what do you use for reflow on quick, one off circuits? Space is at a premium. - Page 1
Forum section: electronics / general

author: cdev
author_rank: Super Contributor
timestamp: March 25, 2015, 08:37:27 pm
content: I kind of want to get some little electric skillet or similar for very fast one off PCbs just heat it up until it melts and then let it cool down. I have a little heatable thermometer which can go on it, it doesnt need to have a thermostat, adjustable heat would be nice.

author: Falcon69
author_rank: Super Contributor
timestamp: March 25, 2015, 08:50:43 pm
content: I built a Reflow oven from a quad element $35 Black and Decker Toaster Oven.All you need is a Thermocouple, PID, Relay, Heatsink, and a couple switches. You can also get a data logger too for your laptop so you can see the Curve of the proper heating for the solder you are using.I have a write up on the one I built over on the CNC Zone Forums.http://www.cnczone.com/forums/general-cnc-machine-related-electronics/175422-manufacturing-software.htmlI even have a wiring schematic there as well for it.It works pretty good!

author: radix
author_rank: Contributor
timestamp: March 26, 2015, 08:35:30 pm
content: I seriously need to trythisonce.

author: chicken
author_rank: Frequent Contributor
timestamp: March 26, 2015, 10:07:46 pm
content: Here's my cheapskate stove top reflow rig:- 1/4" aluminum slab- 2 aluminum backing trays- thermocoupleHeat aluminum slab to 160C - gently, it should be stable at 160C or only slowly increasing.Add tray with PCB and temp probe inside, cover with 2nd tray, wait till PCB reaches 160CWait another minute or so, then turn up the heat to max.Wait till PCB reaches 220, then take tray off the stove (don't bump it or you'll get SMD salad).Let it sit to cool down, season to taste.Propably not compatible with SWMBO

author: Fat
author_rank: Regular Contributor
timestamp: March 29, 2015, 05:47:56 pm
content: Rocketscream reflow board, I ordered the PCB and built it up. I think I'm abut $30 into the board and parts, salvage the K type temp sensor, and got a $6 SRS. attached it to a homebrewed arduino uno and run it all to a $18 toaster oven. Works great. Breaks down into components to store on my equipment shelf. it takes less than 5 minutes to set it all up.

author: cdev
author_rank: Super Contributor
timestamp: March 30, 2015, 03:02:26 am
content: SRS = solid state relay?Actually, the oven sounds good.. I have an oster convection oven I can use, then I can make larger boards and get even heat. Just need to decide on the controller

author: f5r5e5d
author_rank: Frequent Contributor
timestamp: March 30, 2015, 04:03:37 am
content: if you're dealing with high pin count fine pitch or bga digital then reflow may be needed - but hand soldering is an option for many boardseven fine pitch can be flood and mop hand soldered if you are really talking just prototypinghttp://store.curiousinventor.com/guides/Surface_Mount_Soldering/QFP/I wouldn't go below 0805 on passivesoptics - magnifiers and bright lights make a world of difference

author: miguelvp
author_rank: Super Contributor
timestamp: March 30, 2015, 04:14:15 am
content: Quote from: cdev on March 30, 2015, 03:02:26 amJust don't use it for food anymore

author: nctnico
author_rank: Super Contributor
timestamp: March 30, 2015, 06:57:51 pm
content: I use a soldering iron with tips in several sizes and/or hot air. I just can't see the benefit of messing with stencils, solder paste and an oven. With a soldering iron and hot air I can also build & test a circuit in steps.

author: Fat
author_rank: Regular Contributor
timestamp: March 30, 2015, 07:04:27 pm
content: Quote from: cdev on March 30, 2015, 03:02:26 amYes, SSR=Solid State Relay.I've read some accounts where people have just adjusted the oven manually to fit a profile, but building out the RocketScream board and doing some automation on it is part of the fun of my projects.One thing to consider is that the stock RocketScream profile is set for lead free solder. I modified mine to lower the temps and shorten the soak times for leaded solder.That little oven has been remarkable.Fat

author: Fat
author_rank: Regular Contributor
timestamp: March 30, 2015, 07:06:07 pm
content: Quote from: miguelvp on March 30, 2015, 04:14:15 amAgreed. My kids have a tough enough life without being born with three eyes and no thumbs.Fat

author: Fat
author_rank: Regular Contributor
timestamp: March 30, 2015, 07:10:48 pm
content: Quote from: nctnico on March 30, 2015, 06:57:51 pmIt can be done. We did hot air on the original two RocketScream boards we put together. It took us about 5 hours to put two together (drop solder, drop one part, reflow with hot air station, then move on, this time included the manual soldering of the not SMT components and headers). I had a third board left over. I place all the solder drops with a syringe, set the components, reflowed in the oven and then did the manual components and headers in less than 40 minutes. I would have been faster if I had all the components organized. The time savings for me is significant.Fat

author: nctnico
author_rank: Super Contributor
timestamp: March 30, 2015, 07:39:37 pm
content: I don't use hot air for small components; I use the iron for that ofcourse. Just tack one side with solder and solder the components on one side. When a lot of components are done, solder the other sides. This works very quick. I only use hot air for really big components (like soldering a TO220 to a board).

author: georges80
author_rank: Frequent Contributor
timestamp: March 30, 2015, 11:35:11 pm
content: For single sided boards or ones with most of the components on one side, I often use a temp controller hot plate. Lots of them on Ebay (search for Fisher Scientific Isotemp), they seem to be more expensive now versus a couple of years ago. They come up to temp quickly and are quite stable once at temp.Obviously you don't need the models with the stirrercheers,george.

author: tggzzz
author_rank: Super Contributor
timestamp: March 31, 2015, 09:23:22 am
content: I've documented my experiences here:https://entertaininghacks.wordpress.com/2015/03/25/assembling-pcbs-with-surface-mount-components/"This outlines how I placed solder paste, placed components, saw small components, soldered and reworked small PCBs. I didn’t want to be constrained by the time it takes to apply solder paste, position components, and reflow in the HackSpace oven, so I looked for ways I could do the whole process at home. Summary:it does work and isn’t too painful. Naturally I’m evolving methods and techniques as my skill improves."

author: tggzzz
author_rank: Super Contributor
timestamp: March 31, 2015, 09:26:16 am
content: Quote from: f5r5e5d on March 30, 2015, 04:03:37 amWhy not? I haven't had problems with 0603, yet.

author: nctnico
author_rank: Super Contributor
timestamp: March 31, 2015, 12:24:14 pm
content: IMHO 0603 is doable by hand if you have good eye sight (or good glasses). Smaller parts are trickier to do.