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Cleaning under, around, and through tight spaces

Earl Moon

#13106

Cleaning under, around, and through tight spaces | 5 January, 1999

A question for you all!

Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't.

My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them.

Thanks,

Earl Moon

reply »

Steve Gregory

#13107

Re: Cleaning under, around, and through tight spaces | 5 January, 1999

| A question for you all! | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them. | | Thanks, | | Earl Moon

Hey Moon-Man!

I'm b-a-a-c-k! Yeah, I hear ya'! I 'member back when we were looking at getting our aqueous cleaner when we were phasing out our trusty ol' Detrex Freon cleaner (just after we finished installing $10,000 worth of additional secondary cooling coils to bring it up to the Bay Area Air Quality Management Districts B.A.C.T. (best available control technology) retrofits to reduce emmissions, I remember it was a real serious deal to make sure we got a cleaner that we wouldn't have to sweat whether or not it would clean good. I was mostly an observer back then, not really involved in the decision making process on which brand of dishwasher we should buy...I was pretty new back then, still a little too wet behind the ears to know anything. (Get it? Wet behind the ears? Cleaners? HAR! HAR! I slay myself sometimes!)

But I do remember my manager Mike Briskey setting down with one of the other engineers to give him a final briefing before he went off on his mission to evaluate what cleaner we was gonna buy. Oh, he was prepared too! Had a glass plate with glass slugs glued on to it at different stand-off heights, with his little bottle of red colored flux so that he could squirt it all under the glass slugs, bake it in the reflow oven and then see how much each cleaner could wash off. We were paranoid, no doubt about it! And that was back when 25-mil was fairly new, and 20-mil pitch parts were just on the horizon (OH MY GAWD, how in the world were we EVER gonna clean underneath those!?!)

You know, you bring up a good question...I've never thought about it much until you brought it up. So, I did a little checking today, and talked with a few people who live and breath cleaners that's been around since those days when we were so paranoid.

It turns out that there was a good reason for concern back then with aqueous cleaners. Using water to clean flux residues was something new, and the industry was making cleaners that didn't have much balls...no, I don't mean the balls you play with...But the kind of balls that mean MO' POWER!! If you think back of some of the older water cleaners, how many nozzles would you typically see on a manifold? A lot of times I remember seeing three, one at each edge of the conveyer belt, and one at the center...and at least one of those was always plugged with a defect arrow or something. You look at the cleaners that's out there now, and you'll see at least 4, sometimes 5,6, or more on each manifold. The pumps have been taking steroids too...for instance the Trek Triton we have has 10-hp wash and rinse pumps, and dual 15-hp blowers...you'd never see that kind of horsepower in cleaners back then.

So that's what I gathered from talking with few "experts" who have been in the PCB cleaning business for a while. Basically the concern back then was a very valid one because there were so many crappy, under-powered cleaners on the market. We went from a cleaning technology that was mostly chemical in nature, to one that depends mostly on, and greatly affected by the mechanical forces, or impingement forces involved in spraying water. By the way, I was also told that the next biggest thing that has the greatest affect on cleaning results is water temperature...hot always cleans better than cold.

C-ya L8'er!

-Steve "clean ears" Gregory-

reply »

