As a little commentary for the above pictures........
This is a second UP! Mini printer that I recently acquired for £107 as "parts or not working"
The seller knew nothing about 3D printers and could not test it or provide much detail on its condition.
From what I could establish it was a customer return but it sounded like the extruder was as new and unused.
The unit arrived yesterday. It is not new but is in very nice condition. It was originally supplied by Amazon and was returned to them for reasons unknown. It then went into an auction of some sort as it has an Auction company label and lot number on it.
From papers that I found in the bottom of the box, under the packaging, it is obvious to me that this was used by a student for a project. I may be being very unfair but I have a suspicion that this printer was bought to complete a students project and then returned on some pretext. Somewhat like people buying suits and digital cameras for weddings and then returning them afterwards.
The good news for me is that I got a very nice condition UP! Mini for a bargain price.
I decided to strip it down for a clean and inspection. I also want to reverse engineer parts of the controller board to better understand the design and potentially change the build plate heater temperature control design. I thought other forum members might also like to see some more in depth views of the units interior.
Having done some investigation I know that this unit was built after December 2014, is fitted with a Version 3 Extruder, and was supplied by Amazon on 17 June 2015. It was returned to Amazon and then auctioned by SimonCharles Auctioniers.
The pictures of the controller board show it to be well made but not perfect by any means. The twisted pair of heat sinks are caused by the heat sink fixing pin hole being incorrectly positioned. The soldering quality looks fine so it should be reliable on that front. Bear in mind that this board lives inside a heated chamber caused by the build plate heater running at 60 Degrees C. Small heat sinks are present on the three servo driver IC's and (extruder?) Power MOSFETS. The power supply switching IC,s are heats inked through the PCB which isn't to my liking. The components all appear to be reasonable quality. I suspect the electrolytic capacitors will be first to succumb to working in a warm environment. I may fit higher temperature rated quality capacitors at some time in the future. I will be looking at the board with a thermal imaging camera to identify hot spots and general operating temperature. I am also looking at forced air cooling of the board after enclosing it in a case to isolate it from the build chamber. This is because I will be raising the build plate temperature to 80 Degrees C.
The controller board is used in other UP! Printer models. It just has different firmware loaded to suit. There are unused connector positions on the board and I have shown them and their designations in the pictures. There are two unused fan supplies that I may make use of to cool the board. A door interlock is not used and other models do not have doors so this may have just been included in case of need. There is an unused connector paralleled to the 3.5mm socket. These connections are for the automatic build platform height calibration system used on other models, but not the Mini.
The two unused fan supplies are designated fan 5 and fan 6 yet I cannot find fan supplies 1 to 4. One of the models must have a lot of fans ! The Mini has only one fitted to the extruder head.
A useful 5v supply connector is also shown on the board. I will investigate these unused connector positions to establish if they may be enabled and used for upgrades.
The 'CPU' is mounted on a daughter board to enable easy installation. This is presumably to facilitate easy upgrade or installation of model specific CPU's. There is nothing underneath the CPU daughter board. The microprocessor has a 16MHz clock crystal but it's identity has been removed by erosion or abrasion. Why bother with anonymising this chip I wonder ?
The V3 extruder heater assembly in now an all in one solution instead of being a machined aluminium block with separate filament guide, heater and thermocouple. The new design is made from a Diecast metal and IMHO appears to be a cheaper approach that is not as good as the V2 extruder heater. Unhelpfully the OEM has also changed the extruder heater mount dimensions to prevent use of the V2 unit. The OEM extruder heater assembly costs the same for both the V2 and V3 spare parts..... An eye watering £100 each
. Fortunately Chinese copies of the V2 are available for £26 complete. If my V3 fails, I will fit a modified V2.
Well that's enough comment for now. Maybe more later.
Fraser