Lithophanes in PETG?
Has anyone here printed lithophanes in PETG, namely Prusa Signal White? I just discovered lithophanes and am converting to PETG. Research so far has everyone using PLA for lithophanes and naming brands for best visual quality.
My biggest concern with PETG is burnt filament inclusion in an all white print. I also don't know which white PETG may give the best looking lithophane.
I have no white PETG or PLA right now.
Using white PLA seems like it would lead to less frustration, but where is the fun in that? I do like the physical properties of PETG.
What do you all think?
RE: Lithophanes in PETG?
I've recently switched to Hatchbox PETg white for my routine white prints. I've had no blobbing issues. IMAO, much of the blobbing issue with PETg comes from 'boogers' clinging to and around the nozzle and dropping onto the print. I have not done any lithos, but I've done windows for model buildings in so-called clear Reprappers PETg with no issues.
RE: Lithophanes in PETG?
@jsw
Thanks! Good to know.
I got dark inclusions from nozzle buildup using Prusa Neon Green. I now brass brush the nozzle before each print. I wonder though if a long print might get enough buildup to cause inclusions.
Of course, my first look at a lithophane was frank-d5's Moon Lamp. An 8 inch diameter spherical moon, a 45 hour print! I think I'll start smaller!
What PETG settings do you use jsw that you would say are most important? About all I have that could be better are some wispys.
RE: Lithophanes in PETG?
I use almost exclusively the defaults.
The only thing I've changed is the non-print move speed, and that's due to an off-and-on issue I've noticed and nothing to do with the type of filament.
RE: Lithophanes in PETG?
@jsw
Thanks jsw. I ordered some Hatchbox white PETG. I'll report on how it works for Lithophanes.
I've slowed everything down for printing from the Prusa PET defaults except for travel, which I left at 180mm/sec. Retraction to 2mm and left Z hop at 0.6mm. Doing most print moves at 40mm/sec. For the first layer I'm using 10mm/sec.
I'm getting good prints other than some stringing.
I brush the nozzle every print with a brass brush. I have a E3D nickle plated copper nozzle coming so the PETG will stick less to the nozzle.
Worth it for a more robust plastic, in my opinion, than PLA.
RE: Lithophanes in PETG?
"PETg is the new PLA." 😉
Over the past couple of months I've been phasing in PETg for the common color (white, black, gray) things that would be done with PLA.
PLA does have its uses, however. For indoor items, such as model railroad buildings and accessories, it's just fine. The availability and color selection of PLA seems to be wider than the others, particularly in the earth tones and other than the basic 'usual suspect' colors. It's also probably the easiest to print.
However, it also has its issues. Stability at warmer temperatures is its big shortcoming.
It also seems to be the most tricky to get to stick well under some circumstances, particularly when small-footprint supports are used. I would say that over 95% of the bed adhesion issues reported here and elsewhere are with PLA filament. (Of course, I might also say that over 95% of the inexperienced users are using PLA as their first filament.)
I think the bottom line is that PETg is not much more difficult to use than PLA, right about the same price point, and a good choice to keep on hand for basic print jobs.
RE: Lithophanes in PETG?
@jsw
Agreed. I like that PETG gives, has some flexibility, and it comes in transparents! 😀
PLA parts have never felt "right" to me, too brittle. I'm befuddled to find that it is actually stronger than PETG in some ways.
Fortunately, I've only had the one roll of silver Prusa PLA that came with my printer. I've mostly printed quadcopter canopies in TPU. The first PLA canopy failed miserably in a crash. PETG was very new when I was experimenting then.
RE: Lithophanes in PETG?
PLA parts have never felt "right" to me, too brittle. I'm befuddled to find that it is actually stronger than PETG in some ways.
Back in March I printed the gears for a hands-free flush actuator using PLA. I was particularly leery of the pinion gear (below) as it's small and the teeth are subject to more force than those of the driven gear. I expected it to break long before now and I planned to reprint it in ABS when it did.
It's still running fine, even in a wet environment (inside the tank) having done several flushes per day.
RE: Lithophanes in PETG?
@jsw
"hands-free flush actuator"?! You will have to explain that one! 🤣
I can derail my own thread, can't I?
RE: Lithophanes in PETG?
"hands-free flush actuator"?! You will have to explain that one! 🤣
I can derail my own thread, can't I?
Yes, it's your thread, you can hijack it if you wish. 😉 Here's the story. You asked for it. Be careful what you ask for, you may get it. ;-0
To make a long story long.
When we built the new house a number of years ago, the plumber was pushing the 'new high-tech' touchless flush for the toilets, and my wife loved the idea, so we ended up with three of them. Yes, three times the trouble.
They were junk! Actually, to call them junk was to compliment them. They would malfunction in three ways. 1) Not flush when you waved your hand over the target. 2) Flush spontaneously at inopportune times, such as the middle of the night. 3) Cycle continuously.
