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Jun 25, 2019 | Dear Everyone, I'm having problem. the Switch component drop after reflow. First, this component placed on top side and through Reflow. Next, the Bottom side is placed component and through reflow. After that, the switch drop and have a gap. We are using Vitronics Reflow, Pls see picture and help me solving this problem. https://ibb.co/Mky9czM (NG, after bottom side through Reflow) https://ibb.co/YyqCF78 (OK, after Top side through Reflow) Rg Sang
Jan 8, 2019 | Hi Steve, We did the below trials today. 1. Run the board in O2 environment. result : Yellowish appearance was observed. After DI water Cleaning : Still the yellow color is there. 2. Same board run secondary side. Result : First side board yellow color appears more. After DI cleaning : Yellow appearance was there in first side. Second side was ok. 3. The boards were run in N2 environment. Result : very minute discoloration . After DI water cleaning : Its acceptable. .. Conclusion : With N2 environment. The boards had very minute yellow appearance, which is accepted
Aug 10, 2018 | How to install FBGA ICs on both sides of Flex boards with no stiffeners ? Hi Thomas, Thank you for your advice. BTW, unfortunately, I received negative answer from the Fixture house same as below. =========== We have an issue here. Your board is too thin. It is fine to make the fixture for first side. But when you run the second side, you can not have full support because the fixture have to clear for the component on the other side. It is not feasible to make the fixture for this board. Sorry for the inconvenience. =========== Does anyone know the better Houses or other solutions ? Still I need advice from experienced people...
Mar 27, 2018 | Hello Diego, are the components missing on the first side or the second side. Like Mr. Evtimov said, you can check before the oven the pcbs's visually and see what happens after the oven. In this way you can see if it is the oven for sure. Then there are most likely 2 options - components from top side falling due to big temperature and thermal mass when producing bottom side or popcorn effect. If it is popcorn - sounds more like outgassing of moist pcbs. But in popcorn you can be lucky sometimes to see components all over the panel and boards. You can try also drying the panels if that is your
Jan 11, 2017 | First, why do you have paste on the opposite side of the component. I would recommend having it on the same side. Second, how thick is your stencil? Pin in paste requires thickness, to fill the whole barrel. Stencil should be really thick. Try to manually apply paste(if your stencil is 6mil think about 12mil aperture) on the component side, insert component and reflow.
Dec 19, 2016 | Hi anyone have recommended pcb manufacturer? I've used Seeedstudio Fusion PCB service https://www.seeedstudio.com/fusion_pcb.html for PCB prototype a few times. I was quite happy with them, they were cheap, of pretty good quality, and they came fast! They not only offer prototype pcb, pcb assembly but also pcb stenicl
Oct 11, 2016 | of blab in the SMTnet archives on glue testing, torque, shear, push, testing tools, different glues etc No shortage of opinions here. On your process flow: Last time [what was a long time ago] I did the the process that you're describing, it went: Top side SMT=> Reflow => Top side DIP => Bottom side glue => Bottom side SMT => Wave solder ... We couldn't keep the DIP clinch apparatus away from the bottom side SMT if we did the bottom side SMT prior to DIP.
Jun 2, 2016 | Thanks, I have managed to get a step further and now get the additional info on the error that it is node 1. All cables are connected, will double check the power but I believe it has power, I seem to be able to drive everything in diagnostics mode with it failing randomly which makes me think it
Apr 16, 2015 | I would like to know good ways to market for production projects. We have updated our two lines, and have almost double our manufacturing capabilities. We have tried Thomas.net and Kelly before and think it is over priced. Have already updated website and created social media pages. Again, any
Feb 12, 2015 | We have a board that has an RF shield on one side and ceramic capacitors on the other side. The side with the capacitors is reflowed first, then the other side is reflowed. We have been experiencing cracked capacitors in these boards. My guess is that somehow the RF shield is contracting at a
Dec 31, 2014 | If you suspect a short, check the resistance on a new board that hasn't been powered up. The data sheet should give you the junction resistances that you're looking for. Double check against a component not assembled on the board. If you measure a short, take the part out of the circuit
Oct 31, 2014 | problem cropped up. Stencil? Changed squeeges, recalibrated pressure, same paste, double vison alignment, grid locks checked. Bill
Jul 4, 2014 | hmm... the picture of the funnel didn't display very well because it's double spaced. Just out of curiosity I have to ask, does anyone even understand what I wrote? Does anyone know where on the internet I should actually post something like this?
