Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

In search of knowledge

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In search of knowledge | 16 October, 2012

Hello all,

First off let me start by introducing myself. My name is Dan and I work for a contract manufacturer. During a job search I had heard from a previous co-worker that there was a packing job available at the facility where he now worked. I applied for the job and quickly received a response. On my first day I was learning the ropes and noticed that all the products that I had to pack were circuit boards. Having some knowledge in circuitry and PCB assembly, I began to name some of the components that I saw on the board I was packing and asked my instructor if the PCB would become the final product that I thought it would become. I was right, and at the time I didn’t know it, but the instructor was actually the owner of the company, and the next day I was promoted to the functional test position for one of our highest running boards at the time. The lead for that department was an older gentleman who had been working at the company for at least 15 years, and he would be my instructor for testing these particular boards. Not long after he started showing me the test procedure, I realized that he had me repeating steps and pushing buttons multiple times causing the test time per board to rise dramatically. None of the extra steps he showed me were in the test procedure documentation and I took it upon myself to alter the process from what the lead had showed me. Just by following the documentation step by step I increased the output from that test station by double. Fast forward a year and I had set up two production lines and have been moved into the engineering department as a JR manufacturing engineer. I’ve gained a feeling for what the main goal of manufacturing is, but I have a list of projects that I’ve never had any experience with. The current employees are either unable or unwilling to help me, so I have come here in search of any knowledge that you may be willing to share. My list is as follows.

1.) Create wave solder pallets for boards. (One board has very difficult specifications for positioning of 6 MOSFETs. The pallet manufacturer has told me a pallet cannot provide the specifications required.)

2.) Improve material movement. (The hardest part is getting the employees to understand and properly use the system I am trying to set up)

3.) Create an ESD program.

4.) Cost reduction (This is a huge project, and I don’t know exactly where to start. My gut tells me to trim the excess time off of operations by setting up them up so that there is less wasted time. But I always run into employees who have been doing the same thing for 20 years and are unwilling to change. Also I purchased a dross recovery system to reduce spending in that area. But of course due to budget constraints I ended up with a system that needs some maintenance and I have no experience in the operation of the unit. Same goes for the conveyors that I purchased to help move product and reduce labor at wave solder entry and exit points.)

5.) Clean up and create new routers.

6.) Set up a 2 bin system for the stock room.

7.) Time study all operations.

8.) Paperless manufacturing. (Trying to get all documents on a network so there is less time wasted searching for folders.)

9.) Repair and learn to operate a Pillarhouse Jade S-200.

There is more to the list but I can only focus on so many projects at a time. So please if you have any information that you are willing to share, it would help so much. I have no access to any real knowledge besides hands-on trial and error experience, which is only getting me so far. If you have anything helpful please share it, I would appreciate it very much! Thanks in advance guys.

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In search of knowledge | 17 October, 2012

1) Is there something your design/pcb Engineer can do to lay the array out a little better for the wave (i.e. add substrates, board thickness)?

2)What do you mean by material movement? Single piece/continuous flow.

3) Shouldn't be too hard. You first need to determine what kind of equipment you will need. Will the employees be using wrist or heel straps. You will need to test the straps every day before the start of the shift. There is plenty of equipment out there to give you some ideas. We use heel straps, conductive paint on the plant floor, grounded to steel support beams. We also use ESD mats on all the work benches. Document everything, what's required, testing, failed ESD straps (how to replace).

4) Reducing cost is an ongoing process and something that will never go away. Consider this a never ending project. But first you need to do time studies to see where your time is being spent. This needs to be done from the SMT equipment to packaging, eventually. But to start and get immediate returns, you could start from the wave, and work forward to packaging. Chances are, most of your time will be spent here and plenty of imbalance will probably be noticed.

5) Specifics. Routers?

6)Are you looking to implement a push or pull system (lean)? Kanban system?

7) Observations and a stopwatch are the simplest method. You can do a search on time studies. There is plenty of information out there.

8) Can IT assist you with this. What type of procedures and documents? Work instructions? ECOs? Work Orders?

9) Not a clue. Can you contact the mfg and get some documentation from them?

From all this, and given your current duties, I would start with the time studies (#7). The greatest saving will be to eliminate the time wasted in production, but you have to get the times first. This will help you achieve #1 and #4 as well, so I think that #7 will have the greatest impact on your operations. As far as some of your other goals, you may need to get other dept. involved to make things in production easier for all involved. Folks will come around when they see the improvements in efficiency. Keep up the good work and don't forget that it was your inquisitiveness and ingenuity that got you where you are to begin with.

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In search of knowledge | 18 October, 2012

1) At this time we do not have a design engineer. I have contacted the PCB manufacturer about changing the drill file to close up the diameter on the holes a bit. This should allow the wings on the leads of the component to rest on top of the holes instead of going through them, which would give us the correct height. Also I am going to have a pallet made to satisfy the perpendicularity requirement. So hopefully this solves all the issues. I will post results if anyone is interested.

