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SMT electronics assembly manufacturing forum.


through hole today

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#70724

through hole today | 9 September, 2013

Hi Everyone, I'm looking for some feedback about through hole assembly requirements today vs. yesteryear. As I see it, there are two main categories...legacy through hole and new through hole with mixed technology. The legacy stuff is older designs typically aerospace and defense and because the designs are old they may be predominantly through hole and thus many different through hole parts on each assembly. The newer assemblies are predominantly SMT but then there is the likelihood of a few "pesky" through hole parts to deal with (usually power devices or connectors etc.). I am wondering if my assessment is correct and if so what would be the ideal method to address the "new" through hole assemblies. Any and all comments are welcome. I would like to know as much as possible about the assemblies such as average number of unique through hole parts, average PCB size, industry the PCB is intended for etc. Thanks is advance to all contributors.

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#70738

through hole today | 10 September, 2013

Most of our product are mixed technology. I don't consider thru-hole components as "pesky." Perhaps from a manufacturing point of view they are due to the extra handling and machine requirements. But from a reliability stand-point, thru-hole is much better than SMT in certain circumstances. Power terminals for instance, or any type of header/connector for that matter. SMT for these parts brings with it a few production issues: solderability, skewing, and lifted leads. I prefer thru-hole components in these applications simply because they can be built much more reliably and are more durable. I don't believe thru-hole will be completely eliminated. We do have some product that are 100% SMT and we have the production issues with these boards of those mentioned above. We are a mfg of security alarm systems and I have seen DOA returns with terminals that have been torn from the pads as I'm sure you have as well. Of the boards that are mixed technology, I would say it's 90/10, SMT to thru-hole on most product. The components we use that are thru-hole are: large terminal, small headers, connectors, large relays, power transistors, regulators with heatsinks, polyfuses, battery holders, and large electrolytics. You just won't get away from it completely on all product.

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#70740

through hole today | 10 September, 2013

Hi Reese, Thanks for the feedback. So you have a fair amount of assemblies that are new designs with 10% through hole parts. Are these parts inserted manually? What is the soldering process?...wave solder?...selective solder? Do these components require clinching or trimming after insertion? If so, what method do you use? If they are inserted manually, is there issues with the quality? Would some type of assembly guidance be helpful (light guided for example)? I have a lot of questions so thanks in advance if you can reply.

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#70741

through hole today | 10 September, 2013

Most of the PTH components are manually inserted. Some are auto-placed by our UIC machine. The parts are preped before install, so there is no need to trim the leads afterwards. The boards go through wave solder. The UIC machine has a clincher on it. For manual insertion, the leads are not clinched. We don't see too many issues with quality, but occasionally we do have mis-inserted and wrong parts installed.

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#70773

through hole today | 11 September, 2013

Hi Reese, The UIC machine is (was) good for higher volumes. Do you think these machines are less appropriate for smaller lot sizes and PCB's with just a few through hole parts? Also, are the UIC through hole machines still fully supported with ample spare parts inventory? What is the deciding factor as to whether a component will be manually inserted or auto inserted on the UIC machine?

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#70779

through hole today | 11 September, 2013

"Do you think these machines are less appropriate for smaller lot sizes and PCB's with just a few through hole parts?"

That depends. It will still save time if your lot sizes are small, as opposed to hand placement. I would not recommend buying and old UIC to do this for small lot sizes; especially, if your designs are leaning more toward SMT.

"Also, are the UIC through hole machines still fully supported with ample spare parts inventory?"

No. Like any older machines, the parts get more sparse the older they get. There are some parts on these machines that cost about as much as the machine is worth because of lack of availability.

"What is the deciding factor as to whether a component will be manually inserted or auto inserted on the UIC machine?"

If all the slot locations are taken up, the part may be hand-inserted. These are typically the lower volume components. Also, the part may not be able to be placed manually as well and would require hand-insertion.

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#70786

through hole today | 11 September, 2013

UIC still manufacturers new thru-hole machines. Both axial and radial insertion models are available. They stopped making the multi-mod dip inserters in '91 or '92. And parts are easily acquired for any older models, there were a ton of machines out there at one point and used spares are easy to find if universal does not have the part. As far as justifying the cost to purchase an insertion machine, I believe universal claimed you save 4 secs per insertion, that number did not take into consideration set-up time. After performing some time studies about 10 years ago I came up with 8 seconds savings per insertion which included set-ups. If you aren't hand installing at least 400,000-500,000 axials or radials per year than buying a rad8 or vcd8 wouldn't be justified. You could get an older rad5 or vcd5 series around $30 grand and you could justify it if you plan on inserting at least 300,000 parts. That would be for a 1 yr payback.

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#70787

through hole today | 11 September, 2013

I forgot to mention the new vcd and radials go for around $230,000 each with only 20 stations. You can buy nice used vcd8 and rad8's between $60,000-$75,000.