Jun 12, 2014 | What you need here is a double print process. You should have 5mil stencil for SMT followed by a 10-15mil stencil for TH. I don't know what quantities you are running or do you have the capability to add another printer in the line, but that would be your best choice. These joints don't look good
Jun 3, 2014 | Reflow 2nd side on Vitronics Soltec XPM I don't think you decide that based on the oven. More important is what kind of parts you have on the board. If you have big heavy parts you should run them as second side.Of course you have the option to put glue under the suspicious part and run it as a first side.
Mar 20, 2014 | I tried to check for the emitter and the receiver and I notice that the receiver is screwed into the side of the head and not easily accessible so I decide not to mess with it. this is what I did. I activated all of the clutches for the spindles and rotated the z axis until they were all down in a position where I could see the side hole. then I positioned a flash light on one side and looked at the opposite side of the spindles and saw the light shine on my eye. I also saw that the beam of light is round and not obstructed.
Aug 20, 2013 | When bridging becomes an issue, I like short leads. Lead Free is where I see most bridging occur. Usually when lead length starts to approach lead spacing. As long as the lead is discernible in the joint, it's acceptable. If you are having trouble with something like a double row header
Jun 27, 2013 | I had a solder paste SAC305 T4, with flux loading of 11.5%. After retrieivng out from fridge(5deg) after 48hrs, the paste turn dry (like dry mud? and after double checking the flux loading it becomes 12.5%. Has anyone ever experience this or any opinons on this weird scenario.
Aug 25, 2012 | Thank you RLM I was beginning to suspect what you have said when I think it is what is called a "flow control valve connection" it goes into a double acting cylinder? it needs to screw into M5 (metric 5mm)thread, the connector on the plastic hose is M7 nut,
Feb 17, 2012 | is a bad idea. * X-Outs are randomly placed * Machines can't read X-Outs * X-Outs are on the second side as often as they're on the first side If you're going to allow X-Outs, you need to make your fabricators: * Mark [remove, tape over] the fiducials on both sides of the defective boards in the panel * Sort panels by front side or back side defects * Sort panels according to location of the defect on the panel side When assessing the costs of X-Out panels, it's easy to start counting at the placement machine. Don't forget to consider wasted solder paste when assessing the cost of X-out panels.
Jan 19, 2012 | Yup, that sounds right. I did try one with red on top on one side and white on top on the other side. Oops, blew a capacitor out of the back of the base. If anyone else Has these, here's how it goes to make them work: Top pin on both sides = +12V, middle two pins: 0V / Common bottom pin: +5V . You only need one side to be plugged in, and I believe they could be daisy-chained, assuming the wiring can support the current.
Nov 22, 2011 | Process ideas for adhesive on bottom side SMD's and wave solder I am looking for process suggestions. We want to use a pin transfer system to deposit adhesive to hold bottom side SMD's in place. We will place SMD's and through hole power parts on the top side and then run through a wave solder machine. Are there any processing tips and things to avoid?
