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Setting up solder material evaluation (suggestions?)


K

#11589

Setting up solder material evaluation (suggestions?) | 3 May, 1999

I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I will be evaluating :

1. Liquid flux, for wavesolder (sprayed in some machines foamed in others) 2. solder paste for SMT assembly

With the hope of having one supplier, and same chemistry throughout the line I will also be evaluating Roll Solder for handsoldering.

If any of you have been through this type of an effort I would appreciate any information & suggestions you may have.

� Existing papers/reports? � Material parameters measured? � How was the experiment set up? � Did supplier aid in the measurements? � Any other info.

Thanks;

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#11590

Re: Setting up solder material evaluation (suggestions?) | 4 May, 1999

| I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I will be evaluating : | | 1. Liquid flux, for wavesolder (sprayed in some machines foamed in others) | 2. solder paste for SMT assembly | | With the hope of having one supplier, and same chemistry throughout the line I will also be | evaluating Roll Solder for handsoldering. | | If any of you have been through this type of an effort I would appreciate any information & suggestions you may have. | | � Existing papers/reports? | � Material parameters measured? | � How was the experiment set up? | � Did supplier aid in the measurements? | � Any other info. | | Thanks; | Kelly:

1 Other than it makes soldering materials sales people happy, there is no reason to buy all your soldering materials from one supplier. 2 The following specifications are a good starting point for defining your soldering materials:

ANSI/J-STD-004, Requirements for Soldering Fluxes ANSI/J-STD-005, Requirements for Soldering Pastes ANSI/J-STD-006, Requirements for Electronic Grade Solder Alloys and Fluxed and Non-Fluxed Solid Solders for Electronic Soldering Applications. You can buy them from a variety of locations including IPC.

3 Phil Zarro, ITM (someting or other) published a good "process document" for assessing solder pastes in a trade journal recently. You might be able to find it at his site or email him from his site and ask him for a reference or a copy.

Good luck

Dave F

reply »

#11591

Re: Setting up solder material evaluation (suggestions?) | 4 May, 1999

| | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I will be evaluating : | | | | 1. Liquid flux, for wavesolder (sprayed in some machines foamed in others) | | 2. solder paste for SMT assembly | | | | With the hope of having one supplier, and same chemistry throughout the line I will also be | | evaluating Roll Solder for handsoldering. | | | | If any of you have been through this type of an effort I would appreciate any information & suggestions you may have. | | | | � Existing papers/reports? | | � Material parameters measured? | | � How was the experiment set up? | | � Did supplier aid in the measurements? | | � Any other info. | | | | Thanks; | | | Kelly: | | 1 Other than it makes soldering materials sales people happy, there is no reason to buy all your soldering materials from one supplier. | 2 The following specifications are a good starting point for defining your soldering materials: | | ANSI/J-STD-004, Requirements for Soldering Fluxes | ANSI/J-STD-005, Requirements for Soldering Pastes | ANSI/J-STD-006, Requirements for Electronic Grade Solder Alloys and Fluxed and Non-Fluxed Solid Solders for Electronic Soldering Applications. You can buy them from a variety of locations including IPC. | | 3 Phil Zarro, ITM (someting or other) published a good "process document" for assessing solder pastes in a trade journal recently. You might be able to find it at his site or email him from his site and ask him for a reference or a copy. | | Good luck | | Dave F | | Hi Kelly,

Qualifying new process chemistries is a pain in the butt, but a real good thing to do.

When it comes to bar solder, the IPC spec is pretty broad. Most manufacturers have several grades of bar solder: stuff that meets IPC, stuff that's slightly better, and high purity stuff for tight-process window wave soldering or hot air levelling. And the spec does not address dross inclusion in the bar. Yep, that's right - bar solder comes with dross already in it, so as soon as it melts it floats to the top of the pot and you skim it off. There's a dross inclusion test you can perform to evaluate dross inclusion. When I did it, I found some sizable chunks of crap (3-5mm) in solder that was suppoed to be very pure, in addition to powdery oxides. I'll send you a copy of the bar eval.

With flux, there's a lot of good no-cleans out there that can handle most boards. There's a few that can handle the really tough boards. My approach on the flux is to figure out what's important - topside fillets, residues, solderballs, etc - for your application. For example, I couldn't tolerate tacky residues because some of my boards have keypad contacts. But the ability to foam the flux doesn't mean squat to me since I have sprayers. Set the criteria, bring the companies in for trials, and see what you like best. When you're settling on a flux, get the SIR numbers from the manufacturer. Many will just offer "pass" on their spec sheets. I don't like that; I want data to see by what margin the product passed.

