gr5

I don't know if cura supports relative movement. Probably not. The UM printers support it I think. Anyway, why is this so hard? Just have one variable for x,y,z,e axes and subtract the gcode from the current location and that gives you your incremental movements. Very easy. Actually incremental movements are a problem. A serious problem. If there are floating point errors (and there will be) then errors can build up and what will happen is that each layer will be shifted a bit from the layer below. So really - incremental gcodes won't work very well for 3d printing.

I don't have any good ideas. Maybe someone else can test this. It *looks* okay in thingiverse but maybe it's corrupt or something. If it were me I would simply slice it in cura 15.X.

Okay I think I found a bug in 2.7 beta. Or maybe it's in the "0.8 pla fast" profile. Or maybe this is on purpose. I just downloaded it and installed it yesterday (clean fresh install on a computer that never had cura installed before). When I choose AA 0.8 cores and just do the recommended print it does two shell passes (two!). This is much slower than 2.6.2 which does one pass[correction it also does two passes but... profiles are different]. Zooming in on things (customizing) I see this (all default settings): Notice I chose AA 0.8. Notice that the default wall thickness is 0.97. Why not 0.75? This is supposed to be the fast profile. And why are the two shell passes different thickness: inner .62 and outer .35. Isn't .35 a bit too thin for a 0.8mm nozzle? I mean it does it. It doesn't look horrible. But it prints much slower than if I did a single .75mm thick shell pass. I mean on the forum I'm always telling people that the 0.8mm nozzle prints 4X as fast (.6mm nozzle 2X as fast). You can print twice as thick (e.g. .4mm thick layers) and you can print with one wall pass (0.8mm thick walls) for 4X the speed. But now I realize that this is only true if they use cura 15.*? Or if they go deep into the settings. Because if all I change is shell thickness from 0.97 to 0.75 cura *still* does two passes on the outer wall! with a 0.8mm nozzle! You have to go drill down and edit inner/outer line widths to get it to do one pass. Is this a profile bug? Or is there a good reason to do two pass shells? On a "fast" print? The "extra fast" and "sprint" profiles all do the same thing. But when I changed inner/outer line and wall thickness all to 0.75 the print sped up by another 20% (43 minutes instead of 53 minutes).

As a test you could delete the first three travel moves for 20 layers in a row to see if that helps. G1 X74.771 Y111.774 E1487.24266 G0 F9000 X74.596 Y111.678 //del G0 X74.838 Y111.24 //del G0 X89.372 Y89.414 //del G0 X89.8 Y89.342 //del G0 X89.8 Y89.842 G1 F1800 X89.8 Y139.642 E1488.89902 The ones above that say "del" are useless. It's faster to just move directly (green line in screen shot above) the other moves are too tiny to be useful and I suspect your printer is taking too long to do them or your firmware does something weird with these tiny/short moves. If that fixes the problem then you would know a lot more. For example a square hole might be better. Or maybe you could reduce the polygon count in the cad model of the round holes. Right now they have an excessive amount of movements. Actually that could be the whole problem! Do you have the original cad model? Can you edit it? I'm guessing yes. If so when you export to STL try to make those holes have only maybe 10 line segments - not the 50 or so they have now. What happens is the planner inside the printer typically only has 16 move look ahead and has to be able to stop after 16 moves in the future so it has to slow down for those short line segments because it needs to be able to stop within a mm or so. But if 16 line segments are at least 5mm distance then it can print them much faster. The speed change of doing those vertical holes to suddenly doing a long straight line (like a highway) causes your underextrusion.

Oh! S3D! Does S3D lower the temp of the non-printing nozzle? That is a critical feature of Cura. Also consider printing at half the speed you have been printing. If you print too fast you get high pressures in the nozzle and that can cause grinding. For a .4mm nozzle a safe volume (for testing) would be 3 cubic mm/sec.

Does 80C bed work okay with buildtak? I find with larger ABS parts I need a bed temp of at least 100C. 105C is better. Otherwise the corners tend to warp/lift off the glass. Also I hope you use a front cover and top cover to keep the air warm. This has nothing to do with clogging though. And keep the fan at 1% or you will get bad layer bonding.

Oh. Why ABS? I guess my first advice would be to stay away from ABS. If you need high temp materials maybe consider ngen? ABS is harder to print and it tends to be weaker than PLA. It warps and shrinks more. It creates bad fumes while printing. If you need a higher glass temp material there are other options - nGen from colorfab is a good intermediate glass temp material - higher glass temp (not as high as ABS or nylon) but still easy to print like PLA. Not sure if it works with pva or hips though.

