In this guide you will learn how to make fast printings and yet get a high quality 3D Printing finishing, Using Acetone and a humidifier
With this method you can print super fast with low resolution layer height and yet get awesome results on ABS! CHECK THE PICTURES!
Comparison between final quality! time to print also has a huge difference
Are you printing in 0.1mm layer height to get “medium-low” quality prints?, you should know that you can do better!. you can get awesome results printing really fast! Please note that there are two ways of doing it. ABS will work better with ACETONE! and PLA works better with Ethyl Acetate or Tetrahydrofuran (both dangerous if not properly used).
How it works?
There are a lot of methods to smooth out parts, and the best so far is acetone smoothing, There a few methods to do it, like:
- Cold acetone smoothing: Works, but take a long time (up to 24 hours) to finish the smoothing, this has a good quality! and is not dangerous¹ but it needs some guessing about the time. makes it a bit hard
- Hot acetone smoothing: Works fast, about 20 minutes to finish, but this is dangerous and can explode/burn. this method also “drinks” acetone, also, requires a heat source (heated bed, gas, anything that get 70ºC)
- Ultrasonic acetone mist smoothing: Works fast, there is no danger¹ of fire and in this method you can save up to 80% of acetone. the final result comes with a awesome quality
- TetraHydroFuran vapor : Works fine for PLA, is only a bit dangerous, but using an ultrasonic misting gives better distribution of the chemical
- Ultrasonic TetraHydroFuran mist smoothing: Works faster, in this method you can save up to 50% of tetrahydrofuran. and the final result comes with a awesome quality
How the mist is made?
Now to the “science” behind it:
- A piezoelectric transducer (resonating frequency 1.6MHz) produces high-energy vibrations which cause the water to turn into fog, how?
- The transducer creates oscillations of high frequency on the water surface. This causes the water to turn into vapor.
- High pressure compression waves are created on the water surface, causing vapor molecules to be released into air.
- Water particles in the fog are of a size less than 5 microns.
- The transducer vibrates causing the liquid to turn into droplets, which vaporize to turn into fog particles.
- Unlike thermal or heat-based foggers, the fog generated by an ultrasonic fogger is cold and wet.
Check the image:
¹ Although the machine itself is unable to make sparks, others things can, you need to careful! we tried to put fire on the mist with a match to see what would happen, and got a huge explosion, since the particles are all in gas form). REMEMBER! you should not inhale ANY mist/vapor of the chemicals! they prove themselves very dangerous to your health. use the device outside or at a ventilated area.
WARNING DANGER AHEAD!
The left image is a common acetone flame, the right one is a mist explosion, there will be a much powerful explosion, so please be careful!,
Now that you know the risks, and agree to make sure that you WON’T let fire near it. we can proceed
What will we need:
- A working 3D Printer;
- Pure acetone (drugstores acetone WILL NOT WORK, they are weak and have a lot of oils on it);
- Pure Ethyl Acetate or Tetrahydrofuran (those are controlled chemicals!)
- An ultrasonic misting device (can be a humidifier, a mist-maker for gardens, etc);
- A plastic box that can handle the size of the treated piece
- A metal box for mist making
- One aquarium air pump
- tubes to connect things, can be the same as the aquarium pump
With the ultrasonic device in your hands, you need to get the misting device and find a place for it to rest. for an ultrasonic humidifier you will need to disassemble it and separate the electronic from the misting part. if you got a garden misting, you don’t need to go for this step.
Names that we will use:
- Piezo = the electronic device that will vibrate in a high-speed, break the water and create the mist
- Piezo Board = the electronic circuit board that will generate the right frequency to break the water molecules.
- Power supply board = The electronic board (usually separated) that will provide -12, 0, 5 and 12v to the circuit board. (some boards ony require 12v, but I stepped against one that used those all…)
Extracting the Piezo froma ultrassonic humidifier
These parts can be extracted from a common air humidifier, or bought directly from ebay / aliexpress (it is not cheaper, since it will require also a power supply, cables, coolers…). You will need to extract it carefully, making sure that the cables of the Piezo won’t be damaged (once broken, is really hard to fix it. Supreme soldering skills + special soldering fluid required. Trust me, this is not a common pbc soldering…) DO NOT REMOVE THE PIEZO SUPPORT (Yellow part) FROM THE BASE SUPPORT (black part) to prevent it from breaking or leaking you can put some hot glue or super glue in the hole where the cables come from, preventing any damage. Check the bad guy image:
Preparing the support
After it was extracted you need to make a hole of the same size as your piezo base (the big black metallic support). Because of the o’ring. Is better to use a metal can for it, since it will offer more resistance and a better grip, avoiding leaks. But if you want to see the mist being made (indeed, this is way more cool), you can use a plastic can without the o’ring but adding a good amount of silicone to prevent leaking acetone. Be patient and wait the silicone to get harder (30 minutes is required for moving, 5 hours required to be almost fully dry)
If you use a garden mist maker, you only need to make a suitable hole for the acetone get in, you might noy even need an aquarium pump too, since they have a sealed built-in cooler that will force a small pressure of air through the tube.
Once you made that, you should make a case for it. There is a awesome case model available on this link: DOWNLOAD
Finalizing the assembly
After finishing the assembly of the misting can and the circuit box, we should power it on with water for a few minutes, to check for leaking’s.
You should set-up something like this:
The jars can be the made of plastic, as long that the material is not dissolve-able by acetone. the air pump will make the mist flow from the first can, where the piezo (misting device) is located to the second box/can/jar where the 3D printed part will be.
Now if everything is working as it should, and there was no leaks with water you can proceed to testing with acetone / THF. on the first run, load only a few ml. with the potentiometer on minimum, wait a 2 minutes running like this (so we can be 100% sure that the system wont leak neither the liquid nor the mist). if is has run smoothly we can finally use our system.
Tips for Timing:
Acetone:
- 2 minutes will only “smooth” the smaller parts and perimeters
- 5 minutes will smooth the parts greatly
- 15+ minutes will begin to melt the inside of the part, this can be useful, but can also destroy the print, you should be careful.
DOWNLOAD FILES FOR THIS HERE –> Click here
F.A.Q
Is this dangerous? YES. and should be done outside
This really works? YES, but only with pure chemicals,
Drugstore acetone will work? NO. they wont.
Sources
http://www.thingiverse.com/thing:1264391
http://www.instructables.com/id/Ultrasonic-Misting-3D-Printing-Vapor-Polisher/
Build Your Own Ultrasonic Acetone Mister For Smoothing Your 3D Prints
Really interesting, might have to try it one day. I’ve been wanting to smooth my 3d prints for a while now. Thanks for the article!
Is there another process that does not involve the risk of an aerosol pipe bomb in your house? Acetone Vapor is one of the reasons I do not print in ABS
Maybe we should make a follow up on fast 3d printing.