anon4321

I would agree with Jonny and suggest you just buy the full V6 bowden version. Buying the pieces you need will only save you 10 or so pounds. With the full kit, you will have options. Since this is still experiemental, having a backup plan is good. So for me, I'm going with the UM1 block, heater and TC. Jonny is apparently going with the switched out 24V E3D heater, thermister and in general the standard E3D V6 design.

Re tubing cutters .... I think you can print one too! Thought I saw a model for one. Hmmmm, the linked version certainly seems printable... Here: https://www.youmagine.com/designs/bowden-tube-cutter

You might want to add: E3D - 30x30x10mm DC Fan v6 Spare Fixings Bowden Coupling - Threaded (3mm Filament) Note also that the bowden tube is sold in lengths of 100mm and the UM1's tube is 670mm so you need qty = 7 If you are reusing an existing UM1 alu block, heater and TC. You don't need any of the stuff from UM. Otherwise, you need what you have listed plus 1052 Heater Cartridge 18V 40W Heater Cartridge (1)

My initial thought was to use this as a way to transfer printing experience to those new people like me. The intention is highlight different techniques for getting the best print so that finishing is minimal.

Yes, reinstate the script!!!!!! I'm not doing twitter! A single thread with everything is better than nothing.

Well, there are three potential areas of compatibility problems and an additional one caused by addressing the others - Issue 1) Heater voltage - The heater that comes with the full E3D kit is 12V while the UM1 uses 19V. Using the 12V one that comes with the E3D hotend is probably not a good idea, Fix: reuse the heater from the UM1 hotend. HOWEVER, in my case, I have noticed that the heater is stuck in the block so strongly that I decided to order a second one from UM. Issue 2) Temperature measurement - The UM1 standard end uses a thermocouple and the E3D kit comes with a thermistor. Fix: two and a half possibilities - Fix 1) Use the thermistor that comes with the E3D kit but you will need to solder a 4.7k ohm resistor to the UM controller and then rebuild the FW so that it expects a thermistor in place of the thermocouple. You will also need to cut the connector of at the hot end and correctly wire the thermistor to the wire harness. Fix 2) Use the thermocouple and it's amp board from the UM1. NOTE a few things however. The alu block that comes with the E3D kit doesn't appear to have a hole deep enough to accept the TC Like the heater, the TC also tends to stick in the UM1 block after being used for a time AND can be easily destroyed trying to remove it Most E3D head replacement designs don't have a provision for mounting the amp board required for the UM1 TC. Fix 2.5) Use the entire UM1 alu block with the UM1 heater and UM1 thermocouple (good if both are stuck in the block). NOTE: However this leads to Issue 3 Issue 3) If, to address issues 1 and 2, you reuse the UM1 alu block note that t[he UM1 block appears to be slightly thicker and may alter the tip to mount distance by a few mm. It is also slightly bulkier and may interfere with the various fan shroud designs. Issue 4) Bowden tube - I'm not sure about this one. If the E3D hotend can accept and clamp the UM1 Bowden tube, there isn't an issue. If not, you need to buy a tube from E3D as well as the feeder side coupling There might be other problems but they might not be discovered until someone attempts to put everything together.

Also note that I believe (I don't own a UM2, I have a UM1) the UM2 power supply comes from Meanwell which implies that it has both over current and over temp protection so make sure the PS isn't overly warm and has adequate ventilation.

Not sure what you mean by command line but if you want to issue hand entered gcode or need a pronterface type interface, go to File -> Preferences and change the printer window type. This will replace the plain "print" window with a pronterface type UI and there is a text box for directly issuing commands to the printer.

Hey Jonny, I think you modded or built a UM1 with upgraded 8mm rods (for direct drive). Did you get the rods from Misumi? If so, what are the part numbers? And what tolerance bronze bushing did you use?

3dguy, I think it hit most of those links. Thanks, I'll relook at them.

I wonder how important the length is... The obvious important dimension is the 8mm ID. The OD is less critical as any custom XY blocks could be adjusted to 12-14mm OD. There looks to be approx. 5mm extra on the length in the standard UM blocks. Obviously, a shorter bushing could work. However, I wonder if it would allow more angular play. Or in other words, would shorter allow the smaller axes to deviate from 90 degrees more than the 30mm versions? Since the smaller rods are driven at both ends, does it matter?