On paste, I think Phil Zarrow's method that Dave mentioned is the "27 board challenge" devised by AlphaMetals. It's basicaly a print-life and tack-life test that really pushes the pastes. Indium has a similar test. We used the 27-board challenge here when we qualified new paste last winter. The info should be available on Alpha's website.

For hand solder, we were in the middle of qualifying new product when they announced that they were shutting our factory down, so we never finished it. We brought in about a half dozen manufacturers and put them to the test with our hand solderers. Of course everyone liked different products, but the predominant favorite among the real eaxperienced solderers was Aim, the majority of the other people liked the Alpha.

I found that one of the most important parts of qualifying the new chemistries is getting the people involved. By getting the technicians and operators involved in the process, you get valuable input on things you might not notice, you get the buy-in from them when you change the process, they take more ownership, and you get a lot of help with a huge task. Then, the next time you update, you can call on the people who are already familiar with the qual process and it will go much more smoothly.

Good luck!

Chrys

reply »

#11592

Re: Setting up solder material evaluation (suggestions?) | 10 May, 1999

| | | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I will be evaluating : | | | | | | 1. Liquid flux, for wavesolder (sprayed in some machines foamed in others) | | | 2. solder paste for SMT assembly | | | | | | With the hope of having one supplier, and same chemistry throughout the line I will also be | | | evaluating Roll Solder for handsoldering. | | | | | | If any of you have been through this type of an effort I would appreciate any information & suggestions you may have. | | | | | | � Existing papers/reports? | | | � Material parameters measured? | | | � How was the experiment set up? | | | � Did supplier aid in the measurements? | | | � Any other info. | | | | | | Thanks; | | | | | Kelly: | | | | 1 Other than it makes soldering materials sales people happy, there is no reason to buy all your soldering materials from one supplier. | | 2 The following specifications are a good starting point for defining your soldering materials: | | | | ANSI/J-STD-004, Requirements for Soldering Fluxes | | ANSI/J-STD-005, Requirements for Soldering Pastes | | ANSI/J-STD-006, Requirements for Electronic Grade Solder Alloys and Fluxed and Non-Fluxed Solid Solders for Electronic Soldering Applications. You can buy them from a variety of locations including IPC. | | | | 3 Phil Zarro, ITM (someting or other) published a good "process document" for assessing solder pastes in a trade journal recently. You might be able to find it at his site or email him from his site and ask him for a reference or a copy. | | | | Good luck | | | | Dave F | | | | | Hi Kelly, | | Qualifying new process chemistries is a pain in the butt, but a real good thing to do. | | When it comes to bar solder, the IPC spec is pretty broad. Most manufacturers have several grades of bar solder: stuff that meets IPC, stuff that's slightly better, and high purity stuff for tight-process window wave soldering or hot air levelling. And the spec does not address dross inclusion in the bar. Yep, that's right - bar solder comes with dross already in it, so as soon as it melts it floats to the top of the pot and you skim it off. There's a dross inclusion test you can perform to evaluate dross inclusion. When I did it, I found some sizable chunks of crap (3-5mm) in solder that was suppoed to be very pure, in addition to powdery oxides. I'll send you a copy of the bar eval. | | With flux, there's a lot of good no-cleans out there that can handle most boards. There's a few that can handle the really tough boards. My approach on the flux is to figure out what's important - topside fillets, residues, solderballs, etc - for your application. For example, I couldn't tolerate tacky residues because some of my boards have keypad contacts. But the ability to foam the flux doesn't mean squat to me since I have sprayers. Set the criteria, bring the companies in for trials, and see what you like best. When you're settling on a flux, get the SIR numbers from the manufacturer. Many will just offer "pass" on their spec sheets. I don't like that; I want data to see by what margin the product passed. | | On paste, I think Phil Zarrow's method that Dave mentioned is the "27 board challenge" devised by AlphaMetals. It's basicaly a print-life and tack-life test that really pushes the pastes. Indium has a similar test. We used the 27-board challenge here when we qualified new paste last winter. The info should be available on Alpha's website. | | For hand solder, we were in the middle of qualifying new product when they announced that they were shutting our factory down, so we never finished it. We brought in about a half dozen manufacturers and put them to the test with our hand solderers. Of course everyone liked different products, but the predominant favorite among the real eaxperienced solderers was Aim, the majority of the other people liked the Alpha. | | I found that one of the most important parts of qualifying the new chemistries is getting the people involved. By getting the technicians and operators involved in the process, you get valuable input on things you might not notice, you get the buy-in from them when you change the process, they take more ownership, and you get a lot of help with a huge task. Then, the next time you update, you can call on the people who are already familiar with the qual process and it will go much more smoothly. | | Good luck! | | Chrys | | | | | | | | | | | |

reply »

