Da Clumsy Noob goes back to printing with PC

[kmanstudios 1,120]

Well, if it ain't been fun LOL

OK....I see some posts every now and then about materials not behaving. Well, what behaves in one scenario will not always hold true. There are many factors that can play into things:

 

• Environmental Changes
  
• Batch differences
  
• How one printer handles varying brands of the 'same' material
  
• Possible material 'recipe' changes over time
  

 

I have been working on an articulating model for a client that I did some animation for. I prototyped in PLA because I gots boat loads of the stuff.

I switched over to PC to make my final product for strength purposes. I am using Ultimaker Black PC.

Now, I did not expect the PLA and PC to have the same tolerances on the side of printing, so this is really about the differences between the PC I printed with before and the PC I have now. I purchased this PC material a few months ago and am just now getting back to using PC.

I am also using the print cluster software, even though I am on one printer. Why? Because I can stack jobs of a like kind and just have to be there for when the print is finished to change plates, clean, apply Papa K's Magical Slurry Sauce for stickum and then override the controls to accept the chosen material. I am having to do this even though I have Ultimaker PC. I am thinking I got a batch of PC that did not have the NFC chip on it. It has been dry in NYC and I left my PLA loaded in the polybox and just hung the PC on the spool as designed. Still did not see the PC and had to choose generic.

No pops or crackles so the filament is dry. PVA is working well with it too. But, I did have to make a few adjustments on the presets in Cura for the PC settings.

I found that the default temp of 107°C was just too much. It really cooked the Slurry Sauce onto the buildplate as well as virtually cemented the PC to the glass....for the most part....

And I was getting some stringing. Please note that I am using a front cover to keep the heat in.

So, I had read in another thread about how the buildplate heat can keep the material too soft and allow for warping. I was getting a tiny bit of warping on a few odd places.

So, I took the buildplate temp down to 100°C for the first layer and then 95°C from that point on. 90°C and then 80°C was too cold and it would not stick to the plate. It now releases the parts much easier from the buildplate as well as allows the Slurry Sauce to not get cooked so hard. I mean I was having to soak things for hours just to get them to loosen a bit and sometimes, run very warm water over the buildplate for about an hour just to get parts off and finally get off the thin film of Slurry Sauce. I did manage to also put some really bad dings in two of my buildplates (Pitting the glass with large gouges) and this has not happened since the cutback on buildplate temp.

Also, I finally wound up with a material setting of 257°C for my Default printing temp and allowed Cura to figure all the rest of the temp settings from there. I had to bounce around a bit to get the right temp.

250° was too cold and did not want to lay down right, even when slowing the printing way down.

260° was still a bit stringy. That 3° made all the difference in the world.

Now, I am having no warping and no hassles getting my pieces off the buildplate. I am using a PVA brim, the Slurry Sauce is PVA based and using PVA supports. I am getting clean prints (With this type of design anyway) and other than printing at 0.1mm/100µ and the time it takes, all is now going well.

I also had to create a counter weight in one of the pieces because when the crane boom extends, it was throwing the model out of balance. That was fun as I just made a hollow in the model, printed to a point above the nuts I was using for weights, squished some glue into the hole and dropped the nuts in and allowed it to finish the print above it.

Edited November 26, 2017 by Guest

[cjryker06 0]

You were able to get PVA supports to work well with PC? I was wondering if more were possible than the materials chart implies. I just got some Polymaker Poly-Max to try out. I kind of question the CPE vs. CPE+ as well considering PVA support from E3D states it works with Colorfabb nGen which is also a PET based co-polymer like CPE/CPE+

[kmanstudios 1,120]

You were able to get PVA supports to work well with PC? I was wondering if more were possible than the materials chart implies. I just got some Polymaker Poly-Max to try out. I kind of question the CPE vs. CPE+ as well considering PVA support from E3D states it works with Colorfabb nGen which is also a PET based co-polymer like CPE/CPE+

Yes, I got the PVA to work with the PC. But keep in mind that it may just be the type of geometry in use. And, a couple of times, it would just peel up if there was a rush of cold into the area.

For instance, I had a print on today that was doing fine when I left. It has been getting colder here in Brooklyn but dry as well. So, I have been cracking the door to let in fresh air. I live in a basement apartment (Which I do love btw) so, cracking windows is not an option.

When I returned home from an appointment, it had warmed in the apartment. As soon as I came in opened the door and cracked it slightly, the sudden heat differential made a long piece warp enough that I had to abort the print. I know this to be as I had seen how well it was printing before the cooler air reached the print.

I also had to go to a PC Brim on One object because it just would not stay on the plate in one place. I think I found the issue (I made the part too thin and the PVA on top of it would pull as it cooled...so, user error) but am still printing with PC Brim.

I am hoping to post further about this with pics once the project is done since I did a few nifty things like the PVA supports, but also because I did a print, pause, fill with weights, and let print finish to enclose weights.

But, I do know it does not always work with the PVA.

Here are two pics of dolphins I printed in black PC that used PVA as a support:

[cjryker06 0]

Thanks for the info. I have the tamper proof door and custom cut PEI sheet coming for my printer so those will help mitigate many adhesion/temp differential issues. I was hopeful that I could use PVA with PC. After being told PVA wouldn't work with PC or PET based materials due to printing temp differences. I was a bit disappointed since I got Polymaker Poly Plus cheap for Black Friday and would love to use nGen as a general purpose material. Supports would be great.

I do agree that geometry will have a lot to do with it. Your prints have a lot of surface contact. Flats will also likely be fine. It's going to be the more intricate things PC isn't exactly supposed to be used for that will be the true test.

[kmanstudios 1,120]

Thanks for the info. I have the tamper proof door and custom cut PEI sheet coming for my printer so those will help mitigate many adhesion/temp differential issues. I was hopeful that I could use PVA with PC. After being told PVA wouldn't work with PC or PET based materials due to printing temp differences. I was a bit disappointed since I got Polymaker Poly Plus cheap for Black Friday and would love to use nGen as a general purpose material. Supports would be great.

I do agree that geometry will have a lot to do with it. Your prints have a lot of surface contact. Flats will also likely be fine. It's going to be the more intricate things PC isn't exactly supposed to be used for that will be the true test.

 

Not everything I have is flat or large geometry. I do have some spindly things I have to futz with to get them to print correctly. This usually has more to do with putting multiples on the buildplate and turning them in different orientations to see what works. I also do try to minimize contact.

Edited November 30, 2017 by Guest