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dungaav

Printed things are brittle and not smooth/not clean.

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Hello we are newbie in 3d printing and got a few problems while printing some objects, for example an iphone case.

Printed using default "Normal" setting on Cura.

1. Its brittle. some of the layer does not stick to each other.

2. The 1st layer that stick to the printing base are not smooth.

3. The last layer looks like just filled with random things, not smooth.

On cura, its shown that 1st layer are filled to be smooth but on the last layer, it does not create last-smooth-layer.

Zti116W.jpg

The First layer looks filled by random fills on Cura, How to make this first layer filled with smooth fillings?

XQeOfpi.jpg

Last layer are filled by nothing on Cura. I want it to be filled smooth.

21mvN0U.jpg

4. What is this? (see picture)

Picture speaks thousand words, here the photo :D

hvDeSyU.jpg

1YnxRXt.jpg

Thanks

 

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good morning ! :-)

I would first check that your rubber belts are really nice and tight !

Then I would use your ulticontroller and slow the printer down to maybe .. 75.

Then on the ulticontroller, put your temp upto about 220 and see if the flow comes out smoother.

You could also increase your flow to 110 and see if that helps.

Also if you have the new Bertho extruder on the back, make sure the little delrin wheel inside it is moving freely.. that can help screw up prints..

Also the little dots coming out of the side, could be more related to your model than the printer... have you checked the model in the free version of netfabb..?

hope that helps. if not, get back to us and we will set you up !

Ian :-)

 

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The bottom layer is the hardest layer to make it look good. The secret is in "bed levelling". If you want a perfect layer you need perfect levelling. Home z axis only. by hand move the (cold, clean) nozzle over close to each levelling screw. use a piece of paper and slip between nozzle and bed. To get a feel for it loosen until the paper has zero resistance then slowly tighten until you just feel a little bit of resistance. Repeat at all 4 screws then repeat again. Then again. If you want it perfect repeat this procedure until every corner is perfect. It make take 10 tries but it's worth it. Do this at least once per print on a new ultimaker and at least once per day on an older one (the bed shifts like the string on a guitar).

After it's perfect turn each screw 1/8 turn tighter (paper is tighter) to compensate for the width of paper (usually about .1mm).

When you print the skirt it should look perfect it should be flatened. If you have too much space you will get rounded filament (like your picture). If you have not-enough space you will have other problems - for example so thin you can see through the filament and the pressure in nozzle builds up until it suddenly all comes out at once. Or you bumps repeating every 1/4 inch. Don't be afraid to halt after the skirt is done and start over. Better than waiting until entire print is done.

Okay that's the most important thing.

Also:

In addition I think .2mm is the ideal thickness for bottom layer when you want it to look good. .1mm is just too thin and too hard to get the levelling perfect. .3mm is probably fine but that is more for when you don't care about the bottom of your print.

 

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I decided to post the next advice separately - getting levelling perfect is most important.

You appear to have some stringing. I have found that I get slight stringing at temps above 200C and prefer to print at 190C but 190C is very tricky. You also have to print slow if you print at 190C. I'm conflicted here. If you don't have stringing issues (no gaps to span) then 240C comes out much nicer. See my conflict? 190 or 240? 240 also sticks to the blue tape better but you can probably get by with washing the blue tape with alcohol which makes your part stick better so if you have "sticking" issues - only then should you try wiping with cotton swab with rubbing alcohol (aka isopropyl).

But I recommend printing at 190C - try it. See if stringing goes away. Also you need to enable retraction and set minimum retraction distance to .5mm because you have things that are very close together (1 or 2mm apart) and if you don't set this distance very low it will string. Also you should enable retraction for everything to get a perfect first layer - do this in "expert config" "retraction" uncheck "hops only". I've never done this personally but it can clean up the bottom layer. If you print at 190C the plastic will be very thick and your printer will fail unless you print slow due to massive pressure in the nozzle. I would print at 50mm/sec max. First layer even slower - maybe 20mm/sec. Be patient. At 240C you can print 200mm/sec as the plastic will flow like honey.

As far as those bumps on the side of your phone - those are very difficult to fix. They might be the "z seam" which you can't do much about. printing at 190C *might* help. Printing slower might help. Printing hotter mike help. Those side bumps are very tricky and I don't think you should even try to fix those.

You could sand them out carefully and then reshine your print with a heat gun or using THK (the only chemical that seems to dissolve PLA - google THK and PLA if you are interested). Sanding will make the part whiter and duller and less pretty. People use different techniques to fix this including automotive paint or heat. Heat is tricky because you can deform your part so you want high heat briefly to heat only the surface which is obviously tricky. Practice on a failed print.

