gr5

It's a feature, not a bug! I prefer it this way. It lets you see the model better. If you want to see the bottom layers you scroll the layer scrollbar to the bottom. The feature I really miss is being able to click one layer at a time. When you have over 200 layers it's very difficult to get to a particular layer to see what's going on. I'd like to see a keyboard shortcut for going up and down one layer at a time. Or buttons that only appear when the mouse hovers over them (to make the interface clean - like facebook does all over the place). An up arrow triangle and a down arrow triangle just like normal scroll bars. But anytime I can do something with the keyboard instead of the mouse is a win.

Looks pretty good. If you print the robot a little slower he will be less droopy because each layer will have a little more time to cool. You should notice quite a difference. Or if you do the same speed but print with more infill or make him larger. I've been thinking about adding a second fan so I can print small objects faster.

These images show the relationship between printing speed, nozzle temperature and underextrusion. Cube printed at .2mm layers.

I strongly suspect the arduino has op amps on all inputs but I didn't look it up. I doubt that 4.7K resistor made any difference either - you probably had a clog and fixed it at the higher temp and now the lower temp is working because the clog is gone.

Don't be afraid of building your own marlin. It's not that hard. You only have to edit Configuration.h which is 90% comments. Most of the settings are quite simple to understand and are either on/off or have values (e.g. steps_per_mm). If you find the dual extruder marlin that comes with cura to need tweaking, just go for it. Then ask specific questions about settings in configuration.h if you get stuck.

Do you have windows? Did you reboot the windows machine and reboot (power cycle) the UM with it unplugged from windows? When you plug the USB cable into the UM do you hear a sound from windows (guh dump)? If you go into device manager on windows does it show a new com3 device called "arduino" something? Under printers/com ports or some similar category in device manager?

Ultimaker is a business so I assume they prefer to keep their parts list obscure. What you are doing may be bad for the company. Not sure how they feel about this.

Glad that worked. Consider also doubling the wall if the part doesn't seem strong enough. Your nozzle diameter should be .4mm so 2X that would be .8mm so consider making the walls .8mm which is two passes around. That will give you more strength without hurting print quality too much. Or try a different infill pattern - hex instead of lines.

Did you consider checking the resistance when it is hot? Most resistors change their resistance significantly as you heat them. It's good for a heater to *increase* it's resistance as it gets hotter - for self regulation, safety, and faster warmup.

Here is a calibration run I made plus one someone else made. The first image shows that lowering temperature eliminates stringing. I used 4.5mm retraction. I printed slowly only because the part was so small and hollow that I needed time to adjust the temp and mark the lines with a sharpie and take notes all at the same time. I wasn't able to go down to 170C because when I tried, Cura turned off the extruder (that part not shown) and ruined the test. The next image was created by someone else (mo): https://groups.google.com/forum/#!msg/ultimaker/_1cPRgxGmOk/hDACjl0vO5QJ This second image is great because it shows you what under-extrusion looks like and if you hate those vertical lines in your print that are *not* ringing you can eliminate them by playing with temperature. The ringing lines you can get rid of by lowering acceleration and jerk. UPDATE - It might be overextrusion that causes the vertical lines. Instead of lowering temperature, maybe reducing flow by 5% would fix it.

Love openjscad. Very cool. Although I don't have a scroll wheel (just scroll buttons) so I can't zoom in and out - please add a second way to zoom (such as shift right mouse drag as openScad does). Or maybe there *is* a second way but it's not documented.

Did you consider turning off infill altogether?

Here is more details of what illuminarti is talking about. From his other post: http://umforum.ultimaker.com/index.php?/topic/1746-lack-of-extrusion-in-certain-part-of-a-part/?p=13006

Do you have joris turned on? SF (the slicer that cura uses) has some weird bugs when you combine joris with a part that doesn't have only smooth walls. The bug looks a lot like this and can be visually confused with underextrusion. More here: http://umforum.ultimaker.com/index.php?/topic/1746-lack-of-extrusion-in-certain-part-of-a-part/?p=13006

Good point, but the platform mainly only needs to move down. And gravity acceleration is 10Meters/sec or 10000mm/sec^2 so as long as you keep acceleration under 10000mm/sec^2 the greater mass will only help. Maybe there should be different accelerations for up and down but I think it's fine right now.

google building marlin and there are at least 2 sites out there with detailed step by step. I followed the steps and got it working pretty fast. Building your own isn't so bad. Read and edit configuration.h as needed for your heated bed. You will probably read 40 parameters but only need to change maybe 6. It took me about an hour the first time ever and most of that was reading configuration.h.