Ug. Well I'm biased as I sell these but I'd buy a 3dsolex hardcore with swappable nozzles so you don't have to throw away a print core - that way you can take the nozzle out and clean it or worst case just throw away the nozzle. So ABS will bake into a kind of gum if it gets too hot for too long. 255C for 10 minutes should be plenty to make a core useless. Only fix is to take it apart which is difficult as these are delicate. Or buy a new one. So I recommend sticking closer to the 240C end of the range. 270C is just asking for trouble. But if you go any cooler than 240C (and even at 240C) it's hard to get good layer bonding and your parts can look and feel fine but they are actually quite weak along layer boundaries. So ABS has a narrow printing temp range (unlike PLA). This is reason #16 and #17 why ABS is not an easy material to work with. If you are doing dual materials with HIPS then you want the cool temperature of ABS to be way down near 200C. or lower. I don't have enough experience with this to know - I've only done one dual filament ABS print on UM2 and it came out fine - I didn't touch the profile temps. But if ABS is sitting at say 220C for a few minutes while printing HIPS it *might* clog. Probably not at 220C for just 5 minutes but still... did you use the default profile temps for ABS cool down temp? Anyway your clogs might have nothing to do with this if you are printing at 240C. It might be that it's grinding for other reasons. I really doubt your problem is dust. It's more likely that you are creating clogs because ABS is too hot for too long or grinding for other reasons. You could just be printing it a bit too fast or with too many retractions. You don't want the same piece of filament going through the feeder over and over more than 10 times or so. Typically PLA has issues around 20 times through the feeder so limiting that to 10 is good for PLA. I would expect ABS to be slightly more flexible and less likely to grind up so I would expect it could also handle 10X through the feeder but some prints like vornoi and all kinds of prints sometimes have excessive retractions so check that as well. Anyway... some things to think about.

PVA is difficult and fidgety and not as reliable as PLA. But it's just support so when the pva fails in some way the print is usually still awesome. But if you were to pancake your printing with layers of pva between... I don't think you will like that. You can lay PLA on top of a pva structure just fine. But not the other way around so much. If you print PVA on top of PLA it will not stick well at all. So there is this nice cura feature just for this purpose: "horizontal expansion". It means the pva sticks out from the pancakes (like syrup?) and reaches all the way to the bed. This helps tremendously. Also bits of pva worms get everywhere (because - it's sooo different from PLA in mechanical properties and doesn't stick to itself so well). Also pva is quite expensive. And switching nozzles takes typicaly 5 to 10 seconds which doesn't sound like much but this is an extra delay on every layer. But the UM2 and UM3 are really great work horses. That I will agree with. Strongly consider the UM2 though - fewer filaments means less setup time and fewer things that can go wrong. People seem to think the UM3 is better, but it is just... different. it can do 2 materials instead of 1. But the UM2 has been around longer and had many improvements (the plus!) and is a great machine and much cheaper. Or get a few i3 printers, lol.

Mostly I think it's the time thing. The extruder takes a little time to stabilize at a given pressure inside there and everytime you speed up or slow down you get over or under extrusion until it stabilizes again. z-hop is a feature that delta printer people use a lot. I believe. It's not helpful for Ultimaker printers.

Cura profiles have the ability to have different settings for different colors but - there are already too many combinations (something like 4 core types X 5? materials X 4 quality settings X 2 cores) that adding color to the mix will make it difficult I think. Anyway as of august 2017 there are no profiles related to color. All the cura settings (speed, temperature, fan, etc) are the same for all the colors.

You are correct that you have to also buy the hardcore printcore from 3dsolex. So it's a big expense for just getting the ice coating. I'm not sure if it's worth it or not. On the other hand if you were thinking about buying a .8mm core anyway then you can save your money and get the 3dsolex and get other nozzle sizes: .25 .4 .6 .8. I sell 3dsolex products in USA so I am a bit biased.

If the pva isn't sticking in a back corner (tower) then it's probably your warped glass even though you got a better quality glass from your manufacturer. But if it isn't sticking in the middle... maybe clean the glass again really well. About once per month I wash the glass in a sink and get everything off and use soap and warm water. Then I rinse and dry and use glass cleaner and dry one more time. Then I put it back into the printer and apply PVA. One way is to use a little glue stick (really not much!) and then use wet tissue and spread it around. heat up the wet glass to 60C until it all dries out. It dries out about the same time it reaches 60C.

Thanks kristel!!! it's good to hear from a real material engineer! >My part is thin so maybe this is normal for Nylon Okay - that I think is the main issue. Nylon is quite flexible. If you print parts with thick sections then you might not notice so much. But Nylon is sooo much more flexible than PLA or ABS. That's mostly what makes it so strong and tough - you can usually drive a car over a part and it will just flex and bounce back to normal after. It's not the tensile strength that is impressive about nylon. It's the flexibility combined with almost the same tensile strength as pla or abs. Never fear dropping a nylon part onto a hard floor. PLA - be a little more careful.

We should stop replying in this thread. The guy made 2 posts a month ago and never followed up. I don't think he ever came back and read any of the replies.

All metal sucks for pla. It's really a miserable solution if you plan to print PLA. And PLA is the most common printing material because it has such a wonderful combination of good properties. The problem with metal is that melted PLA sticks to it incredibly well. You might be fine for a while but after too many retractions it will likely get stuck and your print will fail. Or after the printer cools down you won't be able to start up the next print as the filament is locked/bonded to the cooler portion of the hot end.