2) By material movement I mean, when boards come out of the reflow oven and move to the assembly line and ect. I know conveyors would be ideal, but money is the issue with that. We purchased some used conveyors and i had a plan to implement them onto one of our wave solders. I managed to get the entrance conveyor and the exit conveyor to work properly, but the workstation conveyors are non-operational and I do not have the know-how to fix them. So I am kinda stuck.

3) We also use wrist straps as well as a heel strap/floor system, and we test once a day before shifts. But I see employees all the time with their feet off the floor because they are using the heel straps while sitting and not a wrist strap. So we have room for improvement. I feel I have a strong understanding of ESD and how to prevent it, but I do not know how to write up a plan or how to implement/enforce it.

4) Thanks for the starting point on time studies. I had the wave idea stuck in the back of my head since I saw the most room for improvement there. But you stating it has set a solid start point for me.

5) We have a form called a router that currently follows the job through the facility in a folder. At each operation it gets signed by the employee who did the work on the board. But our "Engineer"(I honestly don't know what she does besides yell at herself while eating at her desk. This is a whole other topic that I need help with.)made a universal router for all boards. By cleaning them up I mean to make them all very specific as to what needs to be done on each individual product. I am assuming I can eliminate extra processes once I start my time study? Let me know what you think.

6) I have only read up on kanban and lean manufacturing minimally, But I do believe I am trying to set up a simple kanban system for our stock room as well as non-inventory items. I understand the principals but I would not know how to implement it in our facility.

7) Yes this is pretty self explanatory but my question is where do I start? Do I study one product as it goes through the facility? Or do I study one operation for all the boards that pass through it? Any thoughts?

8) Yes IT will be assisting me with this. I guess I was just looking for any input anyone might have to offer.

9) Yes they could be contacted but the owner of our company does not wish to spend a lot for training, (I know that is his own wrong doing) but I would still like to get it up and running even if I have to find some way to bypass budget constraints.

Also getting other departments to help me is a real challenge. The people here do not like me because of my advancements, and will with-hold information from me. There is also a huge lack of motivation due to managements recent actions regarding our bonus system(Another long story). I am only motivated by self improvement and even that gets difficult at times. So I feel the hardest part for me is getting this place back to an efficiency that allows management to reward employees and increase morale so that I can start to get them back on board.

Reese, I thank you for taking the time out of your day to respond and help me with this. I hope you continue to provide me with insight as I do not have anyone to go to at our facility. Once again thank you.

May I ask what it is that you do?

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In search of knowledge | 18 October, 2012

2) Start with the PLC. What do the indicator lights tell you. Is your entry sensor working? Your PLC has status lights that should go on/off with the input/output conveyors. Can you be more specific about "not operational?" This is a broad statement.

3) One way to ensure folks are still grounded with their feet off the floor is to provide ESD mats for all the benches and workstations, properly grounded. There will be times when they are not touching the mats. It's not ideal, but better than nothing. As far as enforcement, hopefully you will have management to back you up and this policy needs to come from them so it has teeth. In other words, when you do come out with a policy, management is the one that needs to announce it. It sounds like they are already on board with this.

4) Yes, most of your wasted time is going to be at the back end of the production line, starting at the wave, since most of your manual handling and what not will occur at testing, assembly, and packaging, it makes sense to start there.

5) Is this a work order or work instruction? It sounds like a little of both. Can you be more specific on what this form does and what information is on it? Typically, work instructions are specific, but they are specific to a specific area of the plant. I have not heard of a traveling work instruction. The work instructions should be posted at the stations that will be doing the work, broken up, from one sequence to the next. For work instructions (travelers), we have stations set up at different sequences where they get scanned in so we can track them through the plant.

6) How to implement? That really depends on your facility as you said. We have tried lean in the past, with varying success, but it depends on your processes and the number of SKUs you have that will determine your success. I would start with one product, that flows well through the plant and has small to no batches. It will be challenging going lean plant wide.

7) For time studies, you need to study each product as it goes through the plant.

9) I'm not talking about training. The mfg might be able to give you some support and/or documentation you might be lacking. You can also try to contact the vendor you purchased the machine from. This may be before you time, but someone should know who sold you the machine.

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In search of knowledge | 18 October, 2012

2) The conveyors do not show any signs of life when powered on. No lights, no sounds, no movement.

5) The router tracks the boards movement through the facility, and it also directs the employee to the tools and work instructions required for each operation. Which at some point all the work instructions will be on computers at the workstation. Can you explain your tracking system in a little more detail? (It seems as if I am answering my own questions as I am reading yours.)

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In search of knowledge | 18 October, 2012

The conveyor will most likely be controlled by a PLC. Have you looked in the control box for one? This may help you troubleshoot it.

The work orders are scanned post-wave and pre-stock. This does not seem like something you have or need to worry about at this point.

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In search of knowledge | 17 September, 2013

9) Not sure if you ever got an answer to this. Where are you based as Pillarhouse offer free training if you visit them. For USA they are in Chicago and for UK they are just outside London. They also have plenty of documentation they can provide FOC. Any questions send me an email.

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