stencil cleaning

"stencil cleaning" search results in the Electronics Forums

9814 result s found for "stencil cleaning" in the Electronics Forums

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Starting new soldering process

Feb 21, 2017 | processes - currently looking at: Sparkle Flux SR-12 to be used with an AIM Sn100C solder 2) Looking for ocnsistent flux dispensing solutions; currently using the infamous flux bottles 3) Automated cleaning solutions post-soldering with multiple non-washable, unsealed components on PCBA; currently manually cleaning with a brush & wipes Currently looking at YesTech AOI and manual inspection methods for our IPC Class-3 products. Any tips on process development? FYI, the PCBs in question are about 10"x4". Thanks!

Conformal coat material dispensed through epoxy needle?

Feb 7, 2017 | to disassemble and clean it 3 or 4 times over 5 years. For cleaning I just let all parts soak in MEK over night, and then scrubbed/rinsed with MEK in the morning. The conditioner we use, (not sure if it'd work with conformal coat):

Wave soldering defects

Dec 30, 2016 | 't flash it off with extreme pre heat then it's not the flux. Is this happening on all your boards? If it's on an isolated assembly it could be uncured or contaminated solder mask. you said you cleaned the pot. The pictures show solder dross all over the board. It looks like you pumping dross. Did you empty the pot and pull the pumps and clean them? Last your solder could be contaminated. Send a sample off to your solder supplier for analysis.

63/37 HASL Finish / RoHS Solder Paste

Dec 11, 2016 | What type of flux is in your solder paste? Active or No-Clean? With lead free solder you really should be using an active flux. The lead free oxidizes during reflow if you are not using a Nitrogen or Vapor Phase reflow. So a more robust and active flux will help over come this with an open finish. If you desolder the BGA pads and look at them under high magnification. You may see speckled area's of copper where the solder will not wet. I think this is from the copper not being properly cleaned or possibly contaminated in the fab process. This will cause a void where the solder does

Amtech 4300 no-clean+washable flux

Dec 11, 2016 | Amtech 4300 no-clean+washable flux We have been using the Amtech line for over 12 years now with all of our PCB and BGA Rework. The NWS-4400 is mildly active and will give better results with Lead Free Solder. Note that the LF-4300 is considered a No-Clean. However it will show leakage at over 50 meg ohm measurements. So if you

DEK 03 - Consumable Replenish Error

Mar 25, 2016 | and replace the paper properly - it is very important for the paper, otherwise can give you errors like that. 2. Check your cleaning material weight sensor. 3. Check you paste dispenser and sensor to it (if you have this). For me, if it is stopping on cleaning it is either 1 or 2. You just have to replace

Tin Lead Solder Paste

Aug 12, 2015 | the Start-up Time again. We find a lead-free paste but our process is tin lead: I hope you can help me! We use SH6309-RMA solder paste: -Juan

Flux wave on PCBs

Mar 10, 2015 | Hi I have been struggling with boards for high quality picky customer. I am getting flux waves (like splashed - too hard to clean) after wave, where as we are still using Kester 979 (No clean flux, but as we are getting visible marks which looks similar like dross with flux. I have attached

Flux waves on PCBs

Mar 10, 2015 | Hi I have been struggling with boards for high quality picky customer. I am getting flux waves (like splashed - too hard to clean) after wave, where as we are still using Kester 979 (No clean flux, but as we are getting visible marks which looks similar like dross with flux. I have attached

Flux waves on PCBs

Mar 10, 2015 | Hi I have been struggling with boards for high quality picky customer. I am getting flux waves (like splashed - too hard to clean) after wave, where as we are still using Kester 979 (No clean flux, but as we are getting visible marks which looks similar like dross with flux. I have attached

High-speed solder paste dispensing. MY500, MY600, FX-D....?

Dec 30, 2014 | . - At the end of a workweek, the paste tube is removed, excess paste is drawn through the auger to clear the small transfer tube, and then the auger, needle, and tube are cleaned with isopropyl alcohol in an ultrasonic cleaner. They are also manually cleaned of any caked-on solder or leftovers in tight spots

MPM Accuflex fails to initialize powered rail

Jul 18, 2014 | cleans the lead screws, and lubricated them. I've lubricated the bushing for the idler pulleys, and finally replaced the very expensive drive motor. And it failed again this morning. I know the rails are square, the lead screws are clean, and the motor should be good. Idler pulleys are turning

unknown nozzle st 17

Nov 17, 2013 | Hi, I have difficulty on solving unknown nozzle st 17.situation goes like this,almost I run bout 6 models each day,but 1 to 2 models only have this problem.I almost done a few basic troubshoot such as clean censor st 17,clean cluch using proper material, and try to swap nozzle holder as well

nozzle cleaning GSM

May 17, 2013 | nozzle cleaning GSM , this will give you more access to the tip as well as allow you to thoroughy clean the screen.

