Suggestions for company transition from mainly leaded to smd

[Cicero]

Hi there guys,

Sorry I've been a little quiet in here recently, I've been pretty busy with an embedded project which has been taking all my time.
But, this is a more business advice type question and some of you may have some good experiences and suggestions:

I'm in the UK (now), and joined a small but growing company that designs products with primarily leaded pcb assemblies.

More recently, especially with me on board, we are moving more and more into surface mount in an attempt to modernise and also cut costs on some of our more high volume items (we're still talking hundreds of boards, not thousands). So all in all we are still a low volume manufacturer.

At the moment, we are in a kinda transition phase, we hand solder our smd devices (just IC's at the moment) onto the boards, and then assemble the rest by hand.

My previous experience has either been in a company that contracts out all assembly (which is an obvious option), or has their own pick and place, reflow oven, and wave bath etc.

At the moment we have NO smd equipment. I would love to have our own machines, but its an all or nothing situation, you can't just buy one oven for example, you need the screening equipment, pick n place to go with it all.

How would you suggest we tackle a transition to primarily smd? Have any of you been involved in a situation like this?

My gut feeling, is that our only option is to contract out our manufacturing. Start with our highest volume board, and run from there. Its only worth investing in new equipment when you can be certain you'll be running enough boards through them to make it worth while.

I dunno, just throwing it out there, interested in whatever input you can offer.

 

[cowboybob]

Cicero,

In business, it's always a "return on investment" decision (or it should be...), so your gut feeling is correct. From that experience any further decisions can be made.

For instance, Apple hasn't made any of its own products since the Apple I.

 

[KeepItSimpleStupid]

Even "hand solder" SMD has different processes: You can do the iron or a small mask, squeegee and hot air tool.

If you contracted out, does it make sense to invest in being able to re-work the boards?

 

[spec]

I worked for a large electronics company at a division which only had small production runs of, may be, 100 off max. We had the equipment and skilled wiremen to do hand soldered of surface mount, including ball grid array (BGA), which would be used for a run of say five boards. Higher quantities would be contracted out. But, as Keep says above, you also need to have in house skills and equipment for development and corrective work.

If you are subcontracting out, it is vital to investigate your contractor because they vary from awful to simply brilliant. If you can get a firm within easy traveling distance so you can visit to resolve any problems quickly the better. Incidentally, the cost of the service and the quality were not related as with many cases in life.

When subcontracting it is essential to get the contract conditions established in your favor but, just as important, you need to have a well defined and managed documentation system with rigorous configuration control.

Be wary of getting the suits involved in the interface between engineering and the subcontractor or it can end up as a meeting/lunch merry go round.

We had big problems with contractors at first, but then we found a local firm who could not have been better.

About having your own in-house surface mount automatic assembly, make sure you consider all the costs not just the initial purchase: training, calibration, set-up, maintenance, health and safety, management, documentation, etc etc.

We had a small through hole production facility complete with solder wave and radiated heat and it was a complete disaster. It cost the earth and took up a large area of valuable factory space. It was only turned on once a month so that a reasonable quantity of work could build up.
This meant that there was typically a wait of up to a month before a board could be made. Then there was board inspection to get through. Often the facility would be out of service for repair, maintenance, operator training, operator sickness, and on and on.

spec

 

[Cicero]

Thanks for the input guys.

spec, exactly my worry with having our own equipment. Even if we grew to triple the size, we wouldn't run our machines every day which just seems like a waste. Feel free to drop local contract manufacturer recommendations if you're in the UK, we are situated in Surrey btw.

We have skills in-house to solder most things, so I'm not worried about development, although rework might be another matter, so I'll look a bit more into that.

 

[spec]

Thanks for the input guys.

spec, exactly my worry with having our own equipment. Even if we grew to triple the size, we wouldn't run our machines every day which just seems like a waste. Feel free to drop local contract manufacturer recommendations if you're in the UK, we are situated in Surrey btw.

We have skills in-house to solder most things, so I'm not worried about development, although rework might be another matter, so I'll look a bit more into that.

Hy Cicero,

I retired in 2003 and things have changed a bit since then so I can't really help with a recommendation. I would think that in Surrey you would find quite a few good companies, but they may be a bit expensive compared to upt North for example.

spec

 

[schmitt trigger]

Cicero
when dealing with low volume SMT assembly another problem to consider is that the expensive solder paste has a shelf life.

Additionally, many components have MSL ratings higher than 1, which means a rigorous storage of the unused reels, or baking them afterwards.

There are many more process controls with SMT as compared to TH. Your technicians and engineers should be better prepared.

As Cowboybob mentions, eventually a careful cost accounting analysis is required. It will tell you whether to keep your own assembly capabilities or not.
In the company I work for, it was decided to farm out SMT assembly because it had reached the point it was not cost effective.

 

[Cicero]

Cicero
when dealing with low volume SMT assembly another problem to consider is that the expensive solder paste has a shelf life.

Additionally, many components have MSL ratings higher than 1, which means a rigorous storage of the unused reels, or baking them afterwards.

There are many more process controls with SMT as compared to TH. Your technicians and engineers should be better prepared.

As Cowboybob mentions, eventually a careful cost accounting analysis is required. It will tell you whether to keep your own assembly capabilities or not.
In the company I work for, it was decided to farm out SMT assembly because it had reached the point it was not cost effective.

Ah yes, baking components, haha. Many strange issues with that in the past.

Thanks for the insight.

 

[large_ghostman]

My own thoughts are..............If your company is growing and has a good name then invest, it dosnt matter who solders the board because at the end of the day its your company name on. Personally I would like any mistakes and failures to be my own and not a contractors, investment is expensive but a ruined reputation costs alot more. You can buy part reels and maybe talk to other small manufactures to see if you have a cross over in parts, dosnt hurt to talk to them and see if you can share inventory costs etc. Even manufacturing equipment.

It seems the world is becoming insular, as long as your not in direct competition then most small businesses would likely to be happy to help each other. Just a thought and keep in mind my age and experience (zero for one and slightly above zero for the other).