Show me your temperature probes - Arduino

I just got an Arduino micro controller and I'm getting ready to integrate it into my HERMSish setup. I've been using a PID with a K-type thermocouple that works well with the PID controller.

I've been reading around about the Ardunio and temperature control and it sounds like thermocouples are not the best option. A thermocouple is noisy and requires a $12 chip like this MAX6675. http://www.sparkfun.com/products/307 It is also difficult to read multiple sensors with one Arduino.

A thermoresistor may be a better option or a Digital Temperature Sensor like the DS18B20 http://www.sparkfun.com/products/245

I need a stainless 1/4" probe that I can use with a compression fitting in my setup. It should interface well with an Arduino and still have the ability to read up to 4 probes and run a 7 segment display http://www.sparkfun.com/products/9480. Low cost (No $12.00 MAX6675 needed) and glass wire-wrap/insulation is a plus.

Thanks for your input!

these stainless steel probes are great. they fit the 1wire temperature sensors well, and made by a member of this board also. http://www.brewershardware.com/Temperature-Probe-Ends/

Brewer's Hardware also sells pre-made sensors on his site. You can find the DS18B20's on his site here: http://www.brewershardware.com/BrewTroller-Sensors/

Thanks for the links. That might do the trick.

I'm cooking with gas, so I'd like to have glass braid wire-wrap/insulation on the sensor. If I make my own, I need to find a source for the wire.

Using the stainless probe ends http://www.brewershardware.com/Temperature-Probe-Ends/, how would you recommend sealing the DS18B20 sensor in the tube? Can I use high temperature epoxy or liquid gasket instead of heat shrink tubing. This would allow me to slide a 6 inch probe down into a 16" thermowell inside a carboy.

I used four MAX6675 chips with an Arduino and K thermocouples for a while. I hated the whole thing. The chips were free samples, so I didn't have too much to lose. They weren't that tough to interface. However, I never figured out how to remove noise from the system, and it could be wildly inaccurate at times. I'm in the process of converting back to DS1820 sensors.

i tried putting one inside some tubing and use aquarium sealant on one end with mixednresults. i like using the probe with heat shrink tubing on the other end. not fully submersible but will work for most applications. i plan on getting thermowells from brewers hardware soon to better monitor fermentation temps.