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Welcome to my Milled PCB (Printed Circuit Board) Prototype page, it is evolving so please be patient. If you are looking for a service company to manufacture your PCB Prototype than I would recommend you contact my good friends at Circuits West www.circuitswest.com located at 410 S Sunset St, Suite D, Longmont, CO 80501 CustomerService@CircuitsWest.com phone: Toll Free 1-877-650-5321 Phone 303-772-9261 Fax 303-772-0490. They will take care of you, just tell them that Ben from www.ProcyonPCB.com sent you. If you were looking for Procyon PCB, Inc., it is no longer operating as a PCB Supplier for general purchases. Please send any questions about this site to FLHTK(at)procyonpcb.com make sure you place a @ in place of the (at) This site is NOT for the beginner first learning how to use their machine or build a milled PCB prototype. I will say now that I will assume you are here because you want to improve and build upon your basic knowledge of milled PCB's. If you want to learn about milling PCB boards and how to properly make them so that your boards can look as nice as those that you see at electronics trade shows or on You Tube than you have come to the right place. This web page is just starting out, so please check back often because I will be adding a lot of interesting pictures and samples of how to make your milled boards like a professional. If you need to ask a question, please email me. I'll get back to you as soon as possible. If your company would like to consult with me, I'm sure that can be arranged as well. See I used to own and operate a milled PCB Prototype service shop called....you guessed it Procyon PCB, Inc. I decided that on 12/31/2011 to no longer operate the business. After seven years of operating the business and working a full time job, I decided to throw in the towel while I was still at the top of my game and close up on my choosing. This was a niche business that catered to specific clients who needed very small quantities of boards to test before continuing into a full production, or they needed just a few boards to make something work. I learned so much from how to take an idea, build a business plan, obtain financing, purchase capital equipment with initial tooling and materials, and start operating as a real business. I learned the true meaning of LEAN SIX SIGMA and how the real business world works. There was no way I could compete with the real board houses located across the USA (they have been slowly disappearing). But having that niche, that ability to operate freely as an independent operator was a great experience and I recommend anyone who has the initiative to take that dream and follow it through. So I now have all this equipment available for my personal use or to sell (if anyone is interested in purchasing any or all of my shop stuff, make me an offer, you never know I may just say YES!) or if you are looking for a contract employee (1099) with LPKF equipment for making PCB prototypes, contact me via e-mail at FLHTK(at)procyonpcb.com make sure you place a @ in place of the (at). Many university students had their first designs cut on my LPKF Protomat H100 machine. It was a learning experience for them as they learned how to properly make an extended Gerber file or DXF, correct mistakes that I would find in their design, and in general become real design/layout engineers. I loved the idea that I helped mould these young minds into something other than skulls full of mush! My favorite example was a 16 year old high school student from Reisterstown, MD who was in a Robotics Club at school and he needed a control board made. This youngster was amazing. He took an existing design and layout and decided he needed to make some improvements. So with my guidance on-line and his skills that he was rapidly learning, he did what a lot of college graduate engineers can't do. He designed his first electronics board using all through hole technology but he did it and I made his board Pro-Bono. His robot went on to win some award locally, but I am proud of the young mans initiative to think outside the box. So lets get on with the Milled PCB's....... Before we even discuss milling a board, I recommend the following tools........... Check out www.rfcafe.com everything you need to know about RF electronics; and Kirt who runs RF Cafe is a great man. Check them out! Check out DesignSpark PCB freeware. DesignSpark is a simplified version of Easy-PC which is a scaled down version of Pulsonix PCB software. If you have access to Pulsonix you have it made. Easy-PC is the next best thing. But you hobbyist who want it all for free and you haven't checked out DesignSpark do so. it will be your best friend. I don't want to get into a pissing contest over which layout/design software is better, but it's my web page and I have used all three packages. Every program has its strengths and weaknesses, but I haven't found much weakness with the Easy-PC. In the PCB business I ran into a huge problem that I never realized when I started the business. That there are several hundred varieties of PCB design/layout software versions being used. I never knew what I was getting when I opened a zip file from a potential client. I've had everything from AutoCad v1 (it works for them so why upgrade!) to the latest and greatest Mentor Graphics product. I remembered talking with LPKF Tech Support about how to read some files I was sent, our discussion about messy Gerber files (Gerber Files meaning any file we were sent regardless of the format) was pushed into a conversation about how difficult it is for any board house (let alone the Tech Support) to try to decipher what has been sent to them. We discussed why some board houses basically want you to download their software and then use their software to create the board files. I have literally spent hours fighting to read some files (of which I never got paid for). I did a lot of research on finding a decent program that would allow me to import files and read them so I can at least see what I am supposed to be looking at and Easy-PC was my answer with their add on option package for Gerber File Import . Most in-house prototyping use just one type of PCB layout program so most users wouldn't have to worry about all of these other programs out in the real engineering world.
