#garfield Logs

Feb 23 2024

06:03 PM rue_mohr: obfuscated_d,
06:16 PM rue_mohr: did you see the almost complete update?
06:21 PM rifraf: any foam cutting experience?
06:21 PM rue_mohr: yea, I made a hot wire thing
06:21 PM rue_mohr: and lots on the cnc
06:22 PM rifraf: cool, i need clean cut black soft foam
06:22 PM rue_mohr: no
06:23 PM rue_mohr: well, a spikeball of some sort may work
06:23 PM rifraf: with nice finish, was gonna make a 2d profile from wire and make a attachement for cnc
06:23 PM rue_mohr: not a knife edge cutter tho
06:23 PM rifraf: yeah they look messy
06:23 PM rifraf: https://www.aliexpress.com/item/4001129075322.html
06:23 PM Tom_L: electric kitchen knife
06:24 PM rifraf: something like that hacked
06:24 PM rue_mohr: oh, not on cnc?
06:24 PM rifraf: yes, put that ont a cnc
06:24 PM rifraf: i need 2.5D profiles
06:24 PM rue_mohr: laser
06:25 PM rue_mohr: w/ airjet, maybe
06:25 PM Tom_L: fumes
06:25 PM rifraf: yep only have small laser but can attach maybe
06:25 PM rue_mohr: fan
06:25 PM rue_mohr: hmm, fumes IN foam, ick
06:25 PM rifraf: all methods seem to have fumes, but operation should be quiet so can open door and windoes of shed
06:26 PM rifraf: just imagining a quick clean slice, controlled so will not sit a burn in 1 spot
06:27 PM rifraf: rue so you made hotwire cnc?
06:28 PM rifraf: i wanna see what the cuts look like, how clean, does the foam get a bad smell?
06:28 PM rifraf: gonna get a cheap one and try, maybe not so cheap though
08:15 PM rue_mohr: rifraf, not a hotwire cnc
08:15 PM rue_mohr: hand horwire
08:16 PM rue_mohr: but, with a non-burnable template and a hand hotwire you can go pretty quick
08:16 PM rue_mohr: I wonder how a hotwire cnc could work for material support
08:34 PM rif_shed: the idea has potential for some designs
08:36 PM rif_shed: anyways seem simple enough to make a cnc hot wire cutter, order what looks like 1/2 decent one
08:37 PM rif_shed: they have these metal probe looking cutters, would be a thin tube with some nichrome wire inside am guessing
08:38 PM rif_shed: so need to make a thin tube bender and customise one
08:40 PM rif_shed: https://www.aliexpress.com/item/1005003662748310.html
08:41 PM rif_shed:
08:44 PM rif_shed: *9
08:45 PM rif_shed: hrm, keyboard and lathe not cooperating
08:46 PM rif_shed: maybe your wire bender can bend to a profile?
09:06 PM Tom_L: what profile?
09:07 PM Tom_L: that wire wouldn't work so good for a foam cutter, you need nichrome wire for that
09:09 PM rif_shed: pretty sure it has 5m of nichrome in that set, how stiff it is not sure
09:09 PM rif_shed: top you think that tool will not work?
09:09 PM rif_shed: Tom_L sorry
09:10 PM Tom_L: i dunno what shape you're cutting but it should cut foam ok
09:10 PM rif_shed: keyboard on knees while useing lathe, screen above lathe
09:10 PM Tom_L: we did model plane wings with nichrome wire with 2 patterns, one on each end
09:10 PM rif_shed: the profile would be a spinning top side on
09:11 PM rif_shed: think packaging
09:11 PM Tom_L: for the tops you're making?
09:11 PM rif_shed: yeah
09:11 PM Tom_L: that was kinda cool btw
09:11 PM Tom_L: did you wander thru my cnc build?
09:11 PM rif_shed: the standing top?
