On Sun, May 1, 2011 at 2:14 AM, Jesse Lackey wr= ote: > Hi - I have a $50 "delonghi" toaster oven from ebay (4 heating elements > and internal fan - I consider the fan essential for even heating) and a > $30 mastech MSD838 DMM from jameco.com that has a thermocouple. =A0The > setup works well. =A0I only do lead solder. =A0Basic "profile" is to powe= r > up and go to 120deg C, wait a minute, then go up to 205-ish deg C for > 5-10 seconds, then off and open the door an inch, and wait for cooldown. > =A0You can watch the solder melt thru the glass door and have some > confidence everything has reflowed. =A0And yes, I have plans for doing a > reflow controller to make it so the profile is repeatable and closer to > ideal and so I don't have to watch it, but ... low priority. Good tip about the fan. I didn't think it mattered that much because of the distance between the elements and the board, but I'll try to get a unit that has one. > For stencil prints, I have this: > > which was not much more than $200 when I got it 2 years ago. =A0(is $375 = now!) > and use stencils unlimited for the stencils as well, but I've only had a > couple made. I was hoping to find someone locally with a laser cutter and get a few plastic ones cut. There seem to be a number of folks using mylar. > All this is fun stuff, but until one has a pick and place machine, it is > of fairly limited usefulness. =A0It is definitely faster to do SMT reflow > (even w/o a stencil, and just use a syringe to deposit the paste on pcb > pads) than to hand-solder each part, but the bigger picture is that if > you're doing this for more than just a few pcbs now and then, you should > figure out how to do the business/cash-flow of having it done by a > contract manufacturer, unless your time isn't tight/valuable; depends if > your undertaking all this as a career or high-end hobby. =A0And if you're > only doing a few pcbs now and then, the time savings vs. just > hand-soldering 150 parts on 3 pcbs isn't that much; a few hours, maybe. That's what this would be for me...a bit less of a hassle when soldering. I don't do large scale manufacturing, and my time isn't that tight for the stuff I am doing. I am looking at a project idea that I'll need to do about 30 boards for which has sparked a renewed interest in reflow. I could do them by hand...but why not try something new? > At least that's what I've come around to thinking over the last few > years. =A0And after several false starts, I still don't have a p&p, and > likely never will. I doubt I will either. I don't do the volumes to make that worthwhile. > Anyway, my 2c on the whole thing. =A0For around $100-$120 you can get > solder paste in a syringe, toaster oven, themocouple DMM, and have fun. > =A0I strongly recommend curved tweezers for doing pick&place of passives > and most ICs; little hand-held suction thingies for ICs are mostly not > useful in my experience. =A0Don't be tempted to use the toaster oven's > built-in temperature readings, at least on mine it is horribly > inaccurate. =A0Get a DMM and place the thermocouple at a good > representative place and you can have a good idea of what's happening. I already use paste, but manually. I use curved tweezers for p&p. I think one of those suction guys came with my hot air station, but I've never tried it. I already have a DMM with temperature, so I'll use that. I didn't think it was going to work with front panel controls on the toaster...there's no reason they'd be manufactured with any accuracy. I also have an IR thermometer, but I'm not sure if it works accurately through the glass door to measure the board. Thanks! Josh --=20 A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools. =A0 =A0 =A0 =A0 -Douglas Adams --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .