Review: Prusament PC Blend  

RE: Review: Prusament PC Blend

Posted by: @cynan

So I guess print spare PETG parts first? Urgh... or perhaps just source someone else to print them?

Printing a complete set of spare PETG parts is a good idea, just in case.

Having said that - you can order spare plastic parts from the prusa shop:
https://shop.prusa3d.com/en/70-plastic-parts

RE: Review: Prusament PC Blend

@loadinglevelone

Definitely have a back up for parts that might melt.  

RE: Review: Prusament PC Blend

@cynan

PC Blend is not a great filament for all parts.  It tends to warp some so larger parts are not ideally printed in PC Blend.  

RE: Review: Prusament PC Blend

Thank you both. 

RE: Review: Prusament PC Blend

@cynan

Glad to be of service!  I will be testing it more this weekend and will pst the results.  

RE: Review: Prusament PC Blend

@cwbullet

The new R6 parts might fix that. I print in Polymaker PC max and Nylon (both generic and Fishy Filaments) quite a bit so will let you know. The R5 part was supposed to fix this. I would be interested to hear how this compares to PC Max - the only issue I have with PC is that you need a LOT of glue stick or it pulls the surface away from your PEI sheet.

RE: Review: Prusament PC Blend

I cannot get the PC blend to stick to the bed at all! My MK3S MMU2S has several thousand hours of PLA/PETG so it is fully functional. Trying to get my printer to temp throws an M112 about 80% of the time. (265/112) The bed will not get to 115C at all. I am forced to put a towel over the bed to get it to not throw mintemp errors during preheat. Ambient is 75F (23.9C). I really need to make this work. Any suggestions?

RE: Review: Prusament PC Blend

Posted by: @txbillbr

I cannot get the PC blend to stick to the bed at all! My MK3S MMU2S has several thousand hours of PLA/PETG so it is fully functional. Trying to get my printer to temp throws an M112 about 80% of the time. (265/112) The bed will not get to 115C at all. I am forced to put a towel over the bed to get it to not throw mintemp errors during preheat. Ambient is 75F (23.9C). I really need to make this work. Any suggestions?

Yes, first be sure that the power connectors to the bed heater are VERY clean and tight, both at the bed heater end and at the Enisy end and at the power supply end as well.  I would just go through and snug up all of the power connectors from the power supply through the Einsy and to the heat bed.  A little resistance in any of these can cause failure to heat to the higher temperatures.

RE: Review: Prusament PC Blend

@jsw

Very true and it can also create fire risk.  

RE: Review: Prusament PC Blend

Connections checked and found no issues there. I have a spare controller. I think I will swap that and see if I have a faulty MOSFET for the bed. It is more likely copper fatigue do to the design of the sleeve/mount of the bed cable. That particular design has several failure vectors. With several thousand hours of printing, it is highly suspect. I have already replaced the thermistor cable twice.

RE: Review: Prusament PC Blend

Tin can cap size issue

Design: cap for a tin can. Outer diameter 78.0 mm. inner diameter 75.0 mm. Height 9.0 mm. Designed with Fusion 360. Material: Prusament PC Blend (black). Printer: Prusa MK3S. Settings: 0.30mm Draft. Kores glue stick. No enclosure.

Issue: actual inner diameter of the print is 73.7 mm instead of 75.0 mm.

Does anyone recognize this issue? Does it have to do with the settings? 

RE: Review: Prusament PC Blend

@txbillbr

I use a towel as well, just to heat the bed faster, I'm not getting a min temp.

However you might check that the bed thermistor is seated against the bed properly, I've had them get tugged and pulled a bit leaving a small void in the Kapton that holds it to the bed.

just a thought.

RE: Review: Prusament PC Blend

Design: cap for a tin can. Outer diameter 78.0 mm. inner diameter 75.0 mm. Height 9.0 mm. Designed with Fusion 360. Material: Prusament PC Blend (black). Printer: Prusa MK3S. Settings: 0.30mm Draft. Kores glue stick. No enclosure.

Issue: actual inner diameter of the print is 73.7 mm instead of 75.0 mm.

Does anyone recognize this issue? Does it have to do with the settings? 

 tincancap.JPG

That would make the error 1.3mm, or about 1.7 percent, which, in my experience, is a bit larger than I would normally expect, but still within the ballpark of what the machines can be expected to do.  There are many factors involved, such as the size of the bead and the degree of "squish" and such.  Also, I've found a difference between PS and Cura when making close-fitting parts.

When I do close-fitting items and I don't already have a degree of "feel" for how they will fit together when printed, I'll always do test prints and then tweak the dimensions slightly if needed.  For example, for smaller registration pegs using the Prusa printer, PS, and ABS or PLA, I'll usually make the peg .1mm smaller in diameter than the corresponding socket.  For windows on model railroad buildings, both rectangular and circular, I try to go for a "snap fit" which will assemble without too much force and stay without adhesives.  Most are a three-part fit with the side of the building, the window frame, and the window pane.  Usually a .1 to .2mm difference gives the fit that I want.  If the fit does not work, I'll carefully measure both parts with a digital caliper and make tweaks, usually in the .05mm to .1mm range.

I try to do all close-fitting items in the XY plane, and your can lid would be an example of this.  LOL, all bets are off for close-fit items printed in either Z plane.  😉

RE: Review: Prusament PC Blend

It might warp a little during print. 

RE: Review: Prusament PC Blend

@jsw & @ cwbullet, thank you for your responses.

The 4th print fits perfectly around the tin can. The inner diameter of the cap is 75.40 mm and the outer diameter of the can is 75.00 mm.

I got the impression the PC Blend prints tend to shrink a little after printing. Cooling down from 275 C slowly seems to have a positive effect cq. reduces the shrinking. Does this sound plausible to you? 

The end result is really very nice.

RE: Review: Prusament PC Blend

@swiss_cheese

I gave up on the issue. I built a Voron 2.4 to print higher temp filaments and went back to PLA/PETG on my Prusa. The MK3S is a great little printer, but like all printers has some things that need some improvement.

RE: Review: Prusament PC Blend

@txbillbr

MK3S works fine at higher temps with the right parts.  

RE: Review: Prusament PC Blend

@jsw & @ cwbullet, thank you for your responses.

The 4th print fits perfectly around the tin can. The inner diameter of the cap is 75.40 mm and the outer diameter of the can is 75.00 mm.

I got the impression the PC Blend prints tend to shrink a little after printing. Cooling down from 275 C slowly seems to have a positive effect cq. reduces the shrinking. Does this sound plausible to you? 

I haven't used enough PC Blend to get a handle on shrinkage.

I do know that ABS does shrink a bit, but at one of the classes I took we were told that the stock slicer for the Uprint machines (Catalyst? don't really remember) compensated for this and just do your drafts for ABS prints with final dimensions.

When I started with my own printer (MK3S) and ABS, I started using final dimensions and have not yet had a need to adjust.  In several of my model building facades the main body is PLA, the window frames are black ABS, and the window panes are so-called transparent PETg, and all are drafted using final dimensions except for the .1mm to .2mm or so clearance I mentioned above and everything fits.

I actually have no clue if PS does any shrinkage compensation or not.  Anyone know for sure if it does or does not?

RE: Review: Prusament PC Blend

@jsw

I have had ABS prints shrink by 2-8% so I slow increase by 1% with test prints till the part fits.  

RE: Review: Prusament PC Blend

@pamelawardtx

Your post seems random and disconnected from the subject matter, as it stands.

Wrong window or forum? maybe?

it's unclear what your trying to say.