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clfcool

Bad print - deer head

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too many problems

can anyone give a suggestion? Thanks!

0.2 layer height, 20 mm/s print speed, wall 0.9, temperature 190, retraction speed 40, retraction length 7

IMG 4158

IMG 4160

why there are so many rings under ears and back of the neck. and so many strings

 

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What version of Cura are you using? I've seen several cases using recent versions where retraction doesn't trigger correctly when moving between islands over a print - that could be causing the stringing between the top most parts.

What sort of printer are you printing on? They seem to be rather non-ultimaker settings - are you using something else?

 

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I also want to know what version of Cura you have.

Assuming you are using an Ultimaker then you probably have a .4mm nozzle so you need to change the wall to .8 (not .9). Using .9 with nozzle set to .4 will cause problems (like the loops or "rings"). Wall should always be a multiple of actual nozzle size.

The stringing is mostly between support. There may be a bug regarding support in Cura where it relates to retraction - not sure.

There is a new secret beta version of Cura that has better support features. You can try it here:

http://software.ultimaker.com/Cura_closed_beta/

I'd like to see a better picture of the "rings under ears".

 

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i use 13.06.04

my printer is ultimaker based, but the mainboard are produced by a chinese factory,they call it andciv.

 

What version of Cura are you using? I've seen several cases using recent versions where retraction doesn't trigger correctly when moving between islands over a print - that could be causing the stringing between the top most parts.

What sort of printer are you printing on? They seem to be rather non-ultimaker settings - are you using something else?

 

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my nozzle size is 0.3

these are another verion of failed prints

IMG 4188

IMG 4191

IMG 4194

 

 

I also want to know what version of Cura you have.

Assuming you are using an Ultimaker then you probably have a .4mm nozzle so you need to change the wall to .8 (not .9). Using .9 with nozzle set to .4 will cause problems (like the loops or "rings"). Wall should always be a multiple of actual nozzle size.

The stringing is mostly between support. There may be a bug regarding support in Cura where it relates to retraction - not sure.

There is a new secret beta version of Cura that has better support features. You can try it here:

http://software.ultimaker.com/Cura_closed_beta/

I'd like to see a better picture of the "rings under ears".

 

 

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yesterday, i got a backlash issue and still "rings" on the wall and door

mostly, i think the rings are more likely come out from overhang part than vertical wall (i still got rings on vertical wall)

IMG 4450

IMG 4451

 

i havnt use the secret cura yet, i'll give it a try asap.

 

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So many problems...

1) Fan. Do you even have a fan? Some of the problems I see imply that your fan is off or is blowing the wrong direction (sucking). Does it work when you are printing? Do you have a fan? You can get by without a fan if you print slower - especially minimum layer time needs to be something like 7 seconds or higher. But fan can fix 3 of the problems you are having possibly.

2) backlash aka play. The castle looks pretty good but in the top layer I can see that you have two paths/strings close together and then a gap. This pattern repeats. This is classic issue of play. It is caused by loose belts - typically the short belts (those to the motor). Sometimes it is in the head itself - possibly bad bearings or loose parts. Try pushing the head back and forth with power off - before it starts moving there should be very little movement. Looking at your castle top I would say you have .4-.6mm of play in one or both axes.

These aren't your biggest problems.

LOOPS ON WALLS!

What the hell? I have never seen loops on near vertical walls like this - even at 45 degrees there should be zero loops. I have seen many people's "bad" prints and never seen this. Is the head moving out of the part and then suddenly coming back in? I'd have to see it happening in a video.

STRINGING

This can be reduced by using better quality filament e.g. printbl.com and/or lowering your temperature. I'm wondering if your temperature is way off. Try calibrating at 100C. Set head to 100C. Use q tip with water and touch to aluminum block. Then increase or decrease the temp to find what temp your thermostat thinks water boils at. If this is off by 10C then no big deal. If it is off by more then you can fix it in Marlin. We go over that if necessary.

 

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before short belt tension

IMG 4475

after short belt tension

IMG 4477

gaps not that much, still a little, much better

IMG 4479

IMG 4481

after tension, infills are good. there's a problem of the corner, it is higher than the surface.

