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Selective soldering

Views: 2748

#35747

Selective soldering | 26 July, 2005

Hello,

We currently have huge quality issues with our Inertec selective solder machine, the model we have does not pump solder, rather the solder bath is raised to the product.

We have continuing issues with bridging and non wetting of joints. We are unable to achieve our quality targets.

We would like to carry out some benchmark studies with this machine and others on the market.

Does any one have an interec machine where we can compare apples to apples, since Interec are not willing to share PPM data.

If you also know how to improve quality of the Interec please let me know.

Cheers

Crishan

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aj

#35748

Selective soldering | 27 July, 2005

Crishan,

I am not familiar with the machine you mentioned.

Do you use selective solder pallets through a wave process or is the machine a selective soldering machine (ie. where the board is moved to the solder fountain)

No matter what the process the variables are the same,as in Flux type and application , preheat and solder alloy.

With your flux make sure it is been activated correctly(preheat) and is aggresive enough to clean the board. Have you carried out an analysis of your solder alloy lately,you might have insufficient Tin which could cause your bridging.

I cant understand the supplier not helping you on this one?

aj

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#35770

Selective soldering | 27 July, 2005

Aj,

You are correct, we use pallets to hold the motherboard, an X-Y table then transports the pallet through preheat section to the solder bath.

I will check out your recommendations on the solder alloy.

Supplier is not willing to share PPM data on this machine, for quality faults, we believe this is due to the fact the machine is unsatble. We are planning to remove this machine and replace it with an Ersa Flow

Crishan

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#35801

Selective soldering | 29 July, 2005

Hello,

I am not familiar with Inertec but have some expirience with selective soldering process, My oppinion is that the wave and slective soldering are not the same game. In Selctive soldering process is very important the layout design. If use the nozzle (fountain) for soldering of PTH components the min. distnace to the sarounding SMT components must be more than 3mm, usualy 4mm. Next is determination diameter of the nozzle. Incorrect diameter can be reason for many of the bad quality rezults. About gripper systeme (X,Y table) is very important accuracy of the movement and dinamic solder flow. For example one of our machine had problems with parallelism of the table and the adjustment in Z ordinate was very critical. This issue was multiplied by the unstable PTH lead lenghts. This problems were resolvet by our automation department. The root couse was in the construction of the machine and the manufacturer (SEHO) just want provide any supprot. Control of wave high and dross contamination are also very important. Of course factors wich have influence over the quality like preheating. fluxing etc. are also important. I think that it is a good idea to make SPC study by variables of all control parameters, and next step to determine power factors. About the vendors of soldering machine. I think the best are SOLTEC and ERSA depending on prise and efficiency - big disadvantage of slective soldering systmes. Hello,

I am not familiar with Inertec but have some experience with selective soldering process, My opinion is that the wave and selective soldering are not the same game. In Selective soldering process is very important the layout design. If use the nozzle (fountain) for soldering of PTH components the min. distance to the surrounding SMT components must be more than 3mm, usually 4mm. Next is determination diameter of the nozzle. Incorrect diameter can be reason for many of the bad quality results. About gripper system (X,Y table) is very important accuracy of the movement and dynamic solder flow. For example one of our machine had problems with parallelism of the table and the adjustment in Z ordinate was very critical. This issue was multiplied by the unstable PTH lead lengths. This problems were resolved by our automation department. The root cause was in the construction of the machine and the manufacturer (SEHO) just want provide any support. Control of wave high and dross contamination are also very important. Of course factors which have influence over the quality like preheating. fluxing etc. are also important. I think that it is a good idea to make SPC study by variables of all control parameters, and next step to determine power factors. About the vendors of soldering machines: I think the best are SOLTEC and ERSA depending on prise and efficiency - big disadvantage of selective soldering systems. Regards

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crishan

#35817

Selective soldering | 31 July, 2005

Thanks you for the information LUPO, specially with component minimum clearance. I will also check the XY table for movement accuracy.

What specific parameters do you check with your SPC charts.

Thanks

Crishan

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LUPO

#35968

Selective soldering | 8 August, 2005

Hi,

So about SPC by variable: flux drop-jet size, preheating, high of solder flow. attributes: soldering defects. I hope that the info will be helpful.

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