iginfect,

Try reversing the thermocouples on the board (switch T1 and T2 probes) and see if it now reverses the display discrepancy. This would show that the probe is bad. Hopefully that is the problem.

Echovolution wrote:Any update on the availability on the TC4C and the HT Roaster Interface. It seems like the sale of both of these have been suspended for the last few months. Even the temporary "RL-HT-CTRL" interface is not available at this point....

http://www.mlgp-llc.com/arduino/public/arduino-pcb.html
http://www.mlgp-llc.com/htri/
[urlhttp://roastlogger.co.uk/coffee/roastlogger/rl-ht-ctrl.html[/url]

Unfortunately Jim is still not back in production of his boards (HTC/HTShield, TC4/TC4C etc.). Several people have registered an interest in obtaining a RL-HT-CTRL board in the last few months. Due to this I am, as promised, considering building another batch of RL-HT-CTRL boards in the near future. All those who have registered an interest have been provided with the relevant details and asked to confirm if they wish to go ahead. If anyone else, who has not yet registered an interest, wishes to obtain a board please let me know as soon as possible and I will send them the relevant information. My email address is listed in the feedback section of the RoastLogger website.

Further information on the RL-HT-CTRL board is available on the RL-HT-CTRL webpage and the review by Randy Glass.

ronsil wrote:I used 25mm M3 nylon screws & 10mm spacers. Remember to get the extra nuts to act as spacers to keep the new boards away from the wall. Mounted this way you eliminate the problem of making & fitting a shelf.

Good Luck

Ron

Bob_McBob wrote:Are you saying you used new 25mm M3 nylon screws, with 10mm threaded nylon spacers, and nylon nuts below? My board stack has 12mm spacers, which seems to be the minimum for the component height.

Where does one purchase 25mm M3 nylon screws, 10mm threaded nylon spacers, and nylon nuts?

For one reason or another I am having one heck of a time trying to hunt these down without having to buy them in packs of 100 count or shipping them from outside of the U.S. I have sifted through ebay, amazon, google. Also have been to radio shack and local hobby stores. Not sure why I can not find em

These items are the last pieces of the puzzle before I assemble this mod. Any guidance is much appreciated

McMaster-Carr and Ebay were the source for me of similar small parts. Even if buying 100 of screws or nuts, it is still cheap compared to the price of the HT or the TC4-HTC hardware and is just part of the price of the roaster. An upgrade from here is a roaster of thousands of dollars and the how do I install with vents, carts, shacks/outbuildings etc.

Marvin

Thank you for the quick reply, I guess 100 count it is.

I am not really concerned about the price, its more about not wanting ~96 screws, nuts, and spacers sitting around that I more than likely will never use. I try to minimize 'waste' when possible.

Randy G. wrote:Others have asked that, but I believe that they are quite expensive compared to what generic thermocouples are already available aftermarket. Hottop USA doesn't list them on the website.Cost on the ones I made was about $18 plus my time to put them together. Ad another $6 for the compression fitting. I am not selling them but posted that just for a cost comparison.

So, has anyone actually done this and used the Hottop thermocouples for this.
They're $40 each, which, although costlier than most options, is not vastly so.
If it's otherwise a good and simple solution, I probably will opt for it.

I'm planning on doing the TC4 upgrade on my B-2K and would get 2 more of the K type thermocouples.
My goal is to make the installation easy, sufficiently accurate and robust.
I'd also like to avoid epoxy or anything not removable in case the thermocouples need to be replaced.

Any thoughts?

Try using just the stainless steel tubing epoxied through the back wall, protruding a bit into the roast chamber. Then hold the bare-wire, insulated welded thermocouples using silicone tubing, This thermally and electrically insulated the thermocouples from the chamber as well as making them a lot easier to remove for cleaning, repair, etc. I think that Omega has packs of five thermocouples for around $40 or so. This system allows more flexibility in choosing mounting locations since the small diameter of the metal tubing takes up a lot less space than the original HT probes.

I assume that's Omega 5TC-GG-J-20-36, or similar.
How does that compare to using the XCIB style 3 that they sell? I realize that latter are more expensive but it's about $80 compared to $40 since I have to buy a five pack of the cheaper one's.

I'm guessing the 5TCs are more adapable but less durable. Is that about right?

Randy's recommendation is definitely more flexible and cost less. I got a used B2k recently and this is the solution I ended up with after reading through a bunch of stuff. I followed this post from RAG to get started: RAG's post. RAG uses mikepetro's solution

I then followed frachlitz' post but I bought a different thermocouple. Based on mikepetro's post, his 2.5" probes are a bit too long. I ended up getting the 2", ungrounded, version: HTTC24-K-116U-2

The probe is 1/16" so is a bit thin. The thermocouple wires also look to be thin and delicate but they should be Ok in a roaster. With the suggested thermocouple fittings you won't need to use glue and silicone tubing to mount the TC probes.

Note that I am still working through the electronic stuff so I have not actually installed or tested anything yet.

BarryR wrote:I assume that's Omega 5TC-GG-J-20-36, or similar.

The ones I used were 5TC-GG-K-20-36