I thought I'd start a thread where owners could post a write up & pics of mods they've done to the Hottop. If you've posted something previously consider moving it here so we have them all in one area.
I'll start off with a pic of my new wooden (Cocobolo of course!) drum cover knob salvaged from my ill fated SJ project. No more burnt fingers!
HT Knob.JPG (78.13 KiB) Viewed 50783 times
A couple pics of my T/C install based on the write up here: http://www.espressomyespresso.com/ Ignore his cover hole measurements(10mm/12mm) as they are way off. I used 13mm & 18mm. The measurements for the lower section are fine.
TC in Cover.JPG (59.21 KiB) Viewed 50782 times
TC Assy.JPG (107.27 KiB) Viewed 50782 times
TC Inside view.JPG (64.66 KiB) Viewed 50781 times
I've been thinking about adding a dimmer switch which would tie in between the board & the heating element. This way I could control the heat without affecting the fan speed the way a power control would. Has anyone tried this? Thoughts?
My Hottop is the original Hottop. I have changed the internal wiring so that the heating element can run directly off a Variac, enabled via a toggle switch. If the switch is turned on, the heating element is on, 100% duty cycle. If the switch is off, the heating element is controlled by the Hottop. In either case, the voltage that the heating element sees is whatever I have set into the Variac. This is a common hack of the Hottop, and you can find directions to do it on the internet. I typically use 130V for roasting, and push the roast much harder than the Hottop would normally do. My standard roast hits 400 deg F at 10 minutes.
I do not recommend this change, unless you are very committed to paying close attention, and are not easily distracted or lose focus. If you accidentally leave the switch on, the heating element is on, period. If you forget to manage the switch appropriately, you have all kinds of serious safety problems.
By pushing the heat, the life of the heating element is reduced. I am guessing that the heating element is good for, say, 200 roasts using it the way I do. Heating elements are not expensive and are easily replaced.
It would be nice to be able to crank up the power on the heating elements. I just went with a dimmer switch mod which ended up a little more complex than I originally expected. It turns out that the dimmer has too much loss to use it for the fast ramp when you want maximum heater power. I thought about completely bypassing the HT control circuitry but didn't like the potential safety issue. What I ended up with is a relay that switches between normal operation or, at the push of a button, routes the heater power through the dimmer. The nice part is that the HT control is still fully funtional so I don't need to be as concerned about watching it like a hawk. I've done about 40 batches with the new setup and it is really nice. Sometimes I forget to switch back to "power mode" at the end of the run and wonder why it is taking 10 minutes to do the pre-heat, but I am learning......
Of course if you have a "B", none of this is necessary in the first place!
Man, I can't believe how complex this whole coffee thing is. After roasting for a month or so with a WhirlyPop I got a Hottop B to help improve my consistency which it did but I'm discovering how incredibly subtle changes make big differences. Anyway, it's not a "mod" so to speak but I think this is a huge help:
Chronolite 1.0.1 timer for the iPhone.
It allows you to keep up to 4 timers running and they all start at once. I have one named 1st crack, one 2nd crack and one eject and you just tap that timer to stop it and record the time. I hate the Hottop timer that counts down - it makes no sense what so ever and if you use it you need to always drop the beans at exactly the same time which might not be the same temp. I asked why they did that and Michael said he didn't know - they just always did and couldn't change it.
Anyway, this little timer makes it very easy to keep track and it's helped me with my consistency and that's helping me with my coffee. Oh, and the "lite" version is free too which is a pleasant surprise.
Hey John, Thanks for starting this thread! I'm up to 40 roasts on my new Hot Top roaster (B model) I've yet to do any mods to it but would like to play around with a bean mass probe like you did one of these days. If you don't mind, talk some about your experience with the bean mass probe, how you use it, etc.
I've been doing more mods then roasts lately including installing another t/c to give a much more accurate ET readout then the HT sensor provides. I also modified the rear filter assy to give more air flow so that the fan will draw the smoke out the rear (I hope) instead of pouring out the bean chute. Omega is making me a T/C that is designed for use in ovens/furnaces which I should receive early next week. This will replace the ET t/c I installed last week which was a cheapy that I had laying around that I wasn't happy with. Once I have a chance to try out the fan mod I'll post more info if its successful. Also have a UBM EM100 Energy Monitor in route so I can see exactly what my voltage is throughout the roast. Should also be interesting to check electrical consumption of some of our appliances.