ERSA Selective Solder questions

Apr 29, 2013 | should be 1mm below the top of the nozzle. If not change number and try again. We use 65% for the wave height and 60% when it does a test. For our 3/6 nozzle. Some larger nozzles are different. Adipic Acid and a stainless steal brush will help keep the nozzle clean. Also get a brush to go down inside the nozzle with also help. You should also get a long brush to go into the center of the pump when you clean the pot.

Selective solder machine leaving solder balles everywhere

Apr 5, 2013 | We have two ZipaTec 460s Selective Solder Machines, one for Lead and one for Lead-Free. This morning we noticed the solder pot was covered in solder balls, and after asking the operator what they had run, the answer was "Nothing." The operator had also cleaned the machine that morning. It had been about 2hr after she had cleaned it that it was noticed. This is on the Leaded Machine and after taking the pump out and inspecting it and checking the channel for issues that would maybe cause any form of issue, we had nothing. We can't figure out why solder is being splattered all over the machine

Conformal Coating Equipment

Feb 20, 2013 | where you put it more often. I've used PVA in the past, which was alright. But the best machine I've used was by far the Asymtek with the jet head. Also, if you're going to coat boards make sure you guys have a good way to get the boards clean, really clean, otherwise you'll just chase your tail

Soldermask - sulfur presence

Jun 25, 2012 | Our Customer had detected tarnished pad on ImAg PCBA and had conducted several SEM-EDX test at the soldermask below some of the chip resistors. High concentration of sulfur was found and it can be significantly reduced after further chemical cleaned - as verified again by SEM EDX. Our Customer requires us to wash clean the PCBA due to risk of metal migration should such 'free' sulfur being transferred onto the pads later which may induce creep corrosion. Need advises on: a) is there such thing as 'free' sulfur on top of the soldermask after it was cured by the PCB supplier? b) if these 'free

What is the best way to keep ESD totes clean?

Nov 18, 2011 | What is the best way to keep ESD totes clean? ). If you have no QC personal, make up a procedure on your own and meet with those responsible for the cleaning and let them know what is expected. If there is still no compliance...well, you have a disciplinary process don't you?

Using isopropanol with DI water for rinsing after washing boards

Nov 11, 2011 | On cleaning under low standoff components: How about reading the papers that Mike kindly posted for you above? It's intended to answer questions about cleaning under low standoff components. On conferences, exhibitions, and shows: The BIGGEST show on the planet is in Euroland

Selective Soldering

Oct 4, 2011 | Having a selective solder machine without a preheat sounds ODD. Preheats are pretty important to drive off flux volatiles and activate the flux so it cleans the parts ready for the solder to wet to them. If you have no preheat then you must be expecting the contact with the solder to do all your when the part goes into the solder ?Also, 857 is a very active alcohol based water wash flux...are you doing thorough cleaning after soldering to remove the active residues ?

Maintenance on a Trieber Wave Solder Machine

Oct 20, 2010 | " when we clean our solder pot in the mornings, It won't remove the dross, but it helps separate the good solder from the dross. Make sure you wear a mask and eye protection when cleaning the pot.

Dust Level of SMT Floor

Oct 12, 2010 | Obviously a totally clean floor is the best. So what if you have 1 particle of dust on your entire production floor? Is that 1 part per million (1 PPM)? or is that 1 part per billion? or 1 part per ???? How do you measure dust and come up with a PPM number? It also depends on what you are producing. If you are building medical or aerospace equipment you probably need to be in a class 10,000 (or better) clean room. If building consumer electronics, sweeping/moping the floor 2-3 times a week may be good enough. At my company, we concentrate more on keeping the benches/shelves/equipment dust

Batch cleaner

Sep 7, 2010 | them to perform cleaning evaluations. Insist that they record (video) the entire process and provide a detailed timeline. 2. Inspect the assemblies ionically (ROSE test) and visually. Request the cleaner's SPC data to review the specifics of each process step. The good news is that both batch and inline defluxing systems are capable of effectively removing all process residues, even in high density applications. The decision drivers that should determine batch or inline should be based solely on volume and economics, not cleaning performance. Mike Konrad Aqueous Technologies www

Unusual solderability issue

May 6, 2010 | tension and possibly allow for a more thorough cleaning. Just my thoughts though. We are considering removing the capping process to give the board shop a better chance of cleaning the vias properly as well. The saga continues. I'll update again as more events occur.

