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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Humiseal 1A33 conformal coating using automated atomized spray

Jul 3, 2018 | Aquanox A4241 liquid to clean flux residues and using Oxygen only plasma to deal with surface energy issues. Visibly, we don't see flux residue under the microscope. Should we consider using other gases that would affect the contact angle of metal surfaces (Maybe, argon????) Are there any detrimental effect of oxygen-based plasma cleaning on metallic surfaces. The material that we are utilizing for this purpose is Humiseal 1A33 Urethane based conformal coating compound mixed with the recommended thinner in a ratio of 1:4 (as supported by the material TDS). Should we consider increasing viscosity

Testing effect of non-clean flux residue on solder joints

Nov 3, 2017 | Testing effect of non-clean flux residue on solder joints is ionic and still needs to be cleaned * IPA and empty containers are a hazardous material by RCRA criteria (40CFR 261) * Fire hazard with a flash point (~12*C TCC) * IPA is a volatile organic compound (VOC) at 1000 g/l * IPA is harmful to people, requiring personal protective equipment including

Acrylic Coating De-Wetting?

Jul 25, 2017 | process outline: - Wash (Aquastorm with chemistry, can't remember what we're using off the top of my head) - Bake (about 100c for a couple hours) - Plasma Clean (confirmed that adhesion is greatly increased, waiting for dyne pens to confirm, contact angles on DI water drops go from near 60 degrees , to almost nothing at all, so surface energy shouldn't be a problem) - Mask (ATS-667 tape for masking, known compatible with AR coatings, no silicone adhesives) - Plasma Clean again if too much time has passed during mask stage - Coat, 3 coats per side, resulting in 2-2.5 mil finished thickness as measured

White spots on PCBA after Selective Solder

Sep 11, 2015 | ) Changed the flux ----Current stop gap solution---- Cleaning with flux (surprisingly) and a subsequent DI wash process seems to make the white spots go away. We're hunting for the cause and fix it so that we don't spend extra time trying to hand clean the spots.

Universal GSM Feeder Issues

Aug 10, 2015 | -pins and the machine, but, most times, I am unable to get the feeder working. So far we have tried cleaning the contact areas on the machine, cleaning the contacts of the pogo-pins, as well as jiggling the feeder once installed to try to find a magic work point, all to no avail. Today, I'm having it at random spots

BGA epoxy removal

Feb 22, 2015 | Hi, my name is Dacian, and i run a mobile phone repair shop in Timisoara, Romania. Lately we decided to do more advance motherboard repair jobs, and a big problem that we have is, cleaning the board after we remove the chips. We repair manly iPhone, iPad and Samsung boards, and all of them have some kind of epoxy under the bigger BGA chips. The Apple ones have a black, type epoxy that when heated becomes kinda less hard but, almost every time we try to clean the space where the new chip will be mounted we damage some pads. Currently we are heating the spot to 200+ C and scraping with a sharp

SRX AUTOBAUD

Sep 25, 2013 | properly Measure line voltage & re-tap 2 Check Mod Codes MC’s 42, 43, 44, 45 3 X or Y Encoder defective Check the EEI & EHD board LED’s Clean & check glass scale 4 X or Y encoder cable defective Check the EEI & EHD board LED’s Clean and check glass scale 5 X, Y, Z motors defective Check & measure

DEK pro-flow

Feb 12, 2007 | : (Downloads can be found under Process -> Technical Papers) -ProFlow� upgrades (MPU's). -Paste Low Optimisation -Adjustment of the Print Carriage to ensure Squareness to the Stencil -Replacement of Hinge Pin Assembly -Conversion of ProFlow� to Horizontal Mount -ProFlow� Guides for Operators and Engineers solutions, including: The VectorGuard stencil system, Galaxy and Europa Micron-class printers for advanced SMT and semiconductor applications, RTC (Rapid Transit Conveyor) to enable a 4-second cycle time, Interactiv� machine support and ProFlow� DirEKt imaging for paste, adhesive PumpPrinting� and optimal lead-free printing. All of these latest innovations, as well as DEK�s full line of automatic and semi-automatic screen printers, sophisticated stencil technology and consumables will be on display. DEK is pleased to announce that both Cyclone and 3D Find-a-Part have been selected for submission