Earl Moon

#13108

Re: Cleaning under, around, and through tight spaces | 6 January, 1999

| | A question for you all! | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them. | | | | Thanks, | | | | Earl Moon | | Hey Moon-Man! | | I'm b-a-a-c-k! Yeah, I hear ya'! I 'member back when we were looking at getting our aqueous cleaner when we were phasing out our trusty ol' Detrex Freon cleaner (just after we finished installing $10,000 worth of additional secondary cooling coils to bring it up to the Bay Area Air Quality Management Districts B.A.C.T. (best available control technology) retrofits to reduce emmissions, I remember it was a real serious deal to make sure we got a cleaner that we wouldn't have to sweat whether or not it would clean good. I was mostly an observer back then, not really involved in the decision making process on which brand of dishwasher we should buy...I was pretty new back then, still a little too wet behind the ears to know anything. (Get it? Wet behind the ears? Cleaners? HAR! HAR! I slay myself sometimes!) | | But I do remember my manager Mike Briskey setting down with one of the other engineers to give him a final briefing before he went off on his mission to evaluate what cleaner we was gonna buy. Oh, he was prepared too! Had a glass plate with glass slugs glued on to it at different stand-off heights, with his little bottle of red colored flux so that he could squirt it all under the glass slugs, bake it in the reflow oven and then see how much each cleaner could wash off. We were paranoid, no doubt about it! And that was back when 25-mil was fairly new, and 20-mil pitch parts were just on the horizon (OH MY GAWD, how in the world were we EVER gonna clean underneath those!?!) | | You know, you bring up a good question...I've never thought about it much until you brought it up. So, I did a little checking today, and talked with a few people who live and breath cleaners that's been around since those days when we were so paranoid. | | It turns out that there was a good reason for concern back then with aqueous cleaners. Using water to clean flux residues was something new, and the industry was making cleaners that didn't have much balls...no, I don't mean the balls you play with...But the kind of balls that mean MO' POWER!! If you think back of some of the older water cleaners, how many nozzles would you typically see on a manifold? A lot of times I remember seeing three, one at each edge of the conveyer belt, and one at the center...and at least one of those was always plugged with a defect arrow or something. You look at the cleaners that's out there now, and you'll see at least 4, sometimes 5,6, or more on each manifold. The pumps have been taking steroids too...for instance the Trek Triton we have has 10-hp wash and rinse pumps, and dual 15-hp blowers...you'd never see that kind of horsepower in cleaners back then. | | So that's what I gathered from talking with few "experts" who have been in the PCB cleaning business for a while. Basically the concern back then was a very valid one because there were so many crappy, under-powered cleaners on the market. We went from a cleaning technology that was mostly chemical in nature, to one that depends mostly on, and greatly affected by the mechanical forces, or impingement forces involved in spraying water. By the way, I was also told that the next biggest thing that has the greatest affect on cleaning results is water temperature...hot always cleans better than cold. | | C-ya L8'er! | | -Steve "clean ears" Gregory- | | | | "Clean ears?" Damn steve, you spend way more time with this stuff than anyone should. But, that's why you know your stuff.

Playing with my balls? Another issue entirely, but very serious play when associated parts come into the game.

Yeah, in 1985 we started playing with this stuff when resin/rosin based fluxes were it and CFC's were dying rapidly. Hell, even fab shops said 25 mil pitch boards couldn't be made. It was a great time to look forward especially as everyone had their solder paste formulation (I even made my own) and the paste Phd's wouldn't talk to the the cleaning Phd's so we could really clean up their mess.

In 1987, or there abouts, we retro'd a cleaning machine (don't recall the brand) with high pressure nozzles, and lots of them, to the extent 400-800 psi was possible. Should have seen the lost and forgotten components at the bottom of the sumps when cleaned - a real master blaster.

Mike Brisky? A legend in his time and mind, as his wife once said at a Silicon Gulch SMTA "meating." He started a consultants revolution. Where is he now?

Glad I could draw you out from the IPC side of things, if but for a moment. Your graphic tells the story, but I, as you, am still concerned about how clean, clean is. I guess water molecules have gotten smaller with pressure and amount thrown at the problem - pardon me, I mean issue as there are no problems.