#11593

Re: Setting up solder material evaluation (suggestions?) | 10 May, 1999

| | | | I am about to embark on an effort to evaluate 3 different solder material suppliers and their recommended materials for our assembly process, in an effort to find the best supplier/material. We do mixed technology, with NOCLEAN chemistry so I will be evaluating : | | | | | | | | 1. Liquid flux, for wavesolder (sprayed in some machines foamed in others) | | | | 2. solder paste for SMT assembly | | | | | | | | With the hope of having one supplier, and same chemistry throughout the line I will also be | | | | evaluating Roll Solder for handsoldering. | | | | | | | | If any of you have been through this type of an effort I would appreciate any information & suggestions you may have. | | | | | | | | � Existing papers/reports? | | | | � Material parameters measured? | | | | � How was the experiment set up? | | | | � Did supplier aid in the measurements? | | | | � Any other info. | | | | | | | | Thanks; | | | | | | | Kelly: | | | | | | 1 Other than it makes soldering materials sales people happy, there is no reason to buy all your soldering materials from one supplier. | | | 2 The following specifications are a good starting point for defining your soldering materials: | | | | | | ANSI/J-STD-004, Requirements for Soldering Fluxes | | | ANSI/J-STD-005, Requirements for Soldering Pastes | | | ANSI/J-STD-006, Requirements for Electronic Grade Solder Alloys and Fluxed and Non-Fluxed Solid Solders for Electronic Soldering Applications. You can buy them from a variety of locations including IPC. | | | | | | 3 Phil Zarro, ITM (someting or other) published a good "process document" for assessing solder pastes in a trade journal recently. You might be able to find it at his site or email him from his site and ask him for a reference or a copy. | | | | | | Good luck | | | | | | Dave F | | | | | | | | Hi Kelly, | | | | Qualifying new process chemistries is a pain in the butt, but a real good thing to do. | | | | When it comes to bar solder, the IPC spec is pretty broad. Most manufacturers have several grades of bar solder: stuff that meets IPC, stuff that's slightly better, and high purity stuff for tight-process window wave soldering or hot air levelling. And the spec does not address dross inclusion in the bar. Yep, that's right - bar solder comes with dross already in it, so as soon as it melts it floats to the top of the pot and you skim it off. There's a dross inclusion test you can perform to evaluate dross inclusion. When I did it, I found some sizable chunks of crap (3-5mm) in solder that was suppoed to be very pure, in addition to powdery oxides. I'll send you a copy of the bar eval. | | | | With flux, there's a lot of good no-cleans out there that can handle most boards. There's a few that can handle the really tough boards. My approach on the flux is to figure out what's important - topside fillets, residues, solderballs, etc - for your application. For example, I couldn't tolerate tacky residues because some of my boards have keypad contacts. But the ability to foam the flux doesn't mean squat to me since I have sprayers. Set the criteria, bring the companies in for trials, and see what you like best. When you're settling on a flux, get the SIR numbers from the manufacturer. Many will just offer "pass" on their spec sheets. I don't like that; I want data to see by what margin the product passed. | | | | On paste, I think Phil Zarrow's method that Dave mentioned is the "27 board challenge" devised by AlphaMetals. It's basicaly a print-life and tack-life test that really pushes the pastes. Indium has a similar test. We used the 27-board challenge here when we qualified new paste last winter. The info should be available on Alpha's website. | | | | For hand solder, we were in the middle of qualifying new product when they announced that they were shutting our factory down, so we never finished it. We brought in about a half dozen manufacturers and put them to the test with our hand solderers. Of course everyone liked different products, but the predominant favorite among the real eaxperienced solderers was Aim, the majority of the other people liked the Alpha. | | | | I found that one of the most important parts of qualifying the new chemistries is getting the people involved. By getting the technicians and operators involved in the process, you get valuable input on things you might not notice, you get the buy-in from them when you change the process, they take more ownership, and you get a lot of help with a huge task. Then, the next time you update, you can call on the people who are already familiar with the qual process and it will go much more smoothly. | | | | Good luck! | | | | Chrys | | | |Hi Kelly, This months (May'99) issue of Circuits Assembly has an article on benchmarking no clean solder paste and there are some valuable considerations. Tim O'Neill AIM Inc. | | | | | | | | | | | | | | | | | | | | | |

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