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Post by timwilde on Mar 27, 2014 2:03:33 GMT -5
For the most part, my DIY/converted roaster is complete, and looking at equipment that I need - a tempering machine seems next logical step. I've scanned the forums here, but havent really seen much in the way of ideas. I did find this on YouTube: www.youtube.com/watch?v=4MoCNodpBMEI think i'd like to incorporate some active cooling in some fashion to help assist with the cooling process. I'm curious if there are any pointers to other diy projects that would be sufficient. Looking to be able to temper a full batch out of the santha (max out at 10-12lbs, little extra for some buffer room) I'm thinking that with the growing availability and accuracy of temperature controllers, heating elements, and electronics in general this should be a relatively straightforward sort of thing. That being said, I have a few questions on the different tempering machine designs. The "wheel machines" such as Bakon's Choco TT vs the "half bowl" Chocovision Rev/x3210 What are the differences and pros/cons of each design? I personally kind of like the wheel machines and it appears those might be relatively easier to diy than the bowl machines but have zero experience with either. I will also likely have a need to incorporate some active cooling - I live in Arizona, and outside temps will be in the 110's soon enough, meaning inside temps will be in the 80's at the coldest. What, if any, existing machines have active cooling? I'm planning on scavenging a small window AC unit for this purpose. Basically looking for ideas to incorporate and some direction to move towards...any suggestions? BTW: I know I can temper in the Santha, I'm looking be able to empty the santha into the tempering machine and be able to clean it up while tempering is taking place and potentially get started on another batch. Any and all assistance is much appreciated. Thanks in advance
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Post by Ben on Mar 27, 2014 8:27:58 GMT -5
Cool project!
A couple thoughts:
I agree that the wheel machine would probably be easier to build.
I don't know of any smaller tempering machines--wheel or bowl--that use active cooling.
Consider using seed to avoid having to actively cool. Then you really only have to worry about heating, not cooling. (I actually assume you've already considered this but don't want to, but figured I'd mention it.)
Depending on how involved you want to get, consider building a water jacketed design. It could make it easier to control the temperature and avoid potential for scorching. I'm doing this with a project I'm working on--basically with the same idea as a Savage Bros. tempering machine.
For a wheel machine, you could use a food warmer with a hotel pan and then just build the wheel apparatus.
A potential problem with the wheel design when combined with active cooling is that it doesn't scrape the chocolate off the sides. I've actually wondered how the wheel machines in general handle this.
Good luck!
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Post by timwilde on Mar 27, 2014 11:32:04 GMT -5
Thanks for the support! I wouldn't mind walking out of this project with a much larger machine than is needed (now anyway, as I do plan on developing this into a small business), in order to incorporate the active cooling bit. I would use something that incorporates seed, however, I dont always have any on hand when I'm tempering up a batch. I *think* although cannot confirm, that the wheel machines use a constant agitation from the wheel turning and being scraped back down, plus active heating to prevent any under-tempering or overcrystalizing on the sides. Because it essentially is a half of a bowl, the constant up motion would create a current, which would keep the entire bowl moving, then there's the dropping back down by a fountain type effect as well. Those are my thoughts anyway; again, zero experience. The half bowls should be relatively easy as well, especially given the youtube video as a starting point; however, they seem overly large for what they do, the back half of the bowl in almost all of the designs I've seen seem to be wasted space. While I understand the need, the bowl spins and there's a constant scraping/agitation going on, it still seems wastefully large. Could I get a link to the savage bro's temperer? I'm hesitant on using water, only because this is diy, and water near a large quantity of chocolate just feels like it's asking for disaster to strike. Not only that, but water creates a thermal mass; which may hold temps better, but it's also slower to change them as well. I guess the good thing though about being here in summer; once it's in temper, it's highly unlikely to fall out of temper quickly The biggest concern for me and reason for the active cooling is because A/C units tend to only cool about 20-30 degrees at their best. Which is fine in most places, but we do regularly see 115+ or 120+ So assuming I've got a REALLY good AC and don't care about a $600 electric bill, I can at best hope for a 90 degree inside temp. Which might be perfect for working temps of chocolate, but kinda hard to get the low end into the 70's or even low 80's for that matter.