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#70808

through hole today | 12 September, 2013

Wow, great information! I have a feeling you are talking about some predominantly through hole assemblies with mostly common components. In this case fully automated solutions make sense if the volume is there. But these machines cannot do everything, correct? Is there still components that need to be hand inserted due to limitations of the auto inserters such as connectors, headers and oddball power devices that cannot be SMT (in the case of mixed technology assemblies)?

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#70809

through hole today | 12 September, 2013

Yes. Typically terminals, large relays, displays, parts with mounted heatsinks. This is typically what you see on hand-insertion lines. Other parts with specialized packaging may not be able to be auto-inserted either. Most axial and radial leaded parts can be.

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#70810

through hole today | 12 September, 2013

We service the defense market with board size typically 2x5 up to 7x14. The typical TH parts are capacitors, connectors, large semiconductors, high power resistors, etc. There are typically 10-20 parts on each PCBA and represents about 10% TH vs SMT. Volume is low/high mix.

Obviously fully automated insertion is not justifiable as previously noted. A semi-automatic Contact Systems CS-400C works well for us. Leads must be formed beforehand and then put into rotating trays on the machine. After insertion, the machine cuts the lead and clinches it, keeping it in the board until soldering (manual or machine). A used model C can be had for about $2k. Software is available to program on a PC and generate documentation.

There are still some parts that must be manually inserted at the bench such as large power semiconductors, very large capacitors, toroids and bobbin wound transformers, turret terminals or other hardware,and connectors. The sequence is: CS-400C component insert >> manual insert any remaining odd form components >> selective solder or hand solder if needed.

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#70811

through hole today | 12 September, 2013

Hi Dean, Thanks for the feedback. I suppose I should reveal the nature of my query. Contact Systems was founded by my father back in 1970. I worked there from 1983 until we closed the doors back in 2009. I acquired the assets and intellectual property of Contact Systems and started Versatec. We specialize in support and remanufacturing of Contact Systems equipment. I was directly involved in the development of the CS machines including the CS-400 series through hole machines. The durability and reliability of the CS-400 series machines has allowed those machines to remain active for decades. Production of the C model ceased in 1990 with the introduction of the D model. So your C machine is at least 23 years old. So my reason for starting this thread is to get a feel for what would be the next evolution of a machine for low to medium volume through hole assembly. The CS-400C, D and E machines are great machines and there are still some around but they may not be optimum for the types of through hole assemblies being built today. From your perspective as a military contractor, what would you change about the CS-400 C, D and E model machines? Some ideas to get the juices flowing.... Windows OS? In line machine that you could put side by side and slide the PCB to the next station on a flat conveyor? Insert everything on the machine including the "large power semiconductors, very large capacitors, toroids and bobbin wound transformers, turret terminals or other hardware,and connectors"? Thoughts about the cut and clinch...? Also, what are your thoughts about PCB size and on line component count? Please, anyone with input feel free to express your opinion.

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#70814

through hole today | 12 September, 2013

Good ole contact cs-400. I worked at two different companies that had these machines, all I believe were E's except 1 C. One place had one and the other place had 4 of them. Dont take this personally, but thank god my current employer doesn't have any of them. I had to perform the maintenance on them and there desisn was terrible if you had to get into the cutter area. I could not count on both hands how many times I had remove the table to get into the cutter assembly area. A real pain the a$$. And if werent for the nice aegis interface we had, I thought programming sucked too. One of the places we were building military and aerospace products and the lead lengths had to meet class 3, so the contact was able to perform that short of length, but the low profile blades had to be used. The thicker lead components were not then able to be cut and clinched. My ideal vision of a modern contact style machine would be setup like the Robotas brand machine with a cutnclinch that moves in the x & y which the robotas is missing. Better cutters with more capability in one set so a wider variety of leads could be cut without changing out cutters would be good too. If universals polaris feeders weren't so expensive than i think it would be the thru-hole machine of the future. It can place just about anything you want and it has a cutnclinch that moves, but custom feeders can run into the tens of thousands. I was quoted something sick, like 15-20 grand for one feeder. My 2 cents.

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#70820

through hole today | 13 September, 2013

Hello Action_101,

We are pretty much on the same wavelength as far as moving the cut and clinch and leaving the board stationary. It is the first I have heard about the cut and clinch being difficult to work on but you worked on them so your opinion is important. The machine was developed back in the 80's with a DOS OS and I agree the programming is somewhat laborious. That would all be a lot slicker in an updated windows version machine. The cutter is tough to design so that it can cut thick leads while cutting leads short and keeping a small "footprint" so as no to disturb any SMT components on the underside of the board. The cut and clinch takes a lot of abuse. I would like to know some opinions about what lead diameters need to be cut (max) and what minimum lead protrusion is acceptable. Also, any more thoughts from anyone about improvements is welcome.

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#70840

through hole today | 15 September, 2013

I would be happy to add programing of the CS400 to my program PCBSynergy gregp. I have added about 80 SMT machine formats to the program to date. All built by reverse engineering. You only need to send me some example formats or better still your original DOS program and some example input formats, and I can usually generate a file within a day. Anyway If you wish to contact me. My web page is

http://members.iinet.net.au/~sarason/

where you can find my email

regards sarason

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