#garfield Logs

Jun 19 2025

04:05 AM rifraf: kiln sitting on 9A, i feel that the door is trying to do all the work now
05:02 AM rifraf: we got 200C, 45 ohm + 30 ohm in series, in paralel with a 30 ohm resistor, can get another 2 amps that way
05:03 AM rifraf: happy with me drawing 11A from a 10A socket? that supplied 20A happily yesterday?
05:19 AM rifraf: seems like temp holds well when it gets there, so not gonna be constant 11a, just to get to temp
06:50 AM rifraf: so far looks like the natural heating curve at 11A is gonna burn out resin perfectly, takes time to heat but this is the aim
06:50 AM rifraf: https://cdn.shopify.com/s/files/1/0255/7539/1341/files/Burning_Schedule_by_David_Collision_031ab361-d954-4834-ac5d-e65735ae3519.png?v=1741685075
06:51 AM rifraf: so can do without a cone controller i hope, pretty sure and extra hour or 2 at 730C shuld not be an issue
06:52 AM rifraf: then cast the metal in at around 500C
06:56 AM rifraf: what a win, so glad i didn't throw 1.2K on a aliexpress thing to heat a thimble
07:04 AM rifraf: oven slowly but surely cookin, https://desire3d.com/images/public/kiln/inside1.jpg https://desire3d.com/images/public/kiln/outside1.jpg
07:45 AM rue_mohr: you can load the breaker to 80% of its labeled rating
07:46 AM rue_mohr: didn't you say it was a 15A furnace?
07:47 AM rue_mohr: if so, should have a 20A breaker
07:48 AM rue_mohr: heh, even our clothes dryers here are 30A, and thats 240V
07:50 AM rifraf: no its watever i make it, current 11A
07:50 AM rifraf: on a 10A outlet 240V
07:51 AM rifraf: i know this would work better if i wired all coils in paralell, 21A
07:51 AM rifraf: current have 30 + 45 ohm in series, and that in parallell with a 30 ohm
07:52 AM rifraf: so 21 ohm resistance
07:52 AM rifraf: i currently making a standard resin print black
07:52 AM rifraf: not disappearing yet
07:53 AM rifraf: but am so happy
07:53 AM rifraf: all the wires on other side of socket cold, wires exposed so can watch the temps
07:54 AM rifraf: even the extension lead just warm from socket
07:55 AM rifraf: gonna get me brother to setup a 20Amp outlet for me, he is proper sparky so will do it right
07:56 AM rifraf: then can run optimally, for now this is safe for testing
07:59 AM rifraf: current temps on outside of oven https://desire3d.com/images/public/kiln/outside2.jpg
08:00 AM rifraf: current temps on inside of oven, https://desire3d.com/images/public/kiln/inside2.jpg
08:02 AM rifraf: mrxt week will print some castable resin and see if it disappears, the print still holding up so far, so resin way better at high temps than abs / pet etc
08:03 AM rifraf: but nice that outside no higher than 60C, safe
08:04 AM rifraf: this thermal can has come in very handy, have now got door not main heat, 2 walls inside are main element, roof and door and 1 wall are the ones in series
08:07 AM rifraf: would have taken me months to get an oven this good and safe it seems
08:07 AM rifraf: make*
08:07 AM rifraf: and so happy i understand the elements a bit already
08:08 AM rifraf: gonna be cool to see how hot it is still after 6 hours sleep, turned off obviously
08:18 AM rifraf: water washable resin print after 1 hour at 350C https://desire3d.com/images/public/kiln/resin-350C-1-hour.jpg
08:20 AM rue_mohr: hmm, you rewired it...
