ColorFabb CPE_HT Printing With Burn Marks

[Lord_LolzWorth 0]

Hello all,

 

We are trying to print clear CPE+ but so far have not had much luck. The main problem we are having is the scorching marks seen in the images and also large clumping of material on the prints. It seems it builds up on the print nossle before dislodging itself and getting stuck inside the print. 

 

Does anyone know of a way to improve the print result for CPE+?

 

Settings / Hardware / Filiament used are below:

 

Ultimaker 3

 

Filament: ColorFabb_HT 2.85mm

 

 

CURA Version: 3.2.0

AA 0.4 head

0.06 Layer Height

100% infill

Print Temperature: 262 C

Build Plate Temperature: 110 C

Flow: 110%

Retraction Enabled

Print Speed: 20mm/s

 

 

Thank you all in advance.

 

 

[DidierKlein 648]

Hi and welcome,

 

I would probably go for a higher layer height, i think .1 or .15 is still enough for this kind of print.

 

Also is the flow to 110% needed?

[Lord_LolzWorth 0]

Hi DidierKlien,

 

I followed the ColorFabb recommended settings for an Ultimaker 2 as they had none for the Ultimaker 3, you can read here: https://learn.colorfabb.com/lets-make-something-clear/

 

They also used a print head 0.8 instead of 0.4. I will adjust the layer height to 0.15 instead and use 100% flow and report back my findings. 

 

Thank you for your replay. 

[DidierKlein 648]

you want to make it transparent or just print ?

 

This link is to make the print the most transparent possible (it's not an easy process)

[kmanstudios 670]

I took a look at the link. They also have scorch marks in their prints. I believe that comes from moisture in the filament carbonizing and then sticking to the nozzle.

[Lord_LolzWorth 0]

15 hours ago, DidierKlein said:

you want to make it transparent or just print ?

 

This link is to make the print the most transparent possible (it's not an easy process)

The end goal is to make it as transparent as possible while maintaining a good finish. Just need to find the balance.

15 hours ago, kmanstudios said:

I took a look at the link. They also have scorch marks in their prints. I believe that comes from moisture in the filament carbonizing and then sticking to the nozzle.

I actually only just noticed this myself thank you for pointing this out. Perhaps this is a normal characteristic that just has to be lived with? We live in a very humid climate and our only dehumidifying ability is by air conditioning.

 

I have attached photos of the 0.15 print. The scorch marks are still present but vastly reduced, however the transparency is not where we want it. I am going to try printing at 0.1 today and post those results as well. Settings used for this print were:

 

Settings / Hardware / Filiament used are below:

 

Ultimaker 3

 

Filament: ColorFabb_HT 2.85mm

 

 

CURA Version: 3.2.0

AA 0.4 head

0.15 Layer Height

100% infill

Print Temperature: 270 C

Build Plate Temperature: 107 C

Flow: 100%

Retraction Enabled

Print Speed: 45mm/s

 

Essentially Cura defaults for that profile speed.

[geert_2 193]

You might want to look at your models under a microscope, if you have one available. Or make pictures with a camera with good macro. It might help finding the cause of the opaqueness. If you see tiny bubbles or milk *inside* of the extruded sausages, or sort of craters that popped open on the surface, then it is probably moisture, and then you need to thoroughly dry your filament. If there are no bubbles or craters, and the sausages are fully transparant, but the whiteness is caused by the air trapped between sausages, then you need to improve the filling while printing, by improving the flow.

 

If I remember well, user |Robert| also tried printing a transparant block, with good results. Maybe you can find his post back for his settings?

 

Personally, I would try to print test blocks of 10mm x 10mm x 10mm, with various settings: starting at a low speed of 20mm/s (to get good flow into all corners and voids) and at a lower temp (to avoid burning the material). For PLA and PETG this usually works, but I have never printed with this material, so I don't know here.

 

In PETG I have also seen material accumulating on the outside of the nozzle, and then sagging onto the print. This seems to be because it is more rubbery and sticky than PLA, which is more liquid like yoghurt. Printing cooler helped here too: it did not totally prevent the accumulation, but at least it didn't get brown.

 

[Lord_LolzWorth 0]

On 3/8/2018 at 9:06 PM, geert_2 said:

You might want to look at your models under a microscope, if you have one available. Or make pictures with a camera with good macro. It might help finding the cause of the opaqueness. If you see tiny bubbles or milk *inside* of the extruded sausages, or sort of craters that popped open on the surface, then it is probably moisture, and then you need to thoroughly dry your filament. If there are no bubbles or craters, and the sausages are fully transparant, but the whiteness is caused by the air trapped between sausages, then you need to improve the filling while printing, by improving the flow.

 

If I remember well, user |Robert| also tried printing a transparant block, with good results. Maybe you can find his post back for his settings?

 

Personally, I would try to print test blocks of 10mm x 10mm x 10mm, with various settings: starting at a low speed of 20mm/s (to get good flow into all corners and voids) and at a lower temp (to avoid burning the material). For PLA and PETG this usually works, but I have never printed with this material, so I don't know here.

 

In PETG I have also seen material accumulating on the outside of the nozzle, and then sagging onto the print. This seems to be because it is more rubbery and sticky than PLA, which is more liquid like yoghurt. Printing cooler helped here too: it did not totally prevent the accumulation, but at least it didn't get brown.

 

Unfortunately don't have access to a microscope or a macro lens of any sort. We printed another print at 0.1 layer height but I have not got any photos to post. Results were actually worse on this print in terms of carbon. I think that given the amount of humidity present in our weather it would be highly probably that water is present in the filament. I am going to investigate ways of drying the filament out and then doing some test prints to see if the results clear up.

 

Thank you all for your help so far, fantastic community.