IMG 4483

IMG 4485

compare between two cubes, left - untensioned(0.2 layer height), right-tensioned(0.1 layer height)

 

bottom

IMG 4486

top

IMG 4487

side

IMG 4488

IMG 4489

the right side cube:

1. top is better than left

2. but bottom lines are thinner

3. corners are not as good as left(i didn't record the difference of the temperature)

 

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Thank you for you diagnostic very much!

1) yes, i have two fans on left and right side of the heating block, each of them is 24v, 0.08a 40mm x 40mm. And they both work when printing.

2) i adjust my belt tension last night. the results are better than before. i test my head when shutting down the machine, it has little movement, almost still.

loops on wall, it happens everywhere, i have no idea about that. maybe i'll record a video later.

stringing, i'll test my temperature tonight and come back to report.

 

So many problems...

1) Fan. Do you even have a fan? Some of the problems I see imply that your fan is off or is blowing the wrong direction (sucking). Does it work when you are printing? Do you have a fan? You can get by without a fan if you print slower - especially minimum layer time needs to be something like 7 seconds or higher. But fan can fix 3 of the problems you are having possibly.

2) backlash aka play. The castle looks pretty good but in the top layer I can see that you have two paths/strings close together and then a gap. This pattern repeats. This is classic issue of play. It is caused by loose belts - typically the short belts (those to the motor). Sometimes it is in the head itself - possibly bad bearings or loose parts. Try pushing the head back and forth with power off - before it starts moving there should be very little movement. Looking at your castle top I would say you have .4-.6mm of play in one or both axes.

These aren't your biggest problems.

LOOPS ON WALLS!

What the hell? I have never seen loops on near vertical walls like this - even at 45 degrees there should be zero loops. I have seen many people's "bad" prints and never seen this. Is the head moving out of the part and then suddenly coming back in? I'd have to see it happening in a video.

STRINGING

This can be reduced by using better quality filament e.g. printbl.com and/or lowering your temperature. I'm wondering if your temperature is way off. Try calibrating at 100C. Set head to 100C. Use q tip with water and touch to aluminum block. Then increase or decrease the temp to find what temp your thermostat thinks water boils at. If this is off by 10C then no big deal. If it is off by more then you can fix it in Marlin. We go over that if necessary.

 

yes! i set 0.3 nozzle size in cura. (sometimes 0.27 to adjust the flow)

 

>my nozzle size is 0.3

Oh. Wow. Did you set that in Cura? The default is .4 so make sure you set that!

 

 

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Well again, most of your stringing is between model and support. I suspect there might be a bug in Cura on that issue. But I don't know. I rarely use support. You can tell by looking at the layer view - if there is retraction it shows a short vertical blue line at the start of the horizontal blue line (blue lines are non-extruding moves).

Here are some tips on stringing:

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/

 

 

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i tested my temperature with water, and the boiling point is about 90c.

and i test with the hollow pyramid, after started printing, i lowered the temperature all way down to test the limitation. the print speed is set at 40. sliced with kisslicer with retraction setting as follows:

; destring_suck = 7

; destring_prime = 7

; destring_min_mm = 0

; destring_trigger_mm = 2

; destring_speed_mm_per_s = 80

; wipe_mm = 0

Hollow_Pyramid_test

 

 

 

when temperature down to 140, my printer dont extrude any filament at all.

and till the lowest temperature, the stringing is always there.

 

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That is HORRIBLE stringing in the pyramid. You need more retraction. What does the "7" mean? does it mean 7mm of plastic out of the nozzle? Does it mean 7mm at the extruder motor? Is it some other unit? The extruder should rotate about 1/3 of the way around on each retraction. Per haps the 80mm/sec is the problem. You shouldn't move the extruder faster than around 25mm/sec. Some UMs can reach 40mm/sec but many can't. 25mm/sec is a reasonable "destring speed".

Also watch the filament in the bowden tube. When extruding it is in the top of the arc. When retraction occurs you can see the filament at the top of the arc lower to the bottom of the bowden tube.

Some filaments never completely stop extruding but I've never seen it as bad as this pyramid! I think the "7" is just the wrong value needed.

See this about temp and stringing and note that below a certain temp, Marlin normally will not move the extruder motor. This is to avoid grinding the filament:

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/

 

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