UK assembly of large PCBs?

[Mike]

Looking for recommendations for a UK or European assembly house with something bigger than an RV, who can do large PCBs - at least 500mm, the bigger the better. SMD only, one side only. Will be a 1-off job of about 200 boards.
Only one I've found so far is Tioga at about 520mm max, but haven't asked around very far yet.
I know about lueberg but suspect they may be expensive. http://lueberg.de/uploads/pics/Sonderfertigung_1_01.jpg

[Gopher]

An Essemtec paraquda has a place area Max. PCB size 600x470 mm/ 23.6x18.5" and I b believe you can break the rules a little and have some of the board extend into the feeder bays  provided they are not needed....

Soumac.co.uk (low volume specialists) has one of those, along with a whole fleet of other Essemtec machines some of which may be the larger board ones. Could be worth a try...

Anybody who specifically mentions lighting/signage is also a good bet.

A subcontractor who has a Vivo?

500mm apply to X and Y or just one of them? If its one dimension then you could take your pick of many including  Wilson process systems, I suspect a healthy quotient of subcontractors with MyData or Europlacers can help you too http://www.danlerscem.co.uk/ was one such site it was suggested I might visit to see one in action. They even have a MY500 printing machine I believe

[Gopher]

http://www.key-tech.co.uk/ a suggestion from a supplier............

[phonoplug]

You might want to consider the stencilling issue with a board that side too. What sort of pitch are the finest parts? Is it all LEDs?

Please don't say you have 0.5mm pitch chips at both extremes of the panel/board!

[Gopher]

If they can handle the board that size I'm sure they can print and place accurately right across it. Such a contractor would almost certainly be using a fully automated printer with 2d paste inspection etc. You would be looking at a 29" standard stencil size which is quite common these days .If they had a MY500 they wouldn't even be using a stencil. Handling is the trickiest bit with big boards which is I understand is solved for boards with BGA's etc by building reinforcement into the pcb itself. Now if the board needed a flo-wave process too, then things would get expensive as you might need custom carriers, shields and other paraphernalia to get it through the process intact. however for every expert who says you need these things there will be 2 who say they don't bother and have no issues.

[Mike]

You might want to consider the stencilling issue with a board that side too. What sort of pitch are the finest parts? Is it all LEDs?

How did you guess.... It's a 1.2 metre 24x24x24 cube 3d LED display, which splits nicely into six 400x600mm boards per plane.

Please don't say you have 0.5mm pitch chips at both extremes of the panel/board!

Well although the LED drivers are available in 0.5mm QFNs, and I'm sure my client would like to trim a few mm off the borders, I'm insisting on sticking to 1mm pitch SO-24's to be safe.

[phonoplug]

Why so big? Why not keep it at the 600x400 size? Surely making the panel so large really restricts your choice of bare PCB supplier, assembly supplier and makes stencilling more difficult that it needs to be.

A few years ago when I was doing a lot of LED sign designs we used some large panels (though small in comparison - about 600x450mm). We needed the large panels as basically there was only one of everything so there were some savings in making the panels large to reduce the PCB tooling costs and number of stencils. Even at that size though it began to limit supplier options, and so we wouldn't have gone any bigger.

If you are making many of the same thing, then most of the advantage of having big panels is lost. Surely the increased costs of limited suppliers that have large processing equipment outweighs the extra pasting cycles etc from having smaller panels.

Just my 2p worth anyway...

[Mike]

Why so big? Why not keep it at the 600x400 size?

..er we are - a 3x2 layout of 400x600 panels to make a 1.2m square.
So far Soumac is the only place in the UK I've found that can do panels this big (Thanks Gopher!) - most places stop somewhere between 450 and 550mm.
That extra 50mm makes a significant difference to this project - we looked at doing it as 3x3 smaller 400x400mm PCBs, but going to 3x2 saves about 4500 interconnect signals over the 150 board run. It's a 1-off job so choice of suppliers isn't a major deal.

[phonoplug]

Ah, mis-understood. I thought you had a panel that was 1.2 meters.

I know a good company in italy that could do the job if you haven't already sorted it. They are called IME, and the guy to talk to is Alessandro Iori (he speaks English). Anyway if its still of interest I'll dig his email out. Let me know.