OSP Handling

Jun 27, 2003 | Since you�re asking the question about proper handling of OSP board, there may still be time to talk you out of using that material. * Cleaning of mis-printed board could cause non-wetting problems. This tends to remove a fraction of OSP coating. 0.35um thickness is indeed thin. * Training long. You might have problems if you run side A on Monday, side B on Tuesday, and wave them on Wednesday. Especially if you have additional processes, like a few water cleanings. * If you use alcohol to clean misprints from screen print or the SMT adhesive process, your WIP shelf life is reduced , OSP typically does not wet (accept solder) as well as some of the other finishes, and many folks have a tough transition over to no clean wave solder process with OSP products. Top side solder is a bit more difficult to achieve. So you may need to invest in a nice spray fluxer if you don't already

no contact on BGA

Jun 29, 2001 | Thanx for the reply guys!! The problem happened on only one PBGA, the balls are eutectic and the paste volume height is at 5.96 mil min. The stencil opening has been increased to 30 mil which initially was 20 mil. You guys are right!! One probable caused could be the warpage, of the PCB during

Non-Waveable SMT Caps

Jun 25, 2001 | Who is this, another Dave F ? For me there�s no problem with balling and beading. I know that the boards I have with the new paste do have all what�s needed for balling and beading, just one of the oldest designs with a stencil ...., oh boy, didn�t know that this thing was laying around here

0402 CHIP WITH GLUE PRINTING PROCESS

Jun 18, 2001 | HI ALL; I WOULD LIKE TO KNOW THAT ANYBODY CAN RUN GLUE PRINTING PROCESS WITH 0402 CHIP AND PASS THEM TO WAVE SOLDERING PROCESS ,PLEASE GIVE ME THE INFORMATION ABOUT THEM . 1)HOW WIDE OF APERTURE DO YOU OPEN ON YOUR STENCIL? 2)HOW MANY YIELD OF THIS PROCESS ESPACIALLY ABOUT DEFECT OF MISSING CHIP

Reflow Oven vs 0402 Tomb Stone

Jun 10, 2001 | Everybody aware of the tomb-stone problem on 0402 package. I've done everything I could i.e. Profile, placement, 10 Deg placement, stencil design, but still this culprit exist. One things for sure is taht I have a very bad pad size for 0402 ( 25 mil X 27 mil with the gap of 16 mil ), but before I

Solder Paste Volume

Apr 11, 2001 | pre-selected areas for stencil clogging, paste deposit area, registration, bridging, and does have sensitivity to the shape of the top of the deposit (it will reject an odd form top surface as long as it wasn't taught to accept it initially), I've decided NOT to measure paste height with my non

Reflow of 0402 capacitors

Mar 8, 2001 | different manufacturers with varying results but no solution, 5 mil stencil with 15% reduced aperture, checked pad/trace design for uneven wetting forces-some problem parts had ground planes on one side-but some did not, placement accuracy is not an issue-this problem only manifests itself on the 0402

Solder Balls

Feb 13, 2001 | to the chips and resistors. So we did across the board 10% aperture reduction on .006 stencils and got our printing aligned. Humidity plays havoc as well. Now in winter here in Chicago we have 0 balls but come summer be careful. I have tried 5 different pastes with Aim 293 showing the least balling, but your

converting from 0805's to smaller packages

Jan 8, 2001 | machines are a little short of maintenance you may then have some part skewing or shifting that may not effect the placement of 0603's but when you get to 0402's your margins for error are smaller. With 0402's, no matter what stencil design aperture you have, if the part is shifted over, it will tombstone.

Process Characterisation

Nov 30, 2000 | Michael, Thanks for your response. More info:- The processes are as follows, Stencil Print (6 thou on DEK 248) Placement on Contact 3AV and Reflow on BTU 4 zone Top & Bottom oven.It is not an In-Line system. Our board technology is mixed but heavily biased towards SMT double sided. The PTH

16 mil pitch QFP solder bridge

Oct 7, 2000 | is experiencing high defect rate. If there anyone helping me to clarify folowing: 1.How to identify short circuit is from substrate or assembly process. 2. What is reommended metal stencil design rule for fine pitch SMT. Any suggestion is hight appreciated. Regards,

Costing new products - Qty of solder paste

Aug 18, 2000 | Thanks Wolfgang / Charles Have tried method suggested by Wolfgang on one product, and seem to be a bit over (perhaps density calculation was a bit out). Also, the volume of paste deposited must be less than the voume of the apetures on the stencil because of paste adhering to the sides

LGA Stencil Spec

Aug 5, 2000 | Re: LGA Stencil Spec

Fine Pitch Components

Jul 24, 2000 | diameters, registration etc. You can also use them for aligning stencils very accurately! Buy one anyway, they are only about $100 max.

