Hi guys,
After lots of "umm"-ing and "aah"-ing, I've decided to take the plunge
and have a go at SMD reflow using a toaster oven (or, in my case, a
"mini oven").
I spent about 3 days digging through all the articles I could find on
the subject, and eventually found an article in Elektor (November 2008
if memory serves) that included a short list of features that are
required in an oven that is being modified for SMD reflow:
- Must be able to reach 250 degrees Celsius
- Heater power of around 1500 Watts
Turns out there was only oven in the current Argos catalogue that met
these specs -- sold under the brand "Cookworks", part number MG25AF,
Argos catalogue number 423/0302. The features of this particular oven
are as follows:
- Four elements (two top, two bottom), 1640W total.
- 25 litre oven capacity
- Timer up to 120 minutes
- Thermostat settings from <70 to 250C
- Can switch the elements on and off via a front-panel switch. Either
all on, top only, bottom only or all off.
I haven't had chance to etch a PCB and solder it (yet), but I did put a
thermocouple in there tonight, set the timer to the full 2 hours (but
only ran it for about 20 minutes total), all elements on, and full heat
(250 Celsius). The sensor was a Labfacility Z3, fibreglass-sheathed,
connected to a Maxim MAX6675 K-type thermocouple interface IC
("thermocouple to digital converter" according to the datasheet).
I could upload the CSV file containing the captured data, and the
OpenOffice (ODS) spreadsheet file containing said data, nicely graphed.
It covers the time from switching the oven on, to it oven heating up to
~300C (despite being set to 250C), the oven being switched off, and then
the oven cooling down to ~50C with the door closed.
Thanks,
--
Phil.
ygroups@...http://www.philpem.me.uk/