yellowshark

I have a similar problem in a room above the garage with no heating. I bought an oil filled radiator four years ago which does the job for me. it probably runs on no.2 out of 6 or so and keeps a constant temp of 20-22 at that level, at a cost that we do not notice

Line width? I think the setting is called Infill before walls, under Infill. Infill overlap is the amount that the infill overlaps the walls, in my usage that means the inner wall. Skin overlap - well I have never seen a post where it is stated what the skin is. It was never referenced in 15.04.and it appeared sometime in 2.nnn; I have 2.7 and it is referenced in that version. I assume that the skin is what used to be called the outer walll and I assume skin overlap is how much the wall next to it overlaps.

Inner wall before outer wall; walls before infill; print slow; print cool; 1.5 is a strange wall width - what is you defined nozzle size, line width and number of walls?; 15% infill overlap. Personally I would swap to blue for moment until it is perfect and then try the white which as @Smithy said is often more difficult

A lovely model Bob. Is that different coloured filament or is paintwork involved? The central grey pieces look exquisite, how did you achieve that?

For the past 5 years I have had a z-offset command in my printer definition start gcode section. Just wondering why one would write a plugin to replace a single line of code - or does it have some extra goodies :)

If you have the model loaded in Cura 3.xx can you go to the scale icon on the left hand side and tell us what the x/y/z dimensions are please.

Hi John, OK there are a lot of factors involved in your questions and I think it is helpful to split them in two. Generally speaking under extrusion results from a hardware problem. Firstly your filament. If it is wound on the reel really tightly, and being 50%+ through your reel will exacerbate this, then the filament can stick when it is coming off the reel. If the filament is poor quality then its diameter will vary and go beyond specification and stick in the Bowden tube. Good filament is 2.85mm +/- 50 microns. Poor filament can go to 3.0mm and beyond and will stick. All feed systems have a filament drive wheel which is either at the start of the system and pushes the filament or at the end of the system and pulls the filament, which is how the Ultimaker works I think (?). Allied to the drive wheel is the pressure spring which determines how tightly the teeth on the drive wheel grip the filament. If the spring is too slack then the filament can slip when the drive wheel is trying to move the filament. Conversely if the spring is too tight then pieces of filament can be “eaten” by the wheel and lodge themselves between the teeth; the end result being the toothed wheel that becomes a smooth wheel and again the filament slips. Plus if you have an Ultimaker then the drive wheel is, or was, plastic with a fairly short longevity. My drive wheels are metal and are the same ones that were fitted to the printer when I bought it 5 years ago. The point is you need to keep on top of your drive system. I have never experienced it but I guess you could have a duff or damaged Bowden tube which would cause the filament to stick. Finally you have the extruder and nozzle and burnt filament stuck in here will cause under extrusion. And yes if you print with .300 layers at 100 mm/s with a temp. of 180 and a 1.2 nozzle you will likely under extrude – but you would not do that would you J OK before moving onto over extrusion let us first change your mind-set. In your software settings you do not use layer height to control under/over extrusion. Layer height determines your resolution i.e. the quality of your print. In principal I guess you could use it to control extrusion but then you lose control of quality, bad. You use layer height and print speed to control your quality and time needed to print the model. You use extruder temp. to control the extrusion. Over extrusion comes from printing too hot and a lot of people print too hot. Just because the specs of a PLA filament say you can print at 220 or 230 that does not mean you should use that temp and yes when I was a beginner I used to use 210/215. These days I use 190 +/- and I cannot remember the last time I went as far as 200. I would advise you to print as cool as possible, for the settings you are using to deliver the quality and time you want. Looking up a volume table to get the extruder temp – which someone else has produced. Don’t know. Bear in mind that everybody’s printer is different; at any moment in time your drive system could be highly efficient or it may be poor, the same for the guy that produced the table; even different colours of the same manufacturer’s PLA can have different extrusion characteristics. I have always followed the discipline that when I try a new filament I test it and find the optimum settings for me.

Pretty difficult to be prescriptive on this one. Not only is it required mechanical clearance but you have several other factors – plastic shrinkage, printing of circular geometry, dimensional accuracy of your printer, flow characteristics of your feed systems and settings plus potentially your filament. I have found a clearance of 100 microns generally to be too tight when fitting a printed screw to a printed thread; so my starter is usually 200 microns. If too tight then I will add 100 microns until OK and then I will back of 50 microns to see if that is better. Of course if you do reprints with different settings or different filament or different printer then you may need to resize. It maybe that if you are printing screws/bolts to fit manufactured metal nuts etc. then you may find that once you have established your modifier it will always work, but I have only ever worked threads plastic to plastic so I do not know.

What are your settings for print speed(s if different);retraction settings if turned on; layer height; model x/y dims

I would not use a temp of greater than 190 with those settings. White tends to be the most problematic, if you can swap to a different filament. If it still delivers bad results then as @Smithy says maybe you have a hardware extrusion problem -probably best to do an atomic pull (plenty of posts on that in the forum)

OK I understand. Well two things, check that that area of the bed is clean. If you use adhesive it may be worth cleaning that are and reapplying the adhesive in that area. But possibly the real solution is to press the filament more firmly into the bed by reducing the bed to nozzle gap. Yours does not look particularly pushed in, certainly less than mine and others I have seen. Put a big (x/y axes) cube on the bed with a brim and start the print. Adjust the setting by turning the three adjustment screws equally and you will see changes in how the 1st layer is laid down. You can take it to the point where the filament is almost invisible and then back it off a bit. These days I have my filament pushed down quite hard and set the flow for the 1st layer to 70% with 1st layer extruder temp set the same as the extruder temp for the main print. It is a combination that works very well for me.

The very easiest solution is to print a brim or a skirt. OR are you saying that happens on every layer not just the first?

