Rough surface - bad quality

[shurik 87]

Hi,

While waiting for a new teflon thing and the new bowden, there are still prints to do.

Please see the surface quality:

0.1mm height, 30mm/sec, 220-230C (no visible difference).

Using Faberdashery Architect's Stone.

If you zoom the photo, the roughness of the surface can be seen, even with some little underextrusions here and there, although no clicks occur and in general, the result is acceptable yet.

However, where is my beloved Ultimaker quality? I want it back...

 

[tommyph1208 55]

You are printing PLA at 230C!?

I would say that is waay too hot, and might be (at least one of) the reason(s) your surface looks the way it does...

I would try somewhere around 180-190C, that might help you get rid of some of that massive stringing between the towers as well...

 

 

[pm_dude 27]

With a clean nozzle and a teflon piece not deformed you should be able to print at around 200-210C for the same speed. That will improve surface quality and reduce stringing a lot.

What happen if you print at 200C?

You might want to give a good clean to the nozzle using a few atomic pull or using a torch to burn the pla inside.

[tlrt2701 0]

I print PLA with 235 with no problems. I think this is underextrusion and to low Travelspeed. Can you clean your Nozzle with atomic method?

And how much hours do you print with your UM2?

 

[shurik 87]

Thanks for the replies guys.

The nozzle is supposed to be clean, I gave it a few atomic pulls not too long ago.

If I will lower the temperature, it will jump and underextrude heavily.

My UM2 is almost one year old (yaw!), oiled the axes several times and did all kinds of small maintenance things over that time. However, as I put it in another thread, the Bowden tube looks worn out and there is strong suspicion about the teflon although the visual inspection of the later found nothing outstanding, just wear of the time.

 

[yellowshark 153]

If you are printing 100 micron layers at 30mm/s then going to 230 is unnecessarily way too hot and will not be doing you any favours. If you have to do that then you are masking a problem which in the longer term you will benefit from finding and fixing. I have not used the Stone filament but with those settings you should be able to easily print most Faberdashery filaments at 200.

 

[mnis 11]

Hey, my Ultimaker December 2014, had also anniversary. And the first ColdEnd was needed after nine months. A new Bowden and a temperature sensor also had to be bought, but that was more assigned to my fault (.... something like initial ignorance). But that is past and most of the time i get good to very good objects with various PLA varieties.

Anyway, I'm also of the opinion that 195 - 205 degrees for most of PLA varieties are almost ideal, and only then, can arise objects with the best possible quality.

Below 195 degrees there can be problems for objects with fine static elements, too great a tendency to fracture is the result. Artworks succeed better below 200 degrees and less stringing is given.

Above 200 degrees can be very stable objects are created, but with rising temperature significantly increasing stringing is really annoying, and it requires a lot of post-processing. It is highly recommended if only one object is printed at the time.

Slow printing at very high temperatures, arise very quickly combustion residues in the Hotend, and the result is a fully or partially clogged Hotend.

Tip:

Protect your new soon got UM2 ColdEnd against rapid wear of!

My guess is hundreds Retractions cause fewer problems than a single one careless material change.

Cold PLA is very brittle, be careful when changing material: Particularly sharp filament breakage points and strongly curved ends are a major problem, they can damage the transition zone of the ColdEnd very quickly. In the very hot transition zone to the Hotend, the PTFE ColdEnd is much softer than in its upper and much colder Region.

Markus

 

[shurik 87]

Thanks for the help!

After carefully reducing the printing temperature to 205 and even 200C, the overall quality improved as adviced here.

However, these horrible underextrusions... They didn't get worse, but when printing the raft, the printer clicks violently many times. Then, it behaves more or less normally when it prints the parts themselves. Well, most of the times. Ohhh. And the UM were unable to ship me the teflon coupler, so I'm stuck....

 

[pm_dude 27]

If you know the teflon piece is deformed you can drill it.

 

[mnis 11]

...AND...

Hey, do not despair, there is nothing lost.

- You could try via: www.aliexpress.com ;to obtain a UM2-PTFE-ColdEnd (replica). No opinion on the overall quality, but the price is OK. And eventually you get the part faster than from Ultimaker. But in any case, there is no risk the machine with such a part to damage, i think.

- Brim for PLA: You need it really only for very large objects by direct-printing on glass, otherwise suffice Skirt.

- As a rule: The first layer, is very hard for the machine to create. Maybe you adjust the print bed again with a generally larger nozzle distance to the glass surface. That should help to get a cleaner result in the first layer. And the stepper motor should then be able to move more consistent material.

- Always remember: "A thorough interior cleaning of Hotend", "Additional material guides to install", "Check the Bowden seated correctly", "A thorough internal cleaning of the original material feeder", "Try a alternative feeder", "Try another filament varieties"," Temperature and speed must always harmonize with each other ", " Not every material can generally be used at high Speeds, this usually has to be previously figured out".

 

Markus