<![CDATA[SoliForum - 3D Printing Community — filament layers come apart on inside of circle]]> 2015-04-30T15:20:46Z PunBB https://www.soliforum.com/topic/10957/filament-layers-come-apart-on-inside-of-circle/ <![CDATA[Re: filament layers come apart on inside of circle]]> I think you have a mechanical backlash/slop issue. From your picture, I notice a few things:

http://soliforum.com/i/?l6CKE7B.jpg

1. Your X motor appears to be mounted incorrectly. If it is not flush with the lawsy carriage, it will wobble, resulting in backlash on your X axis.
2. Your error is not consistent around the circle, but if we draw a line through the circle, we almost get perfect symmetry between the sloppy areas and the areas of perfection.

Check your belts and ensure everything is rigid. Any movement beyond what the motors call for is a bad thing. Most likely, your X motor is loose, and your hotend has some slop as well.

Speed isn't really a problem. I can print something like this at 100mm/s with my fan turned on (or enclosure off). A lot of the issues you are experiencing went away when I switched my SD4 to a direct drive system where the Y motor moves the shaft via a coupler.

]]> https://www.soliforum.com/user/7321/ 2015-04-30T15:20:46Z https://www.soliforum.com/post/94509/#p94509 <![CDATA[Re: filament layers come apart on inside of circle]]> Agreed with others.  Go slower and check temps.  Also, make sure your extrusion width is at lease 1.2x your nozzle diameter.  It needs a little bit of squish to bond to the adjacent layer, in my experience.  This is one of the harder problems to get exactly right.  Thankfully it is inconsequential on most prints.

]]> https://www.soliforum.com/user/4377/ 2015-04-30T13:22:09Z https://www.soliforum.com/post/94496/#p94496 <![CDATA[Re: filament layers come apart on inside of circle]]> Slow down the speed on your perimeters slightly

]]> https://www.soliforum.com/user/7171/ 2015-04-30T12:45:03Z https://www.soliforum.com/post/94495/#p94495 <![CDATA[Re: filament layers come apart on inside of circle]]> I've calibrated with this brand, but not this particular filament.  Maybe it's time to do that again!

]]> https://www.soliforum.com/user/211/ 2015-04-30T12:43:53Z https://www.soliforum.com/post/94494/#p94494 <![CDATA[Re: filament layers come apart on inside of circle]]> have you done a proper temperature calibration for the material you are using? a tall, single wall cube with temp changes every 10mm or so to determine what works best for that particular roll of filament... too cold & it will show cracking or peel apart easily, too hot & it will show bubbles (and often break/crack easily)... 
I usually start out with 5 degree temp changes, then narrow it down further by doing again with 1-2 degree temp changes to find the ideal setting.

I have found that the ideal temp can vary from one roll to another even with the same type of plastic. doing a temp calibration is now a regular part of my calibration routine when changing rolls. I keep a record of what works best for each roll I have - feed steps/mm, extrusion multiplier, & temp calibration. (I have 6 rolls of PLA in various colors, and 4 rolls of ABS in various colors - each one has different settings)

and yeah, as carl said - speed matters, too.

]]> https://www.soliforum.com/user/10399/ 2015-04-30T12:40:24Z https://www.soliforum.com/post/94492/#p94492 <![CDATA[Re: filament layers come apart on inside of circle]]> Yeah, I tend to print as cool as I can because I have burnt out a few heating resistors, and I hate having down time.  I'll wait and see what other comments we get here, and then try increasing temp on some test prints.

]]> https://www.soliforum.com/user/211/ 2015-04-30T12:29:26Z https://www.soliforum.com/post/94490/#p94490 <![CDATA[Re: filament layers come apart on inside of circle]]> 205 seems kinda low, but I an stil noob in this matters. Maybe the "veterans" should try to answer this.

]]> https://www.soliforum.com/user/6822/ 2015-04-30T11:52:42Z https://www.soliforum.com/post/94487/#p94487 <![CDATA[Re: filament layers come apart on inside of circle]]> 205 degrees, but I think my hot end is non-stock (aluminum block with resistor in it), so the temp might not be comparable to a different printer.  Anyway, you suggest trying hotter?

]]> https://www.soliforum.com/user/211/ 2015-04-30T11:18:27Z https://www.soliforum.com/post/94486/#p94486 <![CDATA[Re: filament layers come apart on inside of circle]]> What temp are you printing at ? Do you hear thumping noises in the extruder ?

]]> https://www.soliforum.com/user/6822/ 2015-04-30T10:10:49Z https://www.soliforum.com/post/94482/#p94482 <![CDATA[Re: filament layers come apart on inside of circle]]> Might try that, although I expect I'm already printing fairly slowly; never been a racer.  Could it be anything else, like extruder temp, or the amount it squeezes out?

]]> https://www.soliforum.com/user/211/ 2015-04-30T01:00:52Z https://www.soliforum.com/post/94463/#p94463 <![CDATA[Re: filament layers come apart on inside of circle]]> driggers wrote:

Lately when I print circles, the filament sometimes does not stick to the last layer (see picture).  How do I fix this?

http://soliforum.com/i/?WI6bcfk.jpg


Slow down. Think of a string of hot plastic like a rubber band. If you stretch around a bend real fast then it will pull away from the bend as it cools. If you slow down then it will cool more as it is placed which will allow it to stick better. Depending on your software if it allows do inside perimeters at 25 or so.

]]> https://www.soliforum.com/user/7731/ 2015-04-30T00:47:22Z https://www.soliforum.com/post/94462/#p94462 <![CDATA[filament layers come apart on inside of circle]]> Lately when I print circles, the filament sometimes does not stick to the last layer (see picture).  How do I fix this?

http://soliforum.com/i/?WI6bcfk.jpg

]]> https://www.soliforum.com/user/211/ 2015-04-30T00:28:36Z https://www.soliforum.com/post/94461/#p94461