CPE Weird Print result

[stan_bulgaria 4]

Hello Torgeir,

 

thank you for your support. 

 

I'm now trying how it will print with transparent PETG from a local Bulgarian filament producer - Rast 3D. So far the settings show to be with lower temperatures for the same result:

Nozzle = 205 C

Bed = 70 C

Fan = 205 rpm

Speed = 25 mm/s

 

Regards

Stan

 

[Torgeir 242]

Hi Stan,

 

Good progress.

I made quite a few test with your "test" model and found that, by just adjusting the "Z Seam Alignment" to:

"User Specified" and "Z Position" to "Back" you may have fare less blob on the surfaces of the model.

There is just a little you have to remove around the edges, but look much better IMO., in the preview mode using the "gcode" file that is ready to be printed.

This is the only adjustment I made to your file.

 

Good Luck

Torgeir

[stan_bulgaria 4]

Hello Torgeir,

 

good idea. It worths a trial and I'll check it when printing shells again.

 

For the moment I have overcome the problem as I changed the model and inserted a support for the shell as Geert advised, with a very small gap of only 0,2 mm. In that way the surface covered by the support is good and has some blobs only around the edges. It is easy to remove the blobs afterwards even with finger. 

 

I've already broken two of the finished models and I've noticed something, which perhaps cannot be skipped. The detail body consists of three cylinders with different sizes. The connection between the cylinders is a weak point. That's because the cutting plane is parallel to the layers surface. I'm not sure if rising the temperature of the nozzle only for that 2-3 layers would do any difference. On one hand the higher temperature should stick the layers probably stronger but the material will be more rigid and not flexible at that plane. So at sudden start of rotation again can happen a debonding/cutting. 

 

I believe that is a major question and has to do with the producers of the filaments.

 

Regards

Stan

[friedl_basson 5]

Hi @stan_bulgaria - 

 

It seems you have sone a lot of research and testing with CPE.  I am sorry I cannot give any advise, but was hoping you could impart some of your knowledge onto me.

 

Like yourself, I have started printing with PLA until such time that my model was finalised and then switched to CPE due to harsh environment this enclosure will be in. This is where my troubles started from the get go... even with  a very simple component, I just cannot get all four corners of the part to stick to the bed.

 

I have tried just about everything I could find in the forum, but no luck.  In a desperate attempt I have now switched the orientation of the part as the model was constantly warping on the far right corner. Even if this work, it wont solve my problem as other parts of this model are much larger and more complex.

 

Funny enough, I have had the worst results using BRIM.  I could not even finish printing the brim without it detaching form the build plate.  My current settings are:

• Filament: Ultimaker CPE
• Printer: UM2+
• Nozzle: 0.4mm
• Layer height: 0.15mm
• Temp: 250C
• Bed Temp: 70C
• Flow: 100%
• Fans: 50%
• Adhesion: Using Magigoo and heated bed
• Enclosed front (have also tried open)

For my latest attempt (still printing) I have cleaned the nozzle, cleaned the bed with Isopropyl and then added fresh coat of Magigoo.  Also levelled the bed (AGAIN). It seems to warp about 1 hour into the print.

 

Kind Regards,

Friedl.

 

[stan_bulgaria 4]

On 2/21/2021 at 5:03 PM, friedl_basson said:

Hi @stan_bulgaria - 

 

It seems you have sone a lot of research and testing with CPE.  I am sorry I cannot give any advise, but was hoping you could impart some of your knowledge onto me.

 

Like yourself, I have started printing with PLA until such time that my model was finalised and then switched to CPE due to harsh environment this enclosure will be in. This is where my troubles started from the get go... even with  a very simple component, I just cannot get all four corners of the part to stick to the bed.

 

I have tried just about everything I could find in the forum, but no luck.  In a desperate attempt I have now switched the orientation of the part as the model was constantly warping on the far right corner. Even if this work, it wont solve my problem as other parts of this model are much larger and more complex.

 

Funny enough, I have had the worst results using BRIM.  I could not even finish printing the brim without it detaching form the build plate.  My current settings are:

• Filament: Ultimaker CPE
• Printer: UM2+
• Nozzle: 0.4mm
• Layer height: 0.15mm
• Temp: 250C
• Bed Temp: 70C
• Flow: 100%
• Fans: 50%
• Adhesion: Using Magigoo and heated bed
• Enclosed front (have also tried open)

For my latest attempt (still printing) I have cleaned the nozzle, cleaned the bed with Isopropyl and then added fresh coat of Magigoo.  Also levelled the bed (AGAIN). It seems to warp about 1 hour into the print.

 

Kind Regards,

Friedl.

 

Hello Friedl,

apologizes for not answering on time - I just saw your question.

 

My experience is very limited.  I'm using two types of CPE (PETG modified) filaments. For harsh conditions I prefer Fillamentum CPE HG100 and for normal use RAST 3D PETG.

In general I found out that for my printer Creality Ender 3 V2, the temperature settings are lower than the respective filament recommended.

1. So in order to find the most appropriate temperature settings I make a test to see at what temperature the filament starts flowing freely out of the nozzle.

2. Then I make a test what is the best temperature for the bed - go with increment of 5 degrees. In some of the filament TDS it is recommended bed temperature of 105 degrees. For me 75 was perfect and above 80 debonding was higher than below 70 - funny.

3. Then when the temperatures were set and the printing started another phenomenon appeared - just like with your detail, mine stared debonding from the bed (may be 2 hours after the print started). I understood I have skiped un important step - bed adhesion. Here in the forum is a very extensive topic about bed adhesion. Mine solution was hair spray on bare glass. Yes, I tried the salty water and the wood glue solution, but so far the hair spray and CPE HG100 or RAST 3D PETG work best together.

4. To make the adhesion even better on the initial layer I don't use fan at all. This has a bad result if your initial layer is a flat surface as you'll get blobs or warps, but normally the next layer will hide that imperfections.

5. For the shell details, like the rectangular pipe you want to print, I use raft to enhanse the adhesion to the bed. You'll use extra time and material but the deformations that may accure will be less.

 

I attached two of my projects so you can see my settings. On Dograma... project I have some issue for which I'll open a new topic.

 

I hope this information can be of help to you.

 

Regards

Stan

Dograma podlozhka.3mf Anemometer4 final.3mf

[friedl_basson 5]

Hi @stan_bulgaria - 

 

No problem.  I am not on the forum often either and for some reason I do not get emails when someone replies to a topis I posted.

 

Thank you for all the information.  I will try again... and again... and again (it seems, haha).

 

If I indeed find a successful set of settings, I will be sure to post them here.  I know one thing, it is for sure not the settings that appears on the label of the CPE product 😄  Just with regards to bed-adhesion, I use Magigoo and not even that could get the part to stick.

 

Many thanks!

Friedl

[stan_bulgaria 4]

Hi Friedl,

 

unfortunately with so many filament and printer producers, plus local weather conditions that can play a role, it is difficult to have universal temperature settings for a type of material. As more complex the polymers are more things affect the printing result. But finding the correct settings once, after that it is fine tuning.

 

Just an idea. Try to set each setting one by one - first try the bed temperature. When you are satisfied with it do the step by stem setting of the nozzle temperature.

 

Regards

Stan