What is your wall width? You should set that to .4mm (same as nozzle). Did you set your wall width higher? Don't. Not for this part.

 

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I just saw your comment "1st layer no smooth filling".

What is the thickness of those lines in your print?

Cura has a bug called the "thin wall bug". If the width is 1mm and the nozzle is .4 (nozzle should be .4 on ultimaker) then that leaves only .2mm to fill in and Cura thinks it is impossible (it *is* possible). You could fudge this by telling cura your nozzle is .33mm (.33+.33+.33 is about 1mm so will fit) but this causes other problems. Best is to use the newer beta cura if you can get it. It should come out any day now. Or use Kisslicer (reasonably easy to use - similar to cura).

 

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As George noted, I think a lot of your problem is mostly with the 'thin wall' problem that causes Cura to not fully infill small spaces. Making sure that your wall thickness = nozzle width may help with that.

To do that you'll need to enable the normal settings in Cura, not just the 'quickprint' settings, You can then enable retraction as George mentioned.

I think you are also under-extruding a little bit, so that the individual lines that you print don't really merge together into a solid. Make sure that you're extruder drive spring isn't too tight or too loose (the length of my spring is about 11mm - it shouldn't be totally compressed, nor too loose). Also, you need to measure the width of your filament, and use the real size, not the default of 2.89, in order to ensure that the slicer requests enough plastic to make the printed lines be the right size.

 

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good morning ! :smile:

I would first check that your rubber belts are really nice and tight !

Then I would use your ulticontroller and slow the printer down to maybe .. 75.

Then on the ulticontroller, put your temp upto about 220 and see if the flow comes out smoother.

You could also increase your flow to 110 and see if that helps.

Also if you have the new Bertho extruder on the back, make sure the little delrin wheel inside it is moving freely.. that can help screw up prints..

Also the little dots coming out of the side, could be more related to your model than the printer... have you checked the model in the free version of netfabb..?

hope that helps. if not, get back to us and we will set you up !

Ian :smile:

 

My environtment temperature constantly about 30~33 Celcius degree, and I use the default setting on ulticontroler 220 celcius degree, and my speed is average on normal printer on Cura, I ll check my speed latter. I found an Issue about a slightly un straight iron that connect wood clamp for the belt. Is this one can be the issue??

 

The bottom layer is the hardest layer to make it look good. The secret is in "bed levelling". If you want a perfect layer you need perfect levelling. Home z axis only. by hand move the (cold, clean) nozzle over close to each levelling screw. use a piece of paper and slip between nozzle and bed. To get a feel for it loosen until the paper has zero resistance then slowly tighten until you just feel a little bit of resistance. Repeat at all 4 screws then repeat again. Then again. If you want it perfect repeat this procedure until every corner is perfect. It make take 10 tries but it's worth it. Do this at least once per print on a new ultimaker and at least once per day on an older one (the bed shifts like the string on a guitar).

After it's perfect turn each screw 1/8 turn tighter (paper is tighter) to compensate for the width of paper (usually about .1mm).

When you print the skirt it should look perfect it should be flatened. If you have too much space you will get rounded filament (like your picture). If you have not-enough space you will have other problems - for example so thin you can see through the filament and the pressure in nozzle builds up until it suddenly all comes out at once. Or you bumps repeating every 1/4 inch. Don't be afraid to halt after the skirt is done and start over. Better than waiting until entire print is done.

Okay that's the most important thing.

Also:

In addition I think .2mm is the ideal thickness for bottom layer when you want it to look good. .1mm is just too thin and too hard to get the levelling perfect. .3mm is probably fine but that is more for when you don't care about the bottom of your print.

 

I already measuring the bed level using papper, I use kind of envelop to do this actually I quiet satisfy for bottom layer, that not my main issue tho, the thing is the side after the bottom layer (picture number 4). And I also always do bed leveling before printing, am I suppose to do this?? because every time I finished printing I remove the tape because its wreck.

 

I decided to post the next advice separately - getting levelling perfect is most important.

You appear to have some stringing. I have found that I get slight stringing at temps above 200C and prefer to print at 190C but 190C is very tricky. You also have to print slow if you print at 190C. I'm conflicted here. If you don't have stringing issues (no gaps to span) then 240C comes out much nicer. See my conflict? 190 or 240? 240 also sticks to the blue tape better but you can probably get by with washing the blue tape with alcohol which makes your part stick better so if you have "sticking" issues - only then should you try wiping with cotton swab with rubbing alcohol (aka isopropyl).

