DIY electrolytic polisher
I have a very useful device to present in the laboratory of dental prosthetics for the final processing of metal structures ("flash").
3D printing made it possible to produce the most closely matched, necessary elements of a magnetic stirrer, adjustable rod clamps, ventilation ducts and a front panel frame inclined at an angle of 60 ° to the base plane for easy reading of displays. I made the projects using FreeCAD. The slicer is a SuperSlicer. I used PLA filament from Plast-Spaw. The layer height is 0.2mm.
The whole thing is closed in a Hammond housing made of extruded aluminum.
Smooth regulation of current intensity and step (encoder with button) regulation of working time in steps of 30 seconds, pause function, status LED indicator and sound signaling of the end of the process.
Current regulation:
https://leon-instruments.blogspot.com/2010/03/zasilacz-regulowany-20v-5a.html
Ammeter:
http://danyk.cz/avr_adc_en.html
Timer:
https://arduinoplusplus.wordpress.com/2016/02/27/led-display-relay-timer/
Stirrer PWM controller:
The electrolyte I use is ELEKTROL by Chema (composition: ethylene glycol, sulfuric acid, hydrochloric acid).
The anode is a polished piece and the cathode is a lead sheet formed into a cylinder. It can also be a copper sheet.
An 80 mm fan works as a stirrer. 10x3 mm magnets. The "jumping" stirrer in the jar contains 3 pcs. 4x4 mm cylindrical magnets.
The pendant with alligator clips is connected to the power cord by means of a connector from an electric cube hidden in a printed clamp.
Instead of a mains transformer, I used a 24V 6A modular power supply.
The working voltage is approx. 16V.
STL files:
https://www.thingiverse.com/thing:4869317
Comments
A stirrer with these 3 neodymium mates does the same? Is it for sale? If so, how did he sink the magnets and in what material? [Read more]
Nice made, but I have concerns about the air vent at the top of the case. I know that if you work carefully, you shouldn't spill anything, but there is a risk, and there is power inside. [Read more]
Alone. An element with magnets, printed with PLA filament, fitted to the fan "press-fit" and glued with poxipol. Then I heated the places for the magnets with a propane-butane burner and flooded them.... [Read more]
My colleague did not understand the question, or I asked incorrectly, so I will clarify it. I mean the stirrer in the vessel, as my colleague called it "jumping in the jar" made of 3 cylindrical 4x4 mm... [Read more]
forgive :) Printed two halves of a cylinder with a cylindrical recess inside for magnets. Both halves stuck together with poxipol. [Read more]
And that's what I meant :) I have been playing with 3D printing for some time, but I am wondering, firstly, whether such a printout will be tight (with you a magnet can corrode) and secondly, whether... [Read more]
Good question, but I must clarify that the stirrer element, in which the cylindrical magnets are closed, is made of PET-G. And I did so that first I pressed glue into the printed halves of the stirrer,... [Read more]
Where did the idea for such a useful device come from? In my opinion, it will be useful not only in dental prosthetics, but wherever you need to polish something irregularly shaped. Are you professionally... [Read more]
Thank you for your words of appreciation. I am a dental technician by profession. I used to make a few such devices, but back then I had no idea about 3D printing and they didn't have a stirrer. A... [Read more]
Why such combinations? Ready-made laboratory Teflon stirrers are available. They don't cost a fortune, chemically resistant Teflon. https://obrazki.elektroda.pl/3051506100_1622327451_thumb.jpg [Read more]
Cool equipment, tell what metals / alloys this electrolyte is suitable for, because on the manufacturer's website there is a note: And I would have a few details to polish, where the main alloy... [Read more]
Different metal alloys require different electrolytes and bath parameters. For copper, the electrolyte component is phosphoric acid, chromic anhydride and thiourea. Unfortunately, I have no experience... [Read more]
The current is shown on the display, what is the voltage? [Read more]
For chromocobalt around 15 ... 16V, so I took 15.8V. [Read more]
Thanks for the answer, and what current should not be exceeded? [Read more]
For dental technology purposes, 3.5A is ideal, but the current depends on the polished surface. You can experiment with the value of the current and the time. [Read more]
In all electrochemical processes of this type, the current density per unit area of the electrode is important. So the ampere alone is not enough ;) [Read more]