HIPS versus PETG with a Lulzbot TAZ5

Hello Lulzbot users,

Printer : Lulzbot TAZ5
Slicer : Simplify3D

I thought I would post some images and my findings following experimentation with both HIPS and PETG filament. Up to
this experiment I have been using almost exclusively HIPS. I have been printing sculptures and arty objects but also more
practical brackets and the like.

My latest project has been to build the Ciclop 3D scanner. This project required the printing of quite a few components some
of which were quite large with overhangs and other tricky structures.

If anyone is interested I have put together an Instructable describing the project:

When printing with HIPS one or two of the parts have given me problems with shrinkage resulting in corner lift from the bed. I
have tried many different approaches to mitigate this problem as follows :

  • Changing the bed temperature from 110C down to 80C
  • Incorporating localized brim
  • Enclosing the printer as best I could
  • Changing the number of base solid layers
  • Changing the fan speed and presence

After much trial and error I did manage to improve the corner lift problem. I loaded the models into Meshmixer and added in
localized corner 1mm brim but even then the corners lifted even within the brim itself - see the images.

I then decided to have a go printing the object using a new filament PETG. I found PETG to have advantages and disadvantages
but overall the advantages were clear.

HIPS

  • Prints generally very well
  • For larger parts corner lift seems almost impossible to cure
  • Can be vapor smoothed easily
  • Produces a pleasing mat finish
  • Low levels of ooze and stringing
  • Very strong
  • No smell

PETG

  • Prints generally very well
  • Almost zero corner lift or shrink at all
  • Vapor smooth - not tried so far
  • Finish is slightly glossy
  • More ooze and string than HIPS but fixed with profile tweaks
  • Very strong (stronger than HIPS/ABS)
  • No smell

I have been printing the PETG at 240C extruder and 100C bed temperature. I think from now on I will be printing with PETG
simply because the levels of shrinkage and distortion are so low compared with HIPS/ABS.

Any questions or comments please fire away.

Cheers,

Dave


Anyway enough words, here are some photographs to show the results :






Hi dtrewren,

Thanks for the post. I have been experimenting with PETG myself and just ordered some natural PETG to try printing a large part that has failed twice in ABS (massive layer splitting). Besides your 240/100 temp settings, would you share your other settings for printing with PETG? Maybe make a Rocktopus.gcode file from within Simplify3D? S3D embeds all of the settings at the top of the .gcode file. Thanks!

Hi Doug,

Sure I can post the remainder of the settings no problem. I am currently on holiday and back on August 31st.
Once I get back I will post the setting details.

Cheers,

Dave

Hi Doug,

I am now back from holiday and have sliced a Rocktopus with Symplify3D using the PETG profile. The Gcode should hopefully be attached.

Let me know how you get on.

Cheers,

Dave
Rocktopus.gcode (924 KB)

Sweet, thanks! I will give this a shot. I have a decent profile in Cura working well on larger, more monolithic models. As long as there aren’t too many retractions/stops/starts, etc.

I’ve just been experimenting with some PETG as well, must say i like it over ABS, no lift at all for me, sticking like glue to the bed and no smell!

Couple observations though, I sourced through a local supplier and their advise was to print theirs at 195-225c at 210-225 i had what i thought was stringing, actually what was happening is that PETG is so tough it was being stretched by the print head and not adhearing to the previous layer that well on occasion if the head got just that bit cooler. So my “stringing” was actually mid-print delamination. Note i had the fan running and this kind of “stringing” was thicker and would come out the side walls of prints as well, similar to blobbing.

Small parts I didn’t notice as the stuff is so damn tough. Taller prints, snapped apart with a small amount of effort.
Once I got above 225 it disappeared and more traditional (very, very fine) stringing showed up until i got retract right (2mm+ retract)

Next, setting head temp to 230c with print speed set to 3000-3200mm/min meant that the head would cool back down to 218c when doing a lot of infil. Slowed it down even further 2800mm/min and it seems more stable now (Love octoprints graphs!)