At the top of the page I have left the four main areas for my original web site because all of the data is already located on those pages. Now this discussion page is mostly going to reflect using my equipment which I purchased from LPKF. Bet you don't know what LPKF stands for? ...................Leiterplatten Kopier Fräsen translated from the "FATHERLAND" "circuit board copy milling". When I was first told this many years ago, I thought "what a funny name" but it really made sense when you see what can be accomplished with these proficient machines (as well as MITS, TTECH and others) when used as intended. Now I know that there are many people still out there that LOATHE milled boards regardless of what equipment it is made on. They had such horrendous experiences years ago or even yesterday. Mention this technology and they run away screaming. I am here to tell you that milled PCB's are a viable resource that can give you that edge over your competitor and the key to being successful at milled PCB's is having single ended users solely responsible for the usage and maintenance of the machines. I have been invited into laboratories where there is a pcb milling machine (name your favorite brand) located under a very expensive sound cabinet, buried under a pile of paper rubble. When I ask about the machine, I get the reply "oh, that was a mistake in ordering" , "it has never worked right from the day we got it", or "no one can figure it out so it just sits there", and my favorite "oh, Joe ordered that five years ago and he doesn't have time to PLAY with it anymore"..... I just cringe at those answers. No matter how much your company paid for a PCB Milling Machine, it wasn't meant to sit and collect dust, it was meant to operate creating PCB's. You may not view the purchase of that equipment as wasted personal money. But as a former business owner, I know from real life experience that we are talking about MY money, and I don't know any business owner who purposely allows his employees to waste his or her precious dollars. A properly run milled PCB prototype lab setup should make available to the company the ability to start a project and build upon the basic design so that instead of wasting time waiting for a board to be manufactured and shipped back to your lab. Your in-house PCB prototype lab should be able to make most double sided boards in a single day and the engineers should be testing it later that afternoon. Very little time lost. So little time that in fact a engineer working into the evening can make any additions or corrections for a second iteration and have a new board made the following day and tested. Repeat this cycle and you have probably saved at least a weeks time or more. Time is money. Now multiply this over and over, and you can easily see that a properly run in-house lab can actually shorten your delivery time for your final product. I personally know a situation where there was a total of about 50 iterations made of a set of boards for a project. Having the boards made in-house where the boards were made starting at 5AM in the morning the engineers had their finished products by lunchtime and tested before they went home in the evening. Before leaving they would make their design corrections and emailed the new files to the "board techs". Next morning the early arriving techs would start the board and have it completed by lunchtime again. Having this done everyday allowed delivery of the final product at least six months ahead of schedule. Think how much that saves. Now some requirements may take longer to make or can not be done at all in-house and have to be sent to an outside vendor, but the savings can be tremendous and the reward great for getting a product into production ahead of schedule. But don't expect this to happen as soon as you uncrate a PCB milling machine. The ramp up time to get all of the nuances figured out can take months or even longer. I remember my first learning experience with a LPKF 95s II machine. No matter what I did, I couldn't make a working board if I tried. It finally clicked one day when another user of the same model machine was asked to sit with me and see what I was doing right or wrong, and I was doing everything right, I just didn't follow through with all of the prep work in CircuitCam prior to exporting the job to the machine using BoardMaster. Once I got it all straight, off I went. I must have made the same test board at least 20 times just to verify what I was doing as well as trying different techniques using the CircuitCam software. Once I became familiar with a good portion of the CircuitCam software I was able to build multilayer boards. I got so adventurous and a bit cocky I asked one of the engineers I worked with to design