| |
Main
Date: 19 Feb 2007 18:43:52
From: Jonathan Thiessen
Subject: Home roasting thoughts
|
Salutations, I was thinking, and I've come up with an idea. Whether it's a good [or original] idea, or not, I'm not sure. The plan is to use a portable induction cooktop with... a pot. The idea is also to have an overhead electric motor driving a mixing blade, and also to run the cooktop through a variac which is magically controlled by a fancy temperature controller like the nice Fuji ones. One of the very nice things about induction cooktops is that they are rather responsive [much like gas burners]. In my thinking though, this sort of responsiveness doesn't mean much if it can't be controlled smoothly [analogue-like, or at least multi-step]. I've never actually used an induction cooktop before, but we have a halogen one, and the most annoying aspect of it is that the different temp settings are realized by it turning off, and on occasionally which yields a most inconsistent/erratic temp that is useless for cooking anything but water. I wouldn't want the same sort of issue with my coffee roasting apparatus. But maybe I'm off on this one **shrugs**. My concerns are: 1. Running an electric motor close to an induction cooktop. Is this a problem? [Both being magnetic devices, and all] 2. Are there temp controllers that are "analogue", or are they all "digital" in design? That is to say, will they output at a constant voltage, or off; or can they output smoothly over a range [Lets say you're ramping up, but going to fast. Instead of letting it go until it's over temp, it should give a decrease in voltage signaling that the heater should give a reduced output, and thus avoiding overshooting, and undershooting]. Should I even be concerned with this? Will it make a difference? Am I better off to just control a relay with the temp controller, rather than bothering with smooth temp transition? 3. Are there variacs that can be controlled via some control voltage. In other words, can we somehow scale the control voltage output from the temp controller up to the 0-120VAC sort of range. 4. Is it ok/safe to run induction cooktops at a reduced voltage? Should I look for a purely analogue cooktop so that I can set it full-bore, and let the variac do it's thing? [That is, will running a digitally controlled unit on a variac screw it up?]. 5. Is this all-round just a really bad idea? I mean... I really quite like it conceptually so long as it's possible, and [economically] feasible. What are your thoughts? Thank you for your time. Have a good one ;) //jonathan
|
|
| |
Date: 22 Feb 2007 10:59:28
From:
Subject: Re: Home roasting thoughts
|
I've been overly-sensitive ever since celebrating Washington's birthday on some day other than the 22nd. # : o ) tin On Feb 21, 4:34 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com > wrote: > tin, you and I have both posted together on alt.coffee and other lists > over the years, and I highly regard your inventive and creative skills. = On > alt.coffee I have never gotten into any of the shenanigans that many have, > with slurs, name calling and outright insults. I try 'once' to get just a > little bit feisty and now I'm in trouble. > Just give me this one jab, please :::::grin::::::. > Go ahead, call me a bean head or something so we can be even. > -- > ********************* > Ed Needham=AE > "to absurdity and beyond!"http://www.homeroaster.com > (include [FRIEND] in subject line to get through my SPAM filters) > ********************* > > <coffeeem...@gmail.com> wrote in message > > news:1172036614.947980.107230@q2g2000cwa.googlegroups.com... > Fair enough. Nothing here to argue with. But it's quite a jump to > characterize my "personal criteria" (either generally or specifically) > as "rules [that] need to be followed stringently" and "grunting > through a list of rules." IMO, one doesn't have to choose between the > criteria that I stated and giving full reign to inspiration or > invention. Rules may get in the way of invention, but knowledge > generally doesn't. > > tin (Heat + beans =3D roast. All the rest is commentary) > > On Feb 20, 8:17 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com> wrote: > > > My reply was not an insult but rather a commentary. > > > I've found that rules just get in the way of invention. Maybe at a > > corporate level rules need to be followed stringently, but as a small, > > home > > inventor, rules impede progress. I've had several firsts and they have > > all > > come from inspiration rather than grunting through a list of rules to > > follow. Generally they have been given birth by breaking established > > rules > > or going places where rules have not been devised. > > > Thomas Edison once said, > > "Hell, there are no rules here-- we're trying to accomplish something." > > > I think he was on to something. > > -- > > ********************* > > Ed Needham=AE > > "to absurdity and beyond!"http://www.homeroaster.com > > (include [FRIEND] in subject line to get through my SPAM filters) > > ********************* > > > <coffeeem...@gmail.com> wrote in message > > >news:1172025742.438605.11650@j27g2000cwj.googlegroups.com... > > > > Ah, the oft-used Needham "(g)." Meaning, "insult intended." > > > > I don't make procedures for the government, but I don't categorically > > > reject fiscal, safety, and performance criteria even if they originate > > > from the the govt. Likewise, I don't valorize franken-roasters > > > unless they actually accomplish something that's more parsimonious > > > than a Hottop, dogbowl, variac'd popper, etc. So I offered my > > > "personal criteria" along with the caveat of "it's worth trying > > > anything on little more than a hunch" (which seemed only fitting > > > coming from someone who stumbled onto HG/DB roasting barely before he > > > knew which end of the bean was up). > > > > So are there any of the criteria that you disagree with? Any others > > > that you'd offer? > > > (f)
|
| |
Date: 20 Feb 2007 21:43:35
From:
Subject: Re: Home roasting thoughts
|
Fair enough. Nothing here to argue with. But it's quite a jump to characterize my "personal criteria" (either generally or specifically) as "rules [that] need to be followed stringently" and "grunting through a list of rules." IMO, one doesn't have to choose between the criteria that I stated and giving full reign to inspiration or invention. Rules may get in the way of invention, but knowledge generally doesn't. tin (Heat + beans =3D roast. All the rest is commentary) On Feb 20, 8:17 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com > wrote: > My reply was not an insult but rather a commentary. > > I've found that rules just get in the way of invention. Maybe at a > corporate level rules need to be followed stringently, but as a small, ho= me > inventor, rules impede progress. I've had several firsts and they have a= ll > come from inspiration rather than grunting through a list of rules to > follow. Generally they have been given birth by breaking established ru= les > or going places where rules have not been devised. > > Thomas Edison once said, > "Hell, there are no rules here-- we're trying to accomplish something." > > I think he was on to something. > -- > ********************* > Ed Needham=AE > "to absurdity and beyond!"http://www.homeroaster.com > (include [FRIEND] in subject line to get through my SPAM filters) > ********************* > > <coffeeem...@gmail.com> wrote in message > > news:1172025742.438605.11650@j27g2000cwj.googlegroups.com... > > > Ah, the oft-used Needham "(g)." Meaning, "insult intended." > > > I don't make procedures for the government, but I don't categorically > > reject fiscal, safety, and performance criteria even if they originate > > from the the govt. Likewise, I don't valorize franken-roasters > > unless they actually accomplish something that's more parsimonious > > than a Hottop, dogbowl, variac'd popper, etc. So I offered my > > "personal criteria" along with the caveat of "it's worth trying > > anything on little more than a hunch" (which seemed only fitting > > coming from someone who stumbled onto HG/DB roasting barely before he > > knew which end of the bean was up). > > > So are there any of the criteria that you disagree with? Any others > > that you'd offer? > > (f)
|
| | |
Date: 21 Feb 2007 19:34:54
From: Ed Needham
Subject: Re: Home roasting thoughts
|
