PC board making - your ideas and experiences?

OakGraphics

Howdy gang - I am looking for cheap alternative ways to make pc boards.
I have used expresspcb.com, and thier free app to create pc boards with sucess, but I am trying to break the 62$ price barrier. :-)

I know we have a topic on milling machines - and that's out of my price range until some sort of cheap kit for say 200-300 comes out of that.

I have done the trace your own pcb on copper clad before with limited sucess, and now I am interested in maybe laser printing pc boards.·· A search of the web shows 2 possible candidates that might be cool:

1: printing pcbs with standard laser printer and not so specialized paper:
http://www.fullnet.com/u/tomg/gooteepc.htm
(seems like a bit of hassle)

2: the 'pulsar' system or 'toner transfer' technique at
http://www.pulsar.gs/PCB/a_Pages/3_Direct_Etch/3a_The_Technique/The_Technique.html

3: Is there a better price per pcb breakdown from another vendor?· I really dont need 3 pc boards of the same thing, and sometimes just 1 is enough for me, so I guess I am a good candidate for making my one-off board - which is why I was wondering if any of you have tried the above methods.

Also - what are your tips?· Should I try to put all the traces on just one side?· Should I make a double sided board and make one side strictly the ground layer?·· What's a cool/easy way to make the circuit design? (i.e. what sofware do you you to plan your boards?)· How do you drill the holes for the pcb?· (do you use a press - or a dremel, or ???)

Thanks in advance, I am sure this will become an interesting topic if it people share thier experiences.
·

Bean

I have and recommend the pulsar system that you mention.
Their "starter" kit is only $100 and includes everything your need execpt etchant, even a laminator !
I can make a single sided board in about an hour.
Double sided boards are tricky and I usually make the back all ground (except around thru holes).

I use autocad for the layout, but only because we have it at work and alot of components are already drawn by our draftsmen.
But it is very flexable. If you want something more for the home user I would try "Quick CAD" (basically a stripped down version of autocad). I think it's about $80.

As for drilling the board, I bought a drill and stand from jameco, but I DON'T recommend it. It is very cheaply made and not worth the money. It works for now, but as soon as I find something better I will stop using it.

Another thing you should get is a product called "Liquid Tin" (JDR sells it). This stuff is amazing. After you etch and drill your board, you simply dip it into this stuff (you don't have to heat it or anything like some other stuff) and within seconds (literially) the board is tinned. This keeps the board from getting tarnished and makes soldering easier.

Whatever software you use make sure you can print your board at at a 1:1 scale on the laser printer.

I have posted pictures of boards made with the pulsar kit here

http://forums.parallax.com/attachment.php?attachmentid=38483

Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012

Product web site: www.sxvm.com

"One experiment is worth a thousand theories"
·

OakGraphics

Thanks for the info Bean, I was looking at the pulsar kit and noted I already have the laminator (the gbc "creative' blue laminator)
So you use the .32 board sizes for your rig? or are you using the older laminator that uses standard size boards? (just curious)

Wowzers! you are doing smt component soldering on these as well. (Something I will have to get into)

Good to hear the pulsar kit seems to work well. I wasent sure if that would work for the 'thin' detail stuff. Thier web site shows 2 traces going between .1" pads - and your board looks very clean, so I guess it will work.

yah - the drill will have to be a good quality drill. I was thinking of a dremel with a very precise vertical drill press or something like that. :-/

I will check out the liquid tin - as that sounds like a time-saver for sure. Quick CAD eh? will have to check that too.

Daniel

Bean

I laminator I got with the kit is blue and says "GBC creative laminator" so I guess it's the same one you have.
I would rather use .062" board, but I plan to make double sided boards by makeing two single sided .032" board and glue them together, so that will be .062" anyway.

I wouldn't even TRY to make my own boards for thru-hole stuff. Just too damn many holes to drill.

So far I have only used the copper board that is supplied with the kit. And it is 1/2 oz copper. They say that 1 oz copper cannot do as fine a line because of under-cutting when etching.

If you note I have a SX48 on that board and the pins are 0.5mm pitch (about 0.020") so the pad are only about 0.010 and they came out perfect.

Let me know if you find a good drill setup... As I have not yet.

The other tinning product I have used it called "Tin-It" and it must be heated and it's a real hassle compared to "Liquid Tin".

Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012

Product web site: www.sxvm.com

"One experiment is worth a thousand theories"
·

OakGraphics

I was on pulsar's web site and they noted a drill press that might be funtional:
http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=81631

It seems to go for $145 - and it might be interesting to get if it saves time.

