Announcement

Collapse
No announcement yet.

OT sorta electronics, PC boards and stuff that goes zap!!

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • OT sorta electronics, PC boards and stuff that goes zap!!

    This is OT sorta but related to electronics, PC boards and stuff that goes zap!! There's plenty here who meld electronics with machine tools so I think I'm on a safe OT.

    I needed a custom printed circuit board recently but what a hassle to make them. The raw board material, the artwork, the mystery of getting a good exposure, the developing and etching with nasty chemicals, and finally the drilling with dinky little drills. Expensive and a PITA but them days are gone. I discovered:

    http://www.expresspcb.com/ExpressPCBHtm/Specs.htm

    A printed curcuit outfit that's a one stop shop. They have a number of entry and prototype plans and they GIVE you the printed curcuit artwork for boards up to four layers.

    The costs are not cheap but they are affordable for someone working on a small scale. The price beats the start up price for a few PC board by a mile. I paid $57 incl shipping for four drilled and plated boards measuring 2.5" x 3.8". I crammed four smaller boards onto the area and got 12 at about $5 ea.

    Also included is circuit diagram software complete with a library of digital devices. Naturally everything is live linked. You drag the chip and the connections stretch to follow. The circuit board software is intuitive and has many features. I mastered it well enough in a few hours of fiddling to design my board and send it off via a live link to the ExpressPC. They will be shipped the next day if the design is in by deadline and you will receive them in three business days.

    No connection (no pun intended either). Just a good service I discovered and wish to share with the other wire rubbers.

    There are other prototype PC board services out there but this one seemed to be almost painless.

    Yes, I multi posted this.
    Last edited by Forrest Addy; 05-25-2008, 11:25 PM.

  • #2
    There used to be one of those in our university town but they closed recently. Now everything for our labs is done via breadboard unless its important enough to warrant the trouble of producing our own board.

    Comment


    • #3
      I used them and their software while working on my own stepper drives..

      Kinda wild ain't it? about a few years back that software would have cost a half million dollars. THEN the SPICE software started, I think this is a offshoot.

      I used to do my circuit boards in Autocad, then flip them make a printout, then take it to a print shop to make a photo positive, then expose my own boards,and wash them, then drill them, then solder them.. then laugh like a madman when a radioshack purchased second rate device smoked the whole project.

      The world is limited by only your imagination, and your inept ability to learn new things.
      Excuse me, I farted.

      Comment


      • #4
        I use a house called Advanced Circuits for almost all of my PCB's. They're fabbing 3 boards, 50 pieces each, for me right now. I use PCAD for layout, but they offer their own layout tool as well. www.advancedcircuits.com
        They have a bunch of specials, like 5 pcb's, 60 in^2 max each, 2 layer, 5 day turn, $120.

        I use a house called Screaming Circuits for my small PCB assembly jobs. They're running a 15-board order for me right now. www.screamingcircuits.com

        I used Express PCB a couple years ago but I like the pcb's from Advanced Circuits better.

        Comment


        • #5
          We use a number of houses and have also used Advanced Circuits. Screaming circuits assembled some larger boards for us a while back and did ok. For smaller, quick turn boards I think we are currently using PCBExpress which I think was the PCB partner of Screaming circuits but I could be mistaken.

          We use Mentor/Pads for schematic capture and PCB layout.

          Surface mount stuff is actually pretty easy to assemble. If you are doing any high lead count and/or finer pitch parts, it is worth the money, even on a few up, to get a proper solder mask.

          If someone is doing your assembly for you, be sure that your parts are accurately "kitted" up with reference designators, etc. It's not fun to watch the magic smoke leave tiny SMT parts, some with volcanic like action (small flame, smoke plume). Den

          Comment


          • #6
            Good grief

            When I was doing prototype boards I had to start from scratch, do the art work by hand no such thing as auto cad, then the photo work and then wash and drill. Now it is so easy a kid can do it.

            Forest thanks for the info. I don't expect to do any more of that type work again but if the need comes up I now have access to the easy way.

            Ross
            GUNS Don't kill people
            Drivers using cell phones do.

            Comment


            • #7
              For a quick and dirty prototype (through-hole only) I used to take a CAD drawing, DXF, to my local vinyl sign shop. Get em to cut a mask on the plotter. Stick it to the copper and etch in hot ammonium persulphate. Only prob was tiny bubbles at the edge of the mask. Easily cured by brushing with a plastic paintbush (kids paintbox type) during etch.
              Just got my head together
              now my body's falling apart

              Comment


              • #8
                I started out the same way that David described, until my photographer went out of business and I couldn't get my artwork photographed and high contrast litho negatives made.

