#garfield Logs

Aug 11 2019

01:22 AM rue_mohr: yup
01:27 AM zhanx: why
01:27 AM rue_mohr: something strange about this electric guitar I got at a garage sale
01:27 AM zhanx: asking due to lack of knowledge
02:01 AM rue_mohr: something about the kid selling it and the guitar
02:01 AM rue_mohr: like what are the odds I would happen to have the EXACT knob it was missing in the parts collection for the electric guitar I was going to make?
02:10 AM rue_mohr: it needed a damn #3-48 screw
02:10 AM rue_mohr: I have two, and two #4-48 screws, apparently
02:10 AM zhanx: never answered my ?
02:10 AM rue_mohr: neither were long enough individually, ;)
02:10 AM rue_mohr: hhah playing with guitar too long, ready to do my welding, but now its raining
02:26 AM rue_mohr: I need a solution for moving around storage containers of greensand
02:36 AM zhanx: re-purpose the lawn mower
02:36 AM rue_mohr: good idea with a flaw
02:36 AM rue_mohr: all the shot lawn mowers have shot decks
02:36 AM rue_mohr: hmm I had a long day and cant think
02:36 AM rue_mohr: its raining so I cant do the welding I wanted to
02:43 AM rue_mohr: .. its 10mm mercury 0.2psi?
02:44 AM rue_mohr: huh
02:44 AM rue_mohr: seems so
06:04 AM Tom_L: flat bottom is a bad idea
06:04 AM Tom_L: unless you have a death wish
11:22 AM Tom_L: thickness causes differential rate of expansion at the joint
11:22 AM Tom_L: causing rue_mohr possible bloodloss
11:56 AM rue_bed: its thick tho
11:57 AM rue_bed: I"ll pretest carefully
11:57 AM rue_bed: dont know how much vacuum I need to pull tho
11:57 AM rue_bed: I think just 10mm mercury
11:57 AM rue_bed: which is like .2 psi
11:59 AM rue_bed: ah this one says 29 inches
12:00 PM rue_bed: which is full 14 psi
12:12 PM Tom_L: what's this for?
12:13 PM Tom_L: how much vacuum is in a TV tube? those are thick glass
12:35 PM rue_mohr: its for sucking bubbles out of fluids
12:35 PM rue_mohr: and sucking metal into lost wax castings
05:52 PM zhanx: rue_mohr, that setup dry as a bone already and I poured more water on it to keep it from cracking
06:17 PM Tom_L: you're not in NY anymore :)
06:18 PM Tom_L: 93 here atm
06:34 PM zhanx: 103 here
07:52 PM rue_mohr: it was rainign today
07:54 PM rue_mohr: http://ruemohr.org/~ircjunk/projects/vacuumplate/
07:54 PM rue_mohr: best just hit backwards in the slideshow
07:54 PM rue_mohr: I thoguht of a problem
07:54 PM rue_mohr: I have nowhere to put this vacuum table
07:55 PM rue_mohr: :/
07:55 PM rue_mohr: and I still have to make space for the cnc
07:55 PM rue_mohr: :///
07:55 PM Tom_L: casting looks good
08:20 PM rue_mohr: yea!
09:03 PM zhanx: rue_mohr, I so want to fire this forge up :(
09:43 PM Tom_L: so what you waiting for?
09:44 PM zhanx: the cement to cure?
09:45 PM rue_shop1: yea, the majorityof the water to settle out too
09:45 PM Tom_L: but he's in 1000F texax!
09:46 PM zhanx: true
09:47 PM Tom_L: another 525600 have passed by tomorrow
09:50 PM rue_shop1: ?
09:50 PM rue_shop1: well, the jars I got for the vacuum chamber didn't implode
09:50 PM Tom_L: yet
09:50 PM rue_shop1: from what I can tell they aren't even close
09:51 PM Tom_L: how did you seal them?
09:51 PM rue_shop1: the pump can pull 20inches of mercury
09:51 PM rue_shop1: and the rubber seal I did was leaking a bit
09:51 PM zhanx: lube it
09:51 PM rue_shop1: I might top coat the plate with silicone
09:51 PM zhanx: no use vasoline
09:51 PM rue_shop1: but I'm basically there
09:51 PM rue_shop1: :)
09:52 PM Tom_L: is this thing big enough to evacuate air from the things you need evacuated?
09:53 PM Tom_L: next you need an autoclave
09:53 PM rue_shop1: it fits the thing I have for doing lost wax casting
09:53 PM Tom_L: k
09:53 PM rue_shop1: I have a small electric furnace
09:54 PM Tom_L: they have a big autoclave at the school
09:54 PM Tom_L: for doing carbon fiber etc
09:55 PM rue_shop1: hmm yep
10:02 PM rue_mohr: I suppose I can just do a test with some lead/tin/zinc
10:04 PM zhanx: true
10:05 PM rue_mohr: I still have to bolt down the pump and cough up a better seal, but those are just improvements
10:12 PM zhanx: pics?
