gr5

I haven't looked at the new kickstart code in Marlin but will it kick on every increase? Even if increased from 10% to 25%? I hope so. I don't see why you think running a fan at 10% duty cycle will damage it. Yes it will heat up. But not much - why do you think it will be damaged? Many cheap fans are much too smart these days - they have circuitry and voltage regulators and tachometers and they won't turn on until around 60%. And they run no faster at 100% than they do at 60%. I don't know why they are designed this way. Many people change their fans to some fan they order online and there are many types out there and they all need the kick at different percentages and such and there are hundreds of different fan models out there. I don't think Cura should worry about this - this kind of thing should be built into Marlin - you should be able to configure each of your printers to have their own custom Marlin (pretty much this is done already), and each Marlin should know if the fan can withstand PWM mode or not.

Everything illuminarti said will help the "spaghetti" aka overhangs. Lowering nozzle temp a bit might help also. Also if you want to improve the quality elsewhere, slow down the print to 35mm/sec (or even 20mm/sec if you have all day!) do .1mm layers and cool the temp of the PLA down to about 210C. Don't lower temp without also lowering the speed - at lower temp the PLA gets thicker (like toothpaste) and can't be extruded as fast.

.02mm is the resolution in Z but the nozzle has a hole in it on the UM Original and UM2 that is .4mm in diameter. Or .2mm in radius. That means in XY you can't print anything smaller than about .4mm. Also it means you can't have sharp corners any sharper than a radius of .2mm in XY plane. However you *can* print objects "sideways" so that you get the best resolution in a particular dimension. If I print a knife flat on the glass bed I can make it amazingly sharp - sharp enough to cut my finger. But if I print it vertical it will be quite dull (.2mm radius). I recommend you look into the b9creator (google it). This can print equal resolution in X, Y, and Z. Not just Z. Or look at the more expensive form1. I believe you can use the prints from these printers as investment casts.

There are many options to turn on and off when you build Marlin. The version number is not related to what features are supported (such as heated bed).

Photos or video might help. Did you use paper to level? It sounds like it's just a tiny bit too close (nozzle to bed). I don't understand why you level and then it seems to ignore your levelling.

You might only need to tighten all the pulleys. Tighten the heck out of them. The hex screw should twist a bit. There are 5 per axis on the UM2 (6 on the UM Original). The most important 2 are the one on the motor and the other one on the short belt.

I don't know but I know there is a strong spring in there - it's probably easier to loosen a single pulley than move a single block.

printbl.com in USA is great vendor - really high quality stuff. The downside is the filament reels that they sell won't fit on back of UM but not huge deal - I usually put it on the floor anyway. Or you can build one out of knex or something. If the filament hits 3.00mm you should be fine but 3.05mm tends to be too much and tends to jam in the bowden. I've talked to people who had to remove *both* ends of the bowden and heat the whole thing in boiling water to get the filament out.

I understood you the first time but I'm not convinced 45 is better. It just means you approach it slower. You could instead slow down by 70% and get the same effect. Actually better because if you slow down you are less likely to get underextrusion as well. The root of the problem has more to do with overhangs and how the lip of an overhang (raised edge) gets too high and the head hits this and sometimes the part comes off the bed. There's some discussion of this in another thread but there was no complete "cura". You can partly help by doing less overhangs, and also doing more fan helps quite a bit and printing cooler. But these don't eliminate it completely. Also there is some theories that thicker layers would help but no one tried it. I think ABS doesn't have this problem as badly also because ABS cools so damn fast.

Many filaments are labelled "3mm" but are actually 2.9 or 2.85mm. You need to check carefully as some really *are* 3mm and those won't work in the UM. Anything from 2.85 to 2.9 is fine (that's a small range - I know) assuming approximately .15mm tolerance. What country are you in? Someone may recommend other sellers of filament. Please update your profile settings to include your country in "location" part.

What printer are you using? Are you using Marlin firmware? Do you know the jerk setting? I recommend printing much slower - print at the jerk setting speed. For Ultimaker's that would be 20mm/sec. I'm no 100% sure this will solve all your problems but it will greatly help. There are 3 factors that cause vertical holes to be smaller than desired. The first one is shrinking and for abs is about 6%. The second factor is the "rubber band" effect that Robert partly described. The 3rd one is qty of points on a circle since CAD software inscribes the polygon *inside* the circle instead of outside of it. However the 3rd factor doesn't seem to be much of an issue for you. The fix is to increase the hole size in CAD. Try increasing all of these holes in CAD by about .5mm plus an additional 5% (or 3% for PLA). Do not increase *outside* dimensions also by these same amounts - typically you can increase the scale of the model in X,Y by 5% but not Z (3% for PLA). Printing with thicker layers should also improve the quality of these holes. I would try .2mm just for an experiment. Also if you print at 20mm/sec you can print much cooler - try 230C for ABS. You will get slightly less of factor#2 (rubber band effect).