tin, you and I have both posted together on alt.coffee and other lists over the years, and I highly regard your inventive and creative skills. On alt.coffee I have never gotten into any of the shenanigans that many have, with slurs, name calling and outright insults. I try 'once' to get just a little bit feisty and now I'm in trouble. Just give me this one jab, please :::::grin::::::. Go ahead, call me a bean head or something so we can be even. -- ********************* Ed Needham® "to absurdity and beyond!" http://www.homeroaster.com (include [FRIEND] in subject line to get through my SPAM filters) ********************* <coffeeemail@gmail.com > wrote in message news:1172036614.947980.107230@q2g2000cwa.googlegroups.com... Fair enough. Nothing here to argue with. But it's quite a jump to characterize my "personal criteria" (either generally or specifically) as "rules [that] need to be followed stringently" and "grunting through a list of rules." IMO, one doesn't have to choose between the criteria that I stated and giving full reign to inspiration or invention. Rules may get in the way of invention, but knowledge generally doesn't. tin (Heat + beans = roast. All the rest is commentary) On Feb 20, 8:17 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com > wrote: > My reply was not an insult but rather a commentary. > > I've found that rules just get in the way of invention. Maybe at a > corporate level rules need to be followed stringently, but as a small, > home > inventor, rules impede progress. I've had several firsts and they have > all > come from inspiration rather than grunting through a list of rules to > follow. Generally they have been given birth by breaking established > rules > or going places where rules have not been devised. > > Thomas Edison once said, > "Hell, there are no rules here-- we're trying to accomplish something." > > I think he was on to something. > -- > ********************* > Ed Needham® > "to absurdity and beyond!"http://www.homeroaster.com > (include [FRIEND] in subject line to get through my SPAM filters) > ********************* > > <coffeeem...@gmail.com> wrote in message > > news:1172025742.438605.11650@j27g2000cwj.googlegroups.com... > > > Ah, the oft-used Needham "(g)." Meaning, "insult intended." > > > I don't make procedures for the government, but I don't categorically > > reject fiscal, safety, and performance criteria even if they originate > > from the the govt. Likewise, I don't valorize franken-roasters > > unless they actually accomplish something that's more parsimonious > > than a Hottop, dogbowl, variac'd popper, etc. So I offered my > > "personal criteria" along with the caveat of "it's worth trying > > anything on little more than a hunch" (which seemed only fitting > > coming from someone who stumbled onto HG/DB roasting barely before he > > knew which end of the bean was up). > > > So are there any of the criteria that you disagree with? Any others > > that you'd offer? > > (f)
|
| |
Date: 20 Feb 2007 20:53:50
From: rasqual
Subject: Re: Home roasting thoughts
|
On Feb 20, 3:19 pm, Jonathan Thiessen <jjthies...@student.math.uwaterloo.ca > wrote: > Oh yeah... I forgot to say, [with respect to the espresso machine] if > one is going to control the piston via some on device controller, or a > standalone computer, you might as well have precise control over the > brewing temps too since water is heated on a per shot basis. What follows is NOT a mindless lampoon. How about using a variation on MRI scanning to measure the water temperature EXTREMELY precisely? What's great is that it would allow for measuring the amount of heat present in the entire water volume, rather than counting on some geographic locus of median reliability on the surface of something. Perhaps the best thing would be to contrive an analog method -- perhaps using Nitinol valves -- of automatically controlling backpressure to regulate thermal transfer to a flowing volume of water. Envision a showerhead with each of hundreds of small holes being heated and controlled independently, easily within a tenth of a degree. Each orifice would be an instance of nanotech in action. In a bizarre sense, I'm advocating reliance on high tech to implement utter low-tech -- precise analog regulation, rather than positive control in a digital sense. In some sense, I'm advocating the nano equivalent of the centrifugal governors on old steam engines. ;-) Like I said, not mindless lampoon. Someone just told me, "show them you're nuts," so I did. ;-) - Scott
|
| | |
Date: 21 Feb 2007 02:16:53
From: Jonathan Thiessen
Subject: Re: Home roasting thoughts
|