Dbl-Sided Reflow Question

Jun 2, 2000 | , and causes HASL "spikes." These HASL "spikes", in turn, screw up the screen printing for the 2nd side reflow because the spikes cause the stencil NOT to be flush to the board. Okay now here's the debate....my theory is that the HASL "bleeds out" of the VIA's because there is no flux in the VIA's - hence

DEK 265 opinions needed please

May 26, 2000 | tooling to the Formflex,Also they have a range of cameras for this series of machine ensure you choose the correct that will satisfy all your products and stencil types. Do not hesitate to contact me via email if you need further information. Sal.

Vias Under Discrete Components

Mar 15, 2000 | Armin: Locating vias within the courtyard of components is bad practice. Concerns are: * Poor solder paste print quality, caused by the via preventing good stencil gasketing. * Poor component reflow, caused by the via holding the component out of the paste. * Shorting between the component

BGA SOLDER BALL to SURFACE PAD size relationship

Feb 24, 2000 | . 4 With a 0.006 inch thick stencil, assuming you have 0.025 inch pitch or less components on your board as well as the BGA, the BGA aperture SB the same size and shape as the metal showing on the pad. Good luck and happy opinuating to all, Dave F

BGA SOLDER BALL to SURFACE PAD size relationship

Feb 24, 2000 | . 4 With a 0.006 inch thick stencil, assuming you have 0.025 inch pitch or less components on your board as well as the BGA, the BGA aperture SB the same size and shape as the metal showing on the pad. Good luck and happy opinuating to all, Dave F

ENIG finishing

Feb 15, 2000 | 100's at this pitch anywhere else, so I don't have another reference point. We do install one other 20mil part on another board, an soic, but don't have these solderability issues. Frankly, coplanarity is just one possibility that we're looking at. Paste, print quality/stencil design, profile, pad

Apply glue with a stainless stell stencil

Feb 13, 2000 | Re: Apply glue with a stainless stell stencil

Solder Beading under Cap...Need help

Feb 11, 2000 | the body of the component when it is placed. During reflow, the solder balls coalesce to form larger solder beads. These are usually located under or beside the component body. Options: Remake your stencil with "Home plate" appertures. This puts less volume of solder paste directly under the component

Mid Chip Solder Balls

Jan 14, 2000 | Dave: You're probably correct about too much paste, given that your balling is congrigated near the center of the chips. Three things to consider: 1 Lower temperature profile @ front 3 zones 2 I've heard some stencil suppliers can plate additional material to decrease the size of apertures

solder mask removal

Jan 5, 2000 | Several methods work well. 1. (Low Volume Method) Using an Xacto blade, scrape off the solder mask holding the blade flush being careful not to use the pointed part of the blade. 2. (High Volume Method)Tape off the area that you don't want the mask to be removed from, or make a stencil and sand

0201 Capacitor Solder Printing

Jan 3, 2000 | in the right direction. Another thing you can do is speak to your solder paste and stencil manufacturer they might have some info on this. Regards, Deon Nungaray SMT Mfg Engineer GMI USA

Buying stenciling and pick and place equipement.

Dec 18, 1999 | Re: Buying stenciling and pick and place equipement.

Buying stenciling and pick and place equipement.

Dec 18, 1999 | Re: Buying stenciling and pick and place equipement.