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Post by timwilde on Mar 27, 2014 13:57:47 GMT -5
hrmm, brainstorm idea....good/bad? If I make the water jacket completely sealed from the bowl (no chance of leaking into the bowl), would it possibly make sense to have a hot water tank and cold water tank; ala the way some water coolers do? With temp controls, I could control the temp of hot water, and then also control the temp of cold water; some sort of circulation pump to flow the water through the water jacket from both tanks, so as I need to cool, then it opens up and pumps cold (70-74F water) until chocolate reaches the desired temps, then closes off the cold water, and goes back to hot (85-91F water) to working temps? That system might be doable as I think about it, only need to worry about how to attach the agitator. While I didnt get a good look at the savage bros temperer, I did see an overview video on youtube that showed that the agitator is the thing that moves, not the drum/tank. Good, bad, ugly? BTW: I'm not opposed to spending money to get the job done, I am opposed to spending exorbitant amounts of money for what I see as relatively simple machines. I think with parts and fabrication, this might end up costing me maybe $1000, but if I walk away with a machine that I'd have to spend $5,000-$10,000 in order to buy, i see that as an awesome deal - plus I know that machine and where failpoints might be and how to fix them
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Post by Ben on Mar 27, 2014 17:58:01 GMT -5
I don't think the wheel machines scrape the sides very well if at all, and I don't think there's enough of a current to circulate all of the chocolate. Some of the existing ones use hotel pans, which I'd assume would need to be scraped manually. Otherwise, you're going to get some chocolate buildup. I assume the bowl-shaped ones do better with this, but I'd think they'd still need to be scraped occasionally. I don't know for sure, though, as I've never used one. Regarding seed, you could use a marble slab to cool a portion of the chocolate for seeding the rest. For the half-bowl, chocovision-style machines, what about moving the motor, fans, heater, etc. below the bowl to minimize footprint? I believe this is what the Hilliard's Little Dipper does. Here's the savage bros tempering machine: www.savagebros.com/p.27/50-lb-20-kg-table-top-chocolate-temperer-plc-touch-screen-chocolate-tempering.aspxThe way it works is that it hooks up to a cold water supply. During the cooling phase, it runs the water supply. It uses an internal heating element for the melting and warming phases. I'm working on a conche that works essentially this same way for temperature control. The only difference for mine is that I'll be using a tank of cold/room-temp water for cooling. For the savage, it takes almost no time to cool the water jacket water and only a few minutes to heat it. I think a heating element is simpler than a second tank for hot water.
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Post by timwilde on Mar 27, 2014 18:32:22 GMT -5
Yeah, definately going to have to mull over some design decisions. Ben: here's the Bakon video that kinda demo's the ChocoTT temperer. www.youtube.com/watch?v=Bi9_mg3ozvIBased on watching the video, it appears it's for high volume usage, which might be why scraping isnt needed? Not sure though. From the way it looks though, it looks like it just forms a current and agitates with both the wheel and scraper/fountain flow. Seeing as how it's fully metal, I imagine once reaching a temperature, it tries to hold that temp through heating - based on the design I think it's blowing hot air under/around the bowl, since they do show this as a melter as well. So while I can see the benefit of scrapping occasionally to keep the outter eges from getting too warm - I'm not sure that it would be due to overcrystalization. But again, just speaking from watching the video, no real experience with it to know precisely how they work. <Edit> You can see the current I'm talking about when the guy adds seed chocolate to the machine also forgot to mention: tabling on the marble slab is what I do now, normally. Which is fine right now, as I can keep my work area at around 70-72 degrees. It's in the 80's for the past week, so that's not too hard. However, if I need to cool down into the 70's for getting a proper seed, in the coming months, that's going to get more and more difficult to do when my work area is between 80 and 85 degrees or warmer. </Edit>
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Post by Ben on Mar 28, 2014 8:09:42 GMT -5
I'd guess that any tempering machine that uses forced air to control temperature is trying to maintain a set temperature in the chocolate as measured by a temperature probe somewhere stuck into the mass of chocolate. To do this, they cycle on and off the heater or cooling fan as necessary. If you have chocolate that is not being scraped off of the walls, you're going to get temperature differences between that and the overall mass. That could possibly introduce some problems like streaks and swirls on the finished bars. That being said, of course, they obviously work as lots of people use them successfully. It may be that my concerns are not that big of a deal in actual use, or that people just scrape the walls occasionally. Side note to the design of a tempering machine, but you may want to look further at better controlling your environment through a bigger/better a/c unit. Maybe one of the free-standing models with the hoses that vent out the window would work better, or just a model that is for a larger area than you're cooling. At least in Arizona you probably don't have to worry about humidity!
