Prove no-clean is clean

I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas?

reply »

| I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas? Wayne, Find out your customer's concern about the residue. Residue can be a pretty ambiguous term. Is their concern activity of the residue? Is it a future testibility concern? etc. If it's activity, put it through ionic contamination testing and show them there is nothing to worry about or subject the boards to some type of unfriendly environment. 85 degrees at 85% humidity for 4 weeks and check functionality / contamination afterwards. Also, find out what type of environment the product will be subjected to. That always helps. If the product is going to be subjected to the elements, I can understand their concern. Regards, Justin Medernach

reply »

| I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas? Justin's right - you need to find out why there is hesitation about residue. Right now I make a board that has contacts for a telephone keypad. One of the fluxes I've evaluated works great, but leaves a tacky reside. Yeah, this is a "safe" residue - non-insulative, low ionic contamination, yada yada yada, BUT in its application environment, dust and other particulates that are insulative can stick to the residue and a year from now the number 4 won't work on the keypad and everyone will say my phones are junk. The supplier is having a hard time understanding why I find the residue unaccpeptable when the solder quality is so remarkably stupendous. And perhaps I am going overboard with reliability concern, but its my product and I am responsible to make sure it works well for the next ten years. The moral of my story is that you need to address the specific concern, not the general "no-clean" issue.

reply »

| I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas? Wayne: More of the same as Chry and Justin. KEY ISSUE The first thing that you need to know is: What does your customer mean by clean? If your customer wants you to prove that your no-clean board is clean, what�s their spec? THE SPEC ANSI/J-STD-001B says that you can have up to 10.07 ugm/square inch of NaCl equivalent on the board and still be clean. That's not real clean. LT 6 ugm per square is cleaner. Some "high tech apps" require LT 2 ugm per square. TESTING METHOD A. Surface Insulation Resistance (SIR) testing tells you the amount of loading that your flux is putting on the assembly, but it won�t tell you what is on the surface. It (IPC-TM-650 method 2.6.3) is a common way to assess the functionality, contamination level, and reliability of a board. The process is real operator dependent. IPC-9201 discusses sources of variation and gives a better understanding of SIR testing. B. EMPF wrote a good paper on ionic contamination testing. Ionic contamination meters have been around for a long time. They measure only ionic contamination, not all the other "non-ionic good stuff" in no-cleans and water solubles. This is a very good process control tool, but most no-clean people don�t use ionic contamination testing, because: 1 They get terrible readings, mostly from relatively weak organic acids, instead of the halides and sulfate etc that they really want to measure. 2 Their boards end-up with ugly looking white solder connections, after soaking in 50/50 or 75/25 IPA/DI water. As Graham Naisbitt says: Ionic contamination testing is a cleaning process and no-clean means no-clean. (or words to that effect, sorry Graham) C. Ion chromatography tells you about all the stuff on the surface of your board, but doesn�t give an indication of reliability. For bare board analysis, ion chromatography (IPC-TM-650, method 2.3.28) is recommended. Only big shops maintain equipment for this. CSL, Trace, and Robisan are among the better test labs. COVER THE BASES As you push-on in understanding cleanliness (contamination) better, consider that the level of contamination on the assembly your customer receives is the result of all the processes at your: 1 Board fab house 2 Piece part suppliers 3 Own shop So when any of the processes at those places are changed, the contamination level on your finished product is potentially changed. Scary huh??? TTYL

reply »

| | I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas? | Wayne: More of the same as Chry and Justin. | KEY ISSUE | The first thing that you need to know is: What does your customer mean by clean? If your customer wants you to prove that your no-clean board is clean, what�s their spec? | THE SPEC | ANSI/J-STD-001B says that you can have up to 10.07 ugm/square inch of NaCl equivalent on the board and still be clean. That's not real clean. LT 6 ugm per square is cleaner. Some "high tech apps" require LT 2 ugm per square. | TESTING METHOD | A. Surface Insulation Resistance (SIR) testing tells you the amount of loading that your flux is putting on the assembly, but it won�t tell you what is on the surface. It (IPC-TM-650 method 2.6.3) is a common way to assess the functionality, contamination level, and reliability of a board. The process is real operator dependent. IPC-9201 discusses sources of variation and gives a better understanding of SIR testing. | B. EMPF wrote a good paper on ionic contamination testing. Ionic contamination meters have been around for a long time. They measure only ionic contamination, not all the other "non-ionic good stuff" in no-cleans and water solubles. This is a very good process control tool, but most no-clean people don�t use ionic contamination testing, because: | 1 They get terrible readings, mostly from relatively weak organic acids, instead of the halides and sulfate etc that they really want to measure. | 2 Their boards end-up with ugly looking white solder connections, after soaking in 50/50 or 75/25 IPA/DI water. As Graham Naisbitt says: Ionic contamination testing is a cleaning process and no-clean means no-clean. (or words to that effect, sorry Graham) | C. Ion chromatography tells you about all the stuff on the surface of your board, but doesn�t give an indication of reliability. For bare board analysis, ion chromatography (IPC-TM-650, method 2.3.28) is recommended. Only big shops maintain equipment for this. CSL, Trace, and Robisan are among the better test labs. | COVER THE BASES | As you push-on in understanding cleanliness (contamination) better, consider that the level of contamination on the assembly your customer receives is the result of all the processes at your: | 1 Board fab house | 2 Piece part suppliers | 3 Own shop | So when any of the processes at those places are changed, the contamination level on your finished product is potentially changed. Scary huh??? | TTYL Hi Dave I have a couple questions for ya 1) Have you memorized all of these IPC methods and Ansi specs or do you have to look them up every time? 2) Are you available as a human desk reference, if so I need your phone number. 3) What the H___ does TTYL Mean (Ta Ta ? ?)? Just wondering Mike

