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Re: Good PCB Prototype shops?



Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi Dave,

I usually have PCB4.com do my pcb boards for me. They are known as Advanced Circuits. Their price beats the cost of most proto board houses and their production boards have been quoted a few dollars cheaper than other houses I've used in the past (when dealing with 500 to 1000 board runs, this dollar savings becomes significant). They have what they term a DFM check on your board. Basically, they ensure their CAM department machines will not run into any minimal spacing widths between traces or pads and ensure drill files match common sense. They called today at work about a via that wasn't correct. Found an engineer in Oklahoma used old 4D software and a conversion program to define the pads. Well, strings were used to define the pad placement. Out of nearly 500 vias, 1 was forgotten. Advance Circuits caught the problem and asked the question. They also put the via in at no charge (of course, likely because I do a lot of business with them). But they caught it! That's cool! I'll never get the engineer in OK to update his software, but at least I've used his software before so I can correct his work if necessary in the future (a big discussion I had this week at work).

I'm not sure if they have a free software however. I use Circuit Maker 2000 for my boards, and it runs all the checks I need for DFM success and exports all the Gerber and Drill files within a click or two (board houses have never had a problem with any of my files and their boards are "as designed"). There are some free software's out there which are pretty good. Eagle is one of them, although I haven't the need to use it. Everyone has preferences, but regardless, whichever software you decide to use, you eventually become an expert with the software. What you find is difficult to do, becomes easy as you learn quick work-arounds to do what you need to. All software's have their quirks, this includes Microsim, Electronic Workbench, Modern Orcad, etc. But any of them will do nicely. From a schematic standpoint, Electronic Workbench and Orcad are my favorites. The schematic portion of Circuit Maker 2000 is pre-Microsim era. It takes a little more work, but it can be made to do just fine. The transfer from circuit to pcb is excellent however. Traxmaker (Circuit Maker 2000's pcb layout program) is excellent and easy to make new parts (but don't trust parts in the library unless you've made them yourself). Simple example is a very familiar 1N4001 Diode hole size will be too small for the actual diode. Always check hole sizes to the actual part, no matter what program you use. Don't assume the program knows the dimensions. This will save you much drilling and double side soldering.

What is really nice is when your finished with your design, can you simply export the misc. files and have a board house understand them. What I like about pcb4.com is you can upload your zip file of everything and they will run the DFM check within 1/2 an hour. If there are any problems, you'll get a jpeg showing the problem and its' location. You can then easily correct whatever the problem is and upload a new zip file (. When the DFM comes up trouble-free, you know your ready to let the CAM department produce the board (and their pricing is better than most). Also, you learn how to set the electrical rule checks and spacing checks to ensure every board is trouble free the first time through doing your own spacing checks in whatever software you use.

Not sure if any of this helps, but I've found Advance Circuits to be quite more than a simple proto board house. They do high volume production runs and their product is top of the line, including trace thickness (2oz, 3oz, etc...).

They are putting board houses out of business, literally (boards are becoming a more competitive market. Thus, if we know this, we can use this to our advantage to get good deals on board pricing. They are hoping you don't know any of this however!). Your quoted price may be a magnitude beyond what is possible. Of course, in my case, we do 100's of boards at a time, so we get the good deals. And now they "know" us as a major buyer. Proto boards can be expensive. Keep the board as small as possible for the lowest price. Don't assume autoroughting is the best possibility. I've found auto routing with a small trace width is the place to "start". Then, route each net yourself and calculate what you need (I use ANSI standards for current vs tracewidth/ounce).

Take care,
Bart

Tesla list wrote:

Original poster: David Speck <Dave@xxxxxxxxxxxxxxxx>

List,

I need to have 5 copies of a roughly 4" x 6" PCB with plated through holes made. Any suggestions on good houses to do this for me, especially one with a free PCB layout program? I haven't seen any posts on this topic in at least half a year.
Thanks
Dave