Electronics Forum | Thu Jun 13 09:39:43 EDT 2019 | don_julio
Problem is I don't have a mesh belt (lesson learned). Our conveyor is pins. If I laid some scrap pcb's spanning the conveyor pins on the long dimension of the board, I'm confident it would sag. We get a bit of sag today in our 1.6mm thick boards whi
Electronics Forum | Fri Feb 27 15:48:13 EST 2004 | pdeuel
Dose anybody know of a method of preventing board sag in the wave process. We have a 2 year old Deltawave. The product we are running is a one sided 10in x 12in panel of 6 PCB's. Pin headers and connectors are near all of the edges. Our current board
Electronics Forum | Wed Jan 29 08:32:48 EST 2020 | dontfeedphils
I'm currently running Grid-Lok in my printer and have used it almost exclusively in the past. That being said, I'm looking for a solution to help correct/remove sag and warpage on PCBs that will run through our TRI SPI and AOI. I have no doubt th
Electronics Forum | Tue Apr 18 10:08:51 EDT 2006 | russ
We use materials such as G10, durapol, or FR4. We put a lot of holes in the fixtures so that only enough material is left to support the board during reflow to prevent sag/ warp or whatever. We also try and keep all bot side material in unpopulated
Electronics Forum | Thu Apr 20 17:26:15 EDT 2006 | russ
Well i wouldn't run every board then!!!! okay seriously, All bad parts off the same each time or are they "all over the place" Check your mount height, you may have sagging or warped boards or just bad part height
Electronics Forum | Mon Aug 23 17:43:18 EDT 2010 | davef
SAG: Questions on solder mask webbing with fine pitch parts are: * What is the minimum pitch that you can use webbing between fine pitch pads? * What solder mask do you use?
Electronics Forum | Fri Jul 14 11:34:37 EDT 2000 | Mike F
John, The first thing to check is how tight the boards are being held in the conveyor (assuming you are using a finger conveyor). They should be a little loose at the input end so there is some room to expand. If the boards are held too tightly, when
Electronics Forum | Thu Jun 11 23:35:40 EDT 1998 | Scott McKee
| Does anybody know if a contraption exists that will minimize a PCB's tendency to become slightly bent after reflow? We have a new product that we're planning to assemble in a couple of months. The board is 9.7" by 13.4" and it is imperitive that
Electronics Forum | Tue Aug 29 18:56:41 EDT 2000 | Campbell Livingston
One of the major problems with snap off's is heat from the wave weakens the joints. Try using more holes but smaller size. V-grooves may also be an option, but depth control is a problem as most are not NC machine controlled. Direction through the wa
Electronics Forum | Thu Apr 06 08:31:13 EDT 2000 | D Scott
Angela Do you see this problem on other .5mm pitch devices or is it only on the QFP? Check placement height, too low or to high can cause you problems Pad co-planarity, are your boards HASL? Is your board sagging during placement(board supports) An
