Jim told me he doesn't bypass the safety features with this new setup. So you're left with the same problem aka roaster feature set, not one that's worse. What you described is just what I faced today running five loads. It took forever to go through its cooling cycle.

I manage to achieve 4 x 250 grams roasts in 2.5/2.75 hours with my computer controlled (RoastLogger) Hottop.

After each roast I strip down to the chamber & blow all chaff out with a cold-blow hair dryer which seems to bring down the temp to around 50C/60C. I use the 'Reset' button & start over again with the next roast.

Don't seem to have a problem with this taking overall around 40 minutes to roast a 250 gram batch

I'm happy with this sort of time.

Ron

iginfect wrote:..... Just finished my first roast and see a long learning curve ahead. Thanks to JimG and Tom.
Marvin

iginfect wrote:There were times I needed to do 3 roasts and it basically took me all morning, waiting for the HT to cool between roasts. Is the new mod making it worse or just leaving the same problem?

Marvin

Congratulations on getting everything working and completing your first roast Marvin. Having completed the installation do you have any advice for others in particular on the choice of thermocouples and there installation?

On the issue of the Hottop requiring cooling cycles between back to back roasts, the installation of the HT Roaster Interface does not change the behaviour in any way. The Hottop is an excellent roaster but it's design, with the electronics and drive motor in the rear compartment, in close proximity to the roasting chamber, does limit it's ability to do continuous back to back roasts without a cooling cycle between roasts. The cooling cycle reduces the average and peak temperatures experienced by the electronics and drive motor. Defeating the built in requirement for the cooling cycle would result in these components being subjected to higher temperatures. This is most unlikely to result in failure in the short term but would probably reduce the life of the components.

For these reasons we decided not to provide a way to defeat the normal Hottop cooling cycle requirement.

At GreenBean's request, parts I used or recommend(some already stated):

1. Kapton® Insulated Thermocouple Wire type K 30 Ready-Made Insulated Thermocouples - Package of 5. http://www.omega.com/pptst/KK_WIRE.html
They come beaded at one end. They are very hard to strip and it is difficult to tell the red from the yellow. They are thin and easy to route, much easier than what Randy shows in his manual.

2.Watts A-8 delrin sleeves and inserts 1/4" in plumbing section for compression fittings at Lowe's. The delrin inserts are thrown out, the metal sleeves get JB welded to the back of the wall as on page 2 of this thread.

3.White SiliconeTubing, 1/16"ID, 1/8"OD, 1/32" Wall, 10' Length
http://www.amazon.com/dp/B000FOEM3M/ref=biss_dp_t_asn This fits into the sleeve and is not too tight for the TC

4. Loctite RTV Blue Silicone gasket maker, from Lowe's in adhesives, not caulking section, to bind the tubing/TC to the sleeve.

5.from McMaster-Carr
Metric Nylon Pan Head Phillips Machine Screw, M3 Size, 8 mm Length, 0.5 mm Pitch, packs of 100 94879A118 $6.86
Metric 18-8 Stainless Steel Female Threaded Hex Standoff, 6MM Hex, 14MM Length, M3 Screw Size 94868A009. Actually used nylon 15mm lenghth, recommend 10-12 mm, available on ebay from Hong Kong.
Used M3 nuts, SS from McMaster-Carr but recommend nylon, either McMaster-Carr or Ebay

6. L bracket and aluminum sheet, to attach to outside wall, Lowe's Hardware section in pull out drawers for hobby.

7. Screwdriver set from Radio Shack for screwdriver to fit M3

To quote Ronsil, if I can do it, anyone can. It just took me forever.

Marvin

Hi All,

There was a whole lot of buzz about the HTC/TC4C across many of the coffee forums back in Sept/Oct when the boards were first released, but virtually none since then. The silence for the last few months seems uncharacteristic considering how vocal the Roaster enthusiast groups usually are. I even looked on Randy's site expecting to see something about it, but not even a peep.

Does anyone else have any first hand experience with the production boards?
Which thermocouples did you use?
How did you mount the board and thermocouples?
Whats your opinion of the HTC/TC4C/RoastLogger combo?

The boards arent all that expensive, what scares me the most is the downtime on my roaster! I would hate to have to go back to Counter Culture again....

I want to pull the trigger on this one but I would love to hear some success stories if anyone has any.

Mike Petro
Martinsville, VA
--------------------------------
PLC/PID'd Lady Silvia, Stepless Rocky, HotTop-P2 (soon to be hacked)
http://mikepetro.org/coffee/

I am surprised as well that there is nothing on this on my website.
I have been really swamped over the last few months since finishing the manuals for RL and the boards. I have been working some jobs for clients (a website from scratch as well as a couple of advertising banners, one of which was 8feet x 10feet), taking care of mom's financial and legal matters since we had to place her in a nursing facility, packing up her stuff and selling her home, having a bit of a life, and trying to have a bit of free time in between.

I have done about 40 roasts with RL + TC4C/HTC setup and HIGHLY recommend it. For most purposes, it gives user-control and repeatability over the Hottop it should have had a long time ago.

How dare you actually try to have a life beyond coffee!

Seriously though, thanks for responding Randy. I feel for you on the Nursing Home bit, I had to do that with my Grandmother, it can be an emotionally draining experience.

Regardless of which controller I end up with I know I will need to add ET and BT probes, and quite frankly that is the most challenging bit of this whole thing. I work with Industrial automation and we have hundreds if not thousands of thermocouples throughout the plant, so I am no stranger to them. I know you have favored exposed junction probes for the faster response time, I am just concerned about the durability of those with beans constantly hitting them. My industrial background (and gut) has me leaning towards a sheathed probe for durability. How much difference does that little bit of response time actually make in real life on this Roaster? Have your exposed junctions ever failed?

I have been considering a single element version of the following probe. The smaller diameter probes are still reasonably fast. It would mount easy, just drill a hole, no JB Weld needed. I have 1/8" pipe nuts that would hold them in place, sort of like a bulkhead fitting.

http://www.omega.com/Temperature/pdf/TC-NPT.pdf

[*]Is there 2.5" of clearance between the backside of the wall and the motor bracket on a P2? I guess I could remove the strain relief if need be.
[*]At 3/4" into the drum I might have to bend the probe ever so slightly, if at all, to clear the fin on the drum.
[*]The safest thing would be an ungrounded probe but that is another hit in response time, does it really matter?
[*]How much problem have people had with ground loops on the Hottops?

Thanks in advance for any and all responses....

Mike Petro
Martinsville, VA
--------------------------------
PLC/PID'd Lady Silvia, Stepless Rocky, HotTop-P2 (soon to be hacked)
http://mikepetro.org/coffee/

There are others here far more qualified to comment on probes. The problem with the sheathed probes is that they are slower to respond. The grounded ones will respond a bit faster but the most common reported problem I have read comes from grounding difficulties, and it would be difficult to isolate them from teh chassis if a problem arose.

I used thermocouple wire and just twisted the ends and mashed them a bit. If you have access to a welder to make your own, that would be the way to go. The lag is about one minute as it is, so you want probes that will respond as quickly as possible. I would certainly recommend using a bare wire probe for the ET at least.


As you can see, it can get a bit tight in there.

Mike Petro asked for success stories. I've done 24 roasts, the first 4 was a learning process and were discarded. It was well worth doing, there is more control and repeatability. I am now able to cut the heat just before first crack to lengthen 1st c. My roasts are better and more predictable but there is always some small variation as ambient temp, humidity, aging of beans etc. change. It was well worth it, including the month w/o a roaster and buying from Counter Culture.

Marvin

Thanks Marvin and Randy for your feedback. I went ahead and pulled the trigger on the HTC/TC4C boards. Now for the fun part of sourcing the thermocouples. I may start a new thread on that subject.