[ezkcdude]

I really don't have time these days to sit down for 5-6 hours at a time for building, so I'm thinking of trying out the toaster oven reflow method (e.g. http://www.instructables.com/id/EBXC...623C/?ALLSTEPS). What advice does the collective mind here have about this technique? Do I need a fancy oven? Does anyone have a specific recommendation (brand/model)? I'd appreciate any input

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[AndrewB]

Take your time.
Make sure the oven tray doesn't flex or POP when heated.
Take your time.

You can use virtually any oven as long as the board fits

 

[pinkfloyd4ever]

is this a joke?

 

[Pars]

Nope, no joke. I read one guy (can't remember where) that measured his toaster oven and could almost exactly duplicate the temp curves/cycle of a commercial reflow unit.

 

[ezkcdude]

Quote:

Originally Posted by pinkfloyd4ever /img/forum/go_quote.gif is this a joke?

Definitely not a joke. Did you even look at the website I linked to? There are plenty more.

 

[Alfiax]

From what I've read, this process takes a lot of time and care and a lot of experimentation to set up right. It seems to be basically the only clean way to do high-density packages at home without shelling out for a rework station, but for run-of-the-mill SMD stuff the pick, place, and solder method seems to be considerably easier. The only exception I can think of in audio DIY work would be for an exceptionally complicated DAC or for working with extremely small chips like the TPA6130.

 

[ezkcdude]

Quote:

Originally Posted by Alfiax /img/forum/go_quote.gif The only exception I can think of in audio DIY work would be for an exceptionally complicated DAC or for working with extremely small chips like the TPA6130.

Well, take a look at my ezdac project, and let me know if it is complicated enough

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[ezkcdude]

Here's another good resource:

http://openhardware.net/Misc_Stuff/ToasterSMD/

 

[mono]

For the EZDAC it looks like it would be as easy to do a drag soldering method (gratuitous video example) or use a hot air station to reflow paste. I mean you already have a significant # of through-hole parts too so it's yet another step.

Also I don't see how you'd be significantly cutting down on solder time, would think the 5 hour figure would have to include the unpacking and placing parts prior to soldering, which is a step also necessary with the toaster oven.

I'm not trying to shoot down the idea though, had actually thought of trying it myself since I have an old toaster oven sitting around but it's a cheapie, I don't know if it has uniform temperature throughout the cavity. Main deterrent might have been cost of the paste and it's short shelf life, and quirky ordering through places like Digikey where you have to have it shipped next-day.

 

[AndrewB]

The most time intensive part is prep. Once you have the solder paste applied and placed the smd devices. It only takes about ~25 minutes at 325F for the board to flow. The only other significant time is the cool down period. Approx. 30 minutes for cool down. You do not want to disturb the board during cooling, better if you waited and hour or so.

I've built many engineering prototype boards with this method, with some very high density smd's. After the smd's are done, then you do the thru-hole components. Patience is the key

 

[threepointone]

haven't tried it yet, but from what I hear, while toaster oven reflow is good, skillet reflow is even better. So good, that from what I understand, sparkfun.com "manufactures" most of what they sell using the reflow skillet method. They have an excellent series of tutorials on surface mount soldering/fixes/stenciling/solder paste prep/everything else on smt soldering here: http://www.sparkfun.com/commerce/hdr.php?p=tutorials.

 

[Joshatdot]

I would use a Heat Gun