Good stuff :) If I ever need ideas I now know who to come to :P But yeah, seriously, I believe that my espresso machine idea would make for an awesome reference machine -- not at all practical, but who cares? It really would be industrial/lab equipment. Nothing quite like it that I know of anyway *-) Who knows, maybe it truly is/will be practical **shrugs** I'll make sure to tell you guys when I'm done :P rasqual wrote: > On Feb 20, 3:19 pm, Jonathan Thiessen > <jjthies...@student.math.uwaterloo.ca> wrote: >> Oh yeah... I forgot to say, [with respect to the espresso machine] if >> one is going to control the piston via some on device controller, or a >> standalone computer, you might as well have precise control over the >> brewing temps too since water is heated on a per shot basis. > > What follows is NOT a mindless lampoon. > > How about using a variation on MRI scanning to measure the water > temperature EXTREMELY precisely? What's great is that it would allow > for measuring the amount of heat present in the entire water volume, > rather than counting on some geographic locus of median reliability on > the surface of something. > > Perhaps the best thing would be to contrive an analog method -- > perhaps using Nitinol valves -- of automatically controlling > backpressure to regulate thermal transfer to a flowing volume of > water. Envision a showerhead with each of hundreds of small holes > being heated and controlled independently, easily within a tenth of a > degree. Each orifice would be an instance of nanotech in action. > > In a bizarre sense, I'm advocating reliance on high tech to implement > utter low-tech -- precise analog regulation, rather than positive > control in a digital sense. In some sense, I'm advocating the nano > equivalent of the centrifugal governors on old steam engines. ;-) > > Like I said, not mindless lampoon. Someone just told me, "show them > you're nuts," so I did. ;-) > > - Scott >
|
| | |
Date: 20 Feb 2007 21:45:46
From: Johnny
Subject: Re: Home roasting thoughts
|
"rasqual" <scott.quardt@gmail.com > wrote in message news:1172033630.545792.35080@v45g2000cwv.googlegroups.com... > On Feb 20, 3:19 pm, Jonathan Thiessen > <jjthies...@student.math.uwaterloo.ca> wrote: > > Oh yeah... I forgot to say, [with respect to the espresso machine] if > > one is going to control the piston via some on device controller, or a > > standalone computer, you might as well have precise control over the > > brewing temps too since water is heated on a per shot basis. > > What follows is NOT a mindless lampoon. > > How about using a variation on MRI scanning to measure the water > temperature EXTREMELY precisely? What's great is that it would allow > for measuring the amount of heat present in the entire water volume, > rather than counting on some geographic locus of median reliability on > the surface of something. isn't that the way a pressure sensor works? averaging out the pressure based on the overall heat present.
|
| | | |
Date: 21 Feb 2007 02:01:44
From: Jonathan Thiessen
Subject: Re: Home roasting thoughts
|
Pressure sensors should work on the basis of force measurement of some sort, me thinks [ie a spring [at least in the case of old-school gauges]]. I personally don't know of other methods, but of course, I'm not entirely infallible :P As long as you don't need your gauges/sensors anywhere near as fast/responsive as the speed of sound in whatever fluid you're measuring the pressure of; or, you need the pressure at various depths [which you could actually calc by hand using only one reference pressure], you should be ok with just one gauge/sensor. Pressure really is just force averaged over an area. I could be misunderstanding what you're saying though. Given the right restraints on your system, you could indirectly calculate the pressure of your system as a function of internal energy, or something like that, but it'd be pretty tech. Of course, if we're going to use an MRI somehow, we might as well. Johnny wrote: > "rasqual" <scott.quardt@gmail.com> wrote in message > news:1172033630.545792.35080@v45g2000cwv.googlegroups.com... >> On Feb 20, 3:19 pm, Jonathan Thiessen >> <jjthies...@student.math.uwaterloo.ca> wrote: >>> Oh yeah... I forgot to say, [with respect to the espresso machine] if >>> one is going to control the piston via some on device controller, or a >>> standalone computer, you might as well have precise control over the >>> brewing temps too since water is heated on a per shot basis. >> What follows is NOT a mindless lampoon. >> >> How about using a variation on MRI scanning to measure the water >> temperature EXTREMELY precisely? What's great is that it would allow >> for measuring the amount of heat present in the entire water volume, >> rather than counting on some geographic locus of median reliability on >> the surface of something. > > isn't that the way a pressure sensor works? averaging out the pressure based > on the overall heat present. > > >
