A friend and I designed and printed a case for a Analog RGB Component Adapter for Apple II GS (http://tulip-house.ddo.jp/digital/english.html). This is the second thing the I have done from scratch and this one turned out great.
I have wanted to make an electric motor from scratch for quite a while now. But instead of just making a motor and hooking it to something like a fan I had an idea. What if the motor was integrated into the fan? I tossed around some ideas putting coils on a propeller blade and got hung up on making the brushes and commentators. I finally decided on doing a squirrel cage fan or if you want to get all scientifical a Centrifugal fan http://en.wikipedia.org/wiki/Centrifugal_fan.
With a bit of magic (sure come call it 3D printing) here is the rotor/fan wheel assembled with 30 turns of magnet wire wrapped longitudinal around each one making a total of 10 coils.
My plan for the commentators and brushes did not quite work out (this is prototyping after all) so I decided to redesign it and make it bigger and glue it on for now. I will reprint it in one piece once I get the design squared away.
Moving on to the all-important housing which I am still designing. I got the basic shape but I am still thinking about how to design the brushes mount and still print the thing in just two halves. Here is the basic shape I am looking at more to follow once I finalize the design and print it out.
The original Nanino is licensed CC-BY-NC-SA, this one is also:
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unsupported License.
Since I have now created one of these with success, I offer to the masses my modifications. To summarize what I have done.
- Original (where I got it from) http://www.meatandnetworking.com/projects/nanino-upgrade. I actual original came from http://vonkonow.com/wordpress/2012/10/nanino-the-diy-friendly-arduino/
- I added a 5v voltage regulator and supporting caps.
- I added a 2 pin header for input on the unregulated side of the voltage regulator
- I made the board two sided. Previously the traces on the top were wires. It will still work as a one sided board if you desire.
- I added copper fills to the entire board.
- Added registration marks for aligning the top an bottom
- Added the name and version as a copper fill. I used version number 5 arbitrarily for my own tracking purposes
- Standardized all holes to size #65 for easy drilling
- Increased all pad sizes to .075 for easy soldering and to resolve pad lifting issued when soldering
Please enjoy my modification and maintain CC-BY-NC-SA. Thanks!
Success!! Its a working Arduino!!! I soldered all the components on the board. It took me a bit to figure out which components are which since I do not have the silk layer and its slightly different from the original which has the values for the components. I also have a few extra holes that I am not really sure what they are for. I connected up my FTDI basic and uploaded good ol’ Blink and low and behold the GREEN FLASH OF GLORY!!!
I must note that the solder did not flow up to the top pads like a normal board with through hole plating. This is not necessary on this board since it is mostly one-sided. It does not have the mechanical holding on the components but I will try not to hang any weights from them. I also did not solder all the headers on yet because I wanted to give it a try and it was getting late. I will finish it up tomorrow.
I did another attempt at etching the same PCB from the previous posts. I did a few things differently this time and got different results some good some bad.
First I reworked the schematics. I increased the pad size of all holes to .075. When soldering some test legs to the previous etching I did we found that the pads detached from the board. Hopefully the larger pad will prevent this. Also I did a copper pour over the entire board to reduce the amount of etching that needs to take place. I did this mostly to save on enchant but it also seem like a good idea. Also as I found from the previous attempt that when printing on the transfer paper the top, which has the name of the board and version, should be mirrored when printed (instead of mirroring the bottom). That way when it is transferred it will read correctly. I also added registration marks to the print for aligning the top and bottom.
Second, a friend found a great deal on a HP Laserjet 1018 at a HAM fest for a whopping $5. No really, just five whole dollars that is it. Since we had problem printing on the paper we needed another printer and this one worked great. It printed fine on the toner transfer paper and it transferred cleanly and completely.
Third I modified slightly how I did the alignment of the top an bottom. Unfortunately I forgot to take pics to help explain the process (I will try to do better next time). Basically what I did was to take a scrap piece of PCB that is in an “L” shape. I took the top print (cut to approximate size) and taped it to the “L” scrap. I next used the registration marks and center punched and drilled a hole through the board. Next I used the holes to align the bottom print using the registration marks and shining a light through the paper. I then slipped the PCB I was going to tech into the “pocket” and taped the prints to the board. Finally I removed the scrap. I realize that this is a bit difficult to explain an I promise that next time I will snaps some pics. Ultimately the alignment is spot on and I am very happy with the results as you will see in the pics below.
