Now have ABS working on this printer and printing that flared cone thing in ABS.  Up to 52mm and just over 30% filament used and alright so far.

Mostly printing fine and up to 75mm but a couple of blobs have appeared.

On ‎22‎/‎05‎/‎2018 at 20:19, Gina said:

Print finished and looks virtually perfect.  Printing time 1h 23m.  The 300mm steel rule shows the scale.  That print is BIG!!

 

Working well now after all that effort you could use that to blow your own trumpet and deservedly so 

Dave

Thank you

The finished ABS trumpet and new fume vent duct with fittings and hole in the wall into the broom cupboard in the kitchen.

Fume duct from other side.

I have a problem with the supports for the print bed when set at 120°C for printing ABS - they're softening and the bed is sinking   I used PETG and that doesn't take the temperature.  I'll try ABS or maybe Nylon

I've given up on brackets for now and added 40mm M5 screws in each of the four corners of the aluminium bed plate to space it away from the sheet of OSB I'm using as a base.

Now I have another problem - the Duet WiFi control board is reporting :-

Quote

Warning: Error: Short-to-ground on drivers 1

I'll look into that tomorrow in daylight - I can't see anything wrong ATM. 

If it's not one thing it's another - means leave it - tomorrow is another day!!

Found a wire broken on one of the connectors.  That would certainly stop the motor working, just hope it hasn't caused the driver to fail

Just done a quick test by moving the working motor connector to the other driver and the motor drivers are working - PHEW - looks like the £150 worth of board is alright.

Duet WiFi board is fine :)  Changed some wiring to add more tolerance and shortened some wires where excess length was catching up.  XYZ moves now working properly.  I'm now going to try a print run with ABS - the large trumpet shape but taller.  With the new bed supports it needed re-levelling and here is the cold bed automatic calibration results.

Strangely the bed level has gone way off now whereas last time it didn't make much difference.  Bed temperature of 110°C.  Of course calibration needs to be done at working temperature rather than cold so I'll adjust it to give the automatic compensation less to do.

This will do.

17 hours ago, Gina said:

If it's not one thing it's another - means leave it - tomorrow is another day!!

Perhaps you should change your name to Scarlett 

Dave

Now attempting to print with some very cheap ABS that I've had in stock for several years.  25mm/s and hotend at 320°C to melt fast extruding filament.  Print bed at 120°C for first layer then 110°C.  Bed heater will also heat cabinet to help with warping.  With higher temperature and slightly lower speed I'm hoping this print run will work.  Layer height is 1mm with the 2mm nozzle.  Extrusion multiplier at 1.3 and extrusion width set at 2mm.  That should help with inter layer adhesion.

That print came off the bed at around 40mm.  So I've added some ABS slurry to the aluminium bed and kept the bed at 120°C.  I also opened a sealed bag of unbranded ABS filament so no chance of moisture absorption and so perfectly dry filament.  This print has now reached 70mm without failing.

It was going fine well past halfway and getting very late so I went to bed and left it running as I often do.  This is not supposed to happen (the mess on the narrow part) ??

I think that's due to insufficient part-cooling. Also when the layers are that small they dont set solid before the next one causing the deformation.

If you are using Slic3r look at the cooling options. You can make it slow down on small/short layers.

But as a piece of art it would probably sell for thousands ?

I also have some other failed prints that look quite artistic ?

Had a complete rethink about cooling the heatsink on the hotend and decided to ditch the water cooling and go back to standard air cooling.  The thinking behind this is that the amount of heat to shed from the cooler side of the heatbreak only depends on the nozzle temperature, the thermal conductivity of the heatbreak and the temperature needed on the cool side to prevent the filament softening where it shouldn't.  The available power input is higher in the Giant printer due entirely to wanting to melt more filament in a given time.  The control system supplies only enough power to the heaters to maintain the required temperature for extrusion.  Granted that the printer is enclosed and warmer than ambient when printing ABS or ASA but these filaments have a higher softening temperature anyway.  I shall be using the same cooling system as in my Titan printer which is also enclosed and warmed inside and that cooling works perfectly well.

As a result of the above the X carriage is much simpler and interchangeable hotends become relatively easy.  The other change is to use a bigger fan for parts cooling as the previous one proved insufficient.  As a result the air duct and "blower" parts have also been redesigned.  Interchangeable hotends mean that the heatbreak does not need disturbing when changing nozzle size - nozzle, heater block, heatbreak and cooler will be changed as one unit.  It also means that the alternative size of filament can be accommodated.

Well, air cooling turned out to be inadequate when using a high bed temperature and warm chamber - cooling with warm air is not efficient.  Consequently I have returned to water cooling but with a simpler and lighter waterblock.  I've used the standard E3D V6 heatsink and printed a water jacket to go round it, directing water flow across and between the fins.  The V6 heatsink is sealed to the ABS printed jacket with O rings.  This has proved totally leakproof once I had applied acetone smoothing to the surfaces in contact with the O rings.