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Yes, those will work on UM1 and many other reprap style printers. They will not work on UM2 which has an integrated heater block/nozzle. My mistake - they are only $1.52 each. I recommend drililng them out to different sizes. .4mm is great but .8mm is also a very useful size - you can print much faster. 4X faster. with only a small loss to resolution. .6mm nozzles and larger don't clog nearly as easily either.

To post a picture click "Gallery" on the top left of this page. Then click big blue "upload" button. After uploading create a ne post and click on "my media" next to smile icon and choose "gallery images".

UM2 nozzles are I believe $40 plus another $40 for shipping possibly. Although I suppose in the USA shipping is probably only about $5 as they will most likely be shipped from Ultimaker USA.

ebay! It's wonderful. They come from china of course so you might have to wait a month.

Oh - then you need to build your own like stated above. ? Try again - use marlinBuilder again. Click the very large button. Right click the "hex" file and choose "save file as...". If you open it in a text editor it should something like this: :100000000C94040A0C94B00C0C94E10C0C94120D9A :100010000C94430D0C94740D0C94A50D0C94D60DFA :100020000C94070E0C94250A0C94250A0C94250AAE : If you are on a PC you might have to rename the file to extension ".hex" before using Cura to send the file to the printer.

So this sounds like a different problem than the topic. You can connect just fine, right? Do you have an ulticontroller? that makes things so much simpler. If not you should control the printer with pronterface is it will give you much better diagnostics - free download here: http://koti.kapsi.fi/~kliment/printrun/ So you say the extruder heats up? I'm wondering if it is getting a MAXTEMP error. I don't know how to test this without an ulticontroller because I only use ulticontroller but pronterface might be able to tell you. Also you should use the version of firmware that comes with Cura. Have you gotten that to install onto the arduino yet? Other versions of Marlin will not work with the heated bed as this is a unique way to do the temperature measurement and doesn't match any of the existing temp probes in normal Marlin firmware. So start Cura from the begining with the wizard and answer the questions "UMO" (not umo+) and HBK (heated bed kit) and see what version of firmware it supplies you.

Both heaters are controlled with a switch. In PID mode they typically switch 10 to 20 times per second. You can see the LEDs flashing when the heated bed gets within 10 degrees below goal. This is because the 24V is changing enough for the LED's to dim when it's on. So this is basically current control. But the voltage is not measured and accounted for. power is proportional to voltage squared so a 2X change in voltage is a 4X change in power. The PID controller can handle the wrong voltage just fine but it takes a minute to adjust. If the voltage keeps changing, the temp is often wrong. However this should not be a problem on a well designed board and power brick. The brick should be able to put out 24V +/- .5V with bed on and off. Anyway this is all still just an untested theory.

People say that really old glass windows are thicker at the bottom because glass is a liquid. Supposedly when you go through the math you would have to leave that glass vertical for thousands of years so I don't think it got bent inside your machine.

Buy the countersink. You will use it for other things. Maybe not this year but I found mine to be incredibly useful for many projects. And it deburrs holes also. It's just a handy, cheap, light weight tool. I suspect it's impossible to permanently bend the glass due to the screws. Of course you could flip it over and see if it corrects, lol. Like someone else said you need to countersink those holes or the air gap will cause other more serious problems (bed at wrong temp). UM Support can send you a new bed but it will probably take a few weeks. It's easy to open a ticket. There are probably large profit margins - just do it. Don't worry about it. As far as buying tempered glass, what is the price for ordinary glass? I hear that works fine.

By the way the easiest fix for above (if the voltage change is consistent across printers) is to measure the two voltages when bed is on and off and it's very easy to compensate in the PID algorithm if you know the change in voltage and knowing if the bed is on or off at the current moment.

I'm thinking something much lower frequency. I can always come up with 10 theories but the simplest one for now is that when the heat bed is on it draws so much power that the voltage going to the nozzle heater drops significantly maybe from 24V to 19V e.g. The problem could be the brick itself or the traces are too thin somewhere along the heater path or other resistance (connectros, FET). Then what happens is when the heat comes on the bed the PID controller for the nozzle thinks it has the perfect PWM for nozzle heat but it doesn't realize the voltage dropped a lot so the head cools. After a few layers the head gets back to normal temp (goal temp) and then the bed heater shuts off and the voltage goes up. Then suddenly the PID doesn't realize this change and the nozzle gets too hot for a few layers. Eventually the PID controller gets the nozzle back to goal temp only to have the problem repeat every minute or two. This is just one possible theory but it explains everything. I have already come up with a few other theories that seem less likely and more difficult to investigate. This one should be investigated first.

Like cell phones, wifi, quadcopters and other radio receivers. Don't fly too close to the UM2!

Of the bed or the nozzle? I'm not surprised at all about the bed. But my theory is that the nozzle temp changes significantly when the bed comes on versus off.