Unusual solderability issue

Apr 23, 2010 | Hi all, The board shop finally got back to me with some results. They did find residue present on some of the pads. They have sent a board out for evaluation to learn what it is. Hopefully from that we can determine the root cause. The good news is that they are able to clean the residue. We confirmed by running two boards through our print and reflow process without components. The first board was left as is and the second had been cleaned at the board shop. As you can see from the attached photo the contaminated board many pads did not solder. Again this only shows up on BGA pads

Bubbles on solder joint(after conformal coating curing)

Dec 18, 2009 | Tom: Once again - why are you using solvent based conformal coating. 1B31 is OK as a CC but it contains Toluene and MEK!! It is only 35% solids which means you are trying to get rid of 65% solvent. If you must use it due to customers requirement then be sure everything is absolutely clean and dry . Look at it this way. If you were painting your house would you put paint over loose material or dirty siding? Of course not. Using solvent based coatings means paying attention to details. Are you using "no clean" flux? If you are applying a coating over this look out for particles on the board

Chip Capacitor Uneven Surface

Sep 29, 2009 | Sean, Is this the only chip component that exhibits this condition? Only one location or only one part number? What are you using for chemistry? (OA, No Clean) if the parts do not look like this when they leave, I would send a sample of an unprocessed part, one that had been mounted and then one parameters that need to be looked at. Process temps, chemistry, cleaning, etc. This becomed more focused if the problem applies to one part, one location or all chip components. Please let us know how you are making out. Thanks Chris

Flux residue

Jul 31, 2009 | Dear Sean Contrary to believe MOST formulators of No Clean fluxes or No Residue fluxes use organic acides that are in fact weak and benign. IF the residue was left on the board and you had a condensing atmosphere then you may see some issue with falling SIR values, but generally not electromigration. UNLESS the resiue left was a Halide containing residue (not No Clean) then you may see electromigration or much poorer SIR values. So the residue appears some time after. Is the PCB visibly wet after wave? Do you see a waxy/greasy residue as it could be that we are seeing the porous resist

Baking assemblies after ultrasonic water wash

Jun 11, 2009 | Our cleaning process involves the assemblies being completely immersed in the water bath of the ultrasonic cleaner. The assembly has a QFP44 on it. Customer stated that when these assemblies have been cleaned with water in the past (at a different manufacturer) they had problems with water being

Clean vs No-Clean

Sep 10, 2008 | I guess sarcasm and quick wit flies over some peoples' heads. 8 years ago (wow, that's an old post)

no clean flux + wave soldering issue

Aug 28, 2008 | no clean flux + wave soldering issue ? Do you foam or what? Alot can be made from know ing info. Double check your settings between your boards too. You no the ones you say are bad and good. Cause sometimes it's morethat just your fluxer settting. You preheats and wave setting can make a board look clean or not. Make sure all you

Leaded and Lead-Free Wave Parameters

May 21, 2008 | Here's what I've seen for no-clean flux applications: Leaded: Dwell Time is? 2 - 3 seconds Top side board temp max? If some small SMT parts reflow are we too hot? 110 to 120C top side board temp just before hitting the wave(s) Pot temp. 245C Lead Free: Dwell time is? 4 to 6 seconds Top side board temp peak? 150 to 170C top side board temp just prior to hitting the wave(s) Water Based No-Clean fluxes have performed better from my experience- they can survive the elevated preheat temps better than IPA based. Pot temp. 262C

Tented Via's

Feb 22, 2008 | Are you using nocleans, especially when you get to SMT? Years ago, I had OA wave flux get into vias that were plugged from the top under parts. It is really difficult to clean small, high aspect ratio vias. Cross sections showed that the copper in the middle of the barrel was actually eaten away enough that it had fractured opening up the via. We talked the customer into going from 8 mil holes to 12 (saved them some fab money in the process), and got enough cleaning margin to make it work. You have to decide which side will get exposed to what, and work out the plug (there is no tenting

Micro Solder Balls in No Clean Selective Solder Process

Jan 8, 2008 | Micro Solder Balls in No Clean Selective Solder Process We are building class 3 products, using no clean on wave and selective solder machines. Both processes are producing micro solder balls between the leads of through hole components. I have searched the site and haven't found any recent threads on how people have been able to eliminate the issue

Stainless Steel tabs in brd assemblies

Jan 7, 2008 | if you don't use proper precautions. Secondly, the neutralization (water) can make the job worse if running no clean and no DI source. But if it's a battery bank (buncha D cells), like what the original poster mentioned, prolly good ol' baking soda and water with a clean water flush will work, followed