a eight layer test board for me to try. Well I was one of the first people in the USA to actually make a successfully manufactured eight layer board using the standard LPKF multilayer board process. Shortly I became very knowledgeable in Milled PCB's only because all I did 5 days a week was make milled PCB's. ***The number One Rule in Milled PCB's is a competent core group dedicated to the use of the equipment as well as its maintenance. This can be a single person or several people, as long as they all know what they are doing and keep good recorded logs of the usage. Spindles go bad, motor brushes wear out, software updates as well as spare parts need to be kept available. ***The Second Rule in Milled PCB's is to use FRESH TOOLING for each and every job. Replace tools before their end of life with FRESH NEW TOOLS. Do not keep reusing a tool because you think it will save you money, on the contrary it will cost you more. Yea, tooling can get expensive real fast, but this is where those who had bad experiences with milled PCB's come into play. Let me explain, one time I was called by another LPKF user and he wanted to know at what step in the process should he take a putty knife and scrape down the burrs on the board. I am not kidding you.........this guy was serious. Now burrs occur, and yes I always have emery cloth of different grit available, but a putty knife? These must be some serious burrs. I've cut 10 ounce copper (you read it right TEN ounce Copper thickness) and didn't have much of a burring issues. Back to this burr and knife thing....so I went for a visit and saw that they indeed were using a putty knife to remove the burrs. I asked a real simple question, and may be I was out of line for asking such a stupid question, but "how come you just don't change the tool with a new one and that will get rid of your burr completely so you won't have to use the putty knife?" You wouldn't believe the answer..............I was actually told "we're not allowed to change the tool, it cost too much." A burr is a sign to change your tools or your feed rates if it's a fresh tool. If you are not allowed to change the tools because it cost too much, you have a much bigger problem going on. ***The Third Rule of Milled PCB's is to do your maintenance of your machines on a regular basis. When I was in the Navy there was a system called 3M (Maintenance, Materials, Management) and a sub system called PMS (Planned Maintenance System) Every machine, every thing on that ship had a PMS Schedule from a Daily, Weekly, Monthly, Quarterly ,Semi or Annual requirement upkeep that had to be done and verified. I wouldn't go overboard on this, but every machine needs some type of attention during the year. Do it! Make it your goal and responsibility to make sure it gets done. Otherwise, your precision machine is going to be a pile of garbage because you didn't take care of it. Simple oiling of metal surfaces, cleaning out the buildup of milling dust. Replacing worn motor brushes. Simple things that only take a few minutes but will save you hours upon hours of potential tribulations.
Above are a few examples of boards I have made on my machine. One is only limited by the operators knowledge of making a PCB board. Below are some of the items I used to offer for my clients. Anyone with any milling pcb machine with plating ability and heat press can offer these items to their design engineers, and in my opinion, if you can't get your people to do these minimum items than you are losing money.
As a side bar, if you look carefully at the paneled background of this web site. You will see a BGA, QFP and assorted SMT layout. If you had seen the original board this picture was taken from you would have been impressed because it was made on a LPKF H100 machine using 3mil line and spacing technology, you can mill down to 2 mil line and spacing with this machine, and if I had the money to invest, I bet you I could successfully do 1 mil line and spacing with the LPKF Protomat H100. In order for your boards to look like they came from a board shop using ordinary manufacturing techniques you must take your time and not rush, use good clean sharp tools, good board support with proper adhesion to a flat surface. Please remember unless specified any board house is going to make your boards according to the standardized IPC Specs. The IPC specs are basically a generalization of requirements that are agreed upon by many different parties so that board shops all across the globe can compete using the same standards. Or as I like to paraphrase "a set of specifications with enough leeway to allow all PCB shops a even footing at the basic levels, sort of like a golf handicap allows players of all skill levels to play together without issues".