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Post by timwilde on Mar 28, 2014 12:16:00 GMT -5
Yeah, no humidity here! Worst we get is around 20-25% and even that's during our Monsoons. It's incredibly rare that we'll see actual humdity climb up beyond 50%. I've seen it get as high as 80% here, but that's happened once my almost 33 years of living here. In a residential setting, which is where I am, there's not much option. Residential AC units are designed to work with some efficiency, however, they can only fight so hard. While 80-85 sounds incredibly warm; you have no idea how chilly that feels after spending an afternoon in 110+ weather. Likewise, my work area is on the southfacing side of the house, with a western wall. With 3 windows, the largest window area is on south side, with a fairly large window next to it on the west wall, and yet another smaller one in the kitchen area. This would be the hottest part of the house, with the most direct sun. Better AC units than what I have are expensive (last I priced was $16,000) Powerful enough to keep a 70-75 room temp might be a little more. The other aspect is that I'd be blowing $600+/month on electricity just to maintain that temp. Cold cabinets, tempering machine with active cooling, and the like is what I'll need to utilize to be efficient. Industrial chillers are utilized for almost all commercial spaces, and if I get to that point where I'm moving into a shop I'll be set. In the meantime, fighting the sun against those windows, even though I'm in an energy efficient, newer build house, makes for a hard time keeping temps in the 70-75 range for chocolate making. Might be why I rarely find any chocolate shops or chocolatiers here locally. I guess the best thing that I can say about my summer environment, once I do have tempered chocolate; I'll have plenty of time to work with it. Well, I'm roping in a couple of engineering buddies to help me with this design. I think seeing the different models out there, Savage Bros, Bakon ChocoTT, JKV30, Chocovision, I think we can come up with something cool, and simple. It may end up on a cart to house the cooling, but should be doable.
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Post by timwilde on Jul 22, 2014 2:46:30 GMT -5
Hi again! Wanted to post a slight update as I've officially taken a break for the summer. I got an order for truffles and molded chocolates for a wedding back in June just as the outside temps hit the low 100's. Tempering manually was an absolute nightmare - I found out the hard way that A/C units only blow one temp of air; really cold. My kitchen/work area has an A/C vent directly above the work area. This ice cold air chilled the chocolate very fast and gave me about 1-2 minutes of operating window before it would overcrystalize to the point I'd need to temper again. I tried closing off the vent directly near the work area, but that just raised the temperature of the kitchen area to the point it was next to impossible to get cooled to the correct seed temp. As a result, batch 1 of 200 truffles were not properly tempered, which was made usable by the coating - dipped center and then rolled in cookie coating. Not proud of that workaround, but it delivered an ok result. The 2nd batch of truffles weren't so easy. Essentially, I needed to wait for the sun to go down, chill the kitchen to operating temps (72-75 degrees) and work quickly - this worked perfectly, but required I do most of the work after midnight. Which, frankly, isnt very conducive to maintaining my day job I may end up by having to experiment with commercial tempering machines to get a feel for what they do and how they work before DIY'ing a machine for use in these conditions. One thing that did stick with me though, I found a homebrew beer fermenter that was actively cooled, which may have some good use converted over as a tempering machine. The design was basically a large fermenting kettle (10 gallons) which had a copper coil tightly wound on the outside of the kettle, this was then insulated and wrapped with sheet aluminum. The system pumped propelene glycol through the copper tubing through an ac unit which cooled the PG. There was a temperature probe connected to temp controller, which was able to keep temperatures accurate to within 1 degree. I think converting this design to incorporate a secondary coil pushing warmed PG may be a good way to go, but still researching if that will be feasible to build, and would need to figure out how to agitate the chocolate in the kettle. This design looks like it will end up by being large, but I think I can fit the heating/cooling tanks and equipment onto a wheeled cart that may have a relatively small footprint.
