first PCB

[jrz126]

I just etched my first PCB, and the results werent too great, but it's ok because it was my first time. :?

Some of the traces didnt fully transfer, they were near the ends, and I didnt have that big of a 'pour' between the traces and the edge of the board. I was able to use a marker to redraw them, but it wasn't good enough and they were etched anyways. I could have reprinted my circuit and transfered it again, but i would have had to wait until today to do so. (I'm not a very pacient person )

Also, I dont have the greatest cross-slide vice, so the drilling is pretty difficult. Anyone have any suggestions on a good drilling method?

One idea that I have is to set my grid to .1" in my pcb software and line all the holes up along this grid, or as many as I can, a component or two may have different pin spacings. Then after I etch it, I'll take a piece of perf board that also has a .1" spacing and line it up with my holes on my PCB. Then when I drill, I'll use the holes already in the perf board to line up my drill with the holes in the PCB. I already tried this on my 1st board for the DIP's and it worked pretty good (except I made my solder pads a bit too small. Anyone have a better idea?

After experiencing the difficulty with doing a single sided board, I think I might just order the double sided board(s) that I'll need for my roof led project. expresspcb has (3) 3.8X2.5" boards for 59.00 after shipping. I can modify my driver board so that I can use all three boards. (3 shift registers, 3 ULN2803s, a 24 pin header and 3 10-pin headers per board.)
Has anyone ordered from them before, is it quality work? Is there a company that offers better prices? I would like to have the circuit on 1 double sided board, max dimensions of the board are 6.25"X7.25".

 

[evandude]

i've made quite a few boards with the toner transfer method...

the cause of traces not transferring is pretty much always just not enough ironing. if you're using the staples picture paper you can go pretty crazy with the ironing... generally speaking, the more the better.

as for drilling... i HAVE a cross-slide vice but i've never used it... i just do it by hand. stick a block of wood on there and just drill the board on top of that. I use carbide bits, i've drilled quite a few hundred holes so far with no broken bits, so it seems to work just fine. if you have really expensive bits then you might get stuck with some other method... personally i only have about $60 invested in about 80 carbide bits so i'm not that concerned.

as for doing the board on a .1" grid... you could... but I think that would severely limit your board design... i know on most of my boards i could never do that without greatly increasing my board size.

my main problem with the toner transfer method right now is the traces/pads/pours expanding outward and touching as they melt. makes for a lot of very careful scraping to separate traces. but that's mainly because i am constantly pushing the limits to see how small i can get everything, and how close together i can get everything. so far i've had decent luck with .012" traces and .016" isolation on the pours, using the crosshatch fill... now i'm slowly reducing the toner volume on the print to reduce the "blobbing" problem.

 

[Russlk]

If your pads have a hole, it will guide the drill bit. I drill holding the pcb by hand. I use the toner transfer method, on prepasted wallpaper, and heat it in the oven.

 

[DirtyLude]

I was having trouble with the edges of the PCB as well, until I realized that in the process of cutting the copper clad, I would create a bit of a raised edge. It makes it so the iron isn't able to press down on the flat part by the edge because of the ridge.

I started filing down the edges of the board to make sure nothing was raised and it works perfectly now.

I just created a perfect two sided PCB last night. Everything lined up great, and I drilled all the holes. It wasn't until I started soldering stuff on that I realized I mirrored everything the wrong way. Beginners mistake.

 

[evandude]

ouch. yeah filing the edges is a definite must. for anyone trying a 2-sided board for the first time, i suggest this method:

drill out a few of the holes on opposite corners of one of the toner transfer sheets. iron it on one side. drill out those same holes, through the board. now drill out the same holes on the other toner sheet, stick some pins through the holes in the board, and then you can run those pins through the holes on the second transfer sheet to line it up. go over as much of the board as you can with the tip of the iron to "tack" it in place, and then you can pull the pins and finish ironing the second sheet. then you can continue as usual removing the paper/etching/etc. worked great for me, i i made a pretty intricate 2-sided board a while ago and it came out just about perfect.

 

[DirtyLude]

The method I use is to put the paper back to back and shine a light threw it. Line it up perfectly and then tape two of the edges of the paper so they can't be misaligned. Then you can put the two sided board in between and it's already aligned on both sides.

It makes it much quicker. You can iron both sides on at the same time and no pre drilling is required.

 

[evandude]

hmm, i like that idea as well. seems to me it would work best if you leave a wide tab of extra paper on the side you are taping on, to minimize any effects of the thickness of the board on getting the two halves even... any thoughts? I might try that method next time i make a dual-sided board, actually. my drilling method works pretty well and is nearly foolproof, however it does take quite a bit of time and effort to do the setup...

 

[DirtyLude]

Yes, you need to either leave a 2 or 3 inches of extra paper around the edge that you are taping down to minimize twist in the paper, or just just make sure it looks pretty even.

Don't try to fold the tape around the edge of the 2 pieces of paper. Put one piece of tape overlapping the edge and put another matching piece down. I don't know if I'm explaining this right, but if you fold the tape over it allows more unwanted flex.

I'll have to redo the board I tried last night, so I'll take pictures, tonight.

EDIT: Oh Yeah, the extra paper between the board and the edge that's taped helps in the ironing as well, since the scotch tape melts if you leave the iron on it.

 

[DirtyLude]

Here's the 2 sided board I made up last night.

It's not the prettiest board I've made, but it worked out okay. I realized too late that the serial connector template I used was for a female connector, not male, so I had to cut a couple traces and reroute with wire.

