Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


LASER SOLDERING

Views: 3245

dougs

#40904

LASER SOLDERING | 10 April, 2006

Hi,

Just wondering if anyone has any experience on any of the inline laser soldering machines available, benchworks, PMJ cencorp, Seica. Any info on any of them would be great.

cheers

Dougs

reply »

#40917

LASER SOLDERING | 11 April, 2006

Hi Dougs

I worked a bit a few years ago with a diode type soldering laser. I found laser soldering very application specific so make sure you send samples off to differnt companies to see actual results. You can get good results with a laser system, just takes some work.

Pros: Isolated heat area, quick to respond, target solder joint, flexible (if good software and laser control), repeatable

Cons: The quick ramp rate can cause solder balling (flux burn off and scatter solder, ie... cleaning?? ), can burn some surface finsishes and parts very easy, requires good operater/engineer to program/run system (not entery level job)

Systems out there today may address issues above but do your homework. thanks

reply »

#40919

LASER SOLDERING | 11 April, 2006

Dougs,

Make sure they use the same solder that you plan to use. In my case they were unable to get acceptable solder joints with our solder. We use no-clean P1 flux in our cored solder. So I recommend you try before you buy. Jerry

reply »

Chunks

#40924

LASER SOLDERING | 11 April, 2006

Depending on model and/or series, each one has it's own specific manufacturing guidelines you must meet in order to get a successful solder joint. Then you must couple that to what your soldering process is. Assuming you are talking all thru-hole, there is a host of things to look for.

Things to consider:

Size of pad to laser. Laser can through a lot of heat out. You may need to adjust pad size for the type of laser you�re looking at.

Masking: You�ll probably have to pull this further back than normal as to not to burn it.

Keep out area. Depending on the machine, the angle of attack and heat required to melt the joint may require you to keep parts away from this area.

Pre-heat. A lot of selective solder people forget about preheat. If they do, then they also forget about the delta T from preheat to soldering station. This can be critical for top side wetting.

Board travel. A lot of people forget this too. Small boards may not travel well on robotic arm type machines.

Flexibility. Can the laser handle a variety of different part sizes?

Reflecting the beam. I had a solder joint that would melt and act like a mirror to the laser. And not allow it to melt 10%.

Constant alignment. If possible, find a machine that uses fids or tooling holes and not a board edge for alignment. Edge of board to copper does change from lot to lot. This may be enough to cause problems.

reply »

dougs

#40963

LASER SOLDERING | 13 April, 2006

Thanks all for your comments.

reply »

George

#41036

LASER SOLDERING | 18 April, 2006

I do not know what kind of products you assemble but don't forget about the cycle time. You probably could accomplish more and faster with a custom nozzle (solder fountain style)for a specific application than point-to-point soldering as laser. I evaluated beamworks and others out there...did not work for us....with large ground planes on the PCB, cycle time just became unrealistic.

Regards, George

reply »

dougs

#41050

LASER SOLDERING | 19 April, 2006

Good point about the cycle time, we've had a think about this issue, we are set up mainly to do small batch sizes, the reasoning for thinking about laser soldering is that there is no requirements for wave solder tooling, on a batch of 50 boards or so we're not always able to get the customers to pay for wave pallets, we have also considered point to point wave soldering, ersa versa flow type machines, i'd think the laser would have lower running costs but am unsure yet as to the capability of the laser systems, are there component types that the laser just can't handle or are they pretty versatile?

reply »

George

#41059

LASER SOLDERING | 19 April, 2006

If you are not OEM I would evaluate a chosen laser machine carefully. If possible, go and run some PCB's yourself at the manufacture's place before you jump into conclusions. If your work orders are small and very different, it might take a while for you to fine-tune the program every time, could you afford this? also depending on your assemblies, you need to consider the wattage required, 30, 60w, etc. About running costs....Do you know how long the laser diode lasts? After a number of hours-use it starts to degrade and eventually you will have to replace it. This is something that laser selective equipment vendors do not mention if you do not ask.

This is my 2-cents and my opinion...Good luck on you project

George

reply »

convection smt reflow ovens

Electronics Equipment Consignment