#linuxcnc Logs

May 23 2023

12:51 AM Deejay: moin
02:10 AM Loetmichel: roycroft: i was thinking about using the "chimney effect" between the slabs to facilitate accelerated drying (water gets transported off faster if air movement is faster) Just wondering if that would mean that the slabs would warp more.
02:13 AM jpa-: the limit is probably moisture movement inside the wood, not moisture removal from the surface
02:14 AM XXCoder: I would say heating box wood is in and exchanging air slowly would have far greater effect
02:14 AM Loetmichel: I see
02:14 AM XXCoder: heat can be essentally free if you build it basically like glasshouse with column to rise heated air out with humidity?
02:15 AM XXCoder: but warping with any of those? completely no idea
02:26 AM -!- #linuxcnc mode set to +v by ChanServ
03:16 AM travis_farmer[m]: Morning ☕️
04:40 AM NoGodDamnIdea: hello everyone
04:42 AM Tom_L: Loetmichel, make a solar wood kiln
04:42 AM XXCoder: tom is that similiar to concept I outlined earlier?
04:42 AM Tom_L: https://owic.oregonstate.edu/solarkiln/plans.htm
04:43 AM Tom_L: morning
04:43 AM Tom_L: XXCoder, i dunno... i wasn't here earlier :)
04:43 AM XXCoder: oh sorta is I guess
04:43 AM XXCoder: I can envision some improvement
04:44 AM XXCoder: like piping air though thin slot sheet with black paint on it
04:44 AM XXCoder: then it enters the solar kiln thing in that link
04:44 AM JT-Cave: morning
04:45 AM Tom_L: damn. we should vote on something... we're all here
04:48 AM JT-Cave: lol
04:59 AM Loetmichel: Tom_L: i have neither a sawmill nor woods to get the treees from, I was just idly wondering what would happen.
05:02 AM XXCoder: i saw some video where guy buys cheap firewood and turns em into stuff after cutting em up and drying em
05:02 AM XXCoder: well it mostly didnt need all that much drying but yeah
05:44 AM JT-Cave: rooster just crowed
06:02 AM JT-Cave: my buddy built one of those solar kilns
06:02 AM XXCoder: how well did it work?
06:19 AM JT-Cave: don't know
07:09 AM NoGodDamnIdea: anyone here know how to cut foam in weird shapes?
07:11 AM Tom_L: hot wire
07:13 AM Tom_L: (nichrome wire)
07:14 AM JT-Shop: drunk monkey with a hot knife
07:15 AM travis_farmer[m]: lol
07:15 AM Loetmichel: NoGodDamnIdea: define "weired shapes". CNC router (MEGA mess of styro dust everywhere) or bent into shape hot wire.
07:15 AM Tom_L: https://hotwirefoamfactory.com/foam-cutting-tools/
07:15 AM Tom_L: foam cutting cnc
07:15 AM Tom_L: chew it
07:15 AM NoGodDamnIdea: https://www.audioreviews.org/yaxi-earpads-review/
07:15 AM NoGodDamnIdea: something like this
07:15 AM Tom_L: that would be weird
07:16 AM NoGodDamnIdea: I got a bunch of them from flea markets that I recondition and give out to friends
07:16 AM NoGodDamnIdea: (the headphones)
07:16 AM Loetmichel: ah, not styrofoam but actual soft foam
07:16 AM NoGodDamnIdea: and I would like to also make foam earpads like that one
07:16 AM NoGodDamnIdea: yep
07:17 AM * Loetmichel has done something similar on my CNC mill/router by soaking PU foam in water, freezing it into a block and then milling said block. Worked pretty well. You'll have to be fast though. :)
07:18 AM travis_farmer[m]: i was just going to mention that...
07:19 AM rmu: NoGodDamnIdea: all chemistries i know that produce soft foam are on the very toxic side. do not recommend.
07:20 AM Loetmichel: rmu: you mean the hot wire cutting?
07:20 AM rmu: no i mean the polyurethane resins producing foam "in place"
07:20 AM Tom_L: order replacements from the MFG
07:21 AM NoGodDamnIdea: hmm that one looks cut to me
07:21 AM NoGodDamnIdea: great ideal loetmichel but I think it would degrade the foam
07:21 AM NoGodDamnIdea: Loetmichel*
07:21 AM Loetmichel: the PU resins for soft foam (to pour into a mold) are actually pretty harmless ONCE hardened. Touching the uncured resin can give you a bad case of allergies though.
07:22 AM Loetmichel: NoGodDamnIdea: why would it degrade the foam?
07:22 AM CloudEvil: Mixing incorrectly can with some of them leave lunreacted product
07:22 AM Loetmichel: its waterproof AND cold resistant.
07:22 AM NoGodDamnIdea: if it was poured into a mold it would have a shiny finish, no?
07:22 AM Loetmichel: NoGodDamnIdea: yes, the mold usually produces closed cells at the skin.
07:22 AM rmu: once cured and mixed correctly, yes, it is harmless
07:23 AM NoGodDamnIdea: I imagine freezing it in solid ice wont do it good :/
07:23 AM NoGodDamnIdea: but I think these are cut somehow
07:23 AM rmu: you can't really hot wire cut PU foam
07:24 AM CloudEvil: You can if you use disposable employees.
