Ultimaker v1 quality of print.

[andreasgkertsos 0]

Hello there friends,

I recently bought an Ultimaker 3D printer after a lot of search on google.

I knew from the very beginning that 3D printing is something that needs a loooooot of time to master (if it can be mastered).

I am currently working as an industrial Designer in Athens Greece and i have some complex models in my library to print.

I started printing some models and i am having a hard time understanding all the parameters of the CURA menu.

First of all, the parameters i used for printing these models are 55mm/s printing speed, 202oC nozzle temp, 35mm/s first layer printing speed, 40mm/s travel speed and 0.1mm layer height.

As you can see, i get a smooth continuity but in some points the model seems to spit some plastic. Like when the extruder changes direction, it gathers a lot of melted material in one place and it falls from the sides.

It looks like plastic bubbles on some corners.

On another model (toothbrush holder), the same thing happens in a smooth surface.

In addition to that, in this model, the surface finish seems to deteriorate a lot at the narrow points where the nozzle does very quick moves.

Printing parameters are same to both of them.

I tried raising temp to 220 and speed to 80 when printing and it became worse i think (i did not let it continue with that parameters).

Could anyone please give me some general advice about printing parameters?

In addition to that, if you could advice me specifically for these examples, i would be grateful.

Thank you in advance and Merry Christmas to all of you!

Andreas S. Gkertsos

 

[gr5 2,167]

Overhangs are difficult - the areas with the worst quality are on the underside of areas that have no support. I don't think you can do much about these except possibly slice thinner layers but layers thinner than .1 sometimes looks worse than .1 so I'm not sure if this will help. If you want "perfect" surfaces, then better to design zero overhangs if possible or make the overhang surfaces hidden (like the toothbrush holder).

The basket looks perfect to me. If there is a problem you will have to highlight it.

The other small bumps and holes - I'm not sure what those are. Maybe someone else knows. Probably a slicing issue. Possibly you can make those better at slower speeds e.g. 25mm/sec. Maybe not.

What was your shell thickness? Perhaps a thicker shell will help. .4mm is not thick enough if you want a nice surface because if only .4mm shell you will sometimes see support structure coming through the side. Always set this to a multiple of .4mm (e.g. .8mm 1.2mm 1.6mm).

 

[illuminarti 18]

Be sure you're using the very latest Cura - version 13.12 was released just a couple of days ago, and there are a bunch of changes being made at the moment regarding how retraction and non-printing moves work, so that might help fix your issues.

Travel speed should be set to 200mm/s or higher. That will help break the threads of plastic when moving between parts of the print, and minimize oozing of the head during the moves between parts of the print. Small amounts of oozed plastic can then catch on the finished surface when the head moves from one part of the print to the other. In the advanced settings, i recommend setting the minimum travel to a small amount, like 1.5mm, turning off 'enable combing' and setting the minimal extrusion amount to 0. That will ensure that you get retraction on all moves except the very shortest ones.

 

You should also consider increasing the acceleration settings for your z-axis, as discussed http://www.extrudable.me/2013/04/02/the-myth-of-z-speed/, to minimise the time taken for changing layers.

13.12 also includes a new firmware that should get retraction working better to avoid the blobbing on surfaces. Once you have that running, set your retraction to 4.5mm at 30mm/s (you may need to increase your maxZ speed setting to allow that).

 

[gr5 2,167]

Do you have a UM Original or UM 2?

 

[illuminarti 18]

Subject says v1 - so I assumed that's what we're talking about :-)

 

[bauermaker 0]

i have to second what illuminarti says, switching to the newest cura solved a bunch of problems for me, some ofthem (the z axis blob) looked pretty similar to your problems.

good luck

 

[andreasgkertsos 0]

Hello friends,

First of all I must say that we are talking about Ultimaker original and I am using the latest cura software since the first print (with the marlin update).

The biggest problem I can point is that bubbles at the point where the z axis makes it's step. How can I adjust the z axis speed?

I will change the parameters as you said regarding the travel speeds but what do you think of the nozzle temp? I noticed a better result at ~200oC than at higher temps.

Thank you very much for your responses.

[gr5 2,167]

Printing slower and cooler tends to get better results. 200C is quite cold but is usually fine if you print at 30mm/sec or slower. The colder the temp, the thicker the PLA is (more like toothpaste than honey). So at colder temps you have to print slower because the pressure in the nozzle can be quite high. And high pressure means the quality won't be as good. You will get underextrusion. But I see ZERO underextrusion in your prints. They don't have that issue.

