax.com/Event/LotDetails/10999498/DELTA-31250-DRUM-SANDERSEE-NOTES
07:17 PM roycroft: that is the model sander i am working with
07:18 PM roycroft: the bearings in question are below the conveyor, clearly seen in the 3rd picture
07:19 PM SpeedEvil: ah
07:20 PM roycroft: it should be trivial to print a cap that fits over the bearings, though
07:20 PM roycroft: and that would probably keep 80% of whatever dust gets down there out of the bearings
08:54 PM veegee: Alright, found a good deal for six "70 pint" dehumidifiers
08:54 PM veegee: going to run them in parallel in my industrial unit. Hopefully that does something
08:54 PM veegee: Might be able to get away with a smaller AC
08:54 PM Tom_L: it will at least contribute to the electric bill
08:55 PM veegee: They are using about 600W each
08:55 PM veegee: electricity here is only $0.10/kWh on average
08:55 PM veegee: much cheaper in the night when I'm usually there
08:56 PM veegee: also can write it off in taxes
08:56 PM Tom_L: what'd you find out about the loading dock?
08:56 PM veegee: Didn't attempt to change that yet. Still unpacking and setting up machinery and so on
09:00 PM CaptHindsight: what does Canada require for work with freons?
09:01 PM veegee: CaptHindsight are you getting at a DIY system?
09:01 PM veegee: I'm not sure of the laws, but I saw an "AC refill kit" at the hardware store
09:09 PM CaptHindsight: veegee: you might be better off using one like this http://airconditionercanada.com/airconditioners/Haier-ESA424-Mid.html
09:10 PM veegee: yeah a few of those in parallel
09:10 PM veegee: but need the dehumidifier as well because the AC will just make it cooler but still humid
09:11 PM CaptHindsight: even one at 24K btu will likely add more comfort than 6 of those dehumidifiers
09:14 PM CaptHindsight: https://www.amazon.ca/dp/B00UV3LH4Y/ref=ca_xb_dp_go_web_gl_home
09:15 PM CaptHindsight: all you need is a vacuum pump and some hand tools, they come pre-charged
09:17 PM CaptHindsight: https://www.amazon.ca/OLMO-Alpic-Ductless-Split-Conditioner/dp/B07BGFJC2M/ref=sr_1_4?dchild=1&keywords=24000+BTU+Mini+Split+Air&qid=1591236484&sr=8-4
09:21 PM CaptHindsight: and a drill for wall anchors
09:47 PM jymmmm: DIY mini split... https://www.homedepot.com/p/MRCOOL-DIY-Gen-3-18-000-BTU-20-SEER-ENERGY-STAR-Ductless-Mini-Split-Air-Conditioner-Heat-Pump-w-25-ft-Install-Kit-230-Volt-DIY18-HP-230B25/311900321
09:48 PM jymmmm: no purging required as both the unit and split are precharged
10:04 PM CaptHindsight: lower cost to buy a different unit and a vacuum pump