Black ePC - disappointing first print

[Phil]

I have used the MakerGeeks black PC. It is very hit-or-miss. Lots of warpage, tough to keep on the bed.

[Gwhite]

I want to use this to print a couple new filament drives. I found an old ePC factory file, but it predates the black version, and is presumably for the clear stuff. I know Zemlin had issues with the black early on, but I'm hoping eSun has improved the stuff and/or folks have figured out the magic settings to get it to behave well.

From examining old threads (including this one), some people claim you need to run the extruder around 300C to get good strength & layer adhesion. That more than 10% above eSun's recommended temperature, so I'm a bit nervous to go that high unless it's more than one old anecdote..

Besides aftermarket build surfaces, someone reported good results with painters tape. I haven't seen any reports on how hairspray or glue stick work on either glass or polyimide. One post said hairspray works well on mic6, but I'd like to try to get the factory build plate working.

So, any updates on dealing with black ePC?

Thanks!

[jferguson]

Karl, I've been printing eSun PETG clear at 247C for thin shells for R/C aircraft wings. they seem pretty strong to me, but i will have to mess with rafts to deal with what appears to be some shrinkage distortion just above the table - first 3/8 inch or so. No fan, bed at 87C.

What temperature do you like for this?

john

[zemlin]

Karl, I've been printing eSun PETG clear at 247C for thin shells for R/C aircraft wings. they seem pretty strong to me, but i will have to mess with rafts to deal with what appears to be some shrinkage distortion just above the table - first 3/8 inch or so. No fan, bed at 87C.

What temperature do you like for this?

john

I print eSun clear PETG on PEI (Ultem) with good results. Kapton can work fine too, but the PEI gives a bit better adhesion. I have seen the low-level distortion. I decided it's from the bed temp being too high. I run at 80C. At 85C I'll see the shrinkage on the low layers. My nozzle temp for clear eSun is 240C. For single-wall prints I limit the speed to 1200mm/min. That's with a .6 nozzle and a .25mm layer. I am not running this on a Makergear printer, but I have in the past. Corners get a bit messy at higher speeds.

[jferguson]

thanks much Karl, I imagined 247 was a bit too hot.

I've had very good luck with elmer's extra strength stick glue on kapton. I have a piece of fiberboard which I use for removal of prints where there is a fairly solid face sitting on the kapton. I put the glass on a bench, line up the fiberboard with the bottom of the print and whack it with a mallet. print usually shears right off and unless there isn't much meat close to the bottom, there's no damage.

I bought onwe of the aluminum platforms with rhe pei on it with the thought that I'd switch over if i had trouble with the kapton, but so far printing PLA and PETG AND with the sorts of things I print, no problem.

BTW, I caved and bought a subsription to CREO with the additional CNC package. It runs a whole lot faster the Rel 12 on the old SPARC10. Their documentation is not great and I waste some time trying to figure out how to do stuff I could do off the top of my head in 12. But in the end, I think it's worth the cost.

best regards,

john
.

[airscapes]

I know this thread is ePC but you guys are talking about PETG ..been printing PETG on the Polyimide tape (i assume it is Kapton) and had NO issue with it sticking.. it is getting it off if the part is large.. Smaller parts can be hit with refrigerant (canned air upsidedown) and they will loosen but I have had larger stuff pull the tape off the glass.. Same for the EPA, that stuff is the worst, have to use glue stick so it can be removed without removing the tape by running the part and glass under water to remove the glue. still a real pain and time consuming to get the freaking things off.

[Gwhite]

This WAS a thread about black ePC, but it's gotten hijacked. If you want a suggestion about dealing with PETG, I just posted a reply in a thread that is actually about PETG.

viewtopic.php?f=3&t=6739&p=36884#p36884

[jferguson]

sorry guys, clearly i have a disicipline problem/

[zemlin]

Well, back on the topic of black ePC, I finally had reason to spool it back up and see what I can get from it again.
Just to clarify, my M2 has been removed from service and replaced by Raise printers, but I see that as a fairly minor detail in this subject.

eSun had suggested I run the black at a lower temperature, and some subsequent testing I did with PETG indicated that might be a reasonable request. eSun black PETG was more brittle at higher temperatures.

I wanted to test PC with a .2mm nozzle for some small, detailed parts. I had just finished drying my black and clear ePC spools in a vacuum chamber. I spooled up the black and ran a build with 6 vase-mode calibration cubes at temperatures ranging from 250C to 300C. Below 290C the layer bond strength fell off significantly, so running at lower temps was not going to result in stronger parts. I ended up printing the black at 295C and the printed parts were still fairly brittle. I ran the same build in clear and the clear parts are far stronger. Trying the clear parts again at 305 just to see how they do.

I have a spool of white I'll be trying later today for comparison, but it seems the black just isn't going to compare to the clear for part strength.

For a .2mm nozzle build, the parts look excellent, both in the clear and black. I'm using a .1mm layer thickness and support is separating nice and clean.

[jferguson]

Karl,
is the new printer enclosed? I ask because one would expect the black ePC to emit heat faster - ie, cool down sooner, which might affect adjacent layer bonding.

If extruding at a higher temperature causes other problems, it seems possible that there is no (NO) satisfactory way to print with this particular black mix except maybe in a controlled environment where you can both print at a lower temperature than the range which produces thw brittleness while reducing the rate of heat loss from what's already been printed.