 

How can I adjust the z axis speed?

 

It's more of a Z axis acceleration issue. I doubled my Z acceleration a while back and I love the results. If you have the ulticontroller, you can change the Z acceleration in there - then make sure you save values and power cycle the machine before testing it out.

If you don't have an ulticontroller, let us know and we can help but the first step would be to install this software which reads the current acceleration when it connects and there are gcodes to change it:

http://koti.kapsi.fi/~kliment/printrun/

 

[andreasgkertsos 0]

I have the ulticontroller. I'll try increasing the z axis speed in my next print.

One more thing, when I start any print the bottom layer most of the times does not stick in the platform and it messes up with the nozzle so I need to restart the program again and again. Is that a temp issue or anything else? I must say though that I do not use any platform adhesion method from cura. Do you think I should do?

[andreasgkertsos 0]

Hello Friends,

I made a new print using the parameters that you suggested me and i can say that things were better this time. The issue i had this time is with the support. It seemed to stick a lot with the model and left some residue in the surfaces after removing them. Well in this particular model, there were a looooot of support so its not the ideal model but ok. I think that I can work that out. I made some changes to the support settings. I made it thinner and i increased the distance from the model. I don't know if that was good.

Anyway i am uploading the model now (Penholder). I also printed a full scale version of the desk notepaper holder.

 

[gr5 2,167]

This is a nice design. It's not clear that you need any support. The UM can do what we call "bridging" as long as the lines are straight. The shorter the bridge, the easier but 4 inch long bridges are not a problem. I recommend trying this print with zero support.

 

[gr5 2,167]

More on bridging here - post #17 (currently last post):

http://umforum.ultimaker.com/index.php?/topic/1872-some-calibration-photographs/?p=25304

 

[gr5 2,167]

I have the ulticontroller. I'll try increasing the z axis speed in my next print.

 

No. Don't touch speed. It never gets up to the requested speed. The move distance is only .1mm or .2mm. Instead increase the z ACCELERATION. Not the speed.

 

[andreasgkertsos 0]

We'll I may need some help here as in my ulticontroller it has 2 categories. "Acceleration" and "Azaxis". Which I think is the acceleration of the z axis. Which one should I increase?

I have to congratulate you for helping a newbie like me guys. I never thought that anyone would pay attention to my post at all. It is very nice to have a living community here. I feel proud for choosing Ultimaker for my 3D printer and I also feel proud that I supported the European market as they are Dutch.

I wish you a happy new year friends and may this year be better for Greece and for every blooding country in the world.

[illuminarti 18]

You want the Z axis one. I think it defaults to 100?

Basically, the 'Acceleration' setting is the overall acceleration that is used. The X,Y, Z and E ones are the per axis maximums. So, the main acceleration value is used, except if it is larger than the smallest max acceleration for any axis used in the move. Then that maximum is used instead.

Typically the Z-axis moves by itself, so its max value is the the one that controls the speed of those moves.

 

[illuminarti 18]

I'm glad that we have been able to help you get up to speed and get good results from your printer. There's a bunch of folks here on the forums who put a lot of time and effort in to helping one another. Between us, and learning from one another's past experiences, we can usually figure stuff out :-)

 

[andreasgkertsos 0]

Hello again my friends,

I printed a new part with the parameters you gave me and i can say that it is getting better and better every day. The only problem i still have is that line at where the z axis makes its step. I increased the acceleration of the Zaxis from 100 to 500 and still that line persists. I may need to tweek the temperature a little bit more because i am still low (215oC). Besides that, after finishing the print, there were a lot of bridges between the 2 "males". As the nozzle moved from one side to another, it was still pouring a bit of plastic. Its was removed without much effort though.

Below i am posting some pictures of the new part (its a connector that i've made for aluminum casting for a local company).

It needed a ton of support because as you will see the whole part is in the air and to be honest i did not believe that it could be printed correctly but somehow it did.

Printing parameters:

Nozzle temperature: 215oC

Printing speed: 25mm/s

Shell thickness: 0.8mm

Infill: 50%

Infill printing speed: 45mm/s

Travel Speed: 180mm/s

Retraction: 70mm/s

Flow: 100%

Support: Touching buildplate.

Printed Using Cura 13.12

 

[andreasgkertsos 0]

Layer Thickness: 0.15mm