reply »

Wayne, I think Dave and Justin are correct but I would just add my twopennworth: Your customer presumably wants to know if the end-product will be reliable? If he/she wants you to prove cleanliness, ask them for the spec they want to work to and apply that to the contract. Bear in mind for your own info, that ionic testing to something less than 10mg per square, as stated by Dave, it also means that it is acceptable to leave UP TO that amount per square but if the end product is fine line/fine pitch and COB, BGA or other fancy devices, this level will almost certainly be too high. If the customer wishes to impose a penalty clause on you or an onerous warranty clause, then I recommend that, as suggested by Justin and Dave, you run SIR testing from J-STD-001 Appendix D and IPC-TM-650 but the condition is NOT 85/85. Dependant upon the Class of you product 1, 2 or 3 as defined within J-STD-001 is a condensing or non-condensing environment. Class 3 testing should be: 25 + 10 - 2 deg C to 65 +/- 2 degC, 90% to 98% RH, 6 2/3 cycling. Then you should take frequent readings of SIR - every 10 to 20 minutes because we have found dendrites within only 20 minutes. Further, you need to have these dendrites preserved so that you can analyse the cause using IC tests. If they ain't gonna impose a noxious warranty, run the Ionic test and the rest is their problem not yours! .....unless you care about the quality of your production? Regards Graham Naisbitt Graham.Naisbitt@concoat.co.uk | I need an evaluation process to prove to a customer that our no-clean process does not leave excessive residue? Any ideas?

reply »

Hey Mike: I�m glad we have the chance to get this out. 1) Have you memorized all of these IPC methods and ANSI specs or do you have to look them up every time? Yes and no. The stuff we use a lot, I�ve got memorized. Then there�s: A. Stuff we don�t use a lot, but I keep tripping over. B. Stuff that I can�t remember. C. Things that other people know that I don�t know, but may need to know. All this stuff (A, B, & C), my �Honey Do List,� my list of music that I need to find, books that I need to read, cigars that I hate, and more are on my Palm Pilot. 2) Are you available as a human desk reference, if so I need your phone number. I�ll tell you anything I know , but there are a lot of people that have forgotten more than I know. 3) What the H___ does TTYL Mean (Ta Ta ? ?)? TTYL -> Talk To You Later Ta Ta Ya La Dave F

reply »

| Hey Mike: I�m glad we have the chance to get this out. | 1) Have you memorized all of these IPC methods and ANSI specs | or do you have to look them up every time? | Yes and no. The stuff we use a lot, I�ve got memorized. Then there�s: | A. Stuff we don�t use a lot, but I keep tripping over. | B. Stuff that I can�t remember. | C. Things that other people know that I don�t know, but may need to know. | All this stuff (A, B, & C), my �Honey Do List,� my list of music that I need to find, books that I need to read, cigars that I hate, and more are on my Palm Pilot. | 2) Are you available as a human desk reference, if so I need your phone number. | I�ll tell you anything I know , but there are a lot of people that have forgotten more than I know. | 3) What the H___ does TTYL Mean (Ta Ta ? ?)? | TTYL -> Talk To You Later | Ta Ta Ya La | Dave F

