gr5

Well the syringe extruder has been done on UMO and UM2 by several companies including this free version from Joris (who is a damn hack genius although he claims he's just an artist): http://www.thingiverse.com/thing:12430 There is a company that sells a very well priced add on to the UM2 - more professional than Joris version. I've seen them at shows but I forget their name. These allow you to use the E command (extrude) and so work great with slicers as is. No electronics changing. Joris version uses 3mm filament as a mechanical plunger-pusher. If you are extruding much less material you can use a lever to reduce the "throw range" and increase the precision of extrusion. I know this is kind of a hack but it sounds like you don't have electronics experts on your team already and it is a great way to test out the concept without changing any firmware or electronics. You just need to have the mind of a mechanical engineer and print the parts you need (or steal Joris design as is).

Lol. well that's the problem. The 0,0 point is in a different spot. So cura puts 0,0 in the corner but his printer probably puts it in the center of the bed. So when he prints in the center of the screen in cura it's printing in the corner on his machine and partly outside the build volume.

Wow. Glad to help.

If you just change the nozzle it shouldn't change the calibration but it might. If you get a little stuff in the threads for example. The nozzles are about .01mm the same. In other words the .25 and the .8mm nozzles are the same length. Not enough to be calibrated out. But 2 printcores could easily be .1mm different so you definitely want to calibrate at least once in X,Y,Z.

Also important - add towers BEFORE adding the model. In 2.4beta release notes I saw something about controlling the print order but I don't know where to find that feature. In cura 2.3 it's the order you place them on the bed.

>Can we replace the built in tower by 2 towers (1 PLA and 1 PVA) ? I don't know. You have to try it and then look VERY CAREFULLY at the path the head makes to make sure it goes to one of your toweres *before* it goes to the print. This is difficult to determine because that path could be going either way. But with the cura prime tower there I can see that it goes form the tower to and from the switch position and I know if I am looking at pla or pva (you click on those and the colors get brighter for the selected head) and I can figure it out. without the prime tower I'd just have to start up the print and not realize for a while if it was going to work. Or use some other visualization software like repetier. Cura won't show the order. Sure I just put two files here - I think it's the angle one: http://gr5.org/L_tower.stl http://gr5.org/angle_tower.stl You can use scale and adjust only Z height until it's slightly taller than the tower. And position realy really close to the tower but not quite touching. And use rotate to rotate the base of the tower as appropriate.

Oh. Also you probably want to use Cura 15.X and not the newer Cura 2.X. 2.X is a big rewrite and some features may be lost or hard to find. Cura 15.X supported lots of printers quite well - not sure that Cura 2.X is there yet (soon I hope). In cura 15.x you can go to machine settings and setup some of this stuff - like how big your build plate is and where the center of the machine is.

G92 is your friend. After cura creates the gcode file you can go in there and edit it (now don't panic - you don't have to do this every single time). Look at the gcodes - somewhere there should be G28 commands to home different axes. Later you can do a G92 to set the position. For example G92 X-20 should tell the printer that print head is currently at position -20. I've never tried negative numbers but it should work. Alternatively in cura check to see if machine type has the center at 0,0 or if the corner is 0,0. Usually 0,0 is at the home position. More on gcodes here: http://reprap.org/wiki/G_code I'm assuming through all this that your printer uses Marlin or Repetier or some other firmware that is on that above web page.

Oh! You are printing through USB? Don't use cura for that. Use pronterface. It's 10X better than Cura for printing. Sitck with cura for slicing but not for printing step. Get pronterface here. It's free: http://koti.kapsi.fi/~kliment/printrun/

The split is caused because the ABS is shrinking but you have crappy layer adhesion. You can't do anything about the ABS shrinking but bad layer adhesion will be a problem for all your parts. Layer adhesion is the second major issue people run into with higher glass temp filaments like ABS and is another reason PLA is so awesome. The problem is that as a layer is going down it is not fully melting the layer below so it doesn't bond well (never ever a problem with PLA!). The solution is not as easy as getting it to stick but here we go. First it really helps to heat the air. So as soon as you set your bed to 100C warmup put a box on top of your machine. I just use a random shipping box that fits close enough with lots of space in the back for the bowden. The boxes that are sitting next to photocopiers at work are the perfect size. also put some saran wrap or someting on the front of the printer. These 2 things should bring air temp from 20C to around 35C (hotter than 50C may be bad for your steppers but it's unlikely you can get the air that hot!) It also helps to lower the fans. For um3 I like around 3% fan. For UM2 I like around 30% fan. If you have zero overhangs and the part is large enough you can go to 0% fan. so for those 3 parts in the photo - if you print all three at the same time you will need a little fan for the holes but nothing else. But if you only print one of those at a time you will need a fan or the parts won't cool down very well and will look bad. It also helps to raise the nozzle temp but unlike PLA which has a huge printing range (180C to 240C) ABS has a very small printing range. If you go even just 245C and stop printing for a minute and walk away you will cause a nasty nozzle clog. So I usually am careful to never let the nozzle stay above 220C without it constantly printing. 240C is a good compromise ABS temperature. 230C is too low for me - I get layer bonding issues. Note that layer bonding issues aren't detectable unless you stress the part enough to break it. If it breaks along layer lines (ABS often does, PLA never does) then you have layer bonding issues.

