Printed Circuit Board

Fabrication Houses

PCB fabricators usually accept Gerber files, which any good PCB cad tool will export. Some also will accept your actual source files (e.g. Eagle .brd file), but that's risky if you ask me, you can never know if they will generate the artwork correctly if you just give them your sources. Better to generate the gerbers yourself and check them in a gerber viewer before you send them away.

Usually you would export the layers for a 2-layer board as separate gerber files...

Board Outline
Silk Top
Silk Bottom
Mask Top
Mask Bottom
Copper Top
Copper Bottom

and then a drill file for the holes, and slots if any. Some fabs might allow two drill files, one for unplated and one for plated holes.

What the files are called depends on the fab, usually it's just different file extensions, the following are loosely standardised

.GTO and .GBO for top and bottom silk
.GTS and .GBS for top and bottom mask
.GTL and .GBL for top and bottom copper
.GML/GKO/GBR/GM1 for the board outline itself
.TXT for the N/C Drill file of the holes

"PCB manufacturers", "prototype boards", "board house", ...

http://PCBShopper.com Lets you search for the cheapest (or fastest) PCB manufacturer. PCBShopper lets you enter your board's specs - size, layers, preferred solder mask color, and quantity - and shows you a list of PCB manufacturers along with prices and delivery times. You can then sort the results to find the cheapest or fastest manufacturers. PCBShopper currently lists 13 manufacturers, and more are being added. PCBShopper is free to use and is not affiliated with any manufacturers.
Custom Circuit Boards - A PCB Manufacturing company, located in Phoenix, Arizona, that specializes in Quick turn multilayer PCB. With same day delivery (orders before 9am), Custom Circuit Boards is fast, secure, and affordable solution for both companies and hobbyist. Use their online PCB quote form for your next PCB project.
http://olimex.com/ "Olimex is one of the cheapest and fastest services around" -- recc. Byron A Jeff 2002-12-07 on PicList (in Bulgaria so plan on a week or two shipping) Do note that there are significant restrictions on the drill sizes and trace width/spacing you can use for the proto service.
http://www.pcbcart.com/cart.php PCBCart - China, very cheap, good quality and tolerances, automated quote. Pretty much the cheapest around
http://www.spiritcircuits.com/home Spirit Circuits - not the cheapest, but excellent quality/service. Also, they do a very cool *FREE* 2 layer "Go Naked" prototype service, which is worth knowing about. Very innovative/ modern kind of place, seem to make an effort to impress. You may want to check out their "PCB Snap" for a 4-layer prototype
http://www.protoexpress.com
http://goldphoenixpcb.biz/ They are (or at least were) the service behind Sparkfun's Batch PCB service
http://www.pcb4u.com better known as Accutrace)
Saturn Electronics Corporation http://SaturnElectronics.com/ (thanks for the link, M. Miles)
Excel Electrocircuit http://ExcelElectro.com/ (thanks for the link, M. Miles) http://pcbexpress.com/ $100 for 4 identical PCBs (up to 3.375 x 2.875 inches) (that's $25 each) ... has on-line price estimates.
http://www.apcircuits.com . least expensive for small quantities, very fast and high-quality service. Just for comparison, qty. 2 of a 6 inch by 4 inch board ran $90,and that was about 50% setup fee.
Advanced Circuits http://4pcb.com/ makes quick-turn PWB prototypes. There's an on-line form where you tell it how big your board is and a few other details. It immediately gives you a complete price schedule (how much for 2 boards, how much for 10 boards, how much for 100 boards ... how much extra to pay for must-have-it-2-days-from-now.). I find on-line price estimates very useful for deciding whether to make 2 boards and buy a connector between them, or to make one big board. -- David A Cary
Millennium Dataware S.r.l. http://www.mdsrl.it/ "Ultra Fast PCB Prototyping with the special warranty: 24 hours or the PCB are FREE!" -- Francesco Fontana < francesco (at) mdsrl.it >. Millennium Dataware has an online price estimate, and also a PCB discussion forum: http://plcforum.it/
http://www.expresspcb.com Free ExpressPCB Windows layout software. Our express PC board manufacturing service delivers double-sided plated-through boards in 3 business days or less. Often orders for two boards cost under $100.
http://www.pcb-quote.com/ Submits your board to several FAB houses for quotes. Assembly is not addressed.
DynaArt Designs, 3535 Stillmeadow Lane, Lancaster, CA 93536
Voice: (805) 943-4746, FAX: (805) 943-3776
E-Mail: dynaart@netport.com
Web Site http://www.dynaart.com
Home of the "Toner Transfer System"
Coffman Enterprises, http://www.cdh.net/scoff
Email: scoff @cdh.net. PerfectBoard purple paper process to make printed circuit boards.
Electrolube : Photo Resist, developer, Lacquer , Nickel spray, Etchant Electrolube Limited,Blakes Road,Wargrave,Berkshire,RG10 8AW U.K.
Tel. +44 1734 404031 Fax + 44 1734 403084
Isel: Etchant ,plating solution etching equipment etc.
Isel Automation, 6419 Eiterfeld 1,Germany
Sifco : Plating Pen, 5708 Schaaf Rd. Cleveland OH 44131 USA
Tel +1 216 524 0099 Fax +1 216 524 6331
Vero Electronics can be contacted in the US on 1-800-242-2863.
Circuit Works Conductive Pen is available from Ocean State Electronics, (800) 866-6626.
The catalog number is CW2200
NEPCON holds trade shows that focus on electronic manufacturing equipment and tools. The next show is in Texas during the last week of October. This will give you a chance to kick the tires and test drive some of the equipment.
Manncorp makes a pretty broad line of equipment. Everything from manual pick and place machines up to some fairly pricey automated lines. The sales people are pretty sharp and are willing to answer dumb questions.
http://www.bomir.com/ This equipment is imported from Poland. Screen printer, manual pick and place with paste dispenser, and a batch reflow oven for US$ 12k.
http://www.apsgold.com/ Through-hole lead forming machines and SMT equipment.
For automated equipment, Upgrade Technologies is the leading contender at the moment. They started out with a focus on ovens. Screen printers and pick and place machines are fairly recent additions to their product line.
PCB Fab Express http://pcbfabexpress.com/ has on-line price estimates. PCB FAQ:
http://cal003109.student.utwente.nl/stefan/el in the PCB section. (broken link as of 2005-07-18)
Imagineering, Inc. http://pcbnet.com/ intro offer: $25 each for 2 Layers, $50 each for 4 Layers (quantity 1) max. 60 sqin., max. 14in length.

PICList threads: "cheap pcb fabrication needed"

FAB houses in the UK.

http://www.lyncolec.co.uk/

Other web sites with long lists of PWB fabricators:

http://www.everythingpcb.com/p13057.htm long list of Printed Circuit Board Manufacturers -- think we can get that site to link back to massmind ?
http://dmoz.org/Business/Industries/Electronics_and_Electrical/Contract_Manufacturers/Printed_Circuit_Boards/ Many PWB fabricators and assemblers are listed at dmoz.
Portland Robotics used to have a list of board houses http://portlandrobotics.org/index.php?id=21#132 , but today (2005-07-18) I only see one board fab listed.