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Post by rockotiger on Mar 14, 2007 21:57:14 GMT -5
I've been admiring so much custom work here on the board, especially that of Jim Brain. I've read a bit about it before, but does anyone have any suggestions for getting started with etching my own PCB's for custom circuits?
Not only would It make my projects neater, but it would allow me to make some of the circuits designed by others who don't necessarily want to mass produce them but do give out the board layouts and source code where applicable.
And its sure to impress all my friends (not really. they don't care about my old computers, but at least they can recognize the Commodore logo)
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Post by Jim Brain on Mar 14, 2007 22:38:08 GMT -5
www.cadsoftusa.com (EAGLE CAD). Free, it's what I use, it's pretty easy to use, many board houses will take EAGLE BRD files directly. Now, as for etching, you can do it yourself, but I use www.custompcb.com. There are tons of houses out there, but I like that Custom PDB doesn't use High Pressure Air Solder Leveling (HASL), they take EAGLE BRD file directly, and they offer a 8x10 panel option. HASL is fine for through hole stuff, but if you get a soldermask on it and then hand solder, the mask will wrinkle, as the solder under the mask on the traces heats up. The panel option is nice if the board is small, as you can get a board for $1.00 or so by packing them on a sheet. Also, the house will put multiple designs on one sheet, which is nice if you're like me and need just a few boards of a bunch of different projects. Rolling your own board etch requires getting the caustic chems, a drill press, and access to a laser printer and an iron to iron on the transfers prior to etching. If the board is really simple, and you have much more time than money, it's worth it, but I have little time and only recently had a drill press, so I opted for the board house. Just note, it's not that hard. I had zero knowledge on laying out boards when I started in late 2004. I'll even check your first design if you want. But, if you want boards like mine, you'll have to skip the autorouter. Autorouting is an art, and EAGLE doesn't have the skill to do it well. All my boards are hand routed. It's just a skill you develop as you lay out boards. Jim
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Post by MadModder on Mar 15, 2007 13:44:03 GMT -5
I don't feel like etching is very time consuming. Print layout onto OH film - 1 minute Cut board to right size - 5 minutes Place board + film under glass + UV light warmup - 5 minutes Expose board to UV light - 7 minutes Develop board - 1 minute Etch board - 5 minutes maybe Drill board - (SMD = no time ) maybe 10 holes a minute 35 minutes for a through hole board with 100 holes. A few minutes more than half an hour. Don't say you don't have half an hour to spare
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Post by thurstan on Mar 15, 2007 16:25:42 GMT -5
I am glad someone has asked this as I also want to get into this. I etched my only ever pcb at school, but i dont have the kit or the room really. Got plenty of SID related boards i want to make!
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Post by Jim Brain on Mar 15, 2007 16:42:58 GMT -5
I don't feel like etching is very time consuming. Print layout onto OH film - 1 minute Cut board to right size - 5 minutes Place board + film under glass + UV light warmup - 5 minutes Expose board to UV light - 7 minutes Develop board - 1 minute Etch board - 5 minutes maybe Drill board - (SMD = no time ) maybe 10 holes a minute 35 minutes for a through hole board with 100 holes. A few minutes more than half an hour. Don't say you don't have half an hour to spare Dispose of caustic chemicals ?? minutes Curse and re-etch because you did not develop long enough. ?? minutes Curse because you mialigned two sided board. ?? minutes Deal with bugs caused by not having plated through vias. ?? minutes. 35 minutes for a 100 hole board after you've gotten good at it. I'll buy that. But, to get there requires a lot more time. 1) Doesn;t sound like fun to me, and I do this for fun 2) Anything time sensitive is taboo around our house, with kids. I can't hold up dinner or changing the baby just to wait for etchant 3) Caustic chemicals and kids are a bad combo. 4) If I took a poll, everyone would tell me to spend my limited time on firmware development, not menial etching of boards. 5) bare ethed boards are like $25.00 to $50.00 for a few boards. I can get 36 or so boards of different kinds for $87.00. Now, I did buy some solid etchant, and I now have a drill press and a laser printer, so I won't rule out trying it, but I think the money I have spent on boards is well worth it. Jim
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Post by Jeff Ledger on Mar 15, 2007 22:25:14 GMT -5
If we could talk a few of you hardware gods into releasing your specs designed for use with some of the cheap prototyping boards, we could forgo the pain of etching completely. <hint> Actually, this is my angle with my getting started with the propeller board. I figure if I can master the language enough to create some interesting designs, then perhaps interesting Commodore addons could be created that only require others following to purchase the same and add the few pieces. Jeff
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Post by rockotiger on Mar 15, 2007 23:42:17 GMT -5
Wow, thanks for the responses! While I had originally intended on doing the etching myself, after looking at what it entails, both in dealing with all the chemicals and having a place setup for it, it seems that having it done by a PCB manufacturer as Jim suggests would make the most sense for me.
