SMT reflow oven - Argos £13.24

Ok, so I was a bit naughty with that title, but this could be a good 'donor' oven to rejig & make into a SMT reflow oven.

http://www.argos.co.uk/static/Product/partNumber/4230285/Trail/searchtext>COOKWORKS+MINI+OVEN.htm

I've reserved one & will collect it tonight (I'm hoping it has the right type of heating elements in the top/bottom - it looks like it might)

got to wonder how it's possible to make this (not exactly lightweight) item on the other side of the world, ship it to the UK, transport it to the Argos shops, store it & then have staff collect your dosh & retrieve it from the storeroom & still make a proft at £13.24!

unbelievable.

I'm hoping someone here will buy one too, then I can ponce their PICBasic 'reflow oven' program off them!

Hey Hank, did you get your oven yet?

Not quite sure how I missed this thread.

I have a "SMD Easy Bake Oven" similar to that one. (Mines actually a convection oven also). Got it at wallmart for about $70 USD.

It works quite well, but it took some "hotrodding" to make it happen.

Here's a few tips I can share about mine...

1) Make sure to get a convection oven. A convection oven will have a fan to circulate the hot air and that helps give more even temps and reduce hot spots in the oven.

2) Get the highest wattage oven you can. Most small ovens don't really have enough power to get to the temperature you need quickly enough. I added a large step up transformer to mine so that the heating elements run on about 145 volts instead of the "standard" 120v. That gets mine up to temperature plenty quickly enough for lead based solders, but it's still marginal for Pb free work. Out of the box, it was rated at 1500 watts, but now it draws about 2KW.
I'm sure that overrunning the elements like that will dramatically shorten their lives, but for the few minutes a month that I use it I'm sure it will still last a long time.

3) *Read the data sheets* for the maximum reflow temperature and time that's safe for EVERY part on your board. Some parts, like LEDs and electrolytic caps are more delicate than others. It really sucks to have a part(s) die because you over baked them!

4) If you decide to get a hot air rework station to go with your toaster oven (and if you do much SMD you'll definitely want a hot air station) DON'T buy an Aoyoe. Mines a pile of garbage and I hate it. I wish I'd spent more money and got a good one.

The temperature controller for my reflow oven is simple. It uses a type K temp probe, a parallax BS2, and a solid state relay to turn the heating elements on and off. During most of the baking cycle, the elements are fully on because it takes all the heat they can produce just to get the oven temp to ramp up quickly enough. But there is a spot around 160° C (the Soaking Zone) that the power is backed off a little for about 1 minute, then it's cranked full up again for the reflow zone.

All in all I'm pretty happy with my reflow toaster oven, although it really does need a little more power for Pb free work.

Good luck with yours! It's a great tool to have in a world where SMT rules and through-hole parts are quickly becoming dinosaurs...


steve

Hi Steve,

(apologies for the delay in replying)

Since buying it, it's sat in the corner a little...but yeah, upon reflection I should have bought one with a fan in to even out the heat a little...I got drwan in on the ludicrously low price!

to be honest, I'm now even beginning to wonder if I can be bothered to 'roll my own'. The Chinese ones aren't *that* expensive...& life's short eh?!

Appreciate the tips you've put my way - the bit about Aoyoe is very timely - I was pondering one just this morning - I'll give them a wide berth (any recommendations - ie what do you now wish you'd bought instead?!)

Thanks,
Hank.