10:15 PM rue_mohr: huh, can you do a youtube video?
10:16 PM zhanx: not yet
10:16 PM rue_mohr: hmm
10:16 PM rue_mohr: did you see th ones on the site?
10:16 PM zhanx: just want to see the jar on the vacuum plate
10:17 PM rue_mohr: oh I do have an udpate
10:17 PM rue_mohr: hold on
10:19 PM zhanx: one of the ranch cats has adopted me i think
10:22 PM rue_mohr: http://ruemohr.org/~ircjunk/projects/vacuumplate/slide.htm
10:22 PM rue_mohr: 3d printed silicone mold for casting the investment for lost wax casting
10:22 PM rue_mohr: (heh)
10:22 PM zhanx: so a large piece of rubber
10:22 PM rue_mohr: er, the plate yea
10:22 PM rue_mohr: oh drat I
10:22 PM zhanx: rechuck it
10:23 PM rue_mohr: http://ruemohr.org/~ircjunk/projects/vacuumplate/p1130294.jpg
10:23 PM rue_mohr: sorry I boof pasting uls with the slideshow
10:23 PM rue_mohr: ^^ 3d printed silicone mold for casting the investment for lost wax casting
10:23 PM zhanx: cut a grove in the face for that so you get a better seal
10:23 PM rue_mohr: http://ruemohr.org/~ircjunk/projects/vacuumplate/p1130296.jpg
10:23 PM zhanx: i saw the rest of it
10:23 PM zhanx: I just jumped to the last one
10:23 PM rue_mohr: it fits like that on pipe, you weld the wax thing to it
10:23 PM rue_mohr: yea no, these ones inserted
10:24 PM rue_mohr: cause I backtracked a bit
10:24 PM zhanx: k
10:24 PM rue_mohr: but yea, the plate seal is a chunk of innertube
10:24 PM zhanx: looks good over all
10:25 PM Tom_L: yup
10:25 PM Tom_L: i should send you some neoprene sheet
10:25 PM zhanx: you just need a vacuum lube
10:25 PM rue_mohr: yea, I'm kinda impressed at my ability to throw togethor tools :)
10:25 PM rue_mohr: I'm thinking a scrape coating of silicone on the plate
10:25 PM rue_mohr: or even just a thin layer
10:25 PM rue_mohr: its softer
10:26 PM rue_mohr: I dont know how long that pump will last
10:26 PM rue_mohr: the thing I got it from had an output filter
10:26 PM rue_mohr: and it had a LOT of stuff come out of it...
10:26 PM zhanx: yea i made the mistake of googling diy lube
10:26 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Assembly/Final/Way_Cover.jpg
10:27 PM rue_mohr: I give it some oil and it sounded better, It still draws 20inches vacuum
10:27 PM Tom_L: i got lots of that neoprene free
10:27 PM rue_mohr: zhanx, hahah
10:27 PM Tom_L: 1/16 & 1/8"
10:27 PM zhanx: 40 hours on the pump change the oil
10:27 PM rue_mohr: its a scroll pump
10:27 PM rue_mohr: from an air quality sampler
10:28 PM zhanx: 80 hours then
10:28 PM rue_mohr: the other options you might have seen there were a diaphram pump and a fridge compressor
10:28 PM rue_mohr: its got no oil thing zhanx ?
10:28 PM zhanx: you have to remember oil loves moisture
10:28 PM zhanx: it should
10:28 PM zhanx: its a scroll
10:28 PM rue_mohr: ...
10:29 PM rue_mohr: I'll look again later
10:29 PM zhanx: toss me a pic of the front of it
10:29 PM zhanx: its only like 1-2 oz
10:30 PM zhanx: so second question
10:30 PM zhanx: are you sealing the glass with a candle wax as you pull the vacuum?
10:32 PM Tom_L: the plate seal is a chunk of innertube
10:32 PM zhanx: yea but you can seal it better like that
10:32 PM Tom_L: <rue_mohr> I'm thinking a scrape coating of silicone on the plate
10:33 PM Tom_L: i'm wondering how porous his cast plate is
10:33 PM rue_mohr: nothing, I have images
10:33 PM rue_mohr: I think its supposed to be on a sippy-cup
10:34 PM rue_mohr: the vacuum process is just used a) to pull the air out of the investment b) to pull the metal into the mold
10:34 PM rue_mohr: I think its ok
10:35 PM rue_mohr: in the youtube videos, I only saw their stuff go to 10mm mercury
10:35 PM Tom_L: how do you get the hot metal into the mold under a vacuum?