07:24 AM Loetmichel: rmu: you can. its a mess though, both in smell and in leaving a sticky residue at the cut
07:24 AM rmu: those headphone foam cups are probably die-cut
07:24 AM Loetmichel: CloudEvil: good one. Can i steal that sometimes?
07:25 AM CloudEvil: I think various places got to that some centuries before
07:25 AM rmu: pu foam doesn't melt, it is a thermoset, so you would need to burn it.
07:25 AM CloudEvil: yes.
07:25 AM Loetmichel: rmu: yes. Thats why it stinks to high heaven and leaves a (decomposed) residue at the hot wire cut surface
07:27 AM Loetmichel: CloudEvil: i meant stealing that sentence. Not the action.
07:52 AM NoGodDamnIdea: rmu how can you die cut that foam at an angle?
08:06 AM rmu: something like this probably https://www.youtube.com/watch?v=Bw_waJCWTmQ
08:08 AM * CloudEvil wishes cryogenic freezers were cheaper.
08:08 AM rmu: doesn't show die cutting but it should give you some ideas ;)
08:24 AM mits5782[m]: Does anyone have estimates on jog and feed speeds to use for a machine? I am lost on orders of magnitude... is 100mm/min a normal speed, or is that a slow speed for feed limits?
08:24 AM mits5782[m]: should I be able to jog at 1000mm/min on an aluminium frame?
08:24 AM mits5782[m]: how do I know 😄
08:24 AM CloudEvil: Well, you could look up what other machine feed rates are.
08:25 AM mits5782[m]: I don't even know what other machines there are
08:25 AM CloudEvil: Feed rates in operation - what is the largest depth of cut you can take with your fastest rotating tool.
08:25 AM mits5782[m]: hah
08:25 AM ZincBoy[CAON][m]: 100mm/min is really, really slow. Look at speeds and feeds calculators. Like HSM works or Gwizard
08:26 AM CloudEvil: So if you have a 6000RPM spindle that has a bit that can take off .1mm per pass, you need 600mm/minute to max out that cutter
08:26 AM mits5782[m]: hsm is windows only I think? I'll see if gwizard is portable
08:26 AM CloudEvil: .1mm
08:27 AM CloudEvil: Rather also depends on your use-case.
08:27 AM ZincBoy[CAON][m]: I run 4000mm/min in steel with a high speed tool path and could go faster if needed. Rapids are 15000mm/min on my machine.
08:28 AM mits5782[m]: what size of cutters are you talking about?
08:28 AM ZincBoy[CAON][m]: 1/2", 1" DOC, 0.05" WOC, 6000rpm spindle.
08:28 AM CloudEvil: If you want this to be burning up carbide inserts at $1000/day because you need to push that fast, vs occasionally sharpened HSS cutters.
08:28 AM mits5782[m]: ok
08:29 AM mits5782[m]: so I need to scale back a bit because I'm doing 1/8" bits on down to like .2mm, but thanks for telling me how to calculate this quickly
08:32 AM ZincBoy[CAON][m]: With that size end mill you will be limited by your max spindle rpm. You really need to use one of the calculators. FSwizard.com is online.
08:32 AM mits5782[m]: oooh, thanks
08:32 AM ZincBoy[CAON][m]: Same as HSM advisor, just the online version.
08:35 AM mits5782[m]: hmm
08:36 AM mits5782[m]: https://www.linuxcnc.org/docs/html/config/ini-config.html#_display_section
08:36 AM mits5782[m]: MIN_VELOCITY
08:36 AM mits5782[m]: MIN_LINEAR_VELOCITY
08:36 AM mits5782[m]: is that a doc bug?
08:42 AM ZincBoy[CAON][m]: Kind of. Axis still uses the MIN_VELOCITY ini value if the MIN_LINEAR_VELOCITY is not specified. Nothing else uses MIN_VELOCITY though.
10:10 AM NoGodDamnIdea: looked at it rmu , still no ideas D:
10:20 AM Unterhaus__ is now known as Unterhausen
10:53 AM rmu: NoGodDamnIdea: do you have 5 axis water jet cutter?
10:54 AM Unterhausen: I don't think my spindle can go that fast
10:54 AM NoGodDamnIdea: I do not :(
10:54 AM Unterhausen: oops, responding to a message from hours ago
10:54 AM NoGodDamnIdea: but i cant wrap my head around how you can make it that shape
10:54 AM Unterhausen: I have some spindles off of a moore grinder that I wish I could get data on
10:59 AM rmu: NoGodDamnIdea: cut the inside with a disc, then punch/cut it out
11:02 AM NoGodDamnIdea: but it is not donut shaped, and its cut at an angle inside also :(
11:05 AM rmu: NoGodDamnIdea: form cutter
11:08 AM rmu: there are probably many methods how those pads can be manufactured. you can pull the foam over something formed like a "stopfpilz" (darning mushroom?) and cut the inside like that
11:08 AM rmu: etc...
11:11 AM NoGodDamnIdea: will have to investigate
01:16 PM Mukunda[m] is now known as Mukunda3342[m]
06:09 PM * JT-Shop calls it a night
07:46 PM -!- #linuxcnc mode set to +v by ChanServ
07:46 PM -!- #linuxcnc mode set to +v by ChanServ