So when you have your design finalized and ready to be exported as a Gerber-D or Gerber 274-X, or ODB++ (which I prefer) you are ready to import the files for processing for your CNC (computerized numeral controlled) machine. Once you have processed the board you will want to take a few minutes to verify each layer is aligned to a specific point of reference. A via or drilled hole or even some other item. Just make sure it is a common point on all layers. If you are using a "Rub Out" command make sure all copper is removed that is not needed. The best way to verify this is to set each layer to visually show each tool cut as a solid path. Set your background as "BLACK" and if you see any black you know you have copper showing on the final product. Of course you may want a copper fill for ground purposes, and then again, I have seen well intentioned milled boards made by people who claim it is impossible to have all left over copper removed on a milled board. This is a big and widely held misconception. Any board can be made to have all excess copper removed. One just has to understand the software package they are trying to use to process the data. Make sure all of your layers line up and look correct. I have ruined jobs because I didn't take a minute to verify that all layers are oriented correctly. Please be careful of "MOUSE EARS". Those of you who have experienced these errors know what I am talking about. Especially those of you using older versions of CircuitCam. LPKF has spent a lot of time trying to eliminate the generation of this error. I had a set of Gerber Files that always generate the mouse ears on a specific layer. For a short period of time I did some "Beta Testing" for CircuitCam and this was the very first file I would import into the latest version of software that was being tested. The two versions of v6 CircuitCam I use seem to eliminate the problem, at least I haven't seen this problem (knock on wood) in a long time, like when I was using v5 software. Don't know anything about the newest programs, but hopefully "Mouse Ears" have been eliminated completely. Many a job have been ruined by a surprise in the software. Every once in a while I still pull a check in BoardMaster under "Real Tools" to see if I can catch any Mouse Ears. I recommend you do this even if you think you're safe. Log into the LPKF User Database and read all about this problem in detail. When viewing a job with all layers present, look from the top down through to the bottom layer. Make sure that bottom layer is reversed or it will be milled backwards, and then it's too late. Now multilayer boards can be a bit more interesting. I personally like to view all internal layers as if they were a top layer, only because I visualize internal layers of a multilayer board as a bunch of top layers stacked together. You may not see it this way at first, but over the years I had to learn how to make various types of stacking order of layers to meet the requirements of the designers. So the easiest way for me was to look at all middle layers as top facing layers. Only the bottom layer and associated Silk Screen and Mask layers had to be reversed as well. There is a limit as to what you can accomplish with your machine, but the operator has to try to overcome any obstacle to accomplish the desired need from the board designer. Slots or specific depth cuts can be accomplished and sometimes we have to think outside the box. For instance, I remember talking a user through the process of creating an additional layer so that he could use four additional tools to accomplish a special step to mill down or step mill the board . This person just couldn't understand that if you treat each layer of a board as a separate board that is pieced together and not a single board made up of top, bottom, board outline, via/holes or other layers. The CNC machine doesn't care because it actually treats each layer you import as a separate job whether you realize it or not. You can "Frame" a area of a board that has very small spacing and line widths and use a second set of tools and fight the software to make sure it is correctly done. I have used framing in the past successfully but I can never remember how to properly set it up when I need it because I use it so rarely. I used to keep calling the LPKF Tech Support to talk me through it. So I now go the "Lazy Method" and copy and paste the layer as a new job or layer and just work that small area using the proper tooling as specified. Then go back to the original job and finish using the general sized tools. Because these tools are too big to enter the small zone area the bigger tools just avoid that area and mill all around. Always work from small to large except when you need to do some special milling. It may be beneficial at times to skip the smaller tool and start with the third larger tool and work down. The larger tool is stronger and can cut longer, also you will have an overlap area from one tool to another. Take advantage of the overlap area and reverse the tool usage so that the smaller tool will actually last longer because of less cutting on the outer edges. Don't believe me, just try it and you will become a believer real fast. You will actually get longer tool life by doing this simple change. I know that with the LPKF CircuitCam software there are plenty of what I call hidden wonders. Capabilities in the software that are mentioned in a brief sentence in the manual, but no real disclosure on how to use it in any real application. This is where you have to play with your software or at least call LPKF Tech Support and ask. Stacking, add to stack, remove from stack, commands that allow you to manipulate a circle into an ellipse or to create all kinds of interesting shapes or make changes. Now I have a rule to never make any changes to another persons design unless I have communicated with them that there is a need for me to make a change, but to know how to use the software is a huge benefit as the operator of the lab equipment. MATERIALS I can write for days about milling PCB materials. Over the years I have fought with many a material to make a board. Sometimes I win and sometimes the material wins. Some materials just are not mill friendly. I would quote many jobs for special RF materials and to be honest, if the request was in FR4 material it would cost pennies not thousands of dollars. Every time I had to mill any Rogers Duroid type/style material other than RO4000 series I would actually gamble on whether I was going to make any money on the deal. Duroid materials are not what I call milling friendly at all. They do mill, but the finish is not up to par with how FR4 can look. I have used successfully a machine water based lubricant that I would spray onto the board as I mill the circuit. It makes a mess, but it will make the process much easier and hopefully successful. The heat that is created by the milling tool and the way these special RF materials behave under this heat stress combined cutting action makes for a gummy mess. Changing the tool feed and rotations speeds can help, but it is like finding a needle in a hay