As to the BT t/c I'd consider that a must do. Just don't drill your hole in the chute cover using Randy's measurements if you use the 6" probe. Using the BT readings you will see that your temps match the temps listed on SM roasting chart & you will see how far off the HT sensor really is. The actual temps in the drum when the HT reads 167°f & starts beeping are 275+ at the bottom & 350+ in the upper section.
I picked up a B control panel last week so I now will have more control over the heating element.
I had an Omega TC in my PID'd Gaggia Classic espresso machine. They were nice people to do business with when it came time to replace the TC. Admittedly, I tend to use my hearing senses when roasting. Guess that's a throwback to roasting in the Behmor=:-)
shakin_jake wrote:I had an Omega TC in my PID'd Gaggia Classic espresso machine. They were nice people to do business with when it came time to replace the TC. Admittedly, I tend to use my hearing senses when roasting. Guess that's a throwback to roasting in the Behmor=:-)
.
The BT t/c won't replace listening for 1st C or 2nd C but it does give you realistic temp readings & a much better idea of what is happening in the bean mass. From what I'm seeing the HT sensor readings are for entertainment only. Being able to see exactly what is happening temp wise in the bean mass when you try to stretch the roast between 1st & 2nd is almost mandatory if you want to get the most out of your roasts.
Here's a couple pics of my ET t/c install & the fan mod. This is gen 1 on the fan mod as it is as yet untested in an actual roast. Might be more flow then I want so we'll have to see how it works.
The Omega t/c is potted in JB Weld inside the tube.
ET tc rear.jpg (75.26 KiB) Viewed 50607 times
Not a great pic but it does show the location.
ET tc front.jpg (58.32 KiB) Viewed 50607 times
Computer fan filter as per Randy G's mod using a #FF-120-S 120mm filter from Moddersmart. I removed material from the snap in cover by holding it up to the side of my bench grinder wheel. Holds the new filter in place securely.
fan mod.JPG (117.55 KiB) Viewed 50607 times
Original black filter cover added to restrict flow.
I've replaced the Omega 6" probe type BT t/c that I had mounted in the bean chute cover with another Omega XCIB-K163 t/c mounted below the stock HT temp sensor. These are ideal T/Cs for this application: http://www.omega.com/pptst/XCIB.html
Actual cost is $35 each not the $43 price shown at that link.
That's a nice installation. Your bean probe is in the same place as mine. I will be interested in hearing what your readings are during a roast. Depending on the bean, my probe shows between 395 and 405F for the start of first crack. Second kicks in between 445 and 455 although I seldom roast all the way to 2C except for espresso and some friends who think coffee should taste like Starbucks.
On a side note, now that I can get better control of my heater with the dimmer mod I am finding that I am shortening the time after the start of 1C for lighter roast, brewed coffee. For a 432°F roast I have found the flavors are better at 3 minutes than at 3:45, which is what I used to target. The longer stretch works well for darker roast espresso but really mutes the flavors on light roasts. Before the mod I never liked any roasts below 440° but now they are great!
Added an Ebay Staco 3PN2210 22A Variac & a UPM EM100 energy meter to the roasting stable earlier this summer. It certainly keeps you busy once you approach 1st crack controlling the B panel with the right hand while playing with the Variac control with the left & watching the two t/c readouts on the meter.
While I was on the HT site last night reading up on the "B", I was surprised to see the statement that the roaster performance is independent of voltage so no Variac required. That's news to me. I use a Variac, too, and as far as I can tell it definitely makes a difference.
Chas LM GS/3 & LaSpaziale Dream v 1.25 (US 120V) Mazzer Kony E, Customized Rocky Hottop P/B
I was using the energy meter to watch the voltage before buying the variac. Typically I was down in the 116-117v range under full power & I wanted to be able to run the HT at 120v throughout or dial it up or down as required. You can certainly roast without a variac but I really like having one now that I've tried it. The auction for my 2210 said that the previous owner replaced the power cord. They weren't kidding as it came with a huge 12/3 10' cord! I had no idea just how big & heavy these things are until I opened the box. I can see why they cost $600 new.
Time to wake this thread back up. My most recent HT mod detailed below:
I added new larger stirring fins replacing the 3 originals:
Larger fins.JPG (123.05 KiB) Viewed 50190 times
These improved distribution in the middle & rear but the front area needed some help:
New Fin Front.jpg (82.39 KiB) Viewed 50190 times
The extension in the front does a nice job of lifting/tossing the beans that always end up sliding around in the front cover. I've only done 2 227g FC+ roasts so far but the uniformity of the roast is greatly improved. The ejection time seems to be about the same as before with only one or 2 stragglers dropping out a few seconds later.
