DIY Perks YT channel published this video with very simple and effective way to acetone vapor polish ABS parts with a simple glass container. Finished parts look very good and smooth.
Here is a tutorial video:
This technique uses the fact that acetone vapors are heavier then air and they fall down in a container. Water is used to create an air tight seal.
Micheal, well known for his TestrBot made another useful and easy DIY project that enables you to build ultrasonic vapor polisher for your 3d printed objects.
Here is the project summary:
What's needed is a better solvent application method, and that's what this Instructable is about.
The current vapor polishing methods and their drawbacks include:
Hot treat via boiling solvent in a crock pot or similar chamber (Potentially dangerous and very hands-on process)
Cold treat via slow release of solvent from paper towels in an enclosed container (Very time consuming, can't observe parts during this process.)
Spray canned solvent aerosol onto part. (Inconsistent surface finish, must be done outside)
Dipping parts directly into liquid solvents (Unpredictable/inconsistent finish, Likely over exposure of part)
All I wanted is a machine that lets me quickly drop parts into a transparent container and be able to press 'go' and have the machine produce a predictable finish on its own. I do not want to have to put together a really involved setup that may be a fire hazard, fume hazard, or something that produces unpredictable surface finishes. Essentially I want something as convenient as a microwave. I'm also forgetful so I don't want my parts to be destroyed if I forget that I left them in the machine.
The Ultrasonic Misting 3D Vapor Polisher is the solution to all of these problems.
This key component of this machine comes from ultrasonic humidifier, which uses a piezoelectric transducer (like a speaker) to create a high frequency mechanical oscillation in a liquid. This vibration forms an extremely fine mist of droplets in a fog/mist. The density of the fog is controlled by varying the intensity of the vibrations via a potentiometer.
This fog mist is very dense and wont move far on its own, so I used an aquarium air pump to blow it from the misting chamber into the glass finishing chamber where it can condense on the 3D printed part. This airflow keeps the air moving inside the finishing chamber, which helps produce a consistent finish on the part. The airflow system is open by necessity but we do not want the exhaust air to become a fume hazard so there is a water bubbler on the exhaust to absorb excess solvent. (Note that this only protects you when using water miscible solvents such as acetone.)
Here is the video of machine in action and results of the treatment:
The vapor treatment resulted in a consistent overall weakening of the test specimens. Specimens that had not been treated with Acetone vapor had an average yield stress 24% higher than those treated with the vapor.
Solvents that can be used to polish different materials:
ABS: Acetone
Acrylic: Most Solvents
PLA: MEK or 'MEK Substitute'
PVA: Water
PVC: Most Solvents
Polycarbinate: Pretty solvent resistant
Nylon: Pretty solvent resistant
Polypropylene: Pretty solvent resistant
Polyethylene: Pretty solvent resistant
Stay safe people! Chemicals are dangerous! You can check this chart showing dangerous combinations:
3D Print Tips YT channel posted a video on how to use PVC pipe cleaner that is commercially available to vapor smooth PLA. The cleaner fluid is probably rich with THF (tetrahydrofuran) so it has a similar effect as acetone on ABS plastic. Do keep in mind that this method is probably less effective than using dichloromethane and chloroform.
The procedure is simple, the object is suspended above the heated THF rich fluid and the vapors dissolve surface layers and make them smooth.
Do keep in mind that the fumes are toxic and there is a fire hazard! Heating THF causes unstable explosive peroxide compounds that are carcinogenic.
Here is the PLA part after the process. You can see that the surface is polished and shiny looking. LAyers are almost not visible.
Here is video showing the setup with few simple supplies like copper wire, mason jar and heater:
You can read the first post about THF polishing and smoothing here:
MetalicaRap is an open source DIY 3D metal home solar cell printer, based on the principles of electron beam welding and vapor deposition. MetalicaRap is currently in the early design and development phase.
The goal is to have affordable home-manufacturing of solar cells, key electrical parts and milled-quality metal parts. MetalicaRap has a very ambitious mission to bring down a price of home solar power system from 10.000 euro to 400-500 euro range by printing it. If this projects is successfully developed it could make a major revolution in DIY 3d printing, solar power and DIY electronics.
This project is too big and complex to cover in this post, I'll follow it and update it but be sure to check the project homepage for much more information.
MetalicaRap
Proposed technical characteristics:
A build volume of about 30cm x 30cm x30cm (prototype will be 24cmx24cmx24cm as this is min that can still print babies)
Produces finished parts +/- 20 µm over 20mm
Finished parts should be the metallurgical equivalent to wrought iron milled metal parts(full strength, >98% density)
The printer is largely self reproducing(i.e. it can print many of its own parts)
Single Phase electrical supply
Minimum consumables beyond metal powder (avoiding need for e.g. argon gas would be an advantage for later designs)
Cost for parts which it cannot itself print plus the raw material for printable parts is less than the cost of a used car (self replication plus self build kit may reduce the price by approximately 100 times i.e. from the existing price of a metal 3D printer or solar cell plant; 1,000,000 euro price tag,to 10,000 euro self print/kit price. historically the plastic printer went from 30,000 euro commercial price to 500 euro in 2009 via this approach)
The build-rate can be slow i.e. 0.2 kg per hour.
Max height should be 2.4m so it can fit in a home. ( first/simpler to construct prototype will be taller than this until we know how much we can bend beam while maintaining spot size, the bigger the bend the shorter it will become)
Shape and size of vacuum chamber and electron gun power rating should be suitable for Solar Cell Printing(300W).
Since it is a high tech advanced design with many sophisticated technologies integrated in single device, here are some advantages and disadvantages:
Advantages of current chosen design approach
Fully functional parts directly from standard metals
For most parts it may offer dimensionally finished metal parts IT grade 7
Good metallurgy on all common metals (Melting process rather than sintering process ensures near 100% of solid material)
Closed loop system
Self measurement of finished part tolerances.
May offer automatic self correction (subtractive machining steps during build process and feedback with compensation used in the additive process).
Eventual additional Benefits;
Can print thin film CIGS Solar cells in existing 10−4vacuum chamber with existing electron gun. Will be able to self print additional required parts for solar cell printer.
Can create its own metal powder from scrap metal.
Can finish the refining process for titanium metal by melting titanium sponge, which may lead to a 25 fold reduction in the titanium price.
Disadvantages of current chosen design approach
Vacuum chamber needs on going maintenance.
Given the quantity and quality of metal/materials used in 10-4 torr vacuum chamber construction they may have high cost or be hard to obtain. (Limited outgasing required)
Difficultly in managing metal powders, indicated by the need to have layer error correction, Problem area's including; powder layer flatness, metal meniscus blob formation, metal powder trapped in work piece (i.e. designed internal closed cavities, designed internal porous or honeycomb structures most likely impossible without additional processing or work on the part after printing).
Quality Control may be a hurdle to overcome - on the fly heat treatment process development (to overcome residual stress present in the first few layers) may be desirable but optional. Layer by layer temperature measurement is one way for metallurgical quality assurance. Currently multiple printed and tested tensile test samples are used to prove most processes. This is a problem in general for additive manufacturing of all sorts at present.
Adequate surface finish may require post processing, depending on the purpose of the part.Later by the addition of argon we could do electronbeam polishing.
Here are some great tutorials on how to polish your 3d printed model with acetone vapor. Some results are just awesome! Stay safe.
The process is pretty simple. Get a large glass jar, put it on a heated build plate, add a tablespoon of acetone, and crank the heat up to 110C. Acetone vapor will form in the jar and react with any printed part smoothing out those layers.
