4 Items:
1: What was the printer and toner that worked and didn't?
2: For a drill press, I have used Dremel with very good results. I also 
have a 16.5" Delta drill press with 1/16" - 5/8" chuck, and then a 
smaller drill size chuck that can be gripped, but wouldn't even think of 
using that, although the small drill bits with 1/8" shanks can be 
gripped easily. Get the regular PCB drills with 1/8" shanks and short 
drill spiral lengths. The long drill bits with same shank diameter as 
drill size get slight bends, wobble, and eventually break.
3: When making the PCB print image, every hole should have a small size 
hole etched in the copper. This becomes the equivalent of an accurately 
located center punch to get the drill started at the right location. The 
drill will wander to that depression if you get close to the location.
4: For double sided boards, I include a donut at 4 corners, both sides. 
Pin prick through the paper before ironing on the first side, drill the 
4 holes through the board, use pins through the papers and holes to 
align, and iron on the 2nd side. Have had good results with careful 
work, but there are limits to the accuracy. Dips with 0.1" spacing 
should be no problem if there are not traces between the pads. With 
traces between, probably will scrap some boards, probably would solder 
wire across for the a few to be made. :)


solarwind wrote:
> I etched my first PCB today. It came out very well (considering that
> it was the first one I did). I used a mix of different techniques
> which all worked out well for me in the end.
>
> To begin, I made a simple design for a quick prototype board for my
> dsPIC33FJ128GP802. The board itself is very small, just about 1.5" x
> 2.5" (off the top of my head). I had a large sheet of copper clad
> board so I had to cut out the small piece that I would be working
> with. This part was not fun at all.
>
> I printed out my design and traced out the rectangle off a corner of
> the large copper clad board. I then used a utility knife to score the
> sides of my design. It took a while to get deep enough to snap. Then I
> used metal shears to cut one edge of the board. This was an unclean
> cut and damaged part of the large board and slightly warped the copper
> on my design. No big deal. I then stuck the remaining part of the
> board into a vice (with paper towel for padding) and snapped the
> remaining edge. I then sanded the sides with a piece of (metal
> purpose) sand paper. I was then left with a small rectangle of copper
> board ready to be used for toner transfer. I used nail polish remover
> to clean the board. Then I used soap and continued to clean the board.
> Finally, I took some fine sandpaper and scrubbed the board clean. The
> board was now ready for toner transfer.
>
> >From suggestions from my other thread, I tried a different printer. I
> used the same paper (staples glossy paper for laser printers) that I
> had tried before. I set the print quality to the highest setting and
> configured it to deposit the most amount of toner possible. I then cut
> out my design and headed over to my clothes iron. I preheated the
> board by placing a blank sheet of paper of my board and ironing it for
> about a minute. Then I carefully placed my design onto the copper
> board. It stuck instantly. I ironed it for about 2 minutes. (60 of
> those seconds I just left the iron on top and went downstairs to get a
> snack). I didn't do anything special. I just pressed hard (but not too
> hard) and went over it with the tip of the iron. I then filled a small
> sandwich box with water (about body temperature) and dropped my board
> (with the design paper still stuck on it) into the water. I headed
> over to my local grocery store to get some groceries for dinner. By
> the time I came back, the paper was soft enough to peel and rub off
> with my thumb. Some of the toner smudged, but overall, the quality was
> pretty good. The toner had definitely stuck well this time.
>
> Now for the etching part. I took a small dish washing sponge and cut
> out a square about 3" x 3" x 0.75". I poured about a table spoon of
> ferric chloride on the sponge. I put on my vinyl gloves and started
> lightly wiping the board with the sponge. The copper started to come
> off instantly and turned the bright-yellow sponge nearly black. I kept
> wiping for about 2 - 4 minutes and eventually, all of the copper (that
> was not protected by the toner, of course) came off. This sponge
> method turned out to be very fast, efficient, clean and easy. Also
> saved a lot of ferric chloride. I ended up with a very well etched
> board. It was easy to see when it was finished and the etching
> solution worked very fast and etched very cleanly. Then I washed the
> board and inspected it (and admired it). It would have been perfect
> had the toner not smudged. The etching process itself was very clean
> and precise. The only trouble was the toner. I need to find a better
> way to put etchant-resist onto my copper.
>
> I then took the almost-finished board downstairs to drill. This part
> was not fun as well. I drilled about two holes then gave up because
> all I had was a clunky drill and very brittle drill bits. This
> drilling part is impossible without a proper drill press. A CNC
> machine would be ideal (even a crude one would do the job
> sufficiently). So there ya have it. An almost-finished PCB.
>
> Looks like I'll need to find myself a drill press.
>
> To all the helped and gave advice, thank you very much. This process
> turned out to be fun and educational and I leaned a skill that I'm
> sure I'll find very useful in the future. The whole process took less
> than an hour and gave very good results. The results would have been
> perfect if I had a better method to transfer the toner (via laminator
> and a good printer, maybe) and a CNC machine or at least a drill
> press.
>
> What I was most impressed with was the sponge method of etching. Only
> a table spoon of ferric chloride was required and none of that
> heating/agitation nonsense was needed. The process was clean and
> efficient - no spills, little to clean up afterward. So if there's any
> of you still pouring the etching solution into a tub and
> heating/agitating, I highly recommend that you give the sponge method
> a try. It's awesome!
>
> -- [ solarwind ] -- http://solar-blogg.blogspot.com/
>   
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