Earl Moon

reply »

Wayne Bracy

#13109

Re: Cleaning under, around, and through tight spaces | 6 January, 1999

Hi Steve:

Nice response, and most importantly, glad to see you back around.

wayne

reply »

Chrys

#13110

Re: Cleaning under, around, and through tight spaces | 6 January, 1999

| | A question for you all! | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them. | | | | Thanks, | | | | Earl Moon | | Hey Moon-Man! | | I'm b-a-a-c-k! Yeah, I hear ya'! I 'member back when we were looking at getting our aqueous cleaner when we were phasing out our trusty ol' Detrex Freon cleaner (just after we finished installing $10,000 worth of additional secondary cooling coils to bring it up to the Bay Area Air Quality Management Districts B.A.C.T. (best available control technology) retrofits to reduce emmissions, I remember it was a real serious deal to make sure we got a cleaner that we wouldn't have to sweat whether or not it would clean good. I was mostly an observer back then, not really involved in the decision making process on which brand of dishwasher we should buy...I was pretty new back then, still a little too wet behind the ears to know anything. (Get it? Wet behind the ears? Cleaners? HAR! HAR! I slay myself sometimes!) | | But I do remember my manager Mike Briskey setting down with one of the other engineers to give him a final briefing before he went off on his mission to evaluate what cleaner we was gonna buy. Oh, he was prepared too! Had a glass plate with glass slugs glued on to it at different stand-off heights, with his little bottle of red colored flux so that he could squirt it all under the glass slugs, bake it in the reflow oven and then see how much each cleaner could wash off. We were paranoid, no doubt about it! And that was back when 25-mil was fairly new, and 20-mil pitch parts were just on the horizon (OH MY GAWD, how in the world were we EVER gonna clean underneath those!?!) | | You know, you bring up a good question...I've never thought about it much until you brought it up. So, I did a little checking today, and talked with a few people who live and breath cleaners that's been around since those days when we were so paranoid. | | It turns out that there was a good reason for concern back then with aqueous cleaners. Using water to clean flux residues was something new, and the industry was making cleaners that didn't have much balls...no, I don't mean the balls you play with...But the kind of balls that mean MO' POWER!! If you think back of some of the older water cleaners, how many nozzles would you typically see on a manifold? A lot of times I remember seeing three, one at each edge of the conveyer belt, and one at the center...and at least one of those was always plugged with a defect arrow or something. You look at the cleaners that's out there now, and you'll see at least 4, sometimes 5,6, or more on each manifold. The pumps have been taking steroids too...for instance the Trek Triton we have has 10-hp wash and rinse pumps, and dual 15-hp blowers...you'd never see that kind of horsepower in cleaners back then. | | So that's what I gathered from talking with few "experts" who have been in the PCB cleaning business for a while. Basically the concern back then was a very valid one because there were so many crappy, under-powered cleaners on the market. We went from a cleaning technology that was mostly chemical in nature, to one that depends mostly on, and greatly affected by the mechanical forces, or impingement forces involved in spraying water. By the way, I was also told that the next biggest thing that has the greatest affect on cleaning results is water temperature...hot always cleans better than cold. | | C-ya L8'er! | | -Steve "clean ears" Gregory- | | | | Steve,

So good to see you back, old boy! Where ya been????

Chrys

reply »

Steve Gregory

#13111

Re: Cleaning under, around, and through tight spaces | 6 January, 1999

| Steve, | | So good to see you back, old boy! Where ya been???? | | Chrys

Hi ya' Chrys!

Oh, I've been around...just haven't had a whole lot of time like I used to. The place I'm working at now is a start-up (as you may know, I think I mentioned that before), and you know how things can go at start-ups...it's actually starting to wear me down some now. Being the only engineer here (well, the only one that doesn't mind getting a little flux and grease on his hands) I seem to never have enough hours in the day to do everything that has to get done. I don't have no maintenance person here, so on top of everything else I maintain everything too. Plus all the jobs we've been getting have been the pain-in-the-butt jobs that nobody else wants to bother with...1-10 boards with a lot of the SMT parts in strips and baggies, you know the "fun" stuff...it's getting old though...been like this for the last 3-months...I really don't want to do this much longer, and I've let the people here know that too...I feel I'm being wasted here.

Enough of that crap, I'm bumming myself out. Anyhoo, I'm back and I won't split for as long as I did before without asking permission...(GRIN)

C-ya L8'er!!

