PCB stuffing/man. ref. material

[MacGyverS2000]

I'm looking for any information you guys might have on PCB stuffing/manufacturing. I've been stuffing all of my boards up to this point, but will be moving to higher quantities, which means letting someone else do the work. Online papers and such is perfect...

For example, how much might it add to the cost if I mix SMD parts and through-hole? I use mostly SMD, but certain components, particularly connectors, are through-hole...do these need to be soldered by hand after the SMD parts have been IR or wave soldered?

Vias under components weren't a problem when the PCBs were hand-stuffed, but I know wave-soldering will leave flux stuck under components. Let's assume I didn't know stuff like this and point me in the right direction...

Thanks!

 

[Comcokid]

If you have a product that is just reaching the need for a outside assembly house, I will assume your volumes are still low, and you are not looking for a super-high volume assembly house.

Most of the question you have can be answered by, or are issues your assembly will deal with on a regular basis. They can also provide good feedback on what might be best to change in your design before you arrange for production. The answers to these questions may vary depending upon what kind of equipment they have and your quantities.

If you don't have, or have not located an assembly house to use, talk to the local component sales distributors and reps - they will know the places located near you. For a product just going to production, having the assembly house close by helps. Talk and visit with them - they can be a good source of knowledge, and having your product designed to make the best use of their assembly capabilities with save you trouble and money in the long run.

 

[sreid]

For small to medium volume the usual assembly process is

1) Pick and place backside components and reflow solder.
2) Pick and place front side components and reflow solder.
3) Hand insert/hand solder through hole components.

The backside components must be light enough to stay on from surface tension in the second reflow. Small chip resistors and capacitors are OK.

If the components are all on the top side then the through hole components can be wave soldered. To stop solder fountaining through vias they should be tented (solder mask covers the vias).

 

[felixc]

If you have no BGAs, you can even find one-person shops that can do all your work at a price that competes with bigger shops, if the volumes are low, as thery have little overhead costs. This is how I get my prototypes made. Up to 25 boards, mixed technology.
I agree with Comcokid. Talk to your local parts suppliers. They usually supply parts to the local assemblers so they will happily recommend you their favorites (I did not say the best ones for you, so do shop around).

 

[MacGyverS2000]

I'm looking at a reasonably small board, say 1.5" x 3", with SMD components on front and back, through hole connectors on one end. I can do a handful a day and still leave myself plenty of time for design work on the next project, but anything beyond that and it's a massive time sink. I figure about 500 for a first run, hopefully several thousand or more per year once things get going.

I have a feeling this will be done overseas due to the sheer cost difference between domestic and foreign labor (initial quotes are definitely confirming that). For example, a simple run of 500 was rough quoted at $1.50/board for stuffing and electrical testing. This was from a Canadian shop who sends most of their work to China. I'm sure the price would go quite a bit lower as numbers increased and I began dealing directly with the shop.

I just want to get the best deal possible, and that doesn't always mean the cheapest. Any changes I can make to the board design now for production will seriously help me in even the near future, not just the long run. I'm just afraid that working with a local shop (or even just domestic) would be cost prohibitive, regardless of the design advice I might receive in return.

But I like to keep my options open. If anyone can suggest a quality shop in the southern Florida area, say anywhere between Orlando and Miami, I'm all ears.