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Hey all I am venturing into making a DIY reflow oven. Been looking at many different types/styles over the last couple of years and feel now is a good time to start one.

I originally planned on building this type of toaster oven. Looked nice with a touch screen and all. It also didn’t use the stock heating elements. He used a circular halogen heating element. After talking with the guy he finally put his source code for it on his GitHub. I’ve watched his video over and over again so I could draw out the schematics and needed parts since he didn’t bother providing those in his GitHub.

I recently ran into a listing on Amazon for a mini toaster oven which looks like this:

enter image description here

The total watts is 550 and I know by research that it’s best to get an oven that’s between 1200-1500 Watts so this mini toaster oven falls pretty behind in that regards. However, those toaster ovens are twice the size of this mini toaster and I know the less area needing heated the less watts that would be needing. I would also consider getting one of those circular halogen to replace the top stock one in the mini - if it fits that is. Doing so would put it into that 1200-1500 watts that are suggested.

The size of the mini toaster is 8L x 6W x 7 inches height. Compared to a average cheap toaster oven measuring 15L x 10H x 11 inches height. They seem to go up to bigger sizes as the price gets more.

So, to those of you who have made their own toaster oven before - is this doable for unleaded solder with, of course, small pcbs?

UPDATE on 962+ having Asbestos

That pretty much settles that then...

enter image description here

StealthRT
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  • That 1200-1500 Watts is probably just based on the size of your typical toaster oven. That mini oven seems like it might be limiting though but I wonder about evenness of heating. – DKNguyen Jan 23 '22 at 01:55
  • The success may depend on the size of parts onboard and variation in temperature on the surface so that liquidus duration follows suggested profile – Tony Stewart EE75 Jan 23 '22 at 02:08
  • Graph it out with a temperature probe. If it can get the board to the right temp in the right time frame then it's good. If it can't then it's no good. It's all a matter of trial and error and adjustments. Otherwise if you want something that will work out the box buy a commercial product. – Passerby Jan 23 '22 at 02:31
  • I thought we had a policy against threads on product recommendations. – GT Electronics Jan 23 '22 at 02:54
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    @gt this isn't a product recommendation question, per say. – Passerby Jan 23 '22 at 03:20
  • I have done reflow with an unmodified convection toaster oven. Someone before me figured out the time and temperature setting that worked well for our leaded solder boards and I have used those settings without much problem. I believe the convection fan is important to make sure the temperatures stay kind of even. The fan is not strong enough to dislodge components. – user57037 Jan 23 '22 at 07:22
  • @GTElectronics the actual question in the OP is "So, to those of you who have made their own toaster oven before - is this doable for unleaded solder with, of course, small pcbs?" Doesn't feel like a product recommendation question to me. But I definitely see your point though. The lead up mentions a lot of specific products. – user57037 Jan 23 '22 at 07:29
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    @GTElectronics SE says you can't ask questions about products, there is nothing that I know of in the meta or the help center about talking about a product in answers (if you are associated with the product, you must provide a disclaimer or it's spam). This is the main post and it comes from Jeff Atwood https://stackoverflow.blog/2010/11/23/qa-is-hard-lets-go-shopping/ – Voltage Spike Jan 23 '22 at 18:19
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    I would normally close a question such as this, but the OP has done the due diligence for a repair question: [ they ] "must involve specific troubleshooting steps and demonstrate a good understanding of the underlying design of the device being repaired." This question has research done – Voltage Spike Jan 23 '22 at 18:24
  • @VoltageSpike I appreciate it. – StealthRT Jan 23 '22 at 18:25

1 Answers1

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So, to those of you who have made their own toaster oven before - is this doable for unleaded solder with, of course, small pcbs?

It depends on what you are doing. The main question to ask is do I want it to follow a certain thermal profile. Some people use skillets to assemble boards and throw the boards on the skillets and then watch the temperature reflow by eye. Some components will fail (like optical components or some humidity sensors) especially fast if the profiles are not followed exactly.

For unleaded solder, it's possible, the reflow times might run a little hotter than lead solder. (on the oven at work we have a profile for lead free solder that runs the peak temp a little longer). If the solder isn't flowing, then you may have to touch it up or create a profile that has slightly higher or longer temperatures.

If you are doing hobby work it probably doesn't need to be an exact science (after all if a component fails you can whip out the soldering iron and replace a component). If you have to replace a component on a production run of 10000 boards it could "bankrupt" the budget.

At work I build my own boards and it's not a huge thing if components fail, we just replace them. So it all depends on your tolerance for failure (failure can also be costly for time also, so that's one thing to consider).

I would just get a cheap chinese reflow oven, no assembly required, the price would be about the same and you could spend that extra time saved on assembling an oven on assembling PCB's and designing new things.

Voltage Spike
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  • yes I was thinking of doing the cheap Chinese reflow oven but many reviews say you have to spend more in order to get it up to being any good. There's also that T962 issue in having asbestos [shorturl.at/eBLW1][shorturl.at/lEPZ9] – StealthRT Jan 23 '22 at 03:27
  • I have been using my T962 for about two years and it has been working great. I have made no modifications to it. There was no asbestos in it, it is fiberglass. It will not do a large area very well but I do up to 3" x 4" without any problems. It is not perfect but I am prototyping, not production or approval product. – Gil Jan 23 '22 at 03:44
  • @Gil, that's exactly what I have, only used it once though – Voltage Spike Jan 23 '22 at 06:59
  • @gil volage spike do either of you have a link to the software for those-if yours came with the usb connection that is. – StealthRT Jan 23 '22 at 18:04
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    https://hackaday.com/2014/11/27/improving-the-t-962-reflow-oven/ – Voltage Spike Jan 23 '22 at 18:17
  • A bit of caution with the T962 oven, be sure you select the curve for the solder you are using and the PCB is designed to work at those temperatures. I have now successfully put parts on one side, reflowed them then placed parts on the other and reflowed them again. My biggest problem is finding flux in a syringe that lasts more than a few days. Next board will have a solder mask. – Gil Jan 23 '22 at 20:56