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

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


voc free flux

Glenn Peters

#12124

voc free flux | 28 March, 1999

I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. What disadvantages are there when using this flux? Do you have any contact details with any one using this type of application?

Regards,

Glenn

reply »

Vinesh Gandhi

#12125

Re: voc free flux | 29 March, 1999

Glenn,

i am aware of one unique problem with voc free fluxes. since these fluxes have certain amountb of water content they cause sputtering leading to solder balls & voids problems.

Regards

Vinesh Gandhi

| I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. | What disadvantages are there when using this flux? | Do you have any contact details with any one using this type of application? | | Regards, | | Glenn | |

reply »

#12126

Re: voc free flux | 29 March, 1999

| I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. | What disadvantages are there when using this flux? | Do you have any contact details with any one using this type of application? | | Regards, | | Glenn | | HI Glen,

Historically, VOC-free fluxes have not been as active as alcohol based or water solubles, and break down easier, requiring shorter wave contact times.

VOC-frees have come a long way in the past few years, however, and with nitrogen inerted waves, their performance is very, very good. Alpha is making them with greater thermal stability to last through longer contact periods (chip and laminar waves), Heraeus is making them very active for OSP's with almost no visible residue, and all companies are using better surfactants to break up bridges and solderballing.

The word of caution that Vinesh offered - make sure the flux is completely dried before it hits the wave to avoid solder splatters - is good advice. Another word of warning on this subject - if your solder mask isn't cured properly on your PWB, you porbably won't be able to get all the water vapor removed and you will see tons of micro-balling.

I know I promised my evaluation of VOC-frees would be ready by February, and I still haven't posted it yet, but please don't kill me. The internal copy is done, and all I have to do is go back and scrub the proprietary product names - I'm planning on it this week. I'll put up a posting when it's ready.

Chrys

reply »

George Steele

#12127

Re: voc free flux | 30 March, 1999

| | I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. | | What disadvantages are there when using this flux? | | Do you have any contact details with any one using this type of application? | | | | Regards, | | | | Glenn | | | | HI Glen, | | Historically, VOC-free fluxes have not been as active as alcohol based or water solubles, and break down easier, requiring shorter wave contact times. | | VOC-frees have come a long way in the past few years, however, and with nitrogen inerted waves, their performance is very, very good. Alpha is making them with greater thermal stability to last through longer contact periods (chip and laminar waves), Heraeus is making them very active for OSP's with almost no visible residue, and all companies are using better surfactants to break up bridges and solderballing. | | The word of caution that Vinesh offered - make sure the flux is completely dried before it hits the wave to avoid solder splatters - is good advice. Another word of warning on this subject - if your solder mask isn't cured properly on your PWB, you porbably won't be able to get all the water vapor removed and you will see tons of micro-balling. | | I know I promised my evaluation of VOC-frees would be ready by February, and I still haven't posted it yet, but please don't kill me. The internal copy is done, and all I have to do is go back and scrub the proprietary product names - I'm planning on it this week. I'll put up a posting when it's ready. | | Chrys |

I would like a copy of the evaluation too please. ty.

George Steele

reply »

Chris Kelly

#12128

Re: voc free flux | 1 April, 1999

Glenn,

There are both very good VOC-Free fluxes as well as alcohol based fluxes out there. This should be your primary focus if you are so lucky as to have to opportunity to actually select a flux!

The use of nitrogen will benefit any no-clean process in *varying degrees*. On the process side, you have to realize that N2 is just a band-aid to cover up a myriad process issues, ie., weak flux, oxidized boards, improper preheat profile, poorly appiled OSP coatings, etc., etc. I won't go into it but N2 also reduces dros to *varying degrees*. The variable of using N2 with either of these types of fluxes is not really important in regards to its effect on the soldering process. What I mean is...If you could hypotheticly have two *identical* fluxes, one being alcohol based and the other water based, I don't know of any reports showing that N2 will cause increased performance on one or the other type of flux, nor can I see any reason why it would. This is why I said, concentrate on finding the best performing flux for your process, whether it be VOC-free or not.

Like it has been mentioned already (get the hint?) if you do go with a water based flux, make REAL sure your machine or your process dries all of the water carrier from the PCB before going into the wave. This is best done with a convective style preheater but can be accomplished using IR heaters, albeit at a slower conveyor speed typically.

As for contacts of people using this type of setup...geez, there's countless numbers out there using VOC-Free flux and nitrogen combinations. It's definately not a new idea or something out of the ordinary.

I hope this answers your questions. Please feel more than free to contact me via email for any related issues.

Chris Kelly Product Specialist (Wave Solder) Speedline Technologies

| I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. | What disadvantages are there when using this flux? | Do you have any contact details with any one using this type of application? | | Regards, | | Glenn | |

reply »

ADRIANO FERNANDES

#12129

Re: voc free flux | 5 April, 1999

| | | I require some feed back from any one who knows about using a voc free flux in a nitrogen wave solder machine soldering both through hle and smt componants. | | | What disadvantages are there when using this flux? | | | Do you have any contact details with any one using this type of application? | | | | | | Regards, | | | | | | Glenn | | | | | | HI Glen, | | | | Historically, VOC-free fluxes have not been as active as alcohol based or water solubles, and break down easier, requiring shorter wave contact times. | | | | VOC-frees have come a long way in the past few years, however, and with nitrogen inerted waves, their performance is very, very good. Alpha is making them with greater thermal stability to last through longer contact periods (chip and laminar waves), Heraeus is making them very active for OSP's with almost no visible residue, and all companies are using better surfactants to break up bridges and solderballing. | | | | The word of caution that Vinesh offered - make sure the flux is completely dried before it hits the wave to avoid solder splatters - is good advice. Another word of warning on this subject - if your solder mask isn't cured properly on your PWB, you porbably won't be able to get all the water vapor removed and you will see tons of micro-balling. | | | | I know I promised my evaluation of VOC-frees would be ready by February, and I still haven't posted it yet, but please don't kill me. The internal copy is done, and all I have to do is go back and scrub the proprietary product names - I'm planning on it this week. I'll put up a posting when it's ready. | | | | Chrys | | | | | I would like a copy of the evaluation too please. ty. | | George Steele | chrys

I�d like to receive one copy about your VOC-FREE evaluation too

thank you

Adriano Fernandes

reply »

SMT Replacement Nozzles