Beware computer colour matching, it is normally not reliable. Their service offers an an injection moulded block in your colour, which is a fabulous service. For UK users and probably others they will translate Pantone codes into the European RAL/REL codes (one of those two!)

Set Z seam alignment to "Random"

… if you start getting adhesion problems then either spread PVA or spray hairspray

I would suggest.. Set 1st layer bed temp to no more than 65, even try 60; 2nd and subsequent layers set bed temp to 50, certainly < 60 You do not say but set 1st layer layer height to 0.3 You do not say but set 1st layer print speed to 20 mm/s For the moment I would set print speeds to 40mm/s or lower. If you must print at 70 then set No. of slower layers to say 5;set Regular fan speed at layer to say 6 I set my 1st layer flow to 70 and then increase it 10% each layer to get to 100% Use a brim

@Smithy is right it is not under-extrusion, well unlikely anyway. Also I am not convinced either that it is bed levelling - although a non level bed will do you no favours. Your first pic shows it to be seemingly random; if your bed is not level say on the x axis then if the left side of the bed sticks OK by the time you get over the the right side it may not be sticking, or the bed is so close to the nozzle on the right side no filament can get out. The point is that as you move from left to right the stickiness will progressively get worse or get better. I suspect you have one of several problems... Your bed is totally knackered - as @smithy and I have both said run a straight edge over the bed to see if it is OK. You have a build up of adhesive - no idea what if anything you are using - clean the bed thoroughly and retry Your bed to nozzle distance is incorrect, too small or too large; I suspect it may be too large, try to set the bed up so the filament is really squished down; you can do this in real time although probably a bit trickier with 4 screws rather than 3. Your bed heater may not be very efficient; i.e. and e.g. whilst the centre of your bed may be at the correct temp., the peripheral areas of your print area my not be - wait longer (10-15 mins) to ensure the bed is all at the same temp desired temp. Better still measure areas of the bed with an IR temp gun I think it will help us if you print a 1*0.3 layer and send us a photo

Probably one of two problems given that it extrudes OK if you manually feed it. Your filament is not good (i.e. too wide in places) and is sticking in the bowden tube. If you are pushing the filament through the tube yourself you should be able to feel this and if you have an appropriate tool measure the width of your filament at various points to see if it is OK, 2.85 +/- 0.05. Maybe more likely is the knurled wheel that feeds the filament. This has an adjustment which modifies the pressure of the wheel on the filament - too loose and the filament feed will be inconsistent or not happen at all; too tight and you will eat into the filament. Pull out the filament and finger touch the filament at a point after it has been through the wheel. There should just be a very slight roughness; if smooth the wheel is loose and not engaging; if really rough then you are too tight. Also if you have been printing too tight then small bits of filament will start to clog up the teeth in the knurled wheel and eventually you will have a smooth surface instead of teeth and the filament will slip and not be fed properly or not at all - you can clean the stuff out with a sewing needle.

You are probably printing too hot. For 0.15 at 40mm/s I certainly would not be over 190. Probably best that you print a normal say 10*10*10 cube and see how that comes out with your settings and then try again with 190.

OK well I would say that with a height as low as 0.6mm then problems with a bed, such as uneven spread of the adhesive material could easily show on the top layer, especially with such thin layers that only compound the problem*. I am not saying that that is causing what you are seeing, it looks random and spread all over the print area which is a bit confusing. It would be interesting to see the result if you set the height to 1.2mm and printed 4x0.3 layers. * as an example if you are printing 20% infill and 0.3 layers and specify 3 top layers you will just about get a smooth top layer. If you print 0.1 layers and specify 9 top layers you will not get a clean top layer. The thinner you go you need additional thickness to get a smooth top because the individual thinner layers are not good at covering the infill and transfer unevenness up to the next layer which all builds up and you need more thickness to cover it all.

If the areas on the sides are level then the print bed will need to be warped for the inner section not to be level. Take a straight edge, metal ruler?, and gently wipe it across the bed; you will see if it is warped. Bed levelling only affects the first few layers, something many beginners do not realise, i.e. the first layer but if that produces some ridges or troughs then it may take 2 or 3 layers to smooth them out; really by layer 3 you should be looking at a flat surface. However your print looks very thin, so maybe. What is the Z height? What layer height are you using?

Good idea, all part of that learning process 🙂 Lol there is always a danger in recommending on something you know nothing about; thinking it about, with 1.75 you need to move the filament through the system faster to deliver the same volume of filament that you get with 2.85 - so maybe you do need a hotter temperature, aarghh!

OK, nothing like 30 minutes reflection to clear the mind. What we have here is something no-one understands, too many contradictions. If your test this evening does not work I suggest you do the following, going back to square one. Load a different reel of filament; preferably something fairly new so that the filament wind will be loose, rather than a reel that has been significantly used where the inner wind will normally be tighter and can stick. Load Cura and yet again check your filament setting and your printer settings. These are the only settings where Cura interacts with the outside world. We know the stl file for the circular model is fine; @Smithyhas tested it. Load that stl file and regenerate the gcode. Print the gcode Assuming it fails then load the stl file for the rectangular model and generate a new gcode file Print the gcode If If both work then great. If If both fail then you have a hardware or filament problem LLol if one fails and one works we are back to where we are now, not having a clue as to what is happening

This is a pure guess but it could be your retraction settings, i.e. there is a retraction as you move from the square geometry walls to the circular geometry walls. Perhaps you extraction length is too long or your retraction prime speed is too slow. There is another setting "Retracton extra prime amount" which sounds as if it may help - I have never used it.

Hmn pic 2 looks like the entire print not mid print. Do you mean sometimes the problem does not start until mid print and sometimes it is the whole print?