stack. The copper also has a tendency to lift off of the substrate. The surface tension and adhesive is severely reduced due to the Teflon compounds that are in a lot of these RF materials. Not much sticks to Teflon (personally I think it's a conspiracy by DuPont but that is my opinion). So the moral of the story here is milling these RF materials can be a challenge to mill but can be done. I would always inform the client that to make their circuit tracks as wide as possible. The wider the traces the CHEAPER the board costs are and the least chance of the traces from lifting up off of the substrate. TMM type materials are great to mill and drill. The problem is cutting them to usable board sizes for your machine. They don't shear well and if you have to buy large sheets of 125 mil material you are in for a lot of fun. This stuff plates great, mills and drills great, contour mills well too. What I love about TMM is that the copper adheres really well and does not lift as easily as the other Teflon materials do. Plating these materials will be discussed under the plating section later on down the page. As for FR4 materials, there are different types available but basically they all mill and behave the same. These materials are what our machines are really made to cut. It would be a perfect world if every PCB board was to be made out of FR4. I have made specific custom thicknesses using my MultiPress from LPKF. If you had to buy any other piece of equipment, get some type of heat press so that you can make specific FR4 materials. All you need is some FR4 prepreg (cheap) some single sided copper FR4 material any thickness and you can make a specific FR4 board to any desired thickness. You can also just buy the copper sheeting and make it all. When you need to have it NOW and not have to wait, or you have to make a minimum purchase of so many sheets at a big cost, making your own is nice. Make what you need in just a few hours. You should be able to mill a 4 mil (0.004") thick FR4 single sided copper clad material on any CNC PCB machine. If not there is something wrong somewhere. So you can get a picture of this, a typical piece of paper is 3 mils thick (0.003"). No laser machine needed here, just a plain ol' milling machine at work. I haven't had a need to mill thinner FR4 single sided copper clad material. But I would be hesitant in trying anything thinner and for my needs the 4 mil material along with a three to six mil thick prepreg would be sufficient to make a decent multilayer board or even a flexible one.
Milling Polyimide Material Polyimide material is great stuff to work with. I have made one of my favorite and most difficult to mill jobs out of this stuff. This stuff is amazing to work with. It mills well, but is isn't cheap to buy. Plating this stuff is not to difficult so I recommend, go ahead mill away and don't be afraid of polyimide copper clad material for your boards.
Milling Ceramics Milling ceramic materials again is not something you would normally do, but can be done. When you drill, watch for sparks when the bits get dull. This is one material you need to use a lubricant on or you will be in trouble. Most of my experiences on ceramic substrates were a reverse layout technique. Meaning milling out where the traces would normally be. The troughs made by the end mills were then filled in with some sort of conducting metal using some sort of post process completed by the client.
PLATING Plating is anther issue people have against milled boards. I would have to agree that the typical copper plating on milled prototype boards SUCK, but this doesn't have to suck, it should be GREAT each and every time you plate a board. They suck because of several problems. CHEMISTRY, and maintenance of both the plating equipment and the chemicals. I have to be honest, it took me years to figure out what I was doing wrong, and why were my boards only getting decent quality plating when I had new fresh chemicals in my plating tank. I used to spend hours on the phone, writing emails to LPKF Tech Support complaining about plating. I am not bashing or complaining about LPKF Tech Support. They have been a great asset to me personally and I owe them many a beer for pulling my fat rear end out of a jam. Using any typical plating contraption (in my case I had purchased a LPKF MiniContac III HF Plating Machine) in my opinion should yield you many years of quality plating if you follow some simple rules religiously. I have been using the same two five gallon containers of my Copper Sulfate solution for seven years because I CLEAN and MAINTAIN my chemicals and platter. I don't do it once a year, I do it all through the year. Sometimes twice a month sometimes I can skip a month or two. Depends on what kind of work I am doing. The key to platting is clean usable chemicals. If you need your bath on a daily basis, I would recommend you modify your setup so that you have both a 1 micron filter and a 5 micron charcoal filter inline using a acid resistant pump to move the solution through the filters and back into the tank. Otherwise you are just wasting money. Cleaning your copper solutions is easy and described in detail somewhere on the Think and Tinker web site under Through hole plating. The site tells you everything you need to do this. Clean your solutions. Clean your platting plates hangers and buss bars in a solution of citric acid and plain water. Keep them CLEAN. Do this several times a year. I actually spray my copper plates down after each use with just plain water to remove the copper sulfate residue from it as well as the black ink deposits on the copper plates. You will need to recharge your copper sulfate solution so make sure you have additive for it. I also recommend to NEVER keep your solution in the tank of your plating tank over night. I empty my tank after each use and clean the tank with fresh water. If you follow this steps, you will have awesome plating for each and every job. You will also want to have plenty of fresh solution pre-made so you can add fresh solution as you lose some each time you empty your tanks and over time you will be a bit low. If there was one improvement I would suggest to LPKF on their plating machines would be to somehow design into their plating systems a double filter system with a electric pump. Parts wise we are only talking about $200 and most of that is the cost of the pump. But look at it this way, LPKF can charge money for the filters..........hint....hint....hint! LPKF has added to their plating options a silver paste that is actually nothing more than silver Via Fill. I love this stuff. Finally something available that was affordable (packaged quantity is greatly appreciated) and no real messy chemicals needed to make your prototype boards. This paste is also great for coating the walls of the vias on Teflon materials. Once you cured it you can then copper plate the board as normal and have a decent copper plating finish. The third option are the old rivets. They work, but a real pain. Plating or paste is the way to go! Of course on a multilayer board greater than two layers, the rivets don't work very well.