This sounds like a leveling issue. It sounds like your nozzle was farther from the bed than desireable. Next time you aren't happy with the bottom layer try shoving the bed up or down a little just to learn what happens.

Oh also - ninjaflex doesn't need a very hot bed. Whatever your bed temp is, lower it by 10C. Probably 35C is warm enough for ninja to stick well. Unlike most plastics, Ninjaflex doesn't have warping issues - it won't warp off the bed because it is so flexible it would rather just bend a little. So you can probably go colder on the bed. The heat from the bed also probably makes that overhang a bit ugly.

Oh right. ninjaflex. Probably 100% fans. It's heat deflection temp of 44C is quite low making me think it probably bonds well at pretty low temperatures. Like pla. Really you know fan is too high if the part is breaking along layer lines. What can happen is one layer isn't sufficiently melting the layer below and you get very weak bond from one layer to the next. The problem is the lower layer is too cold and the layer being applied doesn't heat the lower layer enough to melt into it. This never happens with pla. One of many reasons pla is so easy to print (many reasons!). With ABS it is a constant worry. With many other higher-temp materials (nylon) it is also a problem. I suspect it's not a problem with ninjaflex but I haven't printed enough ninjaflex to know. I would assume 100% fan is the best until you find out otherwise. It will certainly help the overhangs. It just might make the part weaker.

You may be right that a 3d printer is not for you. You can always order prints online. 3d printing takes in my opinion quite a bit of learning. It's not like a 2d printer. buying and learning a 3d printer is more like buying and learning a milling machine. It's not too bad but you need patience. I don't know of any other FDM printer more reliable and easier than the UM2 or UM3. But it's not trivial.

definitely turn off zhop. Yes the .25mm nozzle is less forgiving. The .4mm nozzle with .2mm layer heights often looks better than .05 layer heights. The thicker the nozzle and layers the more forgiving things are. But you should be able to print a nicer looking benchy with .25mm. Let's hope it's just the zhop issue. I'm wondering what else you might have messed with. Bed temp should be at 60C max (no hotter). 60C should be fine. 55C might be slightly better. I see the hull overhang could be better - are your fans at 100%? You want as much fan as possible with this model and with pla in general.

The graphic above and the gcodes are from the exact same region of the file. gcode.ws is an amazing website. Notice I checked the box "emulate extrusion width" for this analysis. I also played with turning on "mm extrusion per move" and looking at the "layer info" tab. The layer info tab indicated there were only ever 2 extrusion rates (flow rates). One was for the bottom layer which must have been thicker (that's default in cura - thicker bottom layer). The other was for the rest of the print. No 3rd extrusion rate. I urge you to play with this tool. Anyway - I see no bugs in cura in this situation. There is something weird with your printer - probably in the firmware.

Here's the relevant part of the gcode: G1 X75.9 Y113.408 E1487.17481 G1 X75.829 Y113.136 E1487.18416 G1 X75.723 Y112.865 E1487.19384 G1 X75.588 Y112.607 E1487.20353 G1 X75.421 Y112.364 E1487.21333 G1 X75.228 Y112.142 E1487.22312 G1 X75.009 Y111.945 E1487.23291 G1 X74.771 Y111.774 E1487.24266 G0 F9000 X74.596 Y111.678 G0 X74.838 Y111.24 G0 X89.372 Y89.414 G0 X89.8 Y89.342 G0 X89.8 Y89.842 G1 F1800 X89.8 Y139.642 E1488.89902 The movements with an "E" term include the extruder - those are extruding moves. The 5 G0 moves without the E are non-extruding - those move from the circle to the part where it underextrudes. The E1488.89 is extruding about 1.6mm of filament which according to the gcode analyzer (image below) is the same rate as everywhere else (.022mm/mm). I looked at 2 layers - one with solid infill near bottom and 1 with cross hatch infill about 1mm up. Same results. So in summary the gcode looks fine. I think it's your printer. Sorry. And there is zero retraction on this one. Maybe it's because there are 4 travel moves before it starts printing again. The UM printers have very high jerk setting - about 20mm/sec so they blow through those tiny moves almost instantly. Maybe your printer is leaking/oozing during that. Or maybe the motion planner inside your printer has a bug. Motion planners are very complicated. I've rewritten one and looked at the code in Marlin and Repetier and other motion planners and there are hacks and bugs in all of them.

There's 2 gcode files there. Which one is the latest at 30mm/sec and with combing turned off?

Oh! That's not a bowden printer. The feeder is right on the head. Make sure retractions are very low. 2mm max I'm guessing. 4.5 is much too much - lets air in the nozzle. I'd try 1mm or 2mm. That printer accelerates more slowly than a UM also. Hmm. I'd try 20mm/sec for all speeds. You can just dial down the feedrate to 50 to 66% as a test on each layer and see what happens. You can do 5 layers at 100% speed, 5 layers at 50%, 5 layers at 25% and see what is the right speed in this area. I'm quite curious. Then once you know you can have cura print the bottom layers slower and speed up after it's done with that area. I'm still confused as to what is going on.