Skeinforge..."waves" happen on flat surface print over past 4 months

Hello All,

This is my first post on this forum, I'm glad I found this place and willing to join the group.

Okay...I have a FF CreatorX and using Skeinforge+ReplicatorG for slicing
I started printing this piece 4 months ago, about 210x100 mm
however the "waving" unflatness keep happening on where it suppose to be completely flat (plz see attach images, focus on the red circle I drew)
I met a FF engineer and he suggests that I should change Edge Width over Height under Carve to 2.4.
Although the change did brought me 2 successful prints without the wave from over 30 failures ...
today the strange things happen again and I didn't change any setting from last success at all!

I use PLA, print temp 200,
no matter how I change the temp for both extruder or hot bed, the waving still there.
whats more, they happened almost on the same spot over prints and prints!

Edited 1 time(s). Last edit at 02/24/2015 07:53PM by tutu7931.

Please don't double post!

---

Bob Morrison
Wörth am Rhein, Germany
"Luke, use the source!"
BLOG - PHOTOS - Thingiverse

It's not possible that this is a belt vibration that occurs in the same place each time? I would expect this to be caused by some sort of oscillation but I don't have experience with your machine.

---

http://www.marinusdebeer.nl/

The reason the FF engineer had you change those settings may have been to fix an over extruding issue.
Does this issue continue further up on taller prints?
Is it with 100% infill? Does it go away with less than 100% infill?
Have you tried a different slicing program?
Have you measured your filament for consistent diameter? Are you using a different roll of filament since your last successful print?

I don't have your machine, but I had this problem when my hot end was too close to the print surface. My first layer was set to .2mm and may have been printing a layer of .1mm (or less). When the layer moved up .3mm (layer height) it would have only been .4mm instead of .5mm. After about 5-7 layers like this the volume slowly fixed itself. This also created swell on the perimeters making a bell curve along the sides.

All thanks for your reply,

Ohmarinus I've tighten up the belt but still..

KingRahl,
> my print model is 210x100x0.8mm so when skeinforge slices it the outcome is 4 layers and 100% infill.
> Sometimes the "wave" starts on 1st layer already, and sometimes it starts to happen on 2nd (which is when it starts doing the horizontal infill).
> I've tried slic3r, the surface is smoother I think is because the slic3r infill goes 45 degree direction, however the rest of my model after 4th layer has a lot of 0.6mm columns which slic3r just automatically delete them (no thin wall detect) and that's why I move back to skeinforge.
> Yes, I have measured the filament and the diameter usually 1.73-1.77 so I just use 1.75. And yet I use the same filiament for all these prints, Though I did tried using different filament, but still and what dry me more crazy is the "wave" almost happen on the same spot on every print!

Quote

> Yes, I have measured the filament and the diameter usually 1.73-1.77 so I just use 1.75. And yet I use the same filiament for all these prints,

This is likely to be the problem.

.04 mm difference can cause this already!

I would try a different filament to see if it improves. Also check if the temperature really is stable during prints.

---

http://www.marinusdebeer.nl/

Quote
tutu7931
> Sometimes the "wave" starts on 1st layer already, and sometimes it starts to happen on 2nd (which is when it starts doing the horizontal infill).

It's all a volume issue then. Too much is being laid down for each layer. Remove the hot end from the extruder and extrude 100mm using your software. Measure with calipers. If it comes out as 100mm, your firmware is properly calibrated. Next, recalibrate your distance to the bed. Finally, make sure you program your config. settings in Skeinforge to match nozzle size, filament size, edge width over height and anything else you may have been told. I don't use Skeinforge so I don't know if it will automatically save your settings. If not then save those and make sure they are loaded each time you use it.

Quote
Ohmarinus

Quote

> Yes, I have measured the filament and the diameter usually 1.73-1.77 so I just use 1.75. And yet I use the same filiament for all these prints,

This is likely to be the problem.

.04 mm difference can cause this already!

I would try a different filament to see if it improves. Also check if the temperature really is stable during prints.

But it doesn't explain why the wave always happen on same spot.

KingRahl is right. Too much fimament is being laid down and it starts overlapping causes little bulges that look like waves when next to each other.

Why? Well, either the filament is smaller than you set in the machine (as already suggested) or the Esteps has not been calibrated, or you need to compensate for it using Extrusion Multiplier and putting smaller than 1 like 0.85.

I fought with this same thing my first year of printing.