10:35 PM zhanx: k, i thought it was to set the wax
10:36 PM zhanx: Tom_L, dump valves
10:36 PM rue_mohr: Tom_L, thats the neat bit, the investment is porous, you just sit it on there while you pour
10:36 PM rue_mohr: no lid
10:36 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1130326.jpg
10:36 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1130327.jpg
10:36 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1130328.jpg
10:36 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1130329.jpg
10:36 PM rue_mohr: the bolt ont eh top IS blind
10:37 PM rue_mohr: the "thing" is the output overpressure relief
10:37 PM zhanx: left hand bolt?
10:37 PM rue_mohr: nope normal, it held equipment on that I took off
10:37 PM rue_mohr: I double checked, its blind
10:38 PM zhanx: k. odd its a scroll. it needs some oil
10:38 PM rue_mohr: sippy-cup
10:38 PM zhanx: guess so
10:38 PM rue_mohr: and I'm confused, nonally does it not have anything as it was set up, but its output was FULL of bad black stuff
10:39 PM rue_mohr: aka "I'm eating myself"
10:39 PM Tom_L: i guess i'd have to see the process. i can't picture it
10:39 PM Tom_L: i get the concept
10:39 PM rue_mohr: Tom_L, youtube lost awx casting
10:39 PM zhanx: yea, maybe it had a oil mister that was left out
10:39 PM rue_mohr: almost everyone is doing the same thing
10:40 PM rue_mohr: zhanx, yea, they had filters going in and out of it
10:40 PM rue_mohr: or maybe is had oil-free parts inside?
10:40 PM zhanx: no not with a scroll, wrong type
10:40 PM rue_mohr: k
10:40 PM rue_mohr: I didn't want to open it up
10:40 PM zhanx: sometime soon add an inline oiler to it
10:40 PM rue_mohr: it still draws 20mm and I have other options if it dies
10:41 PM zhanx: yep
10:41 PM rue_mohr: my other options just aren't as good :)
10:41 PM zhanx: or just spray some oil before you use it
10:41 PM rue_mohr: yep, I have that vacuum break valve I can use
10:42 PM zhanx: also toss in some steel wool in that output port
10:43 PM Tom_L: not how 'how it's made' shows it
10:43 PM Tom_L: https://www.youtube.com/watch?v=Xeg575g_Cgs
10:43 PM zhanx: can't watch it Tom_L
10:44 PM Tom_L: i got no sound on this one either
10:44 PM rue_mohr: steel wool?
10:44 PM rue_mohr: its a peice of rag right now
10:44 PM zhanx: works as a mist arrestor that don't stop the air flow
10:44 PM zhanx: http://ruemohr.org/~ircjunk/tempimage/p1130328.jpg <- 3 red lines what is that bolt
10:44 PM rue_mohr: Tom_L, god thats huge
10:45 PM rue_mohr: 8-o
10:45 PM rue_mohr: omg
10:45 PM rue_mohr: oh yea...
10:45 PM rue_mohr: lovin this
10:46 PM Tom_L: i figured they would show the process real good
10:46 PM rue_mohr: oh crap, no backing material
10:48 PM rue_mohr: ok, THAT is cool, I'm gonna incorperate some of that
10:48 PM rue_mohr: movigng on
10:48 PM Tom_L: the video?
10:48 PM rue_mohr: let me find you a typical vid
10:48 PM Tom_L: i've seen that one before
10:48 PM Tom_L: but forgot about it
10:49 PM Tom_L: i hate the ones that drag it out with bs talking
10:50 PM Tom_L: if i can't get it in 30 sec i move on
10:50 PM rue_mohr: yea, I'm skipping past one
10:50 PM Tom_L: what was that coating they used in the pro one?
10:50 PM Tom_L: before the sand bath
10:51 PM Tom_L: that way you don't need a form, just the mold
10:51 PM Tom_L: but you gotta bake it
10:52 PM Tom_L: maybe that was a pottery clay slurry
10:52 PM Tom_L: then baked in a kiln
10:53 PM rue_mohr: https://www.youtube.com/watch?v=H4vSYcYwdNU
10:53 PM rue_mohr: this looks descent
10:54 PM rue_mohr: admittedly I skipped a lot
10:54 PM rue_mohr: but its all there
10:56 PM Tom_L: you got an oven to burn it out?
10:56 PM rue_mohr: yea I got a tiny little kiln
10:56 PM zhanx: I got a toaster oven!