Was the jameco drill press you used and dont like:
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=26711

it looks pretty flimsy. :-/

Forrest

The best inexpensive home setup I've found so far is the Dremel drill press (about $35 - now discontinued) along with a Dremel drill. There is some slop in the Dremel drill press - but if you decrease the stroke to about 1 inch it works well. They key thing to remember is if you're using Tungsten carbide drill bits (like these sold here www.drillbitcity.com/ ) they are designed to run at 20K to 40K rpm. Anything slower and you'll be snapping drill bits every few seconds.

Bean

Daniel,
Hey that drill press from Micro-Mart looks pretty good and did you see the X-Y table for it ?
http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=82389
I might have to buy one with the X-Y table to attach steppers...

Edit: Ah, the speed is too slow from that drill press.

Yes that is the drill press from jameco. Don't buy it...
Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012

Product web site: www.sxvm.com

"One experiment is worth a thousand theories"


Post Edited (Bean (Hitt Consulting)) : 8/10/2005 11:07:21 AM GMT

quick question

Automation of the screw drive X-Y table may be a bit tricky. Back in my past life, I ran a bridgeport (large metal cutting machine. Because of inaccuracies in the screw drive (slop), you need to run past your point, then back into location. When you "back in" the slop in the screw is eliminated and you get a good position. unless the screw drives are better now, I suspect this technique will be necessary. (easy to code I think)

bobledoux

I've had great luck with the Pulsar system. I use the green film and etch the board using a small piece of sponge--no tanks. It takes about 10 minutes to do a 4x5 inch board.

For software I use ExpressPCB CAD program. See www.robotroom for explanation of process. Software is free.

I'm using .012 traces on SMD boards so they have to be crisp.

Bean

bobledoux,
What do you use to drill the holes ?
Bean.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
"SX-Video·Module" Now available from Parallax for only $28.95

http://www.parallax.com/detail.asp?product_id=30012

Product web site: www.sxvm.com

"One experiment is worth a thousand theories"
·

Yanroy

I use the copper clad etch-with-a-sharpie trick all the time.· I use it for thru-hole (I've never done SMT).· I've never had a problem, and even with all the drilling, I can do a moderately sized board in an hour and a half or so, from the time I start drawing on the copper till I can begin soldering.· I'm very interested in the board etching service provided by www.sparkfun.com, however.· They seem very cheap and only give you a single board (unless you order more).· I think for small boards or a single board, they'd be very cheap.

OakGraphics

Bean (Hitt Consulting) said...
Daniel,
Hey that drill press from Micro-Mart looks pretty good and did you see the X-Y table for it ?
http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=82389
I might have to buy one with the X-Y table to attach steppers...

Edit: Ah, the speed is too slow from that drill press.

I was curious about the drill - so I asked the guys from pulsar ( http://www.pulsar.gs/PCB/index.html·) why they have it in their 'fab lab' (http://www.pulsar.gs/PCB/a_Pages/5_Support/4a_Fab_Lab/Fab_Lab.html ) suggestions area·for PC Board design.· Here is the response I received from them: (thanks Frank for giving us the info!)

According to a "techy" at Tycom (worlds largest producer of bits), I was told that "tip temperature" is what tears up a bit. You DON'T want to use a high speed drill press if you are MANUALLY drilling (ie moving the bit down by hand in a typically slow manner!) This practice while turning at 30,000 rpm "Dremel speeds" will kill a bit super FAST. That press from MicroMark is ideal! I use 4 of them here with my prototyping. It will turn just perfectly fast and your bits won't heat up and die.

Jameco and other have good prices on "resharpened 1/8" shank bits. I personally use .026" for IC pins and "wired vias", .031" for discrete parts and .040" for headers and other "big dog" pins.

Frank [noparse]:)[/noparse]

"

Post Edited (OakGraphics) : 8/10/2005 8:45:36 PM GMT

bobledoux

How I drill my holes:

I drill PC boards using HSS drills in a cheap, $39 Harbor Freight drill press. The runout is horrible. Enco sells 1/32 inch, .032, drill bit for 21 cents each. I mount these is a $7 microchuck that mounts in the drill press. I get about 100 holes per drill bit.

The process: Leave the center hole in every through hole when preparing the CAD drawing. I drill before I remove the toner from the etched board. The drill bit centers on the exposed copper in the center of the hole. Advance the drill slowly so it centers on the copper center. I use a headband $8 magnifier so to get the alignment close and let the drill do the rest.

Because there is precision here, I set the drill press on the dining room table, while wife is gone, and drill under good light and comfortable seating.

I'm a hobbyist. My interest is in occasional boards for my projects. Therefore, I don't want a lot of equipment taking up space with a single function. So I've made no effort to spend money on a carbide drill rig with minimal runout.