Next bed temp above glassing (glassing for this make/brand is around 85c) means you really need to work the print to get it off, ended up around 80 for smaller prints, 75 for longer prints (Bakes on well). Still an effort to remove but much easier. No first layer issues so far

Finally additional cleaning required as mentioned elsewhere, nozzle head can gum up post print affecting next print calibration on the 6, noticed it less once I got my temps right but still required manual cleaning to ensure next print would work ok.

Anyhow hope it helps someone troubleshoot if the label was wrong like mine.

I’ll keep experimenting and get this dialled in right but persistence is showing this stuff is much easier than ABS.

Printing out a spares set out of natural/clear of gears etc. as we speak, long bearing holder will be interesting see if it comes out strong enough.

Final comment, I think for more artistic stuff like busts/vases etc i prefer PLA, just a little easier and faster due to lower heat requirement etc. Structural, defiantly liking the properties of this stuff and despite a hard start it’s working well for me

Good work - excellent contribution to the PETG vs HIPS thread :smiley:

I’ve been experimenting with PETG as well and like it for the shiny finish. Also, the strength does seem to compete with ABS indeed. I’ve bought some reels from http://www.real-filament.com/ and they communicate conflicting temperatures. The box says anywhere between 190-245, the site says 230-250. In my experience 240 was too hot, lots of bubbles and accumulating crud during print because of filement overflowing, also this caused filament grinding (getting stuck above the hotend as I understand it).
I ended up printing at 220 and bed temp 40. I also speeded printing up somewhat in hope to prevent the crud forming. Had perfect bed adhesion for larg(ish) surface print using these settings last print.

My (Mini) Cura profiles (high speed/medium quality/high quality) are a constant work in progress, but if anyone’s interested I could share them?

I haven’t played with HIPS yet, that’s coming soon.

HIPS is very much worth playing with …

I started with ABS but found any large structures in the open TAZ5 tended to warp or de-laminate. Personally, I found
HIPS much more forgiving and can also be vapor polished using MEK rather than acetone.

PETG was a great alternative to ABS. Just as strong if not stronger but without the shrinkage issues. OK, it might be prone
to slight stringing but this is easily fixable with the correct temperature and retraction settings - to be honest I didn’t encounter
much in the way of string and any that occurred was very fine and simply brushed away.

Dave

Ive been printing with 3dextech cf petg. Due to the carbon fiber there is a lot less stringing (I believe that is why)

ive had horrible results with fast printing, im currently getting really strong results with the following settings (simplify 3d):

265c printhead (E3d v6)
70c bed
25mm/s print speed
125mm/s travel, could be faster but not necessary.
2mm retract
40mm/s retract speed
2.5mm wipe
1mm coast
100X travel detour factor
20% fan speed starting on 5th layer

I run a separate process If I need support, everything is the same except:
reduced extrusion multiplier by 10%
fan 100%

Also something that helps greatly with nozzle crud:
silicone cover for hotend (A must have)
also use infill patterns that do each pattern on every layer aka triangle in s3d. this helps because the laid down filament likes to slightly ripple when it crosses a previous path, if it does each path on each layer this doesnt happen.
And lastly print slow. Travel Fast.

This is my start code: (you probably shouldnt use the mcode parts, unless you have my exact setup)
M92 E507
M301 P121.53 I22.89 D161.29
M205 X35

G28
G1 X0 Y10 Z3 F6000
G92 E0
G1 F200 E6
G1 X0 Y20 Z6 F6000
G4 P1000
G92 E0
G1 X0 Y0 Z0 F6000

This gives me a nice purge of filament right before the start of a print, due to how much petg likes to leak.
I have pid/estep settings because I swap between hexagon and e3d hotends and wades style/bondtech filament drivers.
I also have the M205 in there for when switching between direct and bowden extruders.

Great input to the thread !

Going to have to try some of that carbon fiber based PETG !

Dave