Fuji CP-6 Feeder Maintenance Programs

Oct 22, 2007 | with the mylar, especially on the 12x4 and 12x8 feeders. I am still not sure what is going on, but I am cleaning the tape leaf cover, changing the springs, and cleaning the O-ring in the take up wheel. I know most of these feeders have not been maintained in over a year, but I am 6 months new to being a feeder


Jun 13, 2007 | Most often, when people talk about a dishwasher, here on SMTnet, they're talking about a batch cleaner, not a dishwasher from Sears, or someplace like that. For limited applications, a home use dishwasher will do a perfectly adequate job of cleaning your boards. For more look here: There's lots of good reasons to use cleaning equipment designer for circuit boards. Here are some people to talk to: * Aqueous Technologies

SAC305 Water Soluble Pastes

Jun 5, 2007 | We just tested AMTECH's LF4300 with good results. Excellent reflow/profiling capabilities, good processing. And decent cleaning. I say decent cleaning, because we did run into a small issue. While using Qualitek's LF paste, we experienced a lot of "sudsing" in de-I wash. With the Amtech paste

Rosin vs. Resin Flux

May 31, 2007 | A solder wire classified as L0 under IPC J-STD-004 means that the flux residues can be left on the board safely, and when you select this type of cored wire the intention is not to clean. You just select a solder wire that gives you an acceptable level of flux residues depending on your company �s or customers criteria ( for cosmetic reasons only). RE or RO has nothing to do with performance or reliability of the flux it�s just an indicator for the flux main vehicle make-up. Just make sure you select an L0 solder wire with enough activity to do the job. Things usually go wrong in a no-clean

IEC 60601-1 Humidity Failures - No Clean Flux

May 7, 2007 | IEC 60601-1 Humidity Failures - No Clean Flux have either. Going to be checking this. Does anyone have experience with IEC 60601-1 testing using a Lead Free No Clean process?

Can someone help me on correcting CAD information on Univesal mc

Feb 1, 2007 | have said is ok for me . Another question, Is there any way to clean the nozzles of my GSM machines ( because sometimes the reject rate is too big ) and this is due to cleaning of the nozzles I think. a freind has told me to use Izopropyl Alcohol . but I do't know what is the adequate soluble to use

BGA rework with unplugged vias PCB

Dec 7, 2006 | As you are aware the common method to rework BGA is : 1. Remove BGA with hot air reflow machine ( SRT as current practice) 2. Clean the BGA pad using solder iron and solder wick. 3. Replace BGA with SRT rework machine. The problem we have with unplug via is when we clean the BGA pad

Flux residue cleaning procedure

Oct 31, 2006 | Flux residue cleaning procedure of the nearby BGA ... which is it? Next, the method for cleaning the white residue on the connector will depend on the composition of that material. You say that it is flux. What type of flux do you have on the connector? Finally, whenever we hear "white residue" and "flux" used in the same sentance, we

Forums a bit ugly

Sep 21, 2006 | Hi, I don't want to sound too negative here, because this forums been an incredibly help over the years, however does anyone else think it's a bit ugly. Perhaps it's just me, but it has not really changed over the years I have been using it, and it could be cleaned up a little, and be a bit guess its like asking your kids to clean up their rooms. You don't want to kick them out of the house, but would just like the environment a little nicer! Grant

Fibers In Solder Joints

Sep 6, 2006 | I don't remember ever having that problem with my EKRAs, but you might look at how much fluid you're dispensing on to the cleaning medium if this is occurring while you're using wet cleaning cycles. It could be getting saturated to the point of weakness. I also don't remember if there is a height

No clean with higher SIR values

Jun 13, 2006 | No clean with higher SIR values Wow, good luck. None of my test results would be helpful since we use IPC-B-24 test boards as received from our board suppliers so we have a clear understanding of what we're shipping customers, not necessarily paste performance alone. We'll only clean them prior to SIR if it's part of our

Lead free contamination at reflow

May 18, 2006 | increase. Width adjust mechanisms, etc.. Flux residues tend to "bake" on the system, more difficult to clean so to combat, more frequent cleanings. Internal temperatures of the blowers are higher, bearing life can be shortened. If you use N2 for lead free, seals will be a factor, higher temps dry them

CP6 Maintenance

Apr 17, 2006 | Okay, we got the machine back together about 2 weeks ago, cleaned the clutches and measured the placement accuracy. We are back up 100%, and have not seen any stn 17 & stn 19 nozzle errors. Thanks guys!! 19 of the 20 clutches are really tight; they don't move easily when turned. One of them however, is quite loose. I've re-cleaned it several times and it won't tighten up. I'm hoping it the bottom portion of the clutch (on the shaft) but have you ever heard of the top portion (attahed to the turret gear) wearing out? It's welded, or is a part of, the turret gear so It'd be pretty bad news

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