So far so good, now what? Well apparently I didn’t read my lessons learned from my previous attempts and I forgot to rinse the board after doing the transfer. This made it take forever for the board to etch. Even longer that before. I ended up leaving the board in the solution for 45-50 mins. This cause other problems it seems that the acid got through the toner an started to pit the copper pores. It does not appear to have adversely effected the functionality of the board but, it does not look a nice as it should. Also during the etching phase I learned another lesson. I was placing the PCB in a zip lock with the ferric chloride and this tended to leave bubbles and places where there was little to no solution. I do not think that I will use this technique again and instead just place it in a tub.
So without further adieu
Final thoughts on the second attempt. First I should remember to read my lessons learned so I do not repeat the same mistakes. I also think that I am at the stage where the board is usable and I think I will solder components to this one. Its not to the point where I am entirely happy with the results but I think that I am not too far away. I am going to make at least one more of these boards for a friend and I am sure that that one will be the best one yet.
Finally some success!!! I was able to successfully etch a PCB this weekend. I followed many different tutorials (which you can find by asking Google) and this how I did it.
- Printing the schematic.
- I purchased Toner Transfer Paper http://www.amazon.com/Toner-Transfer-Electronic-Prototype-Sheets/dp/B00B0ZDXB2/ref=sr_1_1?ie=UTF8&qid=1364912557&sr=8-1&keywords=toner+transfer+paper
- I used DipTrace http://www.diptrace.com/ to print the schematic
- Several printers did NOT work. I think that you may have to use a black and white printer only
- I got some copper clad board http://www.radioshack.com/product/index.jsp?productId=2102495. And cut it to approximately the right size for the PCB that I was making. In the future I don’t think that I will cut the board until after I do the transfer. This should reduce the waste board.
- I then thoroughly cleaned the board using acetone and paper towels making sure not to leave fingerprints on the board once cleaned
- Next I cut the schematics (top and bottom) and taped two sides together to make a “pocket” for the copper clad board. In retrospect this did not align the two sides correctly. I think this technique will work but I need to use a spacer made from scrap pcb so that the alignment is correct (see picks below)
- I place the PCB into the pocket and ran the whole thing through a laminator http://www.amazon.com/Swingline-Fusion-Laminator-Warm-Up-1703074/dp/B009FFYIJA. I didn’t really know how many times to run it through so I ran it through about 15 times.
- Surprisingly I did not have to soak the paper it simply lifted away and left the toner on the paper. I am thoroughly impressed on the sharpness of the toner on the PCB.
- Next I placed the PCB into a zip lock bag and poured in some ferric chloride http://www.radioshack.com/product/index.jsp?productId=2102868. I then place the zip lock into a tub of hot (from the tap) water. This took longer than I expected. I estimate that it took about 30-35 mins. Although I did remove the board twice and rinsed it to check the progress.
- Once it was fully etched I remove it an rinsed it in water and dried it with paper towel.
- Next I used Acetone to remove the toner which is the black stains you now see.
- Then I placed the PCB into another zip lock and poured in some Liquid Tin http://www.amazon.com/dp/B005T8PE4A/ref=biss_dp_t_asn. This only took about 3 mins. And when it was done I rinsed in water again. I also carefully poured the tin solution back into the bottle when I was done to reuse it later.
- Finally I used a Dremel Drill Press http://www.amazon.com/Dremel-220-01-Rotary-Tool-Station/dp/B00068P48O/ref=sr_1_1?ie=UTF8&qid=1364914163&sr=8-1&keywords=dremel+drill+press and a #65 (.035) http://www.amazon.com/gp/product/B000TY190C/ref=oh_details_o00_s01_i00?ie=UTF8&psc=1 drill to dill all the holes. Used http://www.amazon.com/gp/product/B0000DD2N3/ref=oh_details_o00_s01_i03?ie=UTF8&psc=1 also to hold the tiny drill.
This was the first time I did this so I do have some lessons learned:
- When I printed the schematic I mirrored the bottom side of the PCB. This is necessary to match the top and bottom. The problem is that put the name of the board and date on the top of the board (copper pour). This made the words mirrored. If I had mirrored the top and not the bottom the words would have been correct. I will do this in the future.
- The top and bottom alignment we off significantly. This is apparently the hardest thing in the whole process to do. I think I will try using a spacer out of scrap PCB when I make the pocket. If this does not work I may consider drilling a hole or two to match the top and bottom.
Ultimately I had fun doing this which was the whole point. This was a bit more challenging that I had previously though (as my previous posts indicated) and I learned quite a lot. I will not use this first board since the top and bottom alignment is off but, I will etch another just like it (with improvements) and assemble it. I have passed along this board to a friend and he is going to try soldering legs to it to see how it behaves.