Last edited by JohnB on Fri May 07, 2010 11:53 am, edited 1 time in total.
These were my mods & I edited my post to show that more clearly. I do have several spare drums & could offer the modification on an exchange +$$ basis but no idea what I would charge at this point. If anyone is interested contact me off list.
How did you do the spot welding? Very clean job! Like every metal work that you did post here for that matter.
I almost pull the trigger on a Hottop B yesterday but it was out of stock. I may ask you to do a mod for me in the near future.
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
I welded the fins on using my mig. Not really a spot weld just nice, quick, hot welds from the rear that required very little clean up on the outside of the drum. I ran a business for many years doing show quality restorations of vintage & antique motorcycles dating back into the 1920s. Many required extensive metal work repairs or fabrication of NLA pieces. One of my "fun" hobbies is restoring mid 60's Alfa Romeo sports cars & believe me there is a lot of fabrication required as they were born to rust. My coffee equipment mods are pretty crude in comparison to my normal work but I appreciate the kind words.
I recently extended my t/cs further into the drum area so I could improve my readings. The Bt readings are now in line with the temps shown in the SM roast pictorial & my Et temp readings are much more accurate. Pics below show the new positions:
BT
My BT is about 1.5" from the front wall and still I think that I am getting temperature effect from the wall. I have ordered 4" probe T/C to get a little deeper in. Also, on my roaster the stirring vanes stop about 1" from the wall so the beans in contact with the wall tend to rotate less.
I guess that you had to trim off some of the last fins?
I am not comparing my roaster and yours directly as they are very different beast. I am just trying to learn generally.
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
I'll have to measure the actual depth into the drum but the biggest difference is that the t/c is now going into the deeper section of the bean mass. Look at the previous photos & you can see it was further up the side of the drum. Now it points right into the mass, which is deepest just up from bottom center & I believe the readings are much closer to actual bean surface temp.
I do not know how high a batch goes on the Hottop and how much beans there is at that point.
The location looks good. Certainly having the tip of the probe very near bottom center but not too close to the drum will help. Having a certain the probe length is also a plus to reduce the conduction through the probe to the drum wall.
Just out of curiosity. What is the drum diameter and the drum RPM for the Hottop?
Also did you hear anything back about the 1lb Hottop?
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
HT spins at 60rpm & drum is about 4" across. I've stopped asking about the 1lbr as Michael hasn't heard squat since last spring or so he says. Had to be in development winter 2010 when we spoke about it as he went into detail describing some of the features & improvements over prior versions of the HT. By the time it appears, if it ever does, everyone will own a Quest.
The Quest cannot handle 1 lb. It does best at 1/2 lb. I still believe that there is a market for a 1 lb. roaster that dumps the bean out to cool.
The Cafemino drum diameter is approx. 9 inch and the stock speed is 30 RPM. I changed the gear ratio to increase the drum speed to 60 RPM. It gets much better mixing of the beans and the roast is more even. I can also run the drum hotter without scorching. But that would not be applicable to the Hottop.
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
slo wrote:I still believe that there is a market for a 1 lb. roaster that dumps the bean out to cool.
Behmor and oven mits. $299.
Turns a 5lb bag ($ 50 bag) into 6 nice sized 13.3 oz roasts. That works out to almost exactly 3 shots per day (21 espressos per week) for each roast. I do the roasting every Sunday morning.
Frankly, considering the capacity and everything else you get for the price, I could care less about adding a little bean dumper. Just adapt your technique. The Behmor rules!
I was just making a statement of opinion on the 1lb roaster with external cooling. I think it would have benefits that would still attract buyers over the Quest.
I am not looking at another roaster. I am very happy with what I have. Popper for small batches and left overs and the Cafemino for larger batches.
I am sure that good roasts can be made with a Behmor. It is just that I really do not like opening an oven, reaching in and handling a burning hot piece of anything in a hurry. I am just too clumsy to even consider it.
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
slo wrote:I am sure that good roasts can be made with a Behmor. It is just that I really do not like opening an oven, reaching in and handling a burning hot piece of anything in a hurry. I am just too clumsy to even consider it.
Vivaldi II, Multiple (a collection really) Lever machines
Currently on deck grinders: Mythos and MXKR
Backup grinders: Robur, Major.
Toper Cafemino Electric and Poppery 1 roaster
