Very odd printing problems Hi all I have a pretty modified Monoprice maker select. Its running on a ramps board with the repetier firmware. I have been printing happily through many many spools of filament (mainly ABS). I recently had some issues where my extruder would underextrude randomly through the print, mainly larger prints. After much faffing around, I replaced the whole hot end with a china special. Works well enough, after calibrating it etc, I can print a pretty good benchy: 20161211211032.jpg mod_embed_images_loadimage('88242591e5f6413bfc7275a08d276bad', '/forum/thumbcache/4fc/163/e45/0dc/511/26a/3ec/597/49e/ccc/6a_800x400.png', 'http://fotifixes.com/imagehosting/images/2016/12/12/20161211211032.jpg', 'https://reprap.org/forum/addon.php?262,module=embed_images,check_scaling=1,url=http%3A%2F%2Ffotifixes.com%2Fimagehosting%2Fimages%2F2016%2F12%2F12%2F20161211211032.jpg', '', 729876, 800, 400, 'Loading image ...', false); I was messing with the flow rate, so ignore the under extruded section at the bottom :) The issue comes when I try and print a large round object (jack stand adapter). I have successfully printed this on the old hot end (before the issues). I attempted to re-print the exact same g code on this new hot end and I get odd issues. I get bobbly outer edges and bubbles showing, the print head ends up rumbling over these imperfections and it gets worse and worse until I cancel the print. 20161211210940.jpg mod_embed_images_loadimage('743fade86901e545ebb49a22fdfcebfd', '/forum/thumbcache/887/7c8/ca8/25a/139/ce8/b81/276/e93/74e/91_800x400.png', 'http://fotifixes.com/imagehosting/images/2016/12/12/20161211210940.jpg', 'https://reprap.org/forum/addon.php?262,module=embed_images,check_scaling=1,url=http%3A%2F%2Ffotifixes.com%2Fimagehosting%2Fimages%2F2016%2F12%2F12%2F20161211210940.jpg', '', 729876, 800, 400, 'Loading image ...', false); 20161211214056.jpg mod_embed_images_loadimage('dc6adf222828127385fefd625783dd0a', '/forum/thumbcache/37f/d35/132/2ac/95d/2ab/a4f/742/f43/d44/f3_800x400.png', 'http://fotifixes.com/imagehosting/images/2016/12/12/20161211214056.jpg', 'https://reprap.org/forum/addon.php?262,module=embed_images,check_scaling=1,url=http%3A%2F%2Ffotifixes.com%2Fimagehosting%2Fimages%2F2016%2F12%2F12%2F20161211214056.jpg', '', 729876, 800, 400, 'Loading image ...', false); 20161211214138.jpg mod_embed_images_loadimage('21cd303d8faeedf1eeccebbf656976b9', '/forum/thumbcache/871/87e/04d/296/6f1/50b/865/b8b/9f3/eff/f3_800x400.png', 'http://fotifixes.com/imagehosting/images/2016/12/12/20161211214138.jpg', 'https://reprap.org/forum/addon.php?262,module=embed_images,check_scaling=1,url=http%3A%2F%2Ffotifixes.com%2Fimagehosting%2Fimages%2F2016%2F12%2F12%2F20161211214138.jpg', '', 729876, 800, 400, 'Loading image ...', false); You can see where it starts off OK and then ends up mangling it self. I have also figured out that its only affecting solid inlif models (which I had no issue printing before). I printed a 100mm rectangle with 36 solid layers and then 10% infill from then on, you can see the issue: 20161212084235.jpg mod_embed_images_loadimage('bfa86b074274a0fa2097af6e49eb05a2', '/forum/thumbcache/b81/108/29a/36b/154/ccd/394/73f/f14/24b/40_800x400.png', 'http://fotifixes.com/imagehosting/images/2016/12/12/20161212084235.jpg', 'https://reprap.org/forum/addon.php?262,module=embed_images,check_scaling=1,url=http%3A%2F%2Ffotifixes.com%2Fimagehosting%2Fimages%2F2016%2F12%2F12%2F20161212084235.jpg', '', 729876, 800, 400, 'Loading image ...', false); Not quite sure where to go from here. This printer has printed this model perfectly before. Benchy printed on my normal settings straight off, without any changes. I am using simplify3d with a set of profiles I have honed down for various end results. Any thoughts are much appreciated. https://reprap.org/forum/read.php?262,729876,729876#msg-729876 Sat, 12 Sep 2026 07:25:04 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?262,729876,735520#msg-735520 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,735520#msg-735520 Looks like the new nozzle is "taller". Can't tell if the across flats is smaller but it looks it.
If the tip is further from the heater and/or the across flats is smaller then it will run cooler at the outlet. Try bumping the temperature up a bit?
Is your infill speed higher than your perimeter speed? If so this may contribute to why the infill is having an affect.
Is it a 0.4 nozzle and your line width on auto or less than 0.48.]]> MCcarman Printing Wed, 04 Jan 2017 07:51:38 -0500 https://reprap.org/forum/read.php?262,729876,735302#msg-735302 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,735302#msg-735302
Quote
MCcarman
Some thoughts:-

