Professional PCBs Almost Cheaper Than Making Them at Home

165,821

163

55

Introduction: Professional PCBs Almost Cheaper Than Making Them at Home

While there is great satisfaction in home building PCBs, adding up the cost of the blank PCB, etchant and the drill bits comes to over $4 per board. But for $6.25 a board the whole thing can be made professionally. This Instructable takes you through the steps to create the Gerber files that the PCB manufacturers need. The total cost was $75US including shipping for 12 boards. 3 boards would be about US$62.

This Instructable builds on some great work at https://www.instructables.com/id/EXU9BO166NEQHO8XFU (Draw Electronic Schematics with CadSoft EAGLE) and https://www.instructables.com/id/EZ3WN1QUKYES9J5X48 (Turn your Eagle schematic into a PCB). Eagle is free.

Step 1: Designing the Schematic

The full schematic is at http://drvernacula.topcities.com/315_mhz_solar_powered_radio_rptr.htm and is the schematic for a solar powered radio repeater module.

Step 2: Place All the Components

The instructable links on the intro page show how to create a pcb from a schematic using EaglePCB. One main difference is that none of the design rules about track widths need to be changed at all (the drc design rule check). The defaults are all fine and while the tracks look really thin and close to pads it doesn't matter as the green solder mask makes it very easy to solder. In fact, these sorts of boards are much easier than soldering up prototypes. Some big pads were used for connecting external wires and there were a few extra comments added for the white component overlay layer.

The wonderful thing about having boards like this made compared with building homemade boards is you don't have to worry about trying to optimise the autorouter for a single layer. Just run the autorouter once and it defaults to double layer mode and it always produces a 100% design automatically within a few seconds. Even with components a lot denser than this board Eagle always autoroutes the whole board.

Step 3: Fix Any Errors

Sometimes one finds a better component in the library or changes a component. To rip up and replace the tracks click on the ripup symbol (green circle), click on the traffic light (red circle) and then reroute (yellow circle).

Over the last few years I've found a few tips and tricks to making better boards:
1) To get tracks closer - Tools/Auto/General and set the grid to something like 10mil
2) To make data tracks thin but power tracks fatter, Edit/Net (at the bottom) and start typing in a text box to name the class. I use three classes; Gnd, Power and one for all the rest.
3) In DRC, distance/copper dimension change from 40 to 20 - this allows two tracks to fit between IC pads, which can greatly increase board density.
4) In DRC - clearance/pad to via increase from 8 to 40. (leave all the rest at 8mil). This increases the distance between vias and pads so less chance of bridges when soldering. Surprisingly, this also sped up the autorouter too.

Step 4: Create a Drill File

The manufacturer needs to know what drills to use. Eagle has automatically used whatever drill fits the components that have been chosen. Go to File/Run and select the file "drillcfg.ulp". I selected inches rather than mm and that seemed fine with the manufacturer. Click ok then ok again. It will save a file with a .drl extension.

Step 5: Create an Excellon Drill Data File

Click File/Cam Processor

Step 6: Open the Cam Processor

In the Cam Processor click File/Open/Job

Step 7: Select the Excellon File

Select Excellon

Step 8: Click on Process Job

Click on Process Job. This will create some files. Close down this menu with the x at the top right.

Step 9: Create the Gerber Files

Repeat steps 5) and 6) to reopen the CAM processor and this time open the file gerb274x

Step 10: Create the Gerber Files

This is the important bit. You need to click on each one of the tabs circled in green and ensure that Mirror (circled in yellow) is off. As you click through the tabs you will notice the Nr and Layer lines highlighted on the right will change. One default you might want to change is component values - in my copy this was deselected and the silk screen ended up with U20 but not the actual chip - eg an IC might be 74HC04. Click along the tabs to Silk Screen Cmp, and click on 27 tvalues. Once all the mirror boxes are definitely unchecked, click on Process Job (red circle).

Step 11: Collect All the Files and Zip Them Up

I collected 10 files, put them in a temp directory and used winzip to create a single zip file. I have a feeling that one or two of these are not actually needed by the manufacturer but I sent them anyway. The file the manufacturer definitely does not need is the .sch schematic file.

Steps 4-11 are summarised in text format at http://drvernacula.topcities.com/creating_gerber_files_from_eagle.htm

Step 12: View Some of the Files Just to Make Sure

Download a free Gerber file viewer

Step 13: View a Gerber File

The drill files can be viewed with a text editor.

