Re Formbot Raptor Review (also why not a Chiron?)

First - good job and I really hope you did not pay for it.

If you are buying a big printer for printing bigish stuff I suggest the Chiron. We (FRC Team 1989) have 2 one at my house that gets most of the use and one at the school that is lesser used. Mine was bought in last August and has so far seen about 70kg of filament pass through it the one at school was in October and only has about 30kg under the belt. There where no failures so far at the school and 3 on mine One reason for that is that anything that went wrong on mine also was fixed at the school one as a preemptive thing except the nozzle thing (I destroyed a block by cross threading the nozzle when I changed it.

I want to state that the way we use the printer is probably non-standard from any other use. For starters we print items really using the whole volume, and then we print mechanical parts - so between the 2 machines we probably used a kg or 2 of PLA the rest was 95% HIPS 5% PETG. It comes with a V5 clone with the PTFE all the way to the nozzle so to be safe we replaced the stock ptfe with a capricorn high temp one and the one in my printer has been running with a nozzle temp at 255C 24/7 with no problems for the 70some KG of HIPS we ran through that thing. We print with a .8 nozzle at the school one and a .7 on mine (remember the cross thread event) The bed temp is constantly at 105 C for the HIPS and we got a plastic sheet draped over it to keep the ambient higher in the “chamber” which helps with printing the HIPS. We use prusa slicer print external perimeters at .88 internals at 1.2-1.5mm .36 layer height and the Max Vol E throttled at 16.5mm3/sec. Can’t say much about fan performance (some complain about the stock fan being weak) as on HIPS and PETG we print with the FAN off.

Now to the 2 fails. At about 30kg of filament we broke a wire for the hotend thermistor and it gave a Probe 0 unexpected error - so even if kinda funny wording it shut the printer down to prevent a thermal runaway. Under inspection it was found that the X harness is a bit too short and if you go the full width of the bed (all 400 mm) all the time -which we do then you put strain on it and bend it sharply. We replaced the wire and extended the harness about 3 in (7 cm) Just 2 days ago the same happened to the bed thermistor wire and we fixed and extended that harness too. Comparitavely speaking under the same use pattern on the Matterhackers pulse(Pruse i3 MK2 something clone) we had a serious breakdown once every 5-7 kg So this works much better

Now some prints
A twin double rack 20 gears and 2 double racks meshing to show accuracy in print

Looking at the start of this years robot about 4kg of HIPS in this pictrue.

Got way more. So if you want to get into something bigger I can recommend the CHIRON. About $500 (unless its on sale) There is some room for improvement - yeah putting a (super)volcano on it probably would be nice or going to marlin 2.0 would also be nice. But that is up to you. Out of the box it works fine and is usable and inexpensive. We were impressed of how much filament we can put through an inexpensive printer like that. The ultrabase works great (at least for HIPS, ABS and PETG) We had 3 failed prints so far (the 2 i indictated above when a wire broke) and one at school when a student decided to print a 15mm diameter spacer with a 1mm wall thickness and 360mm tall and printed it without a brim and it fell over when it got to about 300 mm I was surprised it stuck down that long. When the prints finish and the build plate cools to about 60 the HIPS (and ABS) just pops off and you start the next print