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Just as a preface, I’m not affiliated with this company I just like this product and thought I’d share my experience in case anyone else was interested
I was looking to build a PID controller for my bender and while browsing the Auber Instruments website for components I saw a complete unit for cooking rice, but it used a more sensitive but fragile thermistor. After talking to their technical person and describing that I wanted to use it to bend guitar sides, they made one for me calibrated for use with a more durable K-type thermocouple for about the same price. The controller is isolated with a solid-state power relay so it can handle 1800 watts and has six programmable timer steps of different temperatures.
I tried it out using a 500-watt heat blanket on top of a side and 600 watts of light bulbs on bottom, both controlled by the PID. Worked great, held the temperature very steady for the amount of time specified. As the specified temperature approached I could watch the controller working by seeing the lights switch on and off. I got a nice bend on some EIR, very little spring back, no scorching. I’ll eventually do away with the bulbs.
It was an easy plug-in and go option for me, because I really didn't want to spend the time picking out each component (Relay, thermocouple, PID controller, wire, project box) and building it myself.

Very cool! Can you share with us the price and contact information? Who did you work with to get the K thermocouple version?

Yes I too would like to more about costs and details.

Looks like the website is painted right on the controller. It will beep when the side is cooked and ready to eat !!!

http://www.auberins.com/

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"After forty-nine years of violin building, I have decided that the search for a varnish is similar to the fox hunt. The fun is in the hunt."
Jack Batts Maker and Repairer of Fine Violins

Mark, like Chuck pointed out the website is on the picture of the unit. I bought it back in September and paid around $150. I don't recall the name of the person I talked to but I do know he made more than one that accepts a K thermocouple because a friend of mine bought one recently. Unless it was just added, the version I have is not shown on their website.

I know the thermocouple is the part that senses the temp but how is a "K" thermocouple different than the other types shown on their website and why is it necessary, does it have something to do with it's physical size or some other thing?

René

Haven't looked at his website lately, but a k thermocouple is just a general purpose sensor made of two wires of different metals put together, durable. When I was looking back a few months ago he was using thermistor sensors (a resistor with a resistance dependent on temp) which are more accurate but are essentially made of glass, not well suited for squeezing between slats.

I was in touch with them this morning here's the link for the unit:

http://www.auberins.com/index.php?main_ ... cts_id=161

Thermocouples are indeed made up of two different alloy wires twisted or joined by crimping, the type of wires used determine the type of couple ( J, K ) it is. The characteristics are different so a controller must be matched to the type of couple used, most industrial controllers have a program parameter that selects the type being used. For accurate measurements the couple and the controller must be matched K to K etc.

Before retirement I was a controls electrician in a Chrysler plant paint shop and we created our own Thermocouples for controlling the paint oven radiant wall temperatures by twisting the bare thermocouple wires together and crimping them in a ring connector that was screwed to the wall. These lasted real well until the cleaners damaged them with power washers. The probe type couples are similarly constructed but the twisted pair is embedded in the probe, these read slower as the probe needs to heat up.

I looked at their web site and think that this unit is also very interesting and with a 10 amp relay will fit out needs also
http://www.auberins.com/index.php?main_page=product_info&cPath=1&products_id=1

Fred

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Fred Tellier
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I was in touch with them this morning here's the link for the unit:

http://www.auberins.com/index.php?main_ ... cts_id=161

That's a neat little package!
Would anyone know of a supplier for a typeK leaf-type thermocouples?
The leaf-type, being flat (as a leaf), works good inside the sandwich.
Thanks
Nelson

Edit--Forgot to mention that Omega has the leaf type but I'm looking for one without the adapter plug.

Cut the plug off and connect the wires direct to the terminals just don't put the wires on the wrong terminals it will be very inaccurate.

Fred

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Fred Tellier
http://www.fetellierguitars.com
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Thanks for the tech info and that link, Fred.
That's starting to get into the 'reasonable' price range for me.

Cheers
John

I use a similar unit and it works real good, the only thing I would add is a cheap bathroom timer. I use one just in case I get distracted after the bend is complete. I set for 15 minutes when I turn on the blanket and when the timer is done so am I, a 10 minute cook after I am done bending which seems to take 4 to 5 minutes is enough. If I am leaving it overnight before pulling out I am done cooking, but if I want to do a second side in the same day I do a second 10 minute cook after the side is cool and pull it out when it cools again. I can do the 2nd side after 3 or 4 hours.

I spent about $60.00 for my controller, timer and built a wooden box to mount it all in.

Fred

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Fred Tellier
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Hmm, Well, I have had a heating blanket system that does all of this for 4 or 5 years. I set the temp that I want, and the time, and away it goes. Shuts itself off at the end. And I don't have to mess with a separate thermocouple because it is right in the blanket. Actually in all 4 of the different sized blankets that I have. And I just have to plug the blanket into the controller and the thermocouple and all is on one plug.

A guy down in North Carolina made it up for me and it works like a charm

Grant