Reflow Toaster Oven - Part 1

Converting a toaster oven to a reflow oven is something that's been on my to-do list for quite some time now. Hand soldering really tiny SMT components is a PITA, having a reflow oven would make things a lot easier.

So this afternoon I finally got my hands on a suitable used oven :) A Tefal Activys. I think this one was also sold under the Moulinex brand. I guess it costs around 100 EUR new.

It's got the right size, has a large door, two large heating elements and no complicated electronics. It's pretty clean for a used oven, doesn't seem to be used that much. And best of all, I only paid 20 EUR for it :)

 

As some crazy ozzy bloke would say: "Don't turn it on, take it apart!"

The cover is held in place with a bunch of self-tappers, it's just sheet metal, in fact, the whole oven is made of sheet metal, sheesh.

Nothing much on the left side, just the spring for the door. There's a bit of room between the cover and inner panel so I can put some insulation in between it to improve the oven's performance.

More sheet metal on the top. Even less room for insulation, oh well. The back panel is just a single piece of sheet metal, that's going to get pretty darn hot when this thing turns on...

And here's what makes this oven tick, quite literally. No digital electronics at all. Plain and simple. Let's have a closer look.

This is the motor for rotating dead birds, that's gonna go, but the hole may be handy to route a thermocouple through.

A very crude thermostat. It's relies on a bi-metal. It's screwed almost directly to the bottom heating element.

And the temperature knob on the front is connected to it like this, expect the temperature to be off by at least 30 deg C...

And this is what makes it tick, it's a mechanical timer, with a nice ring at T=0 :) Partially shown below it is the mode selector (grill/oven/roast) which selects which heating element to use.

Another thermostat, probably a safety switch to prevent it from overheating. As you can see, the top heating element is held in place with a spring, you can pull the element down for easy cleaning of the interior.

The bottom element can be moved as well but is not spring loaded, it simply relies on gravity.

And a closeup of the knobs. 280 deg C? Probably a bit optimistic :)

2900W? Let's test that! With just the top heating element on my meter shows around 1300W. With both elements on it uses a whopping 2500W, still a bit short of 2900W but plenty nonetheless. This thing heats up pretty fast as it is already, but I'll need to do some more testing to get the actual figures. And as noted before, the back of the oven get's HOT! Not good. I'll probably add an extra panel at the back (either on the inside or outside) so I can add some extra insulation...

So much for now, stay tuned for more :)