The match between the 2 sides was perfect on one half of the board and kinda wandered about half a mm on the other, but it was all easily within tolarable deviation.

If you pour copper like I did in Eagle, make sure you increase the Isolate value to give you a little more room for error.

EDIT: Forgot the link: **broken link removed**

 

[evandude]

hey! looks good! i would suggest experimenting with the hatched pour instead of the solid pour in eagle. it just means a lot less toner usage. and, large solid pours get a lot of blotchy areas that etch through and don't look very good. with a hatched pour you dont notice that.

seeing those pics gave me an idea. would you guys be interested in contributing to making a tutorial page for the toner transfer method? I was thinking it would be very helpful, considering how often people ask about making PCBs. Those pics are great, if we got a few more "in progress" pics, like with the paper taped up, and then one with the paper ironed on, and then a few of the various stages of paper removal, and then some of etching, and then some of removing the toner... in other words, a few pics from every step of the process.

I think it would be good to detail that method of dual-sided boards, as well as my drill-and-pin method... and between all of us i'm sure we have different methods for just about everything (for instance, i etch with sodium persulphate in a ziplock baggie, instead of ferric chloride in a tray)
so it would be great to be able to offer pictorial guides detailing EACH of our methods so people can pick and choose based on preference and the materials they have on hand.

 

[jrz126]

I think that would be a great idea. When I was looking to make my own boards, I had to spend a while searching around for different methods, and different techniques. It would have been a whole lot easier if they were all in the same place.

I guess I could contribute my "perf-board" technique for drilling. I was also thinking about that, I don't need all the component holes (resistors and caps) to be on the 0.1" grid, it would mainly be for the Dips which require somewhat accurate holes.

 

[evandude]

I am willing to do the write-up and generate the page and everything if people will contribute "articles" of sorts... meaning sufficient pictures and a little written tutorial to accompany them, for each of the methods.

As far as I see it the sections are

1) generating artwork (ie- a quick tutorial of good "design practices" to use with eagle layout, and some quick info on how to actually get the design onto paper)
2) cutting blank boards - this is sort of optional, but i know i had a bunch of trouble finding a good way to actually cut PCB stock down to size... so we could talk about some good methods
3) toner transfer - tutorial of cutting, positioning, and ironing the toner, including separate tutorials for the taped-paper double-side method, and the drill-and-pin double sided method.
4) removing the paper - small tutorial on properly removing the paper from the board, ie - soaking, peeling, scrubbing, without scraping off any toner
5) checking the board for chipped/missing toner, or traces "blobbed together" and some tips to correct that before etching
6) etching - there are a lot of ways to accomplish this, so we should cover a few different ones that we use
7) removing the toner - ie - chemicals to use (i use lacquer thinner, i've heard of engine cleaners, etc)
8 ) drilling - obviously a couple different possible methods we can cover here too, including using the two different types of bits (wire or carbide) as well as the perf-board alignment thing, etc.

any suggestions? I think basically its just going to involve a couple of us actually snapping some pictures during our next board-making sessions, and doing a little bit of writing. as i get enough info, i can toss it together into a website. each one of these parts would only require just a few pictures and a small amount of writing, so even if you could just snap 2 or 3 pictures the next time you are making a board during one or more of these steps in the process, that would be extremely helpful.

 

[DirtyLude]

Usually I'm much better at getting a clear PCB, but this time it wasn't so great. What's annoying is the one I made that was mirrored, and I had to throw away, was perfectly clear.

I don't mind helping with a tutorial. Collaboration on this kind of thing can just be a mess. So, you're in charge. I can host it if you want. I made up a subdomain.

**broken link removed**

I can PM you with the ftp login if you want it.

 

[evandude]

that sounds great, I don't have any reliable way to host it, so that would work out well. Yeah i kind of figured i'd be in charge. mostly all i wanted from people was pictures and some brief descriptions, which i would then use as a basis for a more detailed tutorial. I could take all the images myself, but it would take a while to make a board using each method, when others are making them occasionally anyway. and of course i also want some ideas for different methods for each of those steps i posted. anything that people have successfully used to make PCBs using the toner transfer method probably belongs on the page.

yeah, PM me the FTP login, i'd appreciate it.

 

[panic mode]

evandude,
it looks like you have been elected... :wink:

DirtyLude,
nice pictures. you have nice hobbies. watercooler project looks cool. a bit more text wouldn't hurt although it's not hard to follow

 

[evandude]

Hey guys, i stuck up some preliminary work on the page

**broken link removed**

let me know what you think... obviously i'm not done writing everything, and i need a bunch more pictures... but I haven't had much time yet.

 

[jrz126]

For the toner removal, I'm going to try some brake parts cleaner when I get home from school on my first baord. That is some strong stuff. I painted some pieces of the interior of my car, they didnt turn out that good, so I just hosed them down with this stuff and it took it right off. (hopefully the copper isnt going to be removed too :roll: )

Let me know if there is anything you want me to do. I'm going to try to think of some of the questions I had while I was researching, etching, ect, and I'll start a FAQ for it.

 

[evandude]

awesome, yeah, anything you could write about the process i'm sure i could work into the page. and of course, if you make any boards in the near future, i'd greatly appreciate if you took some pictures along the way if possible.

 

[DirtyLude]

The brake parts cleaner works fine. You just have to watch, since it's in a spray can. It turns the toner to liquid and it runs all over the place. I use the cleaner and some paper towel or tissue to wipe the board down.