10:56 PM Tom_L: good
10:56 PM rue_mohr: like 8" wide and 4" high
10:56 PM Tom_L: i got a toaster oven
10:56 PM rue_mohr: must be for plates! :/
10:56 PM Tom_L: set up for reflow
10:57 PM zhanx: rue_mohr, we are gonna get Tom_L making stuff again
10:57 PM rue_mohr: heh
10:57 PM rue_mohr: I'm playing with designing stupid little things to keep my cnc machiens busy
10:57 PM Tom_L: i like the pro one better where they just bake the sand around the part
10:57 PM rue_mohr: yea, tahts really cool
10:57 PM Tom_L: instead of inside a box etc
10:57 PM rue_mohr: well, I need a way to do bigger things, so, yea
10:57 PM Tom_L: the process seems the same to me
10:58 PM Tom_L: and you use less material
10:58 PM rue_mohr: I'm really surprised they dont have to atealst back that casting with sand
10:58 PM rue_mohr: even loose sand
10:58 PM Tom_L: they used sand to coat it then baked it in place
10:58 PM rue_mohr: yea
10:58 PM Tom_L: i bet that slurry was pottery clay
10:58 PM rue_mohr: and they capture the wax too
10:59 PM Tom_L: while they're baking it yes
10:59 PM Tom_L: i think anyway. i'd have to re watch it
10:59 PM rue_mohr: I'll try plaster again, like to know if that can be made to work
10:59 PM Tom_L: gotta bake out the moisture if you do
11:02 PM Tom_L: so you need a wax printer now
11:03 PM rue_mohr: not quite yet
11:03 PM rue_mohr: I can just make a wax thing, try some plaster, and cast in zinc or soemthing
11:03 PM Tom_L: i wonder what kind of wax they use in the 'how it's made' one
11:03 PM rue_mohr: see if its going to generally behave
11:03 PM Tom_L: i bet it's similar to machinable wax
11:03 PM rue_mohr: I bet its just cheap
11:03 PM rue_mohr: maybe machinable
11:03 PM Tom_L: it's not pure parafin
11:04 PM Tom_L: but that company that makes machinable wax makes other types too
11:04 PM rue_mohr: I want to make 2 more of those plates this week
11:04 PM Tom_L: https://www.machinablewax.com/
11:05 PM rue_mohr: but I need to do up more greensand first
11:05 PM rue_mohr: yea, I made mine with parafin and LDPE
11:05 PM rue_mohr: in a pot, over the smelter, on low...
11:05 PM Tom_L: we manufacture 6 different formulations of wax that are specifically formulated for precision lost wax casting, prototyping and more.
11:06 PM rue_mohr: yup
11:06 PM Tom_L: i'm guessing less plastic in it over machinable wax
11:06 PM zhanx: why plastic and not cooling?
11:08 PM Tom_L: shore 30 compared to 55
11:08 PM Tom_L: for casting wax
11:08 PM Tom_L: over machinable wax
11:09 PM Tom_L: my bot wheels i made were shore 30 poly
11:10 PM rue_mohr: it would be nice to be able to just get stuff
11:10 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/sumo_files/mini_wheel1.jpg
11:10 PM Tom_L: i should have put it in a vacuum but i didn't
11:11 PM rue_mohr: what did you use for realease?
11:11 PM Tom_L: fiberglass mold release cause i had a gallon
11:11 PM Tom_L: from previous days
11:11 PM Tom_L: anything..
11:11 PM Tom_L: wax would do
11:11 PM rue_mohr: hmm
11:12 PM Tom_L: spray on the release
11:13 PM rue_mohr: this week I want to set up more of those silicone things, the release is cornstarch, I'm wondering if I can make a water mix and spray it on, then dry
11:13 PM Tom_L: don't see why not
11:14 PM Tom_L: unless the cornstarch changes when it gets wet
11:14 PM Tom_L: baby powder would work too probably
11:17 PM Tom_L: https://contenti.com/jewelry-casting-supplies
11:17 PM Tom_L: small scale
11:18 PM Tom_L: https://contenti.com/jewelry-casting-supplies/injection-wax/freeman-flake-injection-wax
11:19 PM Tom_L: ok i'm done clicking for the night.
11:20 PM zhanx: http://ruemohr.org/~ircjunk/tempimage/p1130328.jpg <- 3 red lines what is that bolt rue_mohr missed that
11:20 PM Tom_L: use chocolate instead of wax then you can eat it when you're done
11:22 PM Tom_L: gnite
11:22 PM zhanx: nite
11:25 PM rue_mohr: thats the blind one I was talking about
11:25 PM zhanx: its shaped tho
11:26 PM rue_mohr: its just a regular hex bolt...
11:26 PM zhanx: the shaft thing below it
11:26 PM rue_mohr: I super-checked it, its blind
11:27 PM zhanx: k
11:27 PM rue_mohr: I super-checked it cause of that neck below it :)
11:27 PM rue_mohr: there was a bit of dirt, so I had to dig around in the bottom to be sure
11:28 PM rue_mohr: they had a handle mounted via it
11:30 PM rue_mohr: hahah, that thing I made sells for $1000 usd
11:30 PM rue_mohr: hahahah
11:31 PM rue_mohr: the bell jars are $91, my thing was $0.50 CAD