MULTILAYER PCB's A lot of people are afraid of making a multilayer milled PCB. If you can mill a standard single sided board, you can make a 12 layer board. It really is that simple. LPKF has a set of procedures on how to make 4, 6 or 8 layer boards, and then they came up with a single press method for the 6 and 8 layer boards. I never used this single press method, because I had to always deal with hidden vias or some other issue, so I could never make use of the LPKF single press method. The LPKF software BoardMaster uses "Phases" for the style of board one is desiring to make. Meaning if you are making a two layer board, your 2Layer Phase would have a list of layers based on the order of how the board is to be made. Each layer is set for a bottom view or top view and you always prefer to start with the bottoms first and work to the top layers. So all of your drilling is done from a bottom view along with your bottom layer and then flip your board over for a top layer view. The final contour route of the board is also a top view. But in a four layer board according to the original LPKF method was to take a double sided board, drill and mill it accordingly and the top layer is actually layer2 and the bottom is layer3. The board was then placed in the heat press with two pieces of single sided copper clad material and some prepreg and once aligned milled/drilled again in the order of bottom first then top layers. This process would be repeated for a six or eight layer board. Now I left out a lot of alignment stuff here, but you get the picture of how to build a basic board and flipping the thing over and over, possibly inducing error in alignment. This method severely limits how you can make your board layers as well as hidden vias. Now I want you to completely forget everything you ever learned about building a multilayer board with your equipment. I want you to just think of every board as a single sided board stacked on top of another board. Process each layer separately as if each were it's own job. Now we stack them in a sequential build according to the layout design. Then laminate the layers to make a board. Simple right! Stay with me on this. See I told you at the top of this page this is not for the beginners. I know I need some pictures, and I'll work on them one day, but for now lets use our brains. When you first import and use CircuitCam to process your multilayer job, just don't worry about all of the layers, just make sure you have some cheat sheet to help you identify all of the many layers. The only layers you really need to identify at first are BoardOutline, Top, Bottom, DrillPlated, DrillUnplated, Fudicial, TopMask, BottomMask, TopSilk, and BottomSilk layers. All other layers are going to have funny names assigned by the layout software. You can change the names later but for now keep them the way they are. BTW, you are importing all of these layers in a 2 layer assignment. At this point I paste into the job what I call Targets. Basically a large positive sign that I have that I use on all jobs that require mask/silk layers. This allows me to make my alignments for those items on the top and bottom layers ONLY. So now I make sure all my layers are aligned and make any corrections. Then I determine how many boards I need to make. So I generate the Step&Repeat function and say we want to make 4 copies of our board. I then place my Targets at the desired locations (at least one per corner of the work) and I now add into the Fudicial alignment hole layer and finally a minimum of six 125 mil diameter holes around the exterior or the job, outside of the Targets. These new large holes are going to be our intra-layer alignment holes so that we can get proper alignment regardless of the order of our building of the board. Because on this job we have to make a bunch of hidden vias between certain layers. Depending on the build requirement and intra-layer via connections we have to look to see which layers we are going to begin with. TO BE CONTINUED
Specializing in RF & Microwave Produc
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