-Steve Gregory-

reply »

Kevin Ham

#13112

Re: Cleaning under, around, and through tight spaces | 12 October, 1999

| | A question for you all! | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them. | | | | Thanks, | | | | Earl Moon | | Hey Moon-Man! | | I'm b-a-a-c-k! Yeah, I hear ya'! I 'member back when we were looking at getting our aqueous cleaner when we were phasing out our trusty ol' Detrex Freon cleaner (just after we finished installing $10,000 worth of additional secondary cooling coils to bring it up to the Bay Area Air Quality Management Districts B.A.C.T. (best available control technology) retrofits to reduce emmissions, I remember it was a real serious deal to make sure we got a cleaner that we wouldn't have to sweat whether or not it would clean good. I was mostly an observer back then, not really involved in the decision making process on which brand of dishwasher we should buy...I was pretty new back then, still a little too wet behind the ears to know anything. (Get it? Wet behind the ears? Cleaners? HAR! HAR! I slay myself sometimes!) | | But I do remember my manager Mike Briskey setting down with one of the other engineers to give him a final briefing before he went off on his mission to evaluate what cleaner we was gonna buy. Oh, he was prepared too! Had a glass plate with glass slugs glued on to it at different stand-off heights, with his little bottle of red colored flux so that he could squirt it all under the glass slugs, bake it in the reflow oven and then see how much each cleaner could wash off. We were paranoid, no doubt about it! And that was back when 25-mil was fairly new, and 20-mil pitch parts were just on the horizon (OH MY GAWD, how in the world were we EVER gonna clean underneath those!?!) | | You know, you bring up a good question...I've never thought about it much until you brought it up. So, I did a little checking today, and talked with a few people who live and breath cleaners that's been around since those days when we were so paranoid. | | It turns out that there was a good reason for concern back then with aqueous cleaners. Using water to clean flux residues was something new, and the industry was making cleaners that didn't have much balls...no, I don't mean the balls you play with...But the kind of balls that mean MO' POWER!! If you think back of some of the older water cleaners, how many nozzles would you typically see on a manifold? A lot of times I remember seeing three, one at each edge of the conveyer belt, and one at the center...and at least one of those was always plugged with a defect arrow or something. You look at the cleaners that's out there now, and you'll see at least 4, sometimes 5,6, or more on each manifold. The pumps have been taking steroids too...for instance the Trek Triton we have has 10-hp wash and rinse pumps, and dual 15-hp blowers...you'd never see that kind of horsepower in cleaners back then. | | So that's what I gathered from talking with few "experts" who have been in the PCB cleaning business for a while. Basically the concern back then was a very valid one because there were so many crappy, under-powered cleaners on the market. We went from a cleaning technology that was mostly chemical in nature, to one that depends mostly on, and greatly affected by the mechanical forces, or impingement forces involved in spraying water. By the way, I was also told that the next biggest thing that has the greatest affect on cleaning results is water temperature...hot always cleans better than cold. | | C-ya L8'er! | | -Steve "clean ears" Gregory- | | | |

Good to see you STEVE

Has anyone considered "ULTRASONICS"

reply »

Brian W.

