Gina

I think the spool holder print is probably usable if not very good - poor perimeters and lots of whiskers. Still needs a fair bit of tweaking!

A couple of photos of the top of the printer. I still have a front for the Duet box to design and print.

Now printing a spool holder for this printer while borrowing the one from my Titan in the meantime. Using PLA.

Heatsink temperature is still holding at 42.8°C to 43°C after 30m. I conclude that the cooling water is circulating purely by gravity. Q.E.D.

Looking good. Here are some screenshots :- Starting point with temperatures nearly back down to ambient. After 5m with hotend set for 260°C but not extruding, cooling system filled with water but not enough for circulation. Heatsink warming up. After 20m with cooling system full of water and purged of air. After 25m and heatsink temperature holding at just under 43°C. This is well below the glass temperature of any known filament.

I now have the printer powered up and everything connected. The main 24v 15A PSU fan is well audible (and I can see why @tekkydave added a manual control to make his quieter). I added code for the new thermistor to the Heaters section in config.g plus another Tool in the Tools section and now have the heatsink temperature displayed Currently there is no water in the cooling system and the screenshot below shows the heatsink warming up with heating the hotend. Initially the heatsink was at about 23°C. Tool 0 is the normal hotend heater and thermistor, Tool2 is the heatsink (no heater connected) and the third item is the Bed. The Temperature Chart shows the three temperatures graphically (Red, Green, Blue). Here is the config.g file :- ; Configuration file for Duet WiFi (firmware version 1.20 or newer) ; executed by the firmware on start-up ; ; generated by RepRapFirmware Configuration Tool on Wed Jan 31 2018 19:48:21 GMT+0000 (GMT) ; General preferences M111 S0 ; Debugging off G21 ; Work in millimetres G90 ; Send absolute coordinates... M83 ; ...but relative extruder moves M555 P1 ; Set firmware compatibility to look like RepRapFirmare ; Automatic saving after power loss is not enabled M667 S1 ; Select CoreXY mode M208 X0 Y0 Z0 S1 ; Set axis minima M208 X450 Y450 Z800 S0 ; Set axis maxima ; Endstops M574 X1 Y1 Z1 S0 ; Set active high endstops M558 P4 H5 F200 T9000 I1 ; Set Z probe type to unmodulated and the dive height + speeds G31 P500 X40 Y0 Z1.23 ; Set Z probe trigger value, offset and trigger height M557 X50:450 Y20:400 S200:190 ; Define mesh grid ; Drives M667 S1 ; Select CoreXY mode M569 P0 S1 ; Drive 0 goes forwards M569 P1 S0 ; Drive 1 goes forwards M569 P2 S1 ; Drive 2 goes forwards M569 P3 S0 ; Drive 3 goes forwards M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation M92 X80 Y80 Z3200 E418.5 ; Set steps per mm M566 X900 Y900 Z12 E120 ; Set maximum instantaneous speed changes (mm/min) M203 X6000 Y6000 Z600 E1200 ; Set maximum speeds (mm/min) M201 X500 Y500 Z250 E250 ; Set accelerations (mm/s^2) M906 X800 Y800 Z2400 E1500 I30 ; Set motor currents (mA) and motor idle factor in per cent M84 S30 ; Set idle timeout ; Heaters M305 P0 T100000 B4725 C7.060000e-8 R4700 ; Set thermistor + ADC parameters for heater 0 M143 H0 S150 ; Set temperature limit for heater 0 to 150C M305 P1 T100000 B4725 C7.060000e-8 R4700 ; Set thermistor + ADC parameters for heater 1 M305 P2 T100000 B4725 C7.060000e-8 R4700 ; Set thermistor + ADC parameters for heater 2 M143 H1 S301 ; Set temperature limit for heater 1 to 300C M106 P1 T45 H1 ; Tools M563 P0 D0 H1 ; Define tool 0 M563 P1 D1 H2 ; Define tool 1 - Currently used just to show heatsink temperature G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C ; Network M550 PGinaRep Giant ; Set machine name M552 S1 ; Enable network M586 P0 S1 ; Enable HTTP M586 P1 S0 ; Disable FTP M586 P2 S0 ; Disable Telnet ; Fans M106 P0 S0.3 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off M106 P1 S1 I0 F500 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on M106 P2 S1 I0 F500 H1 T45 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on ; Custom settings are not configured

I shall try gravity circulation for the cooling water and to tell how well it's working I shall use a thermistor in a hole in the heatsink and connect it to the temperature on the second extruder system (only using one extruder and hotend so the second is not being used and can instead of the usual function can show the heatsink temperature). I've drilled a hole in the heatsink block and inserted a standard thermistor helped by some thermal grease and held in place be a bit of scrap extrusion. Extended the wires and terminated in a 2 pin connector to match the Duet board connector.

Cooling fan has arrived. Now to change the Duet box design to take it.

Another go at printing the reservoir, this time using Spiral Vase mode with increased extrusion rate and lower printing speed to keep within the extruding capability. At last success Watertight! Went on to drill holes for inlet and outlet pipes 3D printed) and glue them in. Yes, that's water in there

It leaks!! And I don't mean out of the pipes - it leaks through the body of the tank!

Decided to print the reservoir in ABS and make it it three parts - the body and two pipes and solvent weld the parts together. With the reservoir and the water block both having low and high connections I think there's a fair chance of the water circulating by gravity as in gravity fed hot water systems (the water block representing the boiler and the reservoir the hot water tank). It will also have a lid to keep dust out and prevent anything else dropping in.

The cooling water pump has failed

The design works but with a 0.5mm wall thickness my Titan printer is not quite accurate enough to produce a perfect wall and there was a leak a few centimetres up. This would probably be cured with a greater extrusion width. Here's a photo. Not the full height as it ran out of filament. It can be seen that most of the wall is pretty good but the lack of rigidity in the bed carriage can be seen in places and hence the need for the Titan re-build. See my Titan printer blog.

My idea worked Hopefully a watertight container! Used Spiral Vase mode but set the number of bottom layers to 6 corresponding to the thickness of the fixing lugs (3mm). First layer 0.7mm subsequent layers 0.5mm so 6 layers = 3.2mm.

Well, the reservoir printed perfectly except for one thing - it leaks at the seam, where the layer step is

I've had an idea which I might try tomorrow.

OK - printing a new reservoir without inlet and outlet pipes and with a single perimeter wall for maximum transparency. Pity it isn't possible to switch to Spiral Vase mode after printing the base with the fixing lugs. At least it doesn't seem to be in Slic3r. It would be nice to do away with the join where it jumps to the next layer.

Print not satisfactory due to problems with the support material for the pipes. I can eliminate the top one by feeding the water tube through the lid. I could eliminate both by feeding both tubes through the lid and using the syphon effect as I have been doing with a squash bottle but I was hoping to have the outlet at the bottom at least. I'm using colourless PETG which gives an almost transparent wall but this stuff sticks so well to itself that the support wont break off.

Printing the water reservoir.

Lid.

Water reservoir. I shall also print a lid for it to keep dust out.

24v 15A PSU with cover containing bed heater SSR and buck converter for +12v plus mains ON/OFF switch.

You probably don't need a cooling fan at all then. Just mount it vertically (as you have done) with plenty of room for air flow across the back. This is what the WiKi says if you're not using more than 2A for any of the motor drivers. My Z motor driver gets hot but not too hot to touch. Just want to be sure the board doesn't fail after hours of use.

New power wiring diagram.

I think I'll arrange that air from the fan can also get round the bottom of the board and up across the front as well as the main flow over the back. I've ordered one of those fans, Dave. Due to arrive Monday.