08:21 AM rifraf: many times
08:21 AM rue_mohr: it should be able to get to 1000c
08:21 AM rue_mohr: from what I saw of it
08:21 AM rifraf: is peak efficiency for 10A outlet now
08:21 AM rue_mohr: the element wire gets brittle after is heated, I dont recommend moving it at all after its used
08:22 AM rifraf: have it set to 730C at moment, max i need, but looks like it could take 6 hours to get there, will still work, this is the goal
08:22 AM rue_mohr: if the kiln has not been used in a long time, your also driving all the water out of it
08:22 AM rue_mohr: so after its deeply dry, it will heat up much faster
08:22 AM rifraf: https://cdn.shopify.com/s/files/1/0255/7539/1341/files/Burning_Schedule_by_David_Collision_031ab361-d954-4834-ac5d-e65735ae3519.png?v=1741685075
08:23 AM rifraf: gonna turn of at 350C, need sleep
08:23 AM rue_mohr: mhm
08:23 AM rifraf: will see what resin print like in the morning
08:24 AM rifraf: asked my boss if i can install at work, he ok with it, then can do 20 amp easy
08:24 AM rifraf: but no room at moment
08:24 AM rifraf: am sure my bro can wire me a 20A outlet, pretty sure the big aircons here would need that sort of current
08:25 AM rifraf: pretty cool oven though eh rue?
08:26 AM rifraf: haha 370C now and print has collapsed, starting to turn white in places
08:26 AM rifraf: this is not the castable resin, just standard stuff they say does not burn away cleaning, so no expectations of it disappearing
08:26 AM rue_mohr: ... the print could take 260c?
08:27 AM rifraf: the print stood up for an hour at 350C
08:27 AM rifraf: and i know its real temps, the thermal cam confirms what the temp guage says
08:27 AM rifraf: is gettin pretty hot when i open the door
08:28 AM rue_mohr: hmm, could make solderable parts...
08:28 AM rifraf: could do so many things
08:28 AM rifraf: i will get one more pic before i crash if you are here for a few min
08:29 AM rifraf: this was a clear resin print, went black after a few minutes but only just started collapsing
08:29 AM rifraf: will have a pot of aluminium in ther tomorrow
08:30 AM rifraf: we are still a bit away from that melting, need 650 or so
08:31 AM rue_mohr: late to leave for work, bye!
08:31 AM rifraf: cya on the flipside
09:08 AM rifraf: https://desire3d.com/images/public/kiln/outside-real.jpg
09:08 AM rifraf: https://desire3d.com/images/public/kiln/outside-thermal.jpg
09:09 AM rifraf: https://desire3d.com/images/public/kiln/inside-real.jpg
09:09 AM rifraf: https://desire3d.com/images/public/kiln/inside-thermal.jpg
09:10 AM rifraf: the resin print a bit closer up https://desire3d.com/images/public/kiln/resinprint-400C.jpg
04:21 PM rifraf: well done, https://desire3d.com/images/public/kiln/cookedresin.jpg
04:22 PM rifraf: lost 95% weight, would not want to be casting this stuff for sure
04:23 PM rifraf: and resin cooking is outdoor sport, sore blurry head this morn, tequila bottle still contains too much to blame it
04:27 PM aandrew: https://www.youtube.com/shorts/Gl0z5CYRMcc
04:27 PM rifraf: oven was still 305 C after 6.5 hours off, was 418C at midnight when turned off, dropping about 17 degrees an hour, kinda happy with that, opened to take print out but will see how it is after work
04:27 PM aandrew: that's pretty cool. I've seen the "use an LED as a photodiode" before but this looks like next level
04:29 PM rifraf: is interesting, my russian is lapsing so cannot understand :(
04:32 PM aandrew: hah even if it's lapsing I guarantee it's better than mine
04:36 PM rifraf: going to see my favorite russian tomorrow, not sure if right thing, guess time will tell
04:37 PM rifraf: but sunday big machine show with grandson, thats gonna blow him away, just loves earthmoving machines
04:39 PM aandrew: tht sounds awesome, I remember doing that with my boys when they were little
04:39 PM aandrew: that stuff just never gets old
04:40 PM rifraf: yep, kinda thing he will remember for ever, hope he can sit on one, he told me he is going to start up the excavator :)
04:52 PM rifraf: made index in case anyone wants to look at kiln project thus far https://desire3d.com/images/public/kiln/index.html
11:29 PM rue_mohr: ah!