#garfield Logs

Jun 22 2025

02:05 AM rifraf: hola como estas
05:02 AM Tom_L: muey bien
05:02 AM rifraf: how was your weekend, mine was perfect, ready for another weeks work, started with successful aluminium casting friday night and just got better
05:05 AM rifraf: i wonder why people don't use a kiln to melt aluminium, is so much better temp control, will wear out kiln trying to melt copper/brass/bronze though
05:06 AM rifraf: so got the cheapest electric furnace to do that for a start
05:06 AM Tom_L: maybe they don't have access to one
05:07 AM Tom_L: is electric cheaper for that than fuel?
05:07 AM rifraf: i think they may be it, would cost more than a cheap gas burner etc, but i didn't waste much money on the kiln, such a great deal now that i look at the commercial options
05:09 AM rifraf: i think so, was about $5 of elecrticity to do the first melt, but once up to temp looking at a dollar or so per melt i hope, and can get like 4 or 5 crucibles in the kiln for aluminium i reckon
05:10 AM rifraf: not even sure if its worth getting the kiln to use 21A again, the temp ramp at 10.8A seems perfect for resin burnout
05:13 AM rifraf: next project is the vacuum casting machine, some decent pipe offcuts, a few laser cut plates and some welding and will have one
05:14 AM rifraf: can use same vacuum pump i got for the vacuum chamber, need to make in inline cooler to chill the air somewhat before it goes into the pump
05:15 AM rifraf: Tom_L electric is only real option in the suburban area i live currently, neighbours would hate the noise and smell
05:18 AM rifraf: or else would get my old gear up here, i made a really nice waste oil furnace that also runs on gas or deisel, and combinations of waste oil and deisel were even better
05:18 AM rifraf: but noisy with air compressor running full time
05:19 AM rifraf: do you know what rue_mohr uses or fuel?
05:20 AM rifraf: for*
05:24 AM Tom_L: propane
05:26 AM rifraf: yep a fairly clean option, and not too costly if buying in bulk, bbq size not really cheap
05:27 AM rifraf: the oil/desiel will heat faster though, diesel still not cheapeven if you can get free waste oil
05:28 AM rifraf: did he ever say how much a melt costs?
07:34 AM aandrew: rue_shop2> the bipolar transistors have a current limit, based on their drive current, and thats super important for switching
07:34 AM aandrew: ahhh yes, that is important
10:20 AM rue_mohr: you can solely rely on the inductor saturation for the switching, but its less efficient