If your nozzle "shoulder" has gotten wider @strat_elorenz that is bad news. Normal PLA will not do that but abrasive filament like brass fill, glowfill and especially CF filaments (and others) can rapidly destroy a nozzle. That wide shoulder will give you pretty terrible quality prints. I recommend you upgrade your core at my store here such that you can switch nozzles cheaply the next time this happens. Plus I sell steel nozzles for the hardcore: thegr5store.com

There are indeed several upgrades to the UM2 for dual printing but I believe foehnsturm's is the best.

I'm not sure I understand your question. Normal Ultimaker Core rated to 350C (not 250C!) Normal 3dsolex hardcore rated to 350C EHT 3dsolex hardcore rated to 360C (needed for PEEK) All of this is well above 280C. But the printer itself will allow the core to go above 355C without software modifications. So the EHT is for people who can edit the UM3 firmware and experiment. The hardcore six pro can go as hot as the normal Ultimaker core because (for now) it is using the same heater, the same temp sensor, the same everything - except the aluminum cooling fins, the block, and the nozzle. Aluminum and brass should be fine at 350C as far as I know. It is possible that Ultimaker is wrong and that it can not go to 350C. I don't know and I haven't tried that hot yet.

cura 2.4beta I believe now (finally) stops printing with the PVA nozzle once you are above all needed support. Does that help? Also you can play with the support "angle" and reduce the support on your particular model that way.

Let it soak at least 12 hours. And every 4 hours or so stick a toothpick in there and pull some out.

I assume Cura won't recognize that only one extruder is used if you tell cura you want pva support with the second extruder even if no support is needed. @mmichalka - did you try disabling PVA support yet? What happened? Did you make sure brim was turned off?

Cura doesn't control that - Marlin controls that. Please update your profile to say what kind of printer you have. You might want to update your printer firmware. I've heard of this bug before and I'm pretty sure it was fixed.

A clarification - the EHT is not all metal and should work with PLA but it's experimental - it has some unusual materials inside that can withstand the heat just fine but the question is will PLA stick to it and cause problems? Unless you want to experience the headache of bleeding edge technologies then stick with a core that we know works great for PLA and other materials up to 280C no problem.

So 41mm/sec X .4mm nozzle X .25 layer height is 4mm^3/sec which is a little too fast for 205C. I would go to 230C (which I've done on many prints) if you want to print at that kind of volume. Otherwise you will get a bit of underextrusion. Not sure if this is related to your sticking problem though - for that just move the bed a little closer to the nozzle - try 1/3 turn CCW. Also when using glue stick just use half coverage then wet a napkin and spread it around like the video shows.

It's hard to tell if it was underextruding because the filament wasn't inserted all the way (always make sure a little filament leaks out when you turn the wheel before a print). But if you primed the nozzle properly then this photo also looks exactly what you expect when the bed is too far from the nozzle. They say to zero it with a piece of paper but then you should turn all 3 screws another half turn or so to move the bed closer to the nozzle. You want z=0 to have the glass touching the nozzle (or even a little closer - touching with slight pressure).

Which version of the firmware do you have - you can get that from the UM3 control panel. I have not experienced this issue. I guess on the rare occasions I abort a print I probably don't do the cooldown.

Try removing all brim and support and see if that helps. Make sure Cura understands that this is a single nozzle print - you lose about 20mm (distance between the nozzles) on dual nozzle prints.

Don't go with EHT. It's experimental and the regular hardcore upgrade and also Ultimaker brand cores can print at 280C no problem. UM claims the core can go to 350C although I'm a little skeptical as they would have to use very special heaters and temp sensors to go that hot. Anyway 280C is no problem with existing core. EHT is an all metal solution [3dsolex corrected me - it's not all metal but still is experimental and can cause pain] that can cause you all kinds of pain. Most experienced people know to never use an all metal head with PLA. PLA sticks to metal and that's a major problem. You may do an entire print and it works great but if you let it cool down you probably will have trouble doing a second print as the PLA will be stuck. Also even during a print with a reasonable amount of retractions the PLA can get stuck and you will get a failed print. So stay away from EHT unless you plan to print over 350C. Also the firmware in the UM3 will not let you go over 355C. If the print head goes above 355C the printer will immediately halt the print with an error message. I don't know how to change this (yet) and don't plan to in the near future. Also the flat piece of silicone that the nozzles stick through at the bottom of the head - that will not do well above 250C. So if you will be printing at 280C remove that for those prints as the silicone will break down and crack and fall apart eventually after hours of printing at 280C.

I was planning to research this but... I have 8 other things I'm planning to do and the weekend is almost over. Keep bugging me about this or maybe if you are comfortable with changing software I can help you out and we can do this together.

I don't know how to go above 350C. Right now jedi marlin runs on the board that controls the temperature and it goes above 355C it will shut down the print job. So as a minimum jedi marlin needs to be edited and built. I think I can handle that as I've built regular marlin before but then I have no idea how to get that installed on that circuit board. Then also I believe you have to change some limits in jedi (I assume - possibly not mandatory). This is probably easier as it's all python I think. So you just edit it directly.