But I recommend printing at 190C - try it. See if stringing goes away. Also you need to enable retraction and set minimum retraction distance to .5mm because you have things that are very close together (1 or 2mm apart) and if you don't set this distance very low it will string. Also you should enable retraction for everything to get a perfect first layer - do this in "expert config" "retraction" uncheck "hops only". I've never done this personally but it can clean up the bottom layer. If you print at 190C the plastic will be very thick and your printer will fail unless you print slow due to massive pressure in the nozzle. I would print at 50mm/sec max. First layer even slower - maybe 20mm/sec. Be patient. At 240C you can print 200mm/sec as the plastic will flow like honey.

As far as those bumps on the side of your phone - those are very difficult to fix. They might be the "z seam" which you can't do much about. printing at 190C *might* help. Printing slower might help. Printing hotter mike help. Those side bumps are very tricky and I don't think you should even try to fix those.

You could sand them out carefully and then reshine your print with a heat gun or using THK (the only chemical that seems to dissolve PLA - google THK and PLA if you are interested). Sanding will make the part whiter and duller and less pretty. People use different techniques to fix this including automotive paint or heat. Heat is tricky because you can deform your part so you want high heat briefly to heat only the surface which is obviously tricky. Practice on a failed print.

What is your wall width? You should set that to .4mm (same as nozzle). Did you set your wall width higher? Don't. Not for this part.

 

Wow, this one is looks promising, but my logic say I already print with 220C and the layer not sticking enough, I will try to print with slower speed, tho. But In earlier test I got good output with default setting, and your advise for keep practicing I will do that, but now my main Issue is because iron for connecting the wood belt clamp is in slightly unstraight. I recognize it as I did unassembled and when I anssambled it again as I rotate the dynamo its look like my belt clamp waving, I compare it with another iron and the another iron not have that Issue, I dunno why I got the slightly unstraight part, I dissapointed :( and could it be the main issue for my alwayd unperfect printing issue??

Btw, thax for replying

 

I just saw your comment "1st layer no smooth filling".

What is the thickness of those lines in your print?

Cura has a bug called the "thin wall bug". If the width is 1mm and the nozzle is .4 (nozzle should be .4 on ultimaker) then that leaves only .2mm to fill in and Cura thinks it is impossible (it *is* possible). You could fudge this by telling cura your nozzle is .33mm (.33+.33+.33 is about 1mm so will fit) but this causes other problems. Best is to use the newer beta cura if you can get it. It should come out any day now. Or use Kisslicer (reasonably easy to use - similar to cura).

 

This is new for me, and I will try this as I knew that Ultimaker is the most accurate afordable 3Dprinter out there :), And on my model the wall is not that thin, I am not in that detail printing yet my wall thick is default and the thinnest part ofmy model width is just 5mm, Also the new beta Cura not solving my Issue on filling the layer on the back of bottom layer (picture number 4) thax for gimme knowledge and helping :)

 

Good news, dunga - the cura beta is now available:

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

I'm told it fixes thin wall issues which was one of your issues.

 

Yeah, thax for the information, I already downloded it and use that, but how could I fill my layer on the back off the bottom layer (please see the 4th pict), in new Cura beta you mention above, still, I cant figure it out how to fill the layer. And also I have slightly unstraight iron part for wood belt clamp, could it be the issue why I couldn't do perfect printing?

 

As George noted, I think a lot of your problem is mostly with the 'thin wall' problem that causes Cura to not fully infill small spaces. Making sure that your wall thickness = nozzle width may help with that.

To do that you'll need to enable the normal settings in Cura, not just the 'quickprint' settings, You can then enable retraction as George mentioned.

I think you are also under-extruding a little bit, so that the individual lines that you print don't really merge together into a solid. Make sure that you're extruder drive spring isn't too tight or too loose (the length of my spring is about 11mm - it shouldn't be totally compressed, nor too loose). Also, you need to measure the width of your filament, and use the real size, not the default of 2.89, in order to ensure that the slicer requests enough plastic to make the printed lines be the right size.

 

Next time I will do print with expert setting in cura and also do the slowest print like been mentioned above :), but I just find out that one of my iron part for connecting wood belt clamp not in fully straight possition, could it make my print result unperfect? I dunno why ultimaker sent me this slightly unstraight iron part

Regards,

DungaAV

 

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