I've even forgotten what I was going to say - but one thing I do remember is how valuable your ever present information is. This clean/no clean thing is getting more interesting every day. Where do you think we have to go, with what, and to what standard? I mean, as it is so often said, how clean is clean and what's the best way to measure it? Earl Moon

reply »

| | Hey Mike: I�m glad we have the chance to get this out. | | 1) Have you memorized all of these IPC methods and ANSI specs | | or do you have to look them up every time? | | Yes and no. The stuff we use a lot, I�ve got memorized. Then there�s: | | A. Stuff we don�t use a lot, but I keep tripping over. | | B. Stuff that I can�t remember. | | C. Things that other people know that I don�t know, but may need to know. | | All this stuff (A, B, & C), my �Honey Do List,� my list of music that I need to find, books that I need to read, cigars that I hate, and more are on my Palm Pilot. | | 2) Are you available as a human desk reference, if so I need your phone number. | | I�ll tell you anything I know , but there are a lot of people that have forgotten more than I know. | | 3) What the H___ does TTYL Mean (Ta Ta ? ?)? | | TTYL -> Talk To You Later | | Ta Ta Ya La | | Dave F | | I've even forgotten what I was going to say - but one thing I do remember is how valuable your ever present information is. | This clean/no clean thing is getting more interesting every day. Where do you think we have to go, with what, and to what standard? I mean, as it is so often said, how clean is clean and what's the best way to measure it? | Earl Moon Earl: It's Friday and I feel incinderary (what ever that means). Don't worry about that cleaning stuff. I think it�s all moot. In the next two years, the Brits and Continentals running the "Euro, ISO, IEC techno-lature" will ban products containing lead in another feeble attempt to protect: 1 Their decrepit socialist welfare states from global competition 2 The health of childern who eat televisions. So, rather than talking about dross and solder balls, then we can talk about bulk loading our magnaplanar framular VOC filters and epoxy balls. Have a nice weekend TTYL Dave F

reply »

| | | Hey Mike: I�m glad we have the chance to get this out. | | | 1) Have you memorized all of these IPC methods and ANSI specs | | | or do you have to look them up every time? | | | Yes and no. The stuff we use a lot, I�ve got memorized. Then there�s: | | | A. Stuff we don�t use a lot, but I keep tripping over. | | | B. Stuff that I can�t remember. | | | C. Things that other people know that I don�t know, but may need to know. | | | All this stuff (A, B, & C), my �Honey Do List,� my list of music that I need to find, books that I need to read, cigars that I hate, and more are on my Palm Pilot. | | | 2) Are you available as a human desk reference, if so I need your phone number. | | | I�ll tell you anything I know , but there are a lot of people that have forgotten more than I know. | | | 3) What the H___ does TTYL Mean (Ta Ta ? ?)? | | | TTYL -> Talk To You Later | | | Ta Ta Ya La | | | Dave F | | | | I've even forgotten what I was going to say - but one thing I do remember is how valuable your ever present information is. | | This clean/no clean thing is getting more interesting every day. Where do you think we have to go, with what, and to what standard? I mean, as it is so often said, how clean is clean and what's the best way to measure it? | | Earl Moon | Earl: It's Friday and I feel incinderary (what ever that means). | Don't worry about that cleaning stuff. I think it�s all moot. In the next two years, the Brits and Continentals running the "Euro, ISO, IEC techno-lature" will ban products containing lead in another feeble attempt to protect: | 1 Their decrepit socialist welfare states from global competition | 2 The health of childern who eat televisions. | So, rather than talking about dross and solder balls, then we can talk about bulk loading our magnaplanar framular VOC filters and epoxy balls. | Have a nice weekend | TTYL | Dave F Dave, Burn baby, burn. Hell, where I'll be hanging out no doubt, we'll be doing VOC free no clean to boot. Wasn't it you who posted the Japanese stuff talking lead free by 2001. And what about all the soldering we did with Indium on leadless devices to achieve "compliance." What does Indium do to children's minds? Mine is already lead saturated. Hmmm! Feels good. Moonman

reply »

On Friday, 18 September 1998, Moonman sayeth: What does Indium do to children's minds? Mine is already lead saturated. Hmmm! Feels good. Moonman Yo' Moon dude... I doesn't do a thing, and I know. I use ta' play cowboys and Indiums all the time, and I turned out normal...'cept that I drool a lot and I like to put coco puffs up my nose... -Steve Gregory-

reply »

| On Friday, 18 September 1998, Moonman sayeth: | What does Indium do to children's minds? Mine is already lead saturated. Hmmm! Feels good. | Moonman | Yo' Moon dude... | I doesn't do a thing, and I know. I use ta' play cowboys and Indiums all the time, and I turned out normal...'cept that I drool a lot and I like to put coco puffs up my nose... | -Steve Gregory- Only if you're an Indium. Besides, you (as most of us it is likely) love sniffing rare stuff (no, not like dogs but an interesting - forget it). Also, caught your act concerning "lickering up." Whoha nelly. Where in hell do you get graphics bigger than your message. Plus, revisit my question concerning cold, dead Seho solder pots on Technet. Give me the straight scoop straight arrow. I got lots of solder for sale or? Moonman

reply »