Anyone know where someone in the US could source the 8x11x30mm sintered bronze sleeve bush(ing)s used in the XY blocks? I want to print a second set of XY blocks and kept the originals intact.

Me? An Application Architect? Overcomplicating things? Nah...

The SSR is a common approach. See this for some detail discussion. http://umforum.ultimaker.com/index.php?/topic/6014-heated-bed-build-and-a-question-about-the-z-stage/&do=findComment&comment=55219

Daid, how much "inter" layer information is required during slicing? Slicing seems like a perfect candidate for multithreading. In fact, over simplifying, If you have say 4 cores, if you virtually split the model up in the vertical direction into four objects, the could almost be sliced individually (in mind overly simple mind). so if the object is 20mm, you give the first thread the first 5mm, the second mm 5-10 and so on. The critical things would be to know that the part being sliced is in the middle or is the top or bottom piece and then ensuring that the gcode is adjusted so that first layer and last layer processing is done correctly, fan codes are right. I guess the biggest problem is knowing the filament length because you need the part below the current part being sliced to be sliced to know how much filament has been fed. Or could you just zero the filament length at the start of the "sub" part? I just retraction would get screwed up doing that... or would it? Very interesting problem.... I wish I had your job!

Does too high of a temp exacerbate the problem?

The time it takes is related to the number of facets on model has. I've seen it take 20s+ to slice a complex but valid model on a 3.1ghz I7. Since it's single threaded, the best thing to do is throw clock cycles at it so make sure if you are using a laptop on battery that the CPU is running at max frequency.

I believe that will always be the case when you have a cylinder on it's side. The first issue is that I believe Cura slices the bottom layer differently using a thicker slice based on the first layer setting. See page 23 here: https://www.ultimaker.com/spree/uploads/38/original/Cura_User-Manual_v1.0.pdf I'm sure your first thought would be to reduce that value but the value is chosen to help with the second part of your problem which is bed leveling and distance to nozzle. In order to use a smaller first layer value, you would need to precisely adjust the level of the bed and it's distance to the nozzle. This is almost impossible to do down below .2mm Here are two suggestions that might help. Print the object on a raft. See page 27 at the link above. Or use MeshMixer to levitate the part about 2-3mm and then use it to add support under the part. See

http://hackaday.com/2014/06/18/3d-printing-directly-onto-your-ipad-screen/

If it is the fans, look for something misaligned that causes something to cool that shouldn't. I don't know the UM2 and the head design is very different than the UM1 so I wouldn't even want to guess what is getting cooled.

Just a shot in the dark but I'm having a problem where the bottom layers separate and I think it is temp related (on a UM1). However, it go me thinking on this. Since you are getting good first layers, are the fans coming on for later layers causing something to cool, underextrude and grind? How far do you get if you switch the fans completely off?

From the firmware source - #define DEFAULT_AXIS_STEPS_PER_UNIT {78.7402,78.7402,200.0*8/3,760*1.1} // default steps per unit for Ultimaker These values represent the X, Y, Z and extruder stepper motor steps per mm. So if the gcode calls for the head to move in the X direction 100mm, the firmware will issue 7874 steps. If the gcode then has the head move back 50mm in teh X direction, the firmware assumes it is starting at 100mm and so steps in the reverse direction 3937 steps. This works as long as what IRobertI mentioned is true. The steppers must be strong enough so that steps occur when requested. If the steppers "miss a step", the print will be off as there is no feedback that the miss has occurred.

No, steppers are open loop control. The firmware establishes "home" or 0, 0, 0 using the switches. From then on, the firmware tracks the steps away from 0, 0, 0 to know the nozzle's location.

Nevermind.

Or do you mean an arc? I don't know where you got your information but this lists the gocdes supported by the UM2 firmware. If you are talking about arcs/circles, you want to use g2/g3 https://github.com/Ultimaker/Ultimaker2Marlin M23/M24 are for controlling a print from the SD card and M32 doesn't seem to exist.