The Gerber files can be viewed with a free Gerber file viewer. I went to the website above and installed Viewmate. It appears in the Start menu of windows as Start/Programs/Pentalogic. In Viewmate I clicked on File\Open and browsed to C:\Program Files\EAGLE-4.16r2\projects\RadioRepeater and at the bottom of the windows changed Files of Type to *.*. As an example this is the .sol solder side file

Step 14: Find a PCB Manufacturer

This company OurPCB is in China and stood out from some of the others in that they freely advertised their price for small quantities. Shipping is FedEx and to the US they quote $22. The $40 above for a 10 sq inch board is for all the 3 boards, not per individual board. At a quantity of 100 the price per board is $1.80 each. They can give a firm quote once they get the zipped files.

These boards arrived in 9 working days. There were a few problems initially with me sending the wrong files (which is mainly why I wrote this Instructable!) and they were very patient and polite from their end. There were also some email problems in that emails coming back were totally blank. I was able to read the source text and at least work out who they were from but I nearly did delete the mail as junk mail. Finally I ended up communicating by Skype text. They all write very good English which is a bit embarrassing as my Mandarin is non existent. My kids are learning Mandarin at school though.

Payment was via Paypal which remains safer than using a credit card (for both parties) and far cheaper than an interbank transfer.

I hope this Instructable is useful. I have built many hundreds of prototype boards over the last twenty years but I think from now on I will be getting boards made professionally.

Be the First to Share

    Recommendations

    • Toys & Games Contest

      Toys & Games Contest
    • Big vs Small Challenge

      Big vs Small Challenge
    • Fix It Challenge

      Fix It Challenge

    55 Comments

    0
    rushpcb.mkg
    rushpcb.mkg

    3 years ago

    Great guidelines. This will help PCB professionals to manufacturing. Very useful walk through.

    0
    FeatherG
    FeatherG

    5 years ago

    I'd like to recommend a free, zero-install, Web-based EDA tool called EasyEDA which integrates powerful schematic capture, mixed-mode circuit simulation, PCB layout and PCB order service. With it, the process of making PCBs will become much easier and also can save your time and money. Details can be seen by https://easyeda.com/Doc/Tutorial/PCBOrder.htm#PCB-Order

    0
    jfrankhauser
    jfrankhauser

    Reply 5 years ago

    Also, With EasyEDA, once your done designing the PCB, you click the Fabrication Output button. If you look at the top left corner of the order form, you can download the gerber files free.

    0
    jeanzhu
    jeanzhu

    5 years ago on Introduction

    You guys are
    really professional. When I started doing an international project, and I
    contacted Robert of SysPCB in China, always was very attentive and willing to
    give me the necessary help to avoid mistakes, today more than ever I appreciate
    all the time devoted to the project of PCBs and everything I learned from.

    0
    SreekarG
    SreekarG

    6 years ago on Step 11

    thankyou for the wonderful walkthrough. This is really helpful because communicating with the manufactures about design requirements is really difficult without gerber files.

    0
    PrashantV1
    PrashantV1

    6 years ago on Introduction

    We are professional PCB Manufacturer in India. We specially work for small batch qty. shipped the PCB all over world.

    you can visit www.photozonegraphics.com for more details

    0
    echoalex
    echoalex

    7 years ago on Introduction

    Hey, this is one instructable that I have been using as a reference material for the last 3 year, when ever I want to make a gerber file. I keep forgetting what to do while making a gerber file. I think its about time that I thank you. Thanks a bunch for this amazing instructable.

    0
    dosadi
    dosadi

    11 years ago on Introduction

    I'm surprised no one has mentioned SparkFun's batchpcb.com prototype service. They take small orders and combine them into panel orders that are processed by Gold Phoenix. 2 layer boards cost $2.50 per square inch with a $10 setup fee. They're slow, though. Expect to take at least 3 weeks while they gather together a batch order and transit from China, etc. Since they use Golden Phoenix to produce the boards, you already know GP will accept your files when you're ready for a larger batch.

    0
    SiliconFarmer
    SiliconFarmer

    Reply 10 years ago on Introduction

    The Portland Dorkbot group has been doing batch PCB orders every month for over 8 months, and recently opened it up to anyone. Basically, the cost is $5 a square inch and you get three copies of your board. 6mil traces and spaces, double sided, with solder mask and silk screen. I submit a board or two almost every month. This is perfect for Eagle CAD sized boards. Check it out at http://dorkbotpdx.org/wiki/pcb_order

    0
    killersquirel11
    killersquirel11

    Reply 8 years ago on Introduction

    And this guy accepts straight eagle files, so you don't even have to deal with gerbers at all. I had one run to get eighteen total boards that cost under $50. Granted twelve of those boards were really tiny (.7" diameter). I highly recommend this.

    0
    abraxas2
    abraxas2

    11 years ago on Step 10

    Thanks for taking me a leap forward. When I process this board into files via the CAM, I notice the check box "Fill Pads" is checked and I can't uncheck it because it's grayed out. Sure enough the artwork in the files generated has all of the pads filled in. I'm doing home brew boards so I need these holes as a guide for my drill. Your help in unfilling these holes is appreciated.