Oct 1, 2011 | If they sold you the lens and refuse to support it I'd demand your money back. I'd never deal with
Jan 28, 2010 | Walid, I just learned today that our ONYX500 Production Cell demo unit machine is for sale. This is located in our Connecticut office. You can use Juki feeders and tips (we buy them from Fred) and have a >9 micron placement accuracy. Includes Flipper unit, dispenser and double nozzle changer. Any
Dec 24, 2009 | GSM without side conveyors Get two connectors to fit the SMEMA 1 connectors on either end of the machine. Need only two wires on each connector going to momentary contact sw. Input is pins 1 & 2 to switch and output side is pins 3 & 4 to switch. If this doesn't work then change the connectors to the opposite sides. Let
Nov 13, 2009 | Hi dave, Sorry to hi-jack the tread a bit, but,we are experiencing some problems with components falling off somewhere in our factory, you made me think about printer settings being an issue. By print print, do you mean a double sweep of the squeegees, let them move to the front and to the back
May 20, 2009 | I have attached a pdf showing the dimensions for the QFN we placed. First, The pins on the part are not only on the bottom side but also wrap around to come up each of the 4 sides of the part as shown in the side view in the attached pdf. This is simailar to a castellated termination which is covered by IPC-A-610 section 8.2.4 (January 2000). Second, the assemblies passed full electrical test. We did not use X-ray inspection on the QFNs so a void on the bottom side is a possibility. However, based on the 2 inspection/test criteria listed above I am claiming 0 defects.
May 11, 2009 | What is the purpose of glueing it? If it is glue the bottom side parts followed by reflowing the top side parts followed by wave soldering the bottom side parts, then it's easy to measure. Hold the board with the 0603s facing down. If they don't fall off, it's strong enough. If you are doing
Aug 11, 2008 | What does your top side wetting look like? This is a perfect case where top side wetting will tell you when you have a good joint. Without seeingor knowing your process, I would suggest either more pre-heat or longer dwell in the solder. Either one should yield a better joint. But top side
May 17, 2008 | Jon, I tried to compile your code, but had to make 2 changes for happy compilation under Borland C++ Builder. Specifically: #include void outNum(double RealNum, long SigFrac) Now the question, could you post your component_file? Or was it generated by another piece of code? regards sarason
May 1, 2008 | We are having issues with these parts tilting to one side during reflow. Of course when they are tilted, they have to be reworked because the shield won't fit on. Changing board design and part design is not an option.... I think there are 2 reasons why they are tiliting: 1. The one side of the clip has a straight continuous edge across it, while the other side has a cut out in the middle. 2. The holes on the bottom of the clip have exposed copper on one side or the other sometimes. Has anyone ever encountered this ?
Dec 19, 2007 | Search the fine SMTnet Archives for previous discussion, like: Sep 7, 2007 | AOI side cameras Hello James. I've got a YesTech YTV-2050 system at work with one top-down camera, and 1 side-view camera for each of the four sides. I do have the side view cameras being used for automated side inspection. There are some parts with markings that are hard to read using the top-down camera , such as oscillators, and some plastic inductor packages. In addition, I also use the side view cameras to check lead solder banks for bridging/shorts on some of the fine pitch connectors where the legs point almost straight down towards the board.
Although, with some of the plastic inductor packages I mentioned
Sep 7, 2007 | AOI side cameras Hello James. I've got a YesTech YTV-2050 system at work with one top-down camera, and 1 side-view camera for each of the four sides. I do have the side view cameras being used for automated side inspection. There are some parts with markings that are hard to read using the top-down camera , such as oscillators, and some plastic inductor packages. In addition, I also use the side view cameras to check lead solder banks for bridging/shorts on some of the fine pitch connectors where the legs point almost straight down towards the board. Although, with some of the plastic inductor packages I mentioned
Aug 14, 2007 | > pick/place head won't travel over the LED's, then you won't be able to proceed. I wasn't clear in describing my board layout; It is LEDs on one side and SMT components on the other side. I don't think we can get around the problem of stenciling the SMT side after the LED leads are sticking
Apr 5, 2007 | not to flux the top side on those connector sites and see what you get. If the top side is preheated to the correct spec, then you should be getting hole fill. Your goal is to try to get as close to a zero delta between top side and bottom side board temp just prior to hitting the wave. I agree with Dave
Mar 26, 2007 | top side remelt? The temperature that will melt solder holding top side SMT components during wave soldering depends on the alloy of that solder. So, for example, you'd expect: * Near eutectic SnPb solder to melt around 215*C. * LF to melt around 240*C. It's common to see solder on top side components remelting near via, because via can act like heat pipes that conduct the heat of the wave solder pot to the top side of the board. If this is what you see, consider having the via pluged or caped. Covering the via with heat resistant tape works as a short term fix.