09:11 PM Tom_L: yeah
09:11 PM rif_shed: yes have got through a bit of it
09:12 PM Tom_L: i started one and decided it was a bad idea
09:12 PM Tom_L: so i started over
09:12 PM Tom_L: had it all modeled in cad first
09:12 PM rif_shed: yep the standing top blows people away, just makes no sense, i did find a few others on yourtube though
09:13 PM rif_shed: yeah mine is all modelled in cad, but nothing like finding the issues real world
09:13 PM Tom_L: i made mods along the way
09:13 PM Tom_L: mostly to suit the scrap i was able to find
09:14 PM rif_shed: am machining a bar of 80mm aluminium at momewnt to replace a part on tailstock
09:14 PM rif_shed: want more travel
09:14 PM Tom_L: i know about that
09:14 PM Tom_L: my Z is too short
09:14 PM Tom_L: get a vise & any length of tool and you're out of travel
09:15 PM rif_shed: yeah i made my Z 50mm more than i wanted, and for a 2.2kw spindle, only a toy on it now
09:15 PM rif_shed: 800w#
09:15 PM rif_shed: the extra 50mm was all needed
09:16 PM rif_shed: Tom_L have you made lots of cool parts on the new cnc?
09:17 PM Tom_L: a few
09:17 PM Tom_L: i did a couple molds for rue
09:17 PM Tom_L: for alum and plastic
09:17 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Assembly/Final/Z-Riser_blocks.jpg
09:17 PM Tom_L: i added those to get a little more Z
09:19 PM rif_shed: yep cool, on mine i made 3 diffferent Y gantry mounting heights, will be able to machine around 40mm thick plates
09:19 PM rif_shed: but this machine is primarily for the A axis, so built around that but keep milling in mind
09:19 PM Tom_L: did some alum parts for his sprayers
09:20 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A9_New/MODS/A12_slot_fit.jpg
09:20 PM Tom_L: and a tab bender for those
09:21 PM rif_shed: nice
09:21 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A9_New/MODS/fixture/A9_Fixture17.jpg
09:22 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A9_New/MODS/fixture/A9_Fixture7.jpg
09:22 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A9_New/MODS/fixture/A9_Fixture9.jpg
09:23 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A9_New/MODS/fixture/A9_Fixture10.jpg
09:23 PM Tom_L: that was a first try, i made a better one after that
09:23 PM Tom_L: did some single point threading
09:24 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Brass_cup/Brass_Cups2.jpg
09:24 PM Tom_L: just a random thread size
09:25 PM rif_shed: cool, my favorite random thread is M9 x 0.75
09:26 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/thread_mills/Thread_mill2.jpg
09:26 PM Tom_L: can cut just about any thread with that set
09:26 PM rif_shed: threadmilling is something i want to try
09:27 PM Tom_L: i wrote a macro for my cad cam to generate them
09:27 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/cutters/Keyseat_cutter1.jpg
09:27 PM rif_shed: yep all my tapping needs are done in spreadsheets
09:28 PM Tom_L: got that to cut some slots in a part for rue
09:28 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A12_New/A12_batch2.jpg
09:29 PM rue_mohr: rif, styrofoam or cushin foam???
09:29 PM rif_shed: cushion
09:29 PM rue_mohr: from what you siad I got cushin foam
09:29 PM rue_mohr: obfuscated_d, hello?
09:30 PM rue_mohr: yea ok
09:30 PM rif_shed: opencell sponge type packing foam
09:30 PM rue_mohr: yea
09:30 PM rue_mohr: does it cut with heat ok?
09:31 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A12_New/A12_P2_2.jpg
09:31 PM Tom_L: fixture for those latches
09:33 PM rif_shed: rue_mohr dunno, thats why i am asking
09:33 PM rue_mohr: all my stuff was styrofoam
09:33 PM Tom_L: i'm not sure that would wire cut as well
09:33 PM rif_shed: found a cnc foam place that have bags of offcuts i hope, will have to test i guess
09:34 PM rif_shed: maybe i need to make a high powered fast one?