You make a good observation there, and I think might be near to the issue.

Here is the old nozzle:





New nozzle:




As you can see, the older nozzle is wider and flatter.

Reducing the overall extrusion rate to 92% did not make a difference to the issue. I flipped the Z rods, which also made no difference.

I will try reducing the infill rate only to 90/95% and report back.
]]> alexanderfitu Printing Tue, 03 Jan 2017 13:33:07 -0500 https://reprap.org/forum/read.php?262,729876,735262#msg-735262 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,735262#msg-735262 Presumably your new hot end has a different nozzle.
Might be worth a close look at the flat area. Do you have a fixed width for your print width and is it more than 20% larger than the nozzle.
You could be trying to print widths wider than the flat area of the nozzle which will cause it to print a V groove that the next layer bounces over. I am thinking this is probably more pronounced on infill as we tend to specify non concentric patterns.
It wont actually bounce but every high spot restricts flow which builds pressure then the groove provides a bigger gap and the pressure is relieved with a large blob due to local over extrusion.
Reducing the infill will allow the filament to flow side ways and reduce the build up.
Also if the nozzle is not square to the bed or has a burr I assume we could get the same effect but without the extrusion width being relevant.
1.5mm height could be a result of the temperature of the previous layer. The colder the previous layer the more solid it will be so the ruts would be permanent as opposed to a hot a layer that can have the ruts smeared down.]]> MCcarman Printing Tue, 03 Jan 2017 11:10:57 -0500 https://reprap.org/forum/read.php?262,729876,734238#msg-734238 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734238#msg-734238 obewan Printing Fri, 30 Dec 2016 16:36:01 -0500 https://reprap.org/forum/read.php?262,729876,734200#msg-734200 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734200#msg-734200 JamesK Printing Fri, 30 Dec 2016 14:58:40 -0500 https://reprap.org/forum/read.php?262,729876,734196#msg-734196 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734196#msg-734196
Quote
JamesK
Quote
obewan
When you say 'solid' infill, is that 100% infill,
Have you tried reducing to say, 95%.

Yes, sounds like over-extrusion to me, and on the 100% fill layers the only place for the excess to go is out the sides.

Alexander, have you done the fine extruder calibration as described on the following page: [reprap.org]

Interesting. I have done this when I replaced the extruder and hot end (recently)]]> alexanderfitu Printing Fri, 30 Dec 2016 14:50:38 -0500 https://reprap.org/forum/read.php?262,729876,734193#msg-734193 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734193#msg-734193
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obewan
When you say 'solid' infill, is that 100% infill,
Have you tried reducing to say, 95%.

Yes 100%. The odd thing is, I have been able to print this model with 100%infill previously.

Are you saying reduce the flow rate to 95% or just the infill percentage?]]> alexanderfitu Printing Fri, 30 Dec 2016 14:48:45 -0500 https://reprap.org/forum/read.php?262,729876,734192#msg-734192 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734192#msg-734192
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anvoice
Z axis not moving far enough doesn't explain why the center section turns out ok, or why your 40mm high solid cylinder doesn't fail. You could check for that though, at least partially, by (1) measuring the height of your objects with calipers to make sure they aren't too short or (2) taping a pencil to your extruder horizontally and drawing a line on a vertical object with a piece of paper glued to it, then measuring the length of the line and comparing to the distance you told it to move. That would give indication whether you might indeed be missing steps, unless it corrects itself which seems unlikely.

Did you try changing layer thickness? Perhaps with thicker layers you can ascertain whether it's the head dragging.

Another thing I'd try is building a calibration tower (something like a 20x20mm thin wall square) next to your print.

True.

As I have 2 Z motors, I had a thought that one was going out ever so slightly.