Mar 5, 2007 | I will have to rent a forklift to get it off the truck. If I don't cut the wall first, then the machine sits in the garage while the rental is ticking away at $200+ a day. Also, moving it twice doubles the possibility of a catastrophe. I've got some pretty good info now on the model, and it sure
Feb 20, 2007 | I am not familiar with the YV100XG pick & place but you might want to increase the mount height of these components The double stick tape isn't as thick solder paste. it might be pushing the component too far down causing it to twist. I encountered a similar problem with our topaz and a 976 Ball
Jan 18, 2007 | "solder tends to pool on the short side of the substrate" Does the short side of the substrate have any significant difference in thermal mass? if so, try slowing the belt (within reason) or increasing temps (within reason) to better equalize thermal distribution. maybe the sort side gets hotter
Sep 7, 2006 | normally one side is hydroentangled the other is not there is only one correct side which should be lint free and the other full of lint.that is wny people should never use rolls on both sides. Im of course talking typically (not sure of jnj brand) this is but can be seen easily under 60x mag
Aug 17, 2006 | I would imagine your system is either stainless and/or some form of plastic. The water can rust but I doubt your machine has any metal that would be affected by it. You may want to double check your spray cell as well. We have been running water soluble in our selective machine for years.
Aug 16, 2006 | I have seen a lot of discussion recently regarding reverse spike and double spikes in the reflow profiles of ovens. This is where a zone other then the last zone is the peak temperature, or where the last 2 zones have the same setpoint. Anyone have any experience with this and can talk about
Aug 7, 2006 | PCB type for BGA Dear Sir, To design PCB with 0.8mm pitch BGAs, is ENIG PCB is better than Tlectro-plating PCB? Why? Than, what is the most effective way to determine the connection between BGA and PCB is good and strong enough?
Mar 29, 2006 | You could alternatively look at it another way - the customer asked how quick it would be to change over 20-25 feeders. All of the above machines have the capacity to hold at least double this, so the question is can you run the orignal product, whilst at the same time adding the new feeders
Mar 26, 2006 | Would like to know if Fuji have made the CP7 0804P feeders in black body type. I currently purchased some 0804P feeders in black body type with the double safety lock. Someone said this is CP643 type. Not sure if this can be treated as CP7 feeders. If anyone knows, please advice. Thanks! Carl
Feb 28, 2006 | we use IFS, seems to be quite good,ive used several MRP systems and id say this is the best one ive used, one drawback is there are so many screens(100's) its difficult to remember which ones you need to use. from an engineers point of view i would recommend it. its also handy as it doubles as a
Jan 9, 2006 | When I had that luxury I always used a double pass, first wet then dry, to reduce the amount of wet solvent left on the stencil. That also gives it some time to evaporate. If you've got suction I don't know how you'd ever get any through the apertures unless you're really pouring it on.
Dec 25, 2005 | > Cheers for the info JAX, sounds like what I was > looking for. In the PTF You can have 2 matrix trays in the same feeder slot; one on the left side and one next to the other one; You don't need to mesaure the first pick-up location, distance from the right side. Opposite to the matrix tray on the left side. Wo said this will become easy? /
Dec 7, 2005 | You need a thicker mask/stencil, the openings should be .005" larger than ball diameter and the thickness should also be .005" thicker than the ball diameter. by making the mask thicker you can then just roll or scrape the extra balls off and any double stacks will show above the mask
Dec 4, 2005 | Not sure, but I would guess we used less than 100, 500 gram jars last year. Next year probably double or triple that. I think for the first 6 months of operation or so (before I started) they were pretty much using only samples. Nowhere near what a place like Celestica would use. But I"ve found
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