Panelizing at seeed

[papo]

Hello

I recently started to use seeedstudio for prototypes of private projects and so far everything is fine. I noticed that they appear to offer some panelizing service. That way, I could get my ~100 mm x 50 mm PCBs for half the price panelizing them on 100 mm x 100 mm panels. Sadly, not being able to really discuss issues with the fab house as usual, I feel a bit confused. I was about to ask for clarification in the forum over at seeed, but several people asked this already and seeed keeps referring to this page which isn't exactly helping. So maybe somebody can share some experience with the following question:

The source for my confusion is that you apparently get the whole panel and not separated boards. That's what I would expect but as far as I can tell they don't V-cut the thing. While this is not really a problem, why would they care about whether I am ordering one big design or two small designs (or two different designs, for that matter) as long as I take care of copper clearance etc.?

Regards and thank you

Matt

[Psi]

If you're referring to the rule
"there should be no more than 5 sub-boards on a whole board to fit the size"

It maybe because;
- Large numbers of sub-boards means lots of drill holes which is slower and needs care with the alignment. Too much time for a cheap pcb.
- They don't want people to save 'too' much money using this option to make 100's of tiny pcbs and want people to use there other more expensive services for that.

[poorchava]

I think this is simply economic/business plan issue. They actually don't charge extra for large number of holes (although I'm usually using itead than seeed). They don't even charge extra for routing your board to some funny shapes.

If your design is rectangular, then just leave yourself some extra clearance between boards and separate them with a saw/paper guillotine/boxcutter/bandsaw/milling machine or whatever else you have at hand.

I'm making my designs such, that there is 1mm keepout from all the edges which will be cut (just to be on a safe side and not break some traces by accident). I'm using my cnc mill to separate those. Tool I found to be the best for this job is 3mm 6-flute serrated edge fishtail endmill with 1/8" shank runnig at ~15k rpm. I think this give the best results because it gives smallest feed/flute ratio and therefore exerts smallest force upon pcb and gives nicest finish.

So I'm generally stuffing 4 copies of 23.5x23.5mm board with 1mm keepout around the edges on itead/seed 50x50mm format.

I've seen people placing for example long row of pin headers between boards, but while chinese are quite cheap, they are not dumb and will notice what you are trying to accomplish.

[Christopher]

I make homemade boards, but the same applies and I've done it before with seeed:

Put all the boards into one CAD file, with silkscreen separating them, then snip yourself with a PCB gillotene (VERY handy) or for small boards (2") a pair of tin snips works wonders too.

Don't bother using hacksaws or other bladed saws, the blades will wear very quickly and the dust (although smells quite nice) is horrible,

They won't cut them out for you, just around the main dimension.

[shebu18]

I had a pcb of 5cmx2,5cm. I put two on a 5x5cm PCB with a white silkline in between for guidance. Seeed sad that they do not cut it but i got mine cut in two.