    0
    siddhc
    siddhc

    Reply 9 years ago on Introduction

    Hi,

    I also have the same problem .. "Fill pads" is checked and I cannot un-check it.

    Please help if you figured out the solution.

    Thank you very much,

    0
    DaleS44
    DaleS44

    9 years ago on Introduction

    My misteak! Roller microchips should read roller micro switches! The kind that are actuated by a cam. Is shaping the pc board and cutting slots for some of the components done by another device like a router (not trace router) that requires a separate instruction set?

    0
    DaleS44
    DaleS44

    9 years ago on Introduction

    I recently needed to build a simple PC board so I downloaded Eagle PCB. With the help of a couple of tutorials and your instructibles I was able to complete the project to the finished, and previewable, gerber files. Your step by step instructions made the process very seamless.
    I have one question though. My PC board must have a u shaped cutout in the top of an otherwise rectangular board. I also need to mount some roller microchips on this side where there is an angle and very specific measurements between holes.
    Is there a feature in Eagle PCB that allows more specific adjustments to the size of the board beyond pulling in on the side frames and is there a way to locate non-pad holes for mounting the micro switches so that they are in a very precise location and can be drilled when the boards are being manufactured? I do have the entire project in AutoCAD and I have a drill layout and shape as one of the layers. I am just unable to figure out how to export this layer in a format that can be combined with the output files from Eagle PCB.
    Thank you for your help and for taking time to respond.
    Dale

    0
    Dr_Acula
    Dr_Acula

    Reply 9 years ago on Introduction

    Thankyou for the kind words.

    I am not sure about changing the board shape but I think there are other instructables that might show how to do this. Search for Eagle? Also you would probably need to ok this with a PCB fab house. Maybe start with the PCB manufacturer first.

    Re non pad holes, I have found it easiest to design a new part. There are instructables on how to do this. One of the things you can add to a new part is a hole (of various sizes). It helps to have the exact part dimensions.

    Sorry I can't help further but there are other instructables written by authors who know a lot more about Eagle than me!

    Cheers, James Moxham

    0
    cardinalflyer
    cardinalflyer

    9 years ago on Step 2

    This comment may be late in the game:

    "always autoroutes the whole board"
    Not true.
    I have been creating Arduino-size PCBs (80x100mm, 60x80mm) with 3-4 extra SMD ICs, and Eagle has hard time completing it. One needs to take care with component placement or you find yourself having to clean up a lot.
    Oddly, even with 2 ground planes, the place where I have been left hanging is ground connections! I've been having luck with that by moving signals around manually to let the lower & upper ground areas overlap and then adding a via to connect them.
    I'm using the free eagle software, and have the 1-sheet schematic pretty full up, not a lot of interconnections shown to free up space, bunch of parts with just signal names hanging off.

    0
    hamraddude
    hamraddude

    12 years ago on Introduction

    OurPCB sucks thundershit. I asked them for a quote on a 2.5 in x 4 in double sided PCB, and the price came up to 6.30 USD + 30 USD (!) shipping and 100 USD "tooling charge". Yep, 136.30 USD for a 2.5 in x 4 in double sided PCB. No thanks, I'll keep making my own.

    0
    votecoffee
    votecoffee

    Reply 10 years ago on Introduction

    For smaller scale you need a different PCB company. Different companies specialize in different things:
    http://www.seeedstudio.com/depot/fusion-pcb-2-layer-10cm10cm-max-10pcs-p-396.html?cPath=64_12
    http://iteadstudio.com/store/index.php?main_page=index&cPath=19_20

    A quick price checker for these and the rest:
    http://www.ladyada.net/library/pcb/costcalc.html

    This one has a really good student offer, $33 for 3 boards with all bells and whistles I think
    http://www.4pcb.com/

    And of course they already mentioned sparkfun and some other sites that do single boards at a higher price.

    0
    Dr_Acula
    Dr_Acula

    Reply 12 years ago on Introduction

    Just double check that $100 - they tried to charge me that last month but it was because it was the Chinese New Year and I think they wanted a holiday. $50 is the usual charge. I think if you want just one board do it with a prototype. If you want 3, there may well be other manufacturers where the price is cheaper because you can piggyback on other people's orders. But if you want 10 boards or more, it ends up very good value IMHO. Tonight I'm sending off an order for 10 sprinkler controller boards and it works out good value, especially if I cost in my hourly rate building 10 prototypes with point to point wiring vs 1.5 hours designing a PCB. Maybe try searching for some of those other manufacturers that piggyback single orders.