Time to put it all together. First, i had some pieces of wood cut into sizes. Two chipboards will be screwed in a T shape. That will be the main chassis. Three other smaller pieces will be glued with Lackleim to make the electronics pit. Lackleim is a very strong and very fast acting glue for wood. It has free time about 6 minutes and 80% actuation within the first 45 minutes. Moreover, lacklime can glue on melamine surfaces.
The boards are cut-to-size
First, two chipboards are screwed in a T shape
The other pieces will perform the electronics pit and are glued with lackleim.
Then, with a narrow long piece of acrylic glass, i formed (using the heat gun) the basic cover shape. Using this piece, i marked the bending positions on a larger piece of acrylic glass. This was the most difficult part, to bend this wide -about 150mm- acrylic glass. I used the heat gun in lower temperature, because if the acrylic glass is overheated, the surface is destroyed. When bending, i had the original formed narrow plastic piece for guide. After each bend, i was placing the piece on a flat surface to ensure that the edge of the piece belongs to a flat surface.
With a narrow acrylic glass i formed the main form
Using this formed piece, i marked the bend-lines on the big transparent piece
While bending this piece, i used the original formed narrow piece as a guide
To ensure that the bend is done correctly, i placed the piece on a flat surface.
This is the result so far:
The acrylic glass was fixed with screws on the chassis. To have the tank fixed in position, i used a sticky rubber. I sticked it all around inside the tank base. At the bottom side of the base, i cut some pieces of hose heat insulation. Next week i will visit a hardware store and provide myself some flat insulation to replace these ugly tubes. But until then, these tubes will do the work.
I used a rubber piece to fix the tank in position
Some pieces of heat insulation will avoid vibrations and noise
The result so far
Finally, i placed all the electronic staff inside the electronics pit. For the PCB, i made an L base with thick acrylic glass and crewed it on there using 30mm spacers. Two switched will control the etch bath. The first one will turn on the heater and the other one the agitator:
The new etching tank is 4 times faster than the old bowl-in-a-bowl method of etching.
Well, i suppose that the etch tank is ready. I did a test run with an 80x85mm PCB. The PCB was finished with 4 minutes time. This is 4 times faster than the etch bath i had before, consisted of two plastic tanks, one inside the other. The etching liquid was in the small tank, while on the larger tank i poured hot water to maintain the etching liquid hot. Manually, i was agitating the PCB.
For those starting out making pcbs who want an out of the box solution, tank, heater, bubbler,thermometer have a look at kinsten.com.au $AU65 for the complete kit.
Look up edinborough etch - by adding citric acid to the ferric chloride solution - the copper ions are moved away from the pcb's copper surface much more efficiently than using bubbles.
Also, when I am only making a quick small board, I put the ferric chloride into a conical(erlinmyer) flask put it in a bath of boiling water from the kettle whens it's above 45C pour it into a plastic bowl & drop the board in & move the ferric chloride over the board with a brush.
@Skiwee Yes i do use it quite often indeed. As a matter of fact, this is the setup i use to make all my PCBs and never failed me.
I plan to make a bigger one, like 4 liters or maybe bigger. So i have some questions that maybe you could answer. To avoid flooding the comments board, i have open a thread in the forum. Please visit the following link:
I like the setup, you seem to use it quite often.
In the second video you agitate your etching solution. There\'s no need for that it\'s just copper sediment and waste from previous uses (it\'s best to hand this to your local hazardous waste management/company).
The solution should have a dark orange/brown \"oily\" appearance.
example image; http://upload.wikimedia.org/wikipedia/en/thumb/8/8c/Iron%28III%29_chloride.JPG/551px-Iron%28III%29_chloride.JPG
for more information on chemicals a quick MSDS search on google goes a long way.
Were did you find the air pumb and the heating resistor ... Also an other thing is about the thermistor is PTC or Ntc what you suggest!
Very nice job !! ... i Would like to build one too :-p
Welcomes from Crete!!
the bubbles accelerate the procedure. They do not stick on the PCB, and even if one bubble sticks on it, there will be another bubble to remove it within a moment. The do a great job.
I do not know if a pump could do a better job, i have not test it yet. But i do know that it would be an ugly job to clean it. Copper remains would destroy the pump if not used. It had to be cleaned regularly to keep it clean. And moreover, why risk circulating the messy etchant outside the tank, if the bubbles work that fine?
wont the bubbles stick to the PCB during the process and hence reduce the effectiveness??
since you already used a fish tank air pump, why not a water pump to circulate the solution? if a pipe with holes along the length is made and one end sealed off, that would help distribute the solution even better.
herctrap you are so right. I had totally forgotten it. I had the masters given to a friend to make the video, but he never did it and did not inform me. I forgot all about it. I will search for the masters (although i am sure that i will not find them again) or i will run a new video. thanks for noticing reminding me.
By the way, my goal was to have a video for each project or circuit (and sometimes for theories and experiments). The fact that you noticed that this page should have a video, makes me double happy. This proves 2 things for me: first that people want to see videos of the circuits and the projects (and so my efforts to make them is not useless), and second that people do know that in this site they expect find videos, and that something is going wrong if there is no video in a project. When i upload the video i will post it in the RSS. Thank you again.
At the moment, i etch without ventilation, but i have an old vacuum that i will convert to ventilator. I really had no idea that rust could occur, although now it sound normal to me! I was considering the ventilation for health reasons only. Thank you for the info Vern!