A 40mm calibration cube prints nearly spot on (+- 0.2mm).

I havent tried a calibration tower on the same print, good idea.]]> alexanderfitu Printing Fri, 30 Dec 2016 14:47:34 -0500 https://reprap.org/forum/read.php?262,729876,734126#msg-734126 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734126#msg-734126
Quote
obewan
When you say 'solid' infill, is that 100% infill,
Have you tried reducing to say, 95%.

Yes, sounds like over-extrusion to me, and on the 100% fill layers the only place for the excess to go is out the sides.

Alexander, have you done the fine extruder calibration as described on the following page: [reprap.org]]]> JamesK Printing Fri, 30 Dec 2016 10:23:49 -0500 https://reprap.org/forum/read.php?262,729876,734062#msg-734062 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734062#msg-734062 Have you tried reducing to say, 95%.]]> obewan Printing Fri, 30 Dec 2016 07:07:02 -0500 https://reprap.org/forum/read.php?262,729876,734054#msg-734054 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734054#msg-734054
Did you try changing layer thickness? Perhaps with thicker layers you can ascertain whether it's the head dragging.

Another thing I'd try is building a calibration tower (something like a 20x20mm thin wall square) next to your print.]]> anvoice Printing Fri, 30 Dec 2016 06:43:47 -0500 https://reprap.org/forum/read.php?262,729876,734033#msg-734033 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734033#msg-734033
Yes, I have the same issues with 3 different types of filament (see the black and gold) I also have a green colour change that has the same issue.

Surely if it where heatcreap, it would look like underextrusion? To me, it looks like the Z axis isnt moving far enough and the print head is dragging on the print...... A calibration cube prints with the right dimensions though...]]> alexanderfitu Printing Fri, 30 Dec 2016 05:15:57 -0500 https://reprap.org/forum/read.php?262,729876,734031#msg-734031 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734031#msg-734031
Also, did you try a different filament just to make sure it's not a bad spool?]]> anvoice Printing Fri, 30 Dec 2016 05:12:34 -0500 https://reprap.org/forum/read.php?262,729876,734022#msg-734022 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,734022#msg-734022
Tried slow it right down. Makes no difference. The filament is being fed consistently, no issues with that.

I have also, installed a glass bed, no difference.
New bearings on all rods, no difference
new stepper driver on the Z motors, no difference.

I can print a calibration circle (entire bed width) without issue.

I can also print a 30mmx40mm high solid cylinder, without the same thing happening.

Its almost like the Z axis is missing steps randomly as it always starts at 1.5mm +

Cant think of what it is, tearing my hair out!]]> alexanderfitu Printing Fri, 30 Dec 2016 04:50:00 -0500 https://reprap.org/forum/read.php?262,729876,730093#msg-730093 Re: Very odd printing problems https://reprap.org/forum/read.php?262,729876,730093#msg-730093 ggherbaz Printing Mon, 12 Dec 2016 18:55:47 -0500 https://reprap.org/forum/read.php?262,729876,729876#msg-729876 Very odd printing problems https://reprap.org/forum/read.php?262,729876,729876#msg-729876
I have a pretty modified Monoprice maker select. Its running on a ramps board with the repetier firmware. I have been printing happily through many many spools of filament (mainly ABS).

I recently had some issues where my extruder would underextrude randomly through the print, mainly larger prints. After much faffing around, I replaced the whole hot end with a china special. Works well enough, after calibrating it etc, I can print a pretty good benchy:



I was messing with the flow rate, so ignore the under extruded section at the bottom :)

The issue comes when I try and print a large round object (jack stand adapter). I have successfully printed this on the old hot end (before the issues). I attempted to re-print the exact same g code on this new hot end and I get odd issues. I get bobbly outer edges and bubbles showing, the print head ends up rumbling over these imperfections and it gets worse and worse until I cancel the print.







You can see where it starts off OK and then ends up mangling it self.

I have also figured out that its only affecting solid inlif models (which I had no issue printing before).

I printed a 100mm rectangle with 36 solid layers and then 10% infill from then on, you can see the issue:



Not quite sure where to go from here. This printer has printed this model perfectly before. Benchy printed on my normal settings straight off, without any changes. I am using simplify3d with a set of profiles I have honed down for various end results.

Any thoughts are much appreciated.
]]> alexanderfitu Printing Mon, 12 Dec 2016 03:44:37 -0500