Hopefully, when time allows, I'll have something useful to add to the community.
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Post by MadModder on Mar 17, 2007 9:18:38 GMT -5
Well no, caustic stuff and kids don't mix. I don't like it very much either. I have a few t-shirts with small holes in them... ;D Concerning the disposal of used chemicals, I'm not very good at doing the right thing. I just pour them in the sink... The developer isn't that hard on the environment, and neither are the etchant, but the dissolved copper IN it is on the other hand. But I'm too lazy to go to the place they handle that stuff everytime i want to get rid of the liquids, and accumulating everything in a can to have it taken care of less often is not an option. So: Disposal of chemicals = seconds Cursing and re-etching = happened once or twice Misalignment of two-sided boards = never happened bugs related to no through plated vias = none. I mostly do single sided boards If I want a professionally manufactured PCB, I have to order it and have it mailed back. That takes quite som time. If I want a board I want it now. And I do have the time required.
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Post by kaos116 on Mar 17, 2007 16:57:05 GMT -5
There is something to be said for both methods.
Having one of the board companies do it. Pros: 1. It is alot cleaner and safer. 2. They also can do double sided better than me. 3. They can silk screening, tin plate and plate through holes. Cons: 1. Price - 4x6, 2 sided in small quantities(4-10) ~$35 each 2. The wait - most are about 10 business days.
I make my own in about 30 minutes depending on drilling holes. I only use one chemical, ferric chloride for etching. My method of laying the board out is to spray paint them and laser etch off the paint over the copper I want removed. Pros: 1. Price - 4x6, 2 sided ~$3 2. Time (30-45 minutes and I'm soldering) Cons: 1. Chemicals 2. More work. 3. An acceptable board, but not professional quality (silk screen, tin plating, plated through holes)
If I ever sell my work I go with the pro's, even in small runs. Just because they look better. But 99.999999999999% of my jobs are done for me at home.
That's my 2 cents ;D
Side note to having the PCB houses doing it. The software and Gerber files!!!! Don't expect your first submission to be accepted. They will always find an error with the gerber file. Sometimes they inform you quickly. Other times they seem to wait.
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Post by gmoon on Mar 17, 2007 17:49:26 GMT -5
You guys are pretty amazing-- ~170 holes/hour?
I can manage about 50....Guess I need to try some new techniques.
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Post by MadModder on Mar 17, 2007 18:45:51 GMT -5
ehm... 170? If I don't have to change the drill bit, I drill a hole at least every 5 seconds. That is ~700 holes per hour.
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Post by Jim Brain on Mar 17, 2007 22:24:45 GMT -5
Some of the houses will take Eagle CAD BRD file directly, so no need to en GERBER or DRILL files.
The delay is real (I get mine in 5 business days, but that's 7 clock days)
I usually pay $3.00 a board, and $87.00 total when I order. It pays to batch the designs up.
My recommendation is to send away for the first board, even if you have the time to do it yourself. Why? Typically, the first time, you're new at layout, you're worried about stuff, etc. One less variable could mean teh difference between a finished project and a frustrated enthusiast. Then, once that "virgin" board is done, you'll know that you can lay out boards, you'll have some experience, and you can then try your hand at a homebrew etch.
Jim
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Post by huckle on Mar 18, 2007 19:14:04 GMT -5
I made a RS232 card just before Xmas using the toner transfer method. I found the whole process VERY time consuming and it took quite a few attempts to get it right, especially since it was a 2-sided board i was doing. I found i had to have pretty wide traces overwise they would break during the soaking/cleaning-off the-paper process. The board actually looks better in real life (honestly. lol) - the picture is highlighting all the flaws in my soldering.
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Post by MadModder on Mar 19, 2007 8:50:13 GMT -5
I have never succeeded with the toner transfer method. I find the UV exposure method simpler. And I have all my layouts sitting in a binder (?) so I don't have to go through the printing exersice again if I want another copy of a previous bord. And for the double sided layout alignment, I do it this way: Put front and back layouts on top of each other on a light table ( is it called that?) and tape them together. Then I put the board in between, and move the "sandwich" over to UV exposure.
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Post by huckle on Mar 22, 2007 18:51:50 GMT -5
As well as the problem with aligning the layout, i found during the 'ironing' process the whole layout sometimes moved, without me knowing, and it was only afterwoods i realised. So i had to go through the whole process again. It did take about 5 attempts to get the above board right! Using your method is obviously alot better, and from looking at your boards looks very impressive. But requires more equipment. I noticed you don't seem to bother with the tin plating? I used tin plating on mine. Do you have any problems with soldering without the tin plating?
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