1) Are you certain retraction is happening at all? There are 6 or so settings that control it. You can verify it in layer view. 2) Please post a picture because what you call stringing we might call something totally different like "bad Z axis" or underextrusion. 3) Consider increasing retraction distance. When my UM2 was new 5.5mm was perfect. Now that I have the bowden tube locked tight in the print head and it never moves up and down anymore I can do 4.5mm and that's perfect. 4) Some brands of PLA do a small amount of thin stringing no matter what you do. 5) Printing very slow (e.g. 20mm/sec) greatly reduces pressure in print head and reduces stringing to pretty much zero. But you shouldn't have to go this low. I recommend printing some kind of stringing test part like the first photo here: http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/ Then modify settings like retraction distance, and print speed WHILE it is printing.

I hear makerbot is even worse. Sorry - that's not much of an endorsement. If you phone tech support they often answer immediately (call before 10am your time). However, you should post any problems you have on these forums. You will get very fast answers and learn a lot!

I also heard it jumped recently from 2 weeks to 6 weeks. Don't know why but I know they are shipping. You may have been better off ordering from makerShed since you are in the USA. Their ordering website is much clearer about if they have them in stock or not and you get the same service after you receive it.

By the way in other tests I found bang-bang mode still kept the bed (not a UM heated bed) at a constant temp within 1C. So I think the problem has more to do with the 24V supply. Or maybe it's a firmware bug related to interrupt service routines?

Unlikely. Sorry. Because PID mode creates too much electromagnetic interference and violates CE certification. But Daid *might*. I mean most people don't care that much about a small amount of EM noise. Meanwhile someone at UM will hopefully figure out if this is a rare problem (certain power supplies) or if this is a common problem to every UM2. Personally I have not updated my firmware in several months and am now reluctant to do so. :wink:

I suppose it could be causing problems for the Z stepper but much more likely it's the head temperature swinging through various temperatures. The bed uses the most power so when it is on the voltage probably changes a bit and may affect the nozzle temperature somehow either by messing with the temp sensor (seems unlikely) or by changing the characteristics of the nozzle heater (now at lower voltage) that messes up the PID controller and causes some overshoot.

They (other cura plugins) probably all use the M0 command. I think your question is more a printrbot question - see if there is another command (e.g. M1 which I think is also pause) that would work better for the printrbot. Does the printrbot have any kind of control panel? I think repetier might be able to *not* send the M0 and instead stop sending commands and you can tell repetier to continue sending gcodes. Cura I don't think knows how to do that.

I'm skeptical. UM is getting away from USB printing. They mainly support SD card printing and in the future wifi printing but USB printing is an "old technology" and they are looking to the future. Having said that, you can pause just fine using gcode command or using panel (although from the panel there is a 20 or so movement delay because of the buffering). At least on UM machines. Don't know about printrbot. So I think you are going to have to stick with repetier or pronterface for printing.

I set the filament width to 2.85mm a few years ago and never touched it. I don't think it matters as much as some think.

jim can't receive messages until he validates his email. There is no qty limit. The 3 posts is so that moderators don't have to approve his messages. jim I'm skeptical about any reliability differences between the printers. The heated upgrade kit is well worth it. I don't have to level anymore and I can print ABS. The underextrusion is probably worse on the UM2 if anything because the motor has less power (on purpose) so that you get skip-backs on the stepper instead of grinding the filament. Nozzles are $5 each including shipping so I'm not sure what that problem is exactly. Replacing a nozzle on UMO is just 2 minutes once it warms up. It's 20 minutes on the UM2. Plus nozzles are $40 I believe (not including shipping) on UM2 and only UM sells them so... "win UMO" when it comes to nozzles. The UM2 main advantage is it looks nicer (to some people) and it is quieter. These were not among your complaints. It sounds like your bowden is damaged - if you take it out of the head too often or without releasing the metal blades that hold it in place it gets scraped. I recommend you get a new bowden tube instead of a new printer. I'm told the reliability of other manufacturers 3d printers is MUCH WORSE than Ultimaker. Especially the latest line of Makerbots which have nightmare problems with the extruder assemblies. You might just have been unlucky with some parts of your UMO. Or maybe you print too cold. Or too fast. Or maybe you have a dusty environment or maybe your feeder creates sawdust that makes it's way through the bowden to the head. Maybe your thermocouple is off such that you are printing colder than you think. Emotionally you may be tired of fixing your UMO - and don't want to buy a new one. But I recommend you stick with your existing one or buy another UMO kit.

It's not software. It's hardware. You say your pulleys are tight but you need to tighten the hell out of the setscrews. Also most people tighten only 8 pulleys but there are 12. 6 on each axis. Usually it's the 2 hardest to get to: the ones on the motor and the other one on the short belt. Is it moving "all over the platform" in X and Y or only in one direction? A picture would be nice. See 9th and 10th photos here (pink part and leaning robot): http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide

I think they are told not to comment on this subject. They promised it first quarter 2015 for UM2. It's been available for about a year now on the UMO so consider buying a UMO instead. They made a major breakthrough on it a few months ago.