tsp42

It is not the easiest filament to print with. I had a lot of trouble with the nozzle clogging most likely due to small residues of colorfabb HT filament but after cleaning the noozle with a gas torch the problem disappeared. Now I'm struggling with underextrusion of the first layers. Post-processing is easy as the filament is rather soft and gives a really nice copper shine. I did upgrade my hot end to E3D v6 but mainly for printing high temperature filaments as copperfill did print fine on the standard UMO hot end. I will try testing the ammonia on some cheap PLA in the weekend to see if it still works.

I might have found by accident a new way to dissolve PLA that might be useful to remove PLA support from print. At least it worked very well to dissolve my headphone cups that I printed with colorfabb copperfill filament when I tried to oxidise the copper. I placed the headphone cups in a closed plastic container with a small cup filled with ammonia water (25% solution). After 24 h the copper had turned into a very dark blue colour. When I tried to remove the cups from the container the outer layer more or less peeled off and the plastic had turned very soft. I haven't tried to repeat the experiment with ordinary PLA filaments. If you are going to try this, please do it outdoors and use gloves as ammonia is corrosive and not very healthy to breath. ABS appears to be resistant to 25% ammonia water so this may be a useful way to remove PLA support.

It only took 1½ year but I finally replaced the fan, power supply and added a heated bed (JasonK mk 2) to my UMO. The frame is a slightly modified version of the template from formfabrik. The fan is an old 12V Papst 4412 FGL 120 mm fan (55 CFM so plenty of air). The power supply is a 24 V 15 A Chinese no-name PSU adjusted down to 21.1 V. I intent to replace it with a Mean Well SP-480-24 PSU (20A). I used a 5A step down buck module to replace the 12 V regulator and feed the fan. I used the ARD PWR jumper to bypass the 7812 regulator. .

jonnybischof: Do you also use digital current control(page 24 in the datasheet) like the UM2 or only the POT for setting the current? And do you thing that the INDEX pin (pin 21, page 33 in the datasheet) could be used to detect skipped step? And do you have heatsinks on the chips?

Dintid you are welcome to write a PM to me too in Danish. I have ordered some DACs to implement software current control in software like the UM2 if it has any interest.

Not really. Antibiotics are usually added to the culture media and you really don't want any possible adverse effects from the unknown antibacterials added to the filament. The best filament to use should be completely biological inert or alternatively just support the attachment of the cells to the plastic.

http://www.ncbi.nlm.nih.gov/m/pubmed/16179758/?i=1&from=Acrylonitrile%20butadiene%20styrene%20cell%20culture Making a new ear? I would be a little worried about what could leak out of the plastic during cell culture that might affect the cells even if it is not cytotoxic. Natural PLA might be safer considering it is not made from oil but who knows. Please let us know when you have tested it. Maybe ultimaker could sponsor 6 microarray assays...

SkinnyChicken: The two chips are not pin compatible so no it is more complicated than that (redesign of the mainboard)

SkinnyChicken: the steppers drivers are soldered on the Ultimaker 2 mainboard so it will rather difficult to replace them. Ararax: not sure if there is any improvements with the new forum.

Just finished installing the SilentStepStick on the X, Y and E axis. I can confirm that it is not necessary to remove the CFG2 jumper. It is sufficient to open the MS1 and MS2 jumper on the Ultimaker mainboard. I would be nice if ataraxis could update the first post, but it look like he is yet another casualty of the new forum. It is very impressive how much the noise is reduced with the new drivers. Certainly a plus for the WAF. Another thing, to get the 1,2V I had to adjust the sense resistor to 8,6 kOhm resistance between VRef and Gnd

Is it really necessary to desolder the CFG2 bridge? From what I can see from the Ultimaker schematics opening the MS2 jumper will leave the CFG2 pin floating as it is not pulled to ground (only MS1 is pulled to ground).

Thanks for the feedback. Will give it a try when I get the time to do it. The TMC2100 chip on the SilentStepSticks fortunately has a overtemperature detection so they should turn off before being cooked. Not sure if there are other hotspots on the PCB (besides the voltage regulator)?

I was wondering if anyone has tried replacing the electronics cooling fan on the original ultimaker with a standard 12V 120mm fan blowing directly on the pcb (no wodden cover)? I going to replace both the stepper drivers with the silent stepper driver and the 12V voltage regulator so less cooling should be needed.

See also this thread.

I'm not sure it would work. Did you try to reflash the arduino MEGA? Else try creating a simple test program in the arduino IDE for testing the different pins on the arduino MEGA. Or just buy a cheap arduino MEGA2560 clone. You can get one from €14 at amazon.de

Sounds like the arduino mega is broken. Sort of makes sense as the arduino is powered by the 12V regulator.

I would think that a rotary tool with a flexible shaft might be a better fit for the ultimaker to keep the printer head weight down.

Found a place for a replacement 24V fan if/when the 12V fan burns out: http://www.ebay.co.uk/itm/1-pcs-Brushless-DC-Cooling-Fan-24V-5010S-7-Blades-50x50x10mm-3pin-Sleeve-bearing-/260961280654 An alternative approach could be to use a 47 ohm 1W resistor to lower the voltage to 19V.

A couple of related Google groups threads: https://groups.google.com/forum/#!topic/ultimaker/B8Ac4CfqFoE https://groups.google.com/forum/#!msg/ultimaker/4CWoBH7Odm4/aJLUipN1QlQJ If the 7812 is only used for the arduino then a voltage between 7-12V should be acceptable.

Yes didn't see that, thanks. So they should be safe to use with a 12V fan.

Thanks, so the ultimaker PCB wiki and the Ultimaker assembly guide that mentions a 12V allways on fan header is wrong and should be updated to 19V? So the 12V is only used to power the arduino?

It is a 120 mm 12v 0,08A case fan to cool the ssr and buck. It doesn't have to be PWM controlled so I can draw the power directly from the buck. Are you sure the that fan that cools the pcb is controlled by a transistor? I thought it only was the 19V fan on the print head.

Is it really that simple? I've brought a 24V PSU and a 12A DC DC buck step down voltage regulater and I did intent to use the buck to deliver 19V to the ultimaker but it may make more sense to set it to 12V and use it to replace the 7812 instead. This would also mean the 12V fan output will be able to deliver a lot more current?

Got it working on an Ultimaker original using the convertor on http://en.homeconstructor.de/converter-convert-music-in-g-code.html I changed the G00 code to G92 and moved the Z axis to a safe distance from the nozzle.

@polar: I couldn't found a distributor for setfuse neither so I ordered a SEFUSE SF139E instead. It is a 250 VAC/15A fuse with a 142C threshold. I intent to test if it work with DC current and hope that 24V is low enough voltage to prevent arcing.