09:34 PM Tom_L: make some small square boxes and mill the profile out of them :)
09:34 PM rif_shed: thats the idea Tom_L
09:34 PM Tom_L: wood
09:34 PM rue_mohr: I wonder if a long thin abrasive whip would do it
09:34 PM rif_shed: excepr cylinders, not square
09:35 PM rif_shed: oh, nope, need a quick fast solution, the tops take long enough
09:35 PM Tom_L: you could stand them up and do like a counterbore in the foam
09:35 PM Tom_L: instead of the side profile
09:36 PM Tom_L: might be easier
09:37 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Cube/Cube1.jpg
09:37 PM rif_shed: i wanna put a sheet of foam on mill, cut 10 sideways profiles with hot cutter, the cut 10 cyliders with a straight foam cutter
09:37 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Cube/Cube_small2.jpg
09:38 PM rue_mohr: fow do you support the foam and the other side of the cutter wire tho
09:38 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Cube/Turners_cube3.jpg
09:38 PM Tom_L: those were fun too
09:38 PM rif_shed: hold a block, that supports it for the profiles, then once a cylinder is cut it needs no more support
09:39 PM Tom_L: that's actually a lathe exercise i did on the mill
09:39 PM rif_shed: Tom_L i like it, i will do that classic one day soon, the machine is nearly tuned
09:40 PM rif_shed: rue_mohr not using the cutter wire, or hoping not to
09:40 PM Tom_L: was a project my kid started at votech and didn't have time to finish
09:40 PM Tom_L: so i programmed them and ran em
09:41 PM rif_shed: rue look at the stick bits, you think they work ok? i want to bend them to the profile i need
09:41 PM rue_mohr: not sure for that
09:41 PM rif_shed: https://www.aliexpress.com/item/1005003662748310.html
09:41 PM Tom_L: they may be too stiff
09:42 PM rif_shed: but they sell bent ones, so am sure i can form them
09:42 PM Tom_L: kinda looks like maybe just the tip gets hot but i can't really tell
09:42 PM rif_shed: hope not
09:43 PM rif_shed: was hoping you may have used em
09:43 PM Tom_L: put some #14 copper wire in an old weller gun and ben that to suit
09:43 PM rif_shed: yeah yeah, but meesier
09:43 PM Tom_L: rue would attack that idea :)
09:44 PM rue_mohr: well
09:44 PM rue_mohr: I use 12
09:45 PM rue_mohr: but more to the point, whats the melting point??
09:45 PM rif_shed: dunno yet
09:45 PM rue_mohr: well
09:45 PM rif_shed: must be less than 300°C
09:45 PM rue_mohr: same as a spong really, right?
09:45 PM rif_shed: yep
09:45 PM rif_shed: try with a sponge
09:45 PM rue_mohr: ok, well
09:45 PM rue_mohr: I have nichrome wire
09:46 PM rif_shed: ibut a bit lighter than sponge
09:46 PM Tom_L: Polyurethane foam product is a polymeric material consisting of repeating units of carbon, hydrogen, oxygen and nitrogen. Vapor Pressure N/A Melting Point 300-400°F
09:46 PM rue_mohr: I presume you dont
09:46 PM rue_mohr: hmm yea
09:46 PM Tom_L: fast way would be to make a positive of the shape you want and put celophane around it then use spray foam in a box
09:47 PM Tom_L: make the positive from teflon
09:47 PM rif_shed: spray foam is pretty messy in my experience
09:47 PM rue_mohr: I'll go try to cut a sponge in half with nichrome wire
09:48 PM rif_shed: i need to slice up some foam
09:48 PM rue_mohr: but its going on my twitter feed.
09:48 PM Tom_L: there goes rue's easy chair
09:49 PM rif_shed: good rue_mohr , X away, i have never tried it
09:49 PM rif_shed: X or twitter that is
09:50 PM rif_shed: i was impressed how fast they could cut a foam matress when i got one fitted to the back of my car
09:50 PM rif_shed: so it can be done easy
09:51 PM rif_shed: but they used a hot wire with long arms i think
09:51 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Can_Holder/A3/Mold_Rev2/Final_mold4.jpg
09:51 PM Tom_L: steel mold for his triggers
09:51 PM rue_shop3: wtf am I supposed to do after everyone faccated irc anyhoo
09:51 PM rue_shop3: arg, nobody alive int eh world
09:52 PM rif_shed: yep the apocolipse, thought would never see you guys again when there was just a few odd bods on freenode
09:53 PM Tom_L: that happened quick
09:53 PM rue_mohr: im suprised you could get in, they had it locked right out
09:54 PM Tom_L: mention libera there and you were banned
09:55 PM rif_shed: wow funny times
09:55 PM rue_mohr: so, if hot wire works, should I do a cnc jig for it?
09:55 PM rif_shed: yep
09:56 PM rif_shed: make a shaped wire and see if it holds its shape
09:56 PM Tom_L: if the ends are supported it might
09:56 PM rif_shed: we used to have nicrome in all sizes when i made heating elements
09:56 PM rue_mohr: when did you make heating elements?
09:56 PM Tom_L: my local electronics guy used to have a whole shelf full but he went out of business
09:57 PM rif_shed: rue_mohr a few years back
09:57 PM Tom_L: wire and ribbon
09:57 PM rif_shed: i was in the office though, not on the floor
09:57 PM rif_shed: got to go to france, that was a nice, then left
10:00 PM rue_shop3: 0.4mm
10:01 PM rif_shed: yeah might work, it springy but still deforms when bent right?