                Since then I began using Advanced Circuits for small to moderate quantity prototypes at work. Saved gobs of money and time for the company over their usual method of dealing with their usual sources.

                These instant board companies don't get their work done in China, do they?
                Weston Bye - Author, The Mechatronist column, Digital Machinist magazine
                ~Practitioner of the Electromechanical Arts~

                Comment


                • #9
                  I make my own boards since I have a photoplotter, laminator and the etching equipment. If this equipment wasn't in my shop I would use one of the companies mentioned. It's hard to believe they can do it for so little. I don't think they are getting these boards from China but there are companies in China offering similar services.

                  Comment


                  • #10
                    All of the companies that I have mentioned do their work in the US. Most do offer a Chinese arm for higher volume or longer lead times.

                    There are Chinese quick-turn PCB and Assembly outfits, some have a good reputation, but I haven't used any of them, and I prefer not to.
                    --
                    Aaron

                    Comment


                    • #11
                      Originally posted by Wes1

                      These instant board companies don't get their work done in China, do they?
                      Some do. Eastern Europe is another popular source. The one I use has a Texas address, but when the boards arrived 10 days later, I was surprised to see that it was in a Chinese candy box (!) with a DHL shipping label that listed country of origin as China.
                      Excellent quality boards: my first order was 5 pieces of a 2x3" board double sided, with PTH and mask both sides. Cost was $80 including shipping!

                      I have since ordered a few more prototype runs from them and one order of 100 pcs of the same board for about $2.50 each. Again, that included shipping. I don't care about country of origin as long as the quality is there: outsourcing works for the "big guys", I don't see why it shouldn't make money for me too.

                      There is a service called batch PCB run from the Sparkfun.com site. It is very cheap: basically they take orders from a bunch of people and batch them together into one order to get economy of scale, then separate them at the end. I haven't used them but I hear the quality is good and the price is very low, but you may have to wait 3-4 weeks to get a board back.

                      Comment


                      • #12
                        For design layouts I like to use Eagle they have a free version for non commercial work >>> http://www.cadsoftusa.com/

                        These guys use to be the cheapest for getting a board made
                        http://www.olimex.com/pcb/index.html
                        Only problem is it takes 10 days to ship to the USA. I think they are in Bulgaria.

                        Comment


                        • #13
                          sparkfun electronics also has a pcb option, you don't have to fill a full plate either.

                          it is chinese manufacture though

                          Comment


                          • #14
                            I have also used expresspcb, but I am presently trying out Advanced Circuits

                            https://www.barebonespcb.com/!BB1.asp

                            They seem to have better service for about the same price and their free software is worlds more capable than the program expresspcb provides. I am doing a small board that will fit two each on the 2.5" x 3.8" size that both companies will make for a very reasonable price. I'm going through the learning process with the software now.

                            I also have made PCBs myself and the process is definitely doable at home or in a small shop. You must make an exact, full size positive or negative of the circuit and that is contact printed onto the sensitized copper clad board. A simple solvent style developer is used to disolve away the mask where the copper is to be removed and then it is placed in an etchant bath for 10 - 30 minutes. Steel wool can be used to remove the mask and the copper is ready for soldering. You can even purchase a tin plating solution that takes just a couple of minutes to plate the copper. But, yes you do have to drill all those holes and that can be a real PITA. Much easier to get them done. And probably just as cheap.
                            Paul A.
                            SE Texas

                            Make it fit.
                            You can't win and there IS a penalty for trying!

                            Comment


                            • #15
                              Hmm. My latest circuit boards don't even have copper on them, just holes. With only about a dozen parts, I'm just pushing the leads through then bending them over in the direction they need to go. There was only one place where the part leads weren't long enough to form the 'trace', and a piece of solid telephone wire took care of that.

                              I most often draw out the circuit pathways with a permanent marker, then etch. Sometimes I drill first, sometimes not. I don't mind doing multiples this way if the circuit is very simple, but for more complex circuits, it drives me crazy just to draw one pattern. I once drew a 6x8 circuit board this way, and with dozens of ic's it was taxing to make sure I got it right before etching. If I'm doing multiples of simple boards, I'll drill first, then just 'connect the dots' with the permanent marker to define the pattern of traces.

                              Who needs a board house when you can use up hour upon hour of your own valuable time doing it yourself at home

                              Here's some useless info- I have in my attic six etching tanks, each about 14 inches long, an inch and a half wide at the bottom and four inches wide at the top. The etchant is circulated by a small propellor on a fiberglass shaft, which runs in glass bearings. VCR loading motors run these props, which turn inside an external tube connected to the tank top and bottom. The ill-fated project died before I could put them to use.
                              Last edited by darryl; 05-27-2008, 04:27 AM.
                              I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                              Comment

                              Working...
                              X