Screen Printer Visual Inspection Equipment

Dec 17, 1999 | Hi, C.K. Let's assume that your stencil's thickness is in a range 4-6 mil or by other words the height of the solder paste on a pads is the same (close enough to reality) Therefore, for pad's width more than 20 mils(as well as pitch between pads) the hight of solder paste can be neglectable

Double sided smt

Nov 1, 1999 | . Epoxy is only value-added if it prevents rework of your original process. Experiment with switching first pass and second pass sides (if permitted. If possible, change geometries of stencil to accomodate problematic parts. Run DOE on aperture dimensions and geometries. This has pulled my but outa

Aperture Reduction for QFP (fine pitch)

Sep 21, 1999 | the paste deposits. If anyone has tried anything along these lines, it would be good to hear about it. | | Scott | Scott: No reason not to try it. Also consider a "zipper pattern stencil." Aptly named, because the paste deposit looks like a zipper. To do this, make the apertures normal pad width

Metal Inspection Templates

Sep 21, 1999 | | | | I like to see if anyone has any info or experinces with metal inspection templates in a post oven process. | | | My problem issue is the ESD, since they are metal(12 mil stencil material). I welcome any comment. | | | | | | Thank you. | | | | | Just for ESD reasons if you have metallplates

Soldering to Gold

Sep 17, 1999 | fracture in service and some of these were in service for 15 years under fairly nasty climatic conditions. What I'm suggesting here is that cleaning + conformal coating MAY provide sufficient mechanical support to prevent them 'orrible intermetallics from causing cracking if you don't pre-tin but �m not buying "cleaning + conformal coating MAY provide sufficient mechanical support to prevent them 'orrible intermetallics." First, the intermetallics were formed "long" before the connection was cleaned or coated. They are formed during the soldering process and continue to form as long as the connection dangerous levels in my monthly solder pot analysis. While that�s probably true, but: � What about marginal soldering situations that occur before changing-out the solder pot? Because, (1) I�m not sure of the safety margin of gold concentration that�s acceptable before I should clean the pot (versus when

Tombstone

Sep 14, 1999 | ends are touching the paste. Depending on your stencil apertures and pad specification you can have everthing running with good Cpk but the parts are not touching paste on one side.

0201 components

Sep 14, 1999 | that stayed together and could be effectively placed and reflowed, notwithstanding providing stencil apertures small enough on "normal" foils. I'm ready to go back to Ohmega Ply as "embedded" types after this question. Best wishes to you and your very small design efforts - not meant in any negative way

Product Segmentation in Pick Place Machines?

Sep 10, 1999 | Okay guys (and my fellow lady lurkers), I am trying to determine WHAT the segmentation is for the products in the pick and place industry. For example, I know in screen/stencil printing, there are manuals, there are semi-automatics, mid- and high-range automatics. In p&p, however, I'm clueless

Product Segmentation in Pick Place Machines?

Sep 10, 1999 | Okay guys (and my fellow lady lurkers), I am trying to determine WHAT the segmentation is for the products in the pick and place industry. For example, I know in screen/stencil printing, there are manuals, there are semi-automatics, mid- and high-range automatics. In p&p, however, I'm clueless

SPOT (Solder Paste On Thru-Hole)

Aug 30, 1999 | | | Planning to evaluate the above process... | | Can anyone can give me some tips/infos on the above.... | | e.g. stencil aperture design, aperture ratio, common problems and solutions they encountered on the above process, is the profile different from an ordinary SMT process

SPOT (Solder Paste On Thru-Hole)

Aug 30, 1999 | | Planning to evaluate the above process... | Can anyone can give me some tips/infos on the above.... | e.g. stencil aperture design, aperture ratio, common problems and solutions they encountered on the above process, is the profile different from an ordinary SMT process....etc... | | All

Cylindrical diodes Missing during SMT process.

Aug 26, 1999 | | | | | | | | Hello everyone, | | | | | | | We found many cylindrical diodes missing during SMT process. Could someone tell us how to prevent this problem? Is it effective to change the shape of stencil apture or reduce fan speed in reflow oven? Thanks in advance

Tooling pins

Aug 24, 1999 | | Peter These thing are basically drafting and graphic arts registration pins. They are very useful. Two sources: Elite circuit equipment (manual stencil printer mfg.) in Garden Grove, Ca. 714/895-1911 (heard rumors about a new area code) Start International (production supplies distributor

Help for CSP Prototyping

Aug 21, 1999 | wasn't too bad, but .8's pushed the micro-stencil solder paste application process so we're working on that to improve yields. Just a note: I'm using the definition of CSP as being a "BGA" package not exceeding 20% of the chip size it encases. Earl Moon

20 mil qfp bridging

Aug 17, 1999 | nothing, verify everything. Hope this helps. Steve A | Hello | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | 100 durometer blade. Getting "tails

Defluxing Advanced Packages

PCB Soldering Tools