I assume you mean Z here as well. Did you apply the grease to the Z screw? If not read the assembly instructions again. Maybe add another drop? Try turning Z through same region by hand by spinning it near the bottom of the UM. It should be very easy to turn. So easy that moving the bed up is noticeably more difficult than down. If it's hard to tell the difference between up and down forces needed, then take the Z all apart. There could be something wrong with the 2 rods or the screw or the bed assembly. Maybe the rods aren't parallel enough?

Cura should notice the bed when you connect (when you hit print icon). Either you aren't sending the version of marlin that you built or the Configuration.h file isn't quite right. I'll post my Configuration.h which works for heated bed. Feel free to post yours also. Here is mine: http://gr5.org/Configuration.h

The coral reef look is probably under-extrusion. Either slow down or increase temp or tighten your feeder spring or increase flow. Slowing down is the most likely to fix it. If it weren't for stringing issues I would always print at 240C. Ha Ha. Yes, blue tape with ipa is amazing! For smaller parts or more delicate parts, consider not cleaning with ipa.

You should try kisslicer. In Cura you could try changing the print order. Default I believe is "perimeter - loops - fill". You would want perimeter last. Perimeter is the outer edge. Loops are inside circles such as a hole through your part - you don't seem to have any loops in this part.

You'll have to build it the hard way - yourself. google marlin. There are at least 2 detailed posts out there that describe how to build it yourself with step by step instructions. There's a lot of steps (e.g. you need the arduino IDE) but it's not too bad. I was able to do the whole thing (including lots of time reading the configuration.h file) in about an hour. The configuration.h file is where you set things like heated bed settings.

You have 2 issues. The holey pattern is typical under extrusion. Not enough plastic is flowing. Not sure why but I would try increasing temp by 10C or slowing down quite a bit as illuminarti said. More visual examples of underextrusion here: http://umforum.ultimaker.com/index.php?/topic/1763-bad-surface-on-printed-parts/?p=12318 Your other problem is very common with large parts and is caused by upper layers contracting and pulling on the bottom layer. There are a ton of fixes for this problem. I notice your infill is 80% which is the opposite of what you want to reduce the upper layers from pulling the bottom up. You probably won't like this advice but this will help greatly and is easy to do: put a layer of blue tape over the glass. Clean the blue tape with isopropyl alcohol (this is critical!). Your curling issue will probably go away. (don't forget to re-level). This will work better than anything else you can do. If that's not enough or if you don't like that idea, you can consider adding vertical holes in your part if that works for it's purpose. Also round the corners of your part - sharp corners lift more easily than rounded corners because all the force is on the tip of the corner. Also use that heated bed if you have one. Heat the glass to 70C and print the first layer at 240C, no fan, 40mm/sec then dial the temp down with cura or ulticontroller after it finishes the first layer of the part (not the bed) (this improves the stickiness).

Sometimes smaller layers come out worse for me. I try to stick with .2mm and tune everything for that. Anyway, my only suggestion is that to fix the top of your owl, in cura, the "bottom/top thickness parameter, under "fill" section should be 2 or 3X the value of your layer height. So if you are doing .075mm layers, make this either .150 (two layers on top of owl head) or .225 (three layers). This will greatly reduce the likely-hood of holes. I'm not sure if your blobs are due to overhang but if so then greatly reducing the speed will help. I can get almost horizontal printing at 20mm/sec. If you have an ulticontroller and are printing at say 70mm/sec then when you get to the chin of the owl dial it down to 40% (50 * 0.40= 20). This might also help with the top of the head. Else if using cura, then go to the tab with speeds and lower the perimeter speed to 40%.

This is classic "under extrusion". You could be slipping in the feeder - maybe you could try tightening the feeder. More likely you can fix this with higher temp. What temp are you printing at? Since this model has no stringing problems (for example if you had 2 vertical posts, you might get stringing between them) you could go up to 240C no problem. But later on other models you will get stringing so maybe just go up by 10C from whatever you are printing at now. Or slow things down a little bit to reduce the pressure in the print head. See this also: http://umforum.ultimaker.com/index.php?/topic/1763-bad-surface-on-printed-parts/?p=12318

I'm sure it was missing a partial step on every layer to be that consistent. I think these servos are driven in 1/8 step increments maybe? Does that make sense? You could have also fixed it by lowering "jerk" and acceleration to ridiculously low values.