1.2 is smart to try. Gives it more layers to recover. 240 would help the plastic flow - also smart. I see two problems in the image - one is very clear and obvious to me. You have a loose belt or belts. Probably the short belts (slide the motor down harder). When you have loose belts you see diagonal passes on the top - you see 2 passes close together and then a gap. Here is more discussion on this - read post #7 and #8: http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=14396 Also you may have some underextrusion after you fix the backlash. Underextrusion can be fixed by printing slower or at higher temperature. Fix the backlash first.

You can cut the power immediately - in fact the most sensitive chip, the voltage regulator, runs just as hot if printing or not.

DM=Direct Message To do a DM click here: http://umforum.ultimaker.com/index.php?/user/423-sandervg/ Then click on "send me a message".

you only have to loosen two pulleys on the long belts on each axis. If only one axis is messed up you only have to loosen 2 pulleys.

No. You don't. I want to see your part in layer view and in normal view in Cura only. I do not want to see what it looks like printed. You already told us the layers are missing in cura slice view - so why would you then print it and be surprised.

I also like the recent idea of always overextruding bridging such that there is enough plastic to create a .4mm diameter string (equivalent of .4mm layer while in the air but not when over other layers).

That would be very nice!

What fingerpuk said. I recommend putting the filament on the floor. This rubbing causes problems and slowly grinds up the black ABS plastic that the feeder is made out of and that ABS plastic gets dragged eventually into the nozzle where it causes serious problems in the nozzle such as blockages or reduced ability to extrude.

The brass nut I was talking about actually isn't visible from the bottom. You don't have to take anything apart - just raise the bed and look at the 4 screw heads closest to the big Z screw from below. Make sure those 4 screws are tight. That's all. This was a problem for someone else who was constantly losing his level due to the bed being loose there. Personally once I set my Z level I don't have to touch it for a month.

I don't understand about loosening screws. Did I say to loosen screws? The 4 thumbscrews should be tight. The bowden itself can be locked down better if you want but isn't mandatory. I think I suggested a longer retraction distance (more than 4.5mm - maybe 6mm is right for you).

If there is wood debris you can usually see it by removing filament and looking into the feeder with a flashlight - you don't have to take anything apart. Test boiling by touching a drop of water to the aluminum block. Use finger or qtip ear swab. Also room temp should read about 20C when the machine has been off for 30 minutes.

Swapping from ABS to PLA takes lots of experience and practice but usually results in clogged nozzles. You might want to remove your nozzle and burn out all the plastic and then soak in acetone. Certainly you want to get all that ABS out of the bowden and out of the feeder before you start a print. ABS, if kept hot for too many minutes slowly cooks into a very difficult gunk that will require special effort to remove from the nozzle.

This is a common problem on the UM2. I suggest you go over to this thread and print this test piece at 230C which will test out your thermostat, extruder path, feeder, bowden, filament, everything at once. It is *critical* you test at 230C even if your problems are at 210C. http://umforum.ultimaker.com/index.php?/topic/4586-can-your-um2-printer-achieve-10mm3s-test-it-here/

Something is wrong with homing. You need to check 2 things: 1) With power off and the bed in the up position look underneath the bed at the brass colored nut that the z screw goes through has 4 screws holding it to the bed. Make sure those are all tight. 2) Sticking out of the bottom of the bed should be a very long (30mm?) screw that sticks down. When the bed lowers it goes down through a hole in the bottom of the UM2 to hit a switch. Please examine that switch. If you lower the bed by hand with power off, does it touch the switch and make a click sound? Consider putting the UM2 on it's side so you can look at the switch as the screw hits it. 3) If the switch seems fine, consider removing the larger cover on the bottom of the UM2 (only 2 screws hold it on) and check the "z limit" signal as the wire traces from the z limit switch to the connector on the printed circuit board. When you start levelling it does a Z-home procedure where the bed goes all the way down. Does it make a horrible death rattle sound at the bottom? Or does it click the z home switch gently twice?