#13113

Re: Cleaning under, around, and through tight spaces | 12 October, 1999

| | | A question for you all! | | | | | | Back in the good old days, we didn't always know how clean was clean. Much has changed. Much hasn't. | | | | | | My question concerns cleaning under, through, and around tight spaces. Way back when, we could not clean under 20 mil pitch QFP's because the water molecules (that was the reason often given) couldn't evacuate particulate material left under components. What's changed - especially concerning CSP's as uBGA's etc. with clearances under 10 mils under them. | | | | | | Thanks, | | | | | | Earl Moon | | | | Hey Moon-Man! | | | | I'm b-a-a-c-k! Yeah, I hear ya'! I 'member back when we were looking at getting our aqueous cleaner when we were phasing out our trusty ol' Detrex Freon cleaner (just after we finished installing $10,000 worth of additional secondary cooling coils to bring it up to the Bay Area Air Quality Management Districts B.A.C.T. (best available control technology) retrofits to reduce emmissions, I remember it was a real serious deal to make sure we got a cleaner that we wouldn't have to sweat whether or not it would clean good. I was mostly an observer back then, not really involved in the decision making process on which brand of dishwasher we should buy...I was pretty new back then, still a little too wet behind the ears to know anything. (Get it? Wet behind the ears? Cleaners? HAR! HAR! I slay myself sometimes!) | | | | But I do remember my manager Mike Briskey setting down with one of the other engineers to give him a final briefing before he went off on his mission to evaluate what cleaner we was gonna buy. Oh, he was prepared too! Had a glass plate with glass slugs glued on to it at different stand-off heights, with his little bottle of red colored flux so that he could squirt it all under the glass slugs, bake it in the reflow oven and then see how much each cleaner could wash off. We were paranoid, no doubt about it! And that was back when 25-mil was fairly new, and 20-mil pitch parts were just on the horizon (OH MY GAWD, how in the world were we EVER gonna clean underneath those!?!) | | | | You know, you bring up a good question...I've never thought about it much until you brought it up. So, I did a little checking today, and talked with a few people who live and breath cleaners that's been around since those days when we were so paranoid. | | | | It turns out that there was a good reason for concern back then with aqueous cleaners. Using water to clean flux residues was something new, and the industry was making cleaners that didn't have much balls...no, I don't mean the balls you play with...But the kind of balls that mean MO' POWER!! If you think back of some of the older water cleaners, how many nozzles would you typically see on a manifold? A lot of times I remember seeing three, one at each edge of the conveyer belt, and one at the center...and at least one of those was always plugged with a defect arrow or something. You look at the cleaners that's out there now, and you'll see at least 4, sometimes 5,6, or more on each manifold. The pumps have been taking steroids too...for instance the Trek Triton we have has 10-hp wash and rinse pumps, and dual 15-hp blowers...you'd never see that kind of horsepower in cleaners back then. | | | | So that's what I gathered from talking with few "experts" who have been in the PCB cleaning business for a while. Basically the concern back then was a very valid one because there were so many crappy, under-powered cleaners on the market. We went from a cleaning technology that was mostly chemical in nature, to one that depends mostly on, and greatly affected by the mechanical forces, or impingement forces involved in spraying water. By the way, I was also told that the next biggest thing that has the greatest affect on cleaning results is water temperature...hot always cleans better than cold. | | | | C-ya L8'er! | | | | -Steve "clean ears" Gregory- | | | | | | | | | "Clean ears?" Damn steve, you spend way more time with this stuff than anyone should. But, that's why you know your stuff. | | Playing with my balls? Another issue entirely, but very serious play when associated parts come into the game. | | Yeah, in 1985 we started playing with this stuff when resin/rosin based fluxes were it and CFC's were dying rapidly. Hell, even fab shops said 25 mil pitch boards couldn't be made. It was a great time to look forward especially as everyone had their solder paste formulation (I even made my own) and the paste Phd's wouldn't talk to the the cleaning Phd's so we could really clean up their mess. | | In 1987, or there abouts, we retro'd a cleaning machine (don't recall the brand) with high pressure nozzles, and lots of them, to the extent 400-800 psi was possible. Should have seen the lost and forgotten components at the bottom of the sumps when cleaned - a real master blaster. | | Mike Brisky? A legend in his time and mind, as his wife once said at a Silicon Gulch SMTA "meating." He started a consultants revolution. Where is he now? | | Glad I could draw you out from the IPC side of things, if but for a moment. Your graphic tells the story, but I, as you, am still concerned about how clean, clean is. I guess water molecules have gotten smaller with pressure and amount thrown at the problem - pardon me, I mean issue as there are no problems. | | Earl Moon | In a former incarnation, we used to use a small percentage of saponifier to help get into the tight spaces, usually between 2% and 10%.

Brian

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