Which setting for smooth layers?

Hi.

I'm using Slic3r version 1.1.7, and Pronterface.

Which setting, or what do I have to do to go from this:

to this:


The dimensions are different, but I'd like to have the smooth surface.

Currently the extruder is at 250C and the bed around 110C

- nerdegutta

Try 225c or 230c
That and it looks like you might be overextruding.
What is your perimeter speed set at? Depending on the size of the part id run it as slow as 40mm/sec.

I second the over extruding.

Have adjusted extrution_width to 0.21, was 0.42.
Peremiter_speed is set to 30.
Nozzle height is measured to 0.29mm (0.012"), from the bed when printing starts.

ABS is 1.75, extruder is 0.35.

Nozzle is too far from built plate, you need 0.1 mm. 0.29 is too much. 0.42 width for a .35 nozzle is correct, a 0.21 will give you more problems. Check your steps per mm of your extruder, be sure that when you ask for 10mm extrusion your filament moves 10mm.

I've done some more adjustments:

extrusion_multiplier = 1
extruder_width = 0.42
first_layer_height = 0.30625 (I saw somewhere that this would work good with M8 rod on Z-axis)
layer_height = 0.29375 (Same page as above)


I want the quality of the ring on the left, but I get the one on the right. Big step forward considering the above picture.


Nozzle height on startup is close to nothing about 0.15mm

- nerdegutta

Edited 1 time(s). Last edit at 10/13/2014 03:24PM by nerdegutta.

what type of printer are you using? Looks like you may have some Z-wobble.

Few things:
0.15 still little high but maybe acceptable, I normally used 0.102.
0.3 for first layer is risky if your built plate is not 100% leveled, you need to squeeze filament into the built plate to secure the part, preventing curls and warps that will affect the rest of the print..
Do a dry test print of the part and set it slowly. See if your steppers vibrates, and pay attention to you Z axis for wobbling.
Did you checked the steps per mm of your extruder? Are your extruding the correct amount? One thing is the extruder multiplier and another one is steps per mm on marlin firmware.
The part that looks really nice looks like it had a bath of acetone vapor making it really smooth. Or it was printed at 0.1 layer hight.
Your outer seem line looks straight but the inner one is not, check your printer belts.
One last thing, what percentage of infill are you using? 50 to 100%? Try to lowered as much as possible 5 to 10% and then print it again. Your over extrusion with a high infill percentage may be part of the problem.

Sorry, one last thing. Lower your temperature, you are printing too hot.
And maybe the lights on the picture are deceiving me but looks like the temperature is fluctuating between layers? You have darker segments and the light ones. That can results in awful prints.

My printer is basically homebuilt. At least the mechanical parts. Bought some parts here and there, but...

The steppers, stepper controller, hotend and hotbed is bought from Charlie's 3D Technologies.

X and Y are belt driven, Z is M8 rod. It may not be 110% straight. I might change it to a M10. And recalibrate the steps for that motor.

I've checked the steps on the extruder, and they are OK.

infill_density = 5%

I'll try top lower the temperature to 230C

The perfect part is printed on a USD 38 550,00 machine. Those settings I have no clue about.

Mine is about USD 380,00.

Thanks for good reply. I'll lower the temp, and I'll lower the first layer.


- nerdegutta

One thing that might be important too, did you designed the part or did you downloaded from somewhere? What software did you or the person that designed used? If the original STL file has issues your slicer will translate those issues into your printed part.

If you give me the dimensions I can do a new stl for you and you can test it to see if improve.

I drew it in FreeCad, and exported it as a Mesh formats (*.stl, *.ast...)

Dimensions are as follows.

Inner diameter = 28,25
Outer diameter = 30,25
Height = 20
Knob width = 8
Knob height = 2

All numbers are in mm.

Thanks!

My *.stl is attached.


- nerdgutta

Edited 1 time(s). Last edit at 10/14/2014 12:05PM by nerdegutta.

I don't see any issues with your .stl file.

If you've got Z-wobble, you'll never get a smooth print. Can you post a pic or two of your Z motors, rods, and couplers?

Edited 2 time(s). Last edit at 10/14/2014 12:23PM by Dirty Steve.

Quote
Dirty Steve
I don't see any issues with your .stl file.

That's great.

I have one stepper for the Z-axis, lifting the extruder. The coupling between the motor and the rod is a piece of tube, with the correct inside diameter. I see now that the motor is slightly off in the X-way.

I will need to fix that before I complain about anything else.

Thanks for your time.

- nerdegutta

I have top mounted Z motors with thick rubber washers and solid printed couplers. I have my motors loosely tightened down so that the motor itself can wobble a little, which greatly reduces Z-wobble in the print. Took me months to get rid of my wobble completely.

Is the end of your threaded rod away from the motor in a retainer bearing or anything? Less wobble also if you let the end of the threaded rod move around freely.

Ok, few questions:

The STL file you sent me was the one for the smaller part?
The dimensions you gave me end up in a thinner part, so I assumed was radius instead of diameter?
the top part, you mention 2mm but original STL looks taller?
Original STL shows 4 knobs, while the taller one in your photo have only 3?

Any way, here it is the file I made with Inventor (3 knobs instead of 4)
If it needs any modification let me know.

I might be wrong, but either you attached a different file, or i'm getting crazy ; D

If you look at the image I attached, you might be able to see what I was talking about the imperfections on some STL files, if you look at the base of the original file and you compared with the one I generated you can see the difference in smoothness, also the way that the circles are made is completely different. sure enough it is not the reason of your problems, but definitely reduce quality and smoothness.

Quote
ggherbaz
I might be wrong, but either you attached a different file, or i'm getting crazy ; D

My bad, I attached the wrong file. The dimensions are correct, and the test.jpg image shows what I want. You made it right. Thanks.

My Z-axis is not "open ended". It has a ball bearing in the bottom. I'll remove later today. And do a new print.

Do Inventer come in a freeware/shareware version?

Thanks!

- nerdegutta

It's not free.. Very expensive. Unless you are an student and request an student license, you will have to pay big bucks for it, or like me that happens to have a good friend that let me use his.

Quote
ggherbaz
It's not free.. Very expensive. Unless you are an student and request an student license, you will have to pay big bucks for it, or like me that happens to have a good friend that let me use his.

That's what I thought...

- nerdegutta

I've done some mechanical adjustments. The ball baring in the bottom/the most far away from the motor, is removed. That allowed the rod to wobble just a tiny bit. The images are print 9 and 10 of the _33x20.stl file. Before and after I removed the ball baring. Sliced with Slic3r 1.1.7

I think this result is acceptable.

Thanks for all the help.

(Too bad Invetor cost a sh**load of dollars)




- nerdegutta

Definitely looking better!

The slight inward curve just above the bottom of your prints can be reduced by dropping your bed temperature to around 80C after your first layer. I print ABS with hairspray on glass at a constant 80C for the whole print.

Edited 3 time(s). Last edit at 10/15/2014 10:34PM by Dirty Steve.