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Post by chadmart1076 on Aug 12, 2014 11:56:09 GMT -5
After failing at tempering a batch of milk chocolate very badly, I started looking at tempering machines. (I just need to retemper, but it is frustrating tempering by hand and then having that white bloom start to appear.) Anyway, I was all set to buy the Chocovision mini-rev, but realized (thankfully) that it doesn't have a temp. readout. It just tempers based on the setting you choose (white, milk, dark). I want something that I can not only see the temperature, but control it as well. I like the ACMC machine, but I really don't want to jump from $300 to $800. I found my answer in some home-microbrewing forums... www.amazon.com/gp/product/B008KVCPH2/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1This is a temperature control unit which activates one of two circuits depending on if your measured temp is above or below the desired temp. (heating and cooling in other words). In the microbrew world the example is that their product is in a fridge, and if the temp is above what they want, the fridge is turned on. If the temp is too low, the fridge turns off and a heating element (easiest example is a hair dryer) is turned on. Inspiration struck! I am going to build a box. Set into the outside of the box will be an aluminum bowl with a temp. probe threaded into the bottom of the bowl. Also set into the outside of the box will be the temperature controller. Inside the box will contain 2 light bulbs as my heating elements (a-la the ACMC tempering machine). When the temp is too low the lights will turn on, warming the bottom of the bowl. Also in the box will be two computer cooling fans, one pulling air in, the other on the opposite wall, pushing air out. This isn't a refrigerated method of cooling, but from what I've read, you don't want to cool or heat too rapidly while tempering anyway. The downside is that at this time I won't have a way of automatically stirring the chocolate, but at least I can accurately control the temperature and stir by hand. However, over time I might be able to incorporate a motor to spin the bowl, a scraper, etc... I'm thinking that spinning the bowl might be a good idea even without the scraper so that the heat distribution from the bulbs is more consistent across the whole bowl. I could also go with four lesser-wattage bulbs or just the two bulbs directly under the bowl. I am a little worried about scorching the chocolate using light bulbs as my heat source, but I think playing with the distance from the bulbs to the bowl should help to alleviate that issue. In any case, I'll be sure to constantly stir the chocolate as long as the bulbs are on. Any thoughts? Update: I had a thought... instead of light bulbs, I can use the heating element from a hair dryer. I will align the fans and create a circular path inside the box so that one fan circulates air within the box, the other fan vents air out of the box. When the chocolate needs to increase temperature, the heating element will be on, as will the circulation fan. When the chocolate needs to decrease temperature, the heating element will turn off, the circulation fan will remain on, and the vent fan will turn on, venting the warm air out of the box.
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Post by chadmart1076 on Aug 18, 2014 11:18:31 GMT -5
I began construction of my temperature controlled bowl this weekend. My first attempts at finding the remaining materials I needed were met with resistance. My goal is to build a decent piece of equipment (i.e. not have it looking too pieced together) but still remain relatively cheap.
My enclosure is a PVC electrical box from Lowes. It is 12"x12"x6". It is a little small, but in the end I think it will do what I need it to.
Since I am using PC fans for circulation I found that I needed to transform the power from the temp. controller (120V) down to 12V, so I found a couple of transformers at Radio Shack. Ideally I could have cannibalized some power adapters from old electronics, but the only "junk" one I found was 6V not 12. I recently got rid of my "junk wire" box at a yard sale. D'oh!
This left the heat source. I bought the cheapest hair dryer at Wal Mart and took it apart. after separating the motor from the heating coils I plugged it in to check out how it worked. Two issues came to light. One, the thing gets incredibly hot, particularly without a fan pushing cool air over it. It has a safety feature built in that pops the circuit if it gets too hot. Then I almost set my house on fire when I shorted the thing accidentally. Nix the hair dryer and back to bulbs. I am still going to use the fans to circulate/vent. The ACMC tempering machine uses two-100W bulbs, but all I think I can fit in this box is a single 60 watt bulb. It might take a while to melt my chocolate.
Anyway, I broke out the Dremmel last night and have all of my holes cut in the enclosure. I need to get some longer screws and such to finish putting it together. I anticipate it being done tonight or tomorrow night.
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gap
Apprentice
Posts: 390
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Post by gap on Aug 18, 2014 16:38:19 GMT -5
Sounds interesting - post some pics when you have a chance
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Post by chadmart1076 on Dec 29, 2014 18:49:45 GMT -5
I got the thing put together and the controller didn't work properly. So I returned it and had a replacement sent. I finally got around to hooking it up and it doesn't seem to work either. Based on the readout it is working fine, but none of the devices are turning on. I'm thinking maybe the wire I used was a poor choice. I'm going to replace it and see if that works. I also need to get a meter to make sure that the controller is putting out power to the right circuits.
In any case I might ditch this effort in favor of a new option. See my Sous Vide post for that option! I'm very excited about this one!
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