Inexpensive thermocouple for DIY reflow oven?

[UltraTrunks]

I may be under the wrong impression here, but I'm assuming that thermocouples should, or at least could be a very inexpensive part.  I'm building a reflow oven but I can't seem to find a part under $15.  Here's the cheapest I've found that will meet the temperature requirements.  That'll be the most expensive part in the project.  And I'm including the toaster oven cost as well.

Am I looking in the wrong place, or are thermocouples just expensive?

[Alex Eisenhut]

eBay

[UltraTrunks]

God I hate eBay, but I see there are some cheap thermocouples there.  I never really think to look on ebay for parts.  I guess it'll do.  Curious as to why you can't find reasonably priced thermocouples from the standard resellers like Digi-Key?

[Jimmy]

http://www.ebay.com.au/itm/2M-50mm-Spade-K-Type-Temperature-Controller-Thermocouple-Sensor-100-C-to-1250-C-/121192321893?pt=AU_B_I_Electrical_Test_Equipment&hash=item1c37a01365&_uhb=1

[UltraTrunks]

I guess I need to widen my net a bit when parts hunting to beyond the stardard parts places (eg Mouser, Digikey).  Looks like I found what I need on Amazon.  More comfortable shopping on Amazon than eBay any how.

http://www.amazon.com/Type-Thermocouple-0-250C-Digital-Thermometer/dp/B005CG2W3U/ref=pd_sim_indust_3?ie=UTF8&refRID=0A19RF79Z1X0FEGFCNCD

[charlespax]

Here's a stainless steel probe type on dealextreme. They have worked just fine for me, but I have received a broken one once. Maybe a 10% failure rate.

[Alex Eisenhut]

I guess I need to widen my net a bit when parts hunting to beyond the stardard parts places (eg Mouser, Digikey).  Looks like I found what I need on Amazon.  More comfortable shopping on Amazon than eBay any how.

http://www.amazon.com/Type-Thermocouple-0-250C-Digital-Thermometer/dp/B005CG2W3U/ref=pd_sim_indust_3?ie=UTF8&refRID=0A19RF79Z1X0FEGFCNCD

Good. As long as your horizon has widened. There's a lot of stuff out there!

Just as an example, I wanted to "exercise" rc airplane servos without the radio and receiver.

Just a few seconds on eBay and I found this

http://www.ebay.com/itm/221456290122?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

How can you possibly compete with that? There's a PCB, an enclosure, a pot, LEDs, a switch, connectors and a microcontroller.

I'd spend more money just to eat the food to give my brain the calories to think about designing it myself!

Nowadays when I think I need "x", I look on eBay first.

[jeremy]

All you pay for with thermocouples (in my experience) is their cal and material purity. If you're putting this thing on a smelter full of platinum, spending $100 makes sense but for just a home reflow oven the eBay ones are perfectly fine. A few degrees error is probably less than the error caused by uneven heating.