I was very assertive with the plumber that they stand behind them, so a couple of them were replaced under warranty and eventually they gave up and refunded us the charges for them but let us keep them.
My wife LOVED them, and still does, so for a while I kept changing out the one in the master bath with the one that worked the best (or malfunctioned the least), but eventually the best-working ended up midnight-flushing and finally cycling continuously until the batteries ran down.
She still LOVED the idea, and asked 'is there anything you can do', so I dissected one of them, determined that the trigger circuit was very poorly designed, so I mounted a Raspberry Pi Zero and an ultrasound detector to the rear bracket and used that to trigger the DC motor inside and do the flush. She could then wave her hand in more or less the same place as the original target and it would flush.
That worked quite well for a few years, but finally the motor and gearbox (JUNK!) self-destructed. I probably could have subbed out one of the two still-probably-good (for now) motor-gearbox things, but I knew the same issue would happen, probably sooner than later.
This was last winter right after I got my own 3d printer. I pulled everything out of the case of the unit and mounted a stepper motor inside of it, with the shaft sticking out the original shaft hole. It was very simple to just hook the Pi Zero up to drive the stepper in lieu of the DC motor.
At first I tried driving the actuator wheel directly with the stepper, but it did not have enough torque to reliably lift the flush mechanism consistently, so I printed two gears, a pinion on the stepper shaft and a larger driven gear which I attached to the underside of the actuator wheel.
It's been working fine for several months despite my concern with PLA possibly fracturing under stress. I now have a spool of the PC Blend, so if it happens, that's what I will use for the replacement.
In the photo below you should be able to see the pinion gear sticking out of the case and the larger gear behind the actuator wheel. (Kind of in the shadow, look closely.) Not visible are two magnetic sensors, one for TDC and another for BDC. (The original did have a magnet already on the actuator wheel.)
Programmatically, it's a state machine, with an error state forced if something goes wrong, such as not tripping a sensor within so many seconds.
When the hand is waved, the wheel is rotated to TDC, raising the flush valve. After a pause for the flush to occur, it returns to BDC and waits for the next flush.
Hey, you asked for it! 😉
RE: Lithophanes in PETG?
@jsw
LOL! Gotta keep the Honey happy!
Impressive work I can aspire to!
RE: Lithophanes in PETG?
Thanks.
For a while I thought of writing that up and submitting it to one of the 'maker' magazines, but in searching things, others have made similar gadgets, usually from scratch and more often time using a linear rack type of gearing for more of a simple up-down motion.
Had I to do it over I probably would do it that way. I've already done a rack type gear thing, driven by a similar stepper scheme, for a model railroad platform project (below), and that could actually be repurposed for a flush valve.
RE: Lithophanes in PETG?
jsw, "I've recently switched to Hatchbox PETg white", what white PETG were you using before? How would you compare Hatchbox to what you were using?
RE: Lithophanes in PETG?
jsw, "I've recently switched to Hatchbox PETg white", what white PETG were you using before? How would you compare Hatchbox to what you were using?
I intended that to say that I am migrating, at least somewhat, to PETg from PLA for the common everyday prints using the usual suspect colors. The Hatchbox PETg is the first white PETg I've used, and before I was using Hatchbox white PLA when I could get it for everyday prints. I also had very good luck with an off-brand Ebay white PLA (no longer available) which looked and performed almost identically to Hatchbox PLA. I was somewhat disappointed in Solutech white PLA, as it's obvious that they did not use as much pigment, resulting in more translucency.
I've also had good luck with Prusa(ment?) and Reprapper PETg, but not in white.
In general, I consider Hatchbox to be one of the best, right up there with Prusa(ment). I've also had great luck with Paramount, but with various earth tone and oddball colors and never with PETg. (I'm not sure if they even make PETg filaments.)
RE: Lithophanes in PETG?
Adding my 2 cents...
I have used the Hatchbox white PETG on lithophanes and it worked well. I also tried transparent (not Hatchbox) and that was a failure. I use the same transparent for other stuff and it is great but I think transparent in general just won't work for lithophanes. What I am failing at is recalling why it was bad as it has been a couple of years - I think it was the lack of diffusion so you saw all the layers.
I did not name the transparent manufacture as I like the filament in general and don't want to associate them with my bad outcome.
For jws - simple is better 😀
RE: Lithophanes in PETG?
@jerry-v2
Thanks Jerry!
RE: Lithophanes in PETG?
My first lithophane using Hatchbox white PETG. The back had some stringing and blobs, but I thumbnailed off most of it and am pleased with the print. I made it 100mm tall and used the https://lithophanemaker.com/ night light app to make it. 4 hour print using a speed of 40mm/sec for just about everything.
Oops, looks like the site squished the pic vertically. How does one fix that? Sigh.