10:03 PM rue_shop3: doubled up ends...
10:03 PM rif_shed: the thinner the better i think as long as it holds a shape
10:03 PM rue_shop3: 7A
10:04 PM rif_shed: i hope it stays pretty clean and does not biuld up melted foam
10:04 PM rif_shed: would be great it is kinda rubbed off and cleaned itself if you get the speeds right
10:06 PM rue_shop3: huh
10:07 PM Tom_L: hot and fast
10:11 PM rue_mohr: https://twitter.com/RueNahcMohr/status/1761241804702171418
10:11 PM rue_mohr: :P
10:12 PM rif_shed: ok that is an awesome start
10:13 PM rif_shed: soft wire when red hot?
10:13 PM rue_mohr: yup, firenoodle
10:13 PM rif_shed: you should not need red hot or evcen glowing
10:13 PM rue_mohr: well, lets play
10:13 PM rif_shed: try 4A
10:13 PM rue_mohr: back in like 2 hours
10:14 PM rif_shed: k
10:29 PM rue_shop3: anyone ever bolted down a sponge before?
10:29 PM Tom_L: freeze
10:30 PM Tom_L: wonder how a wet sponge would cut
10:31 PM Tom_L: may not burn as much
10:31 PM Tom_L: may not cut either :)
10:32 PM Tom_L: trap it in a box
10:32 PM rue_shop3: oh, thats probably the best idea there
10:33 PM Tom_L: double sided tape on the bottom if necessary
10:35 PM rif_shed: velcro?
10:35 PM Tom_L: may not be porous enough
10:36 PM Tom_L: velcro works by snagging loops in the opposing side
10:36 PM rif_shed: sandpaper?
10:52 PM rue_shop3: wow, with all the carbon driven out its brittle as hell
10:52 PM rue_shop3: or in
10:54 PM rif_shed: the nichrome?
10:57 PM rue_shop3: yup
10:59 PM rif_shed: must be too hot
10:59 PM rif_shed: should heat for years
11:11 PM rue_mohr: uploading
11:13 PM rue_mohr: https://twitter.com/RueNahcMohr/status/1761257730826752476
11:15 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1300811.jpg
11:15 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1300812.jpg
11:16 PM rue_mohr: rif_shed, ok, so?
11:18 PM rif_shed: awesome, now do y and z at same time, make a 2.5d profile
11:19 PM rue_mohr: its GRBL
11:19 PM rue_mohr: I can just do anything
11:19 PM rue_mohr: ...
11:20 PM rif_shed: you can, its amazing rue
11:20 PM rue_mohr: like my fancy commercial cnc?
11:20 PM rif_shed: can you code arcs?
11:20 PM rif_shed: indeed, i am just gonna try the same
11:20 PM rue_mohr: I'm a bit ashamed I didn't build it, but its solid and nice
11:20 PM rue_mohr: yes, it does arcs just fine
11:21 PM rif_shed: can you keep the foam from going brown?
11:21 PM rue_mohr: I think it could be cut cooler
11:21 PM rue_mohr: I had it a lot cooler on the cnc run and the cut was a lot cleaner
11:23 PM rif_shed: for sure, and then easier to tweak with known speeds
11:23 PM rue_mohr: that was 200mm/min
11:24 PM rif_shed: you have any lighter foam from some packaging?
11:25 PM rif_shed: would maye be perfect at that speed
11:25 PM rue_shop1: G01 Z-11 F200
11:25 PM rue_shop1: G01 X23
11:25 PM rue_shop1: G01 Z0
11:25 PM rue_shop1: G00 X0
11:25 PM rue_shop1: rif_shed, I'll leave it to you
11:25 PM rue_shop1: that nichrome is from an old hair dryer
11:26 PM rue_shop1: hair dryers and toasters have lots
11:27 PM rif_shed: lol, cool, if you buy new it will have ohms per meter so you can calc the current a bit better
11:28 PM rue_shop1: I just dial it till it works
11:28 PM rif_shed: yep
11:29 PM rif_shed: need to see how the one ended heaters work
11:32 PM rue_mohr: do they say max temp?
11:36 PM rif_shed: 300°C
11:36 PM rue_mohr: hmm
11:37 PM rif_shed: not red at all i think
11:57 PM rifraf: https://wiretron.com/nichrome-resistance-informational-charts/