|
| |
Date: 20 Feb 2007 18:42:22
From:
Subject: Re: Home roasting thoughts
|
Ah, the oft-used Needham "(g)." Meaning, "insult intended." I don't make procedures for the government, but I don't categorically reject fiscal, safety, and performance criteria even if they originate from the the govt. Likewise, I don't valorize franken-roasters unless they actually accomplish something that's more parsimonious than a Hottop, dogbowl, variac'd popper, etc. So I offered my "personal criteria" along with the caveat of "it's worth trying anything on little more than a hunch" (which seemed only fitting coming from someone who stumbled onto HG/DB roasting barely before he knew which end of the bean was up). So are there any of the criteria that you disagree with? Any others that you'd offer? (f) On Feb 20, 4:23 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com > wrote: > You work for the government policies and procedures office, right? > (g) > > <coffeeem...@gmail.com> wrote in message > > news:1171993409.710749.112250@h3g2000cwc.googlegroups.com... > > > For starters, here are some personal criteria I'd have to satisfy > > before embartking on complex invention. Not inclusive or necessarily > > the order of importance: > > 1. I'd have to be an excellent and experienced cupper. Not just I- > > know-what-I-like, but having a wide range of controlled and confirmed > > experience. Otherwise, how could I trust any of my findings along the > > way? How could I sensibly draw from the experiences of a far-flung > > community of other experts? > > 2. I'd have to know what particular aspects of current technology I > > want to improve upon. This would require some experience with a > > variety of current roasting methods. Simply demonstrating that I > > could make a decent roast happen would not not be enough. I'd want to > > target a batch size range; not build the unit and then see how much it > > could roast. OTOH, if the materials and assembly were handy and cheap, > > it's worth trying anything on little more than a hunch. > > 3. Convenient strorage, aestheticly pleasing, and robustly built > > should not be afterthoughts, but considerations from the very > > begining. These account for much of the cost of off-the-shelf quality > > roasters. So is the goal to build a cheaper Hottop or Probat with the > > minor inconveniences of a tangle of exposed wires, corners that singe > > and rip flesh, tripped breakers, and which you operate from the floor > > of an unheated garage? > > tin
|
| | |
Date: 20 Feb 2007 23:17:51
From: Ed Needham
Subject: Re: Home roasting thoughts
|
My reply was not an insult but rather a commentary. I've found that rules just get in the way of invention. Maybe at a corporate level rules need to be followed stringently, but as a small, home inventor, rules impede progress. I've had several firsts and they have all come from inspiration rather than grunting through a list of rules to follow. Generally they have been given birth by breaking established rules or going places where rules have not been devised. Thomas Edison once said, "Hell, there are no rules here-- we're trying to accomplish something." I think he was on to something. -- ********************* Ed Needham® "to absurdity and beyond!" http://www.homeroaster.com (include [FRIEND] in subject line to get through my SPAM filters) ********************* <coffeeemail@gmail.com > wrote in message news:1172025742.438605.11650@j27g2000cwj.googlegroups.com... > Ah, the oft-used Needham "(g)." Meaning, "insult intended." > > I don't make procedures for the government, but I don't categorically > reject fiscal, safety, and performance criteria even if they originate > from the the govt. Likewise, I don't valorize franken-roasters > unless they actually accomplish something that's more parsimonious > than a Hottop, dogbowl, variac'd popper, etc. So I offered my > "personal criteria" along with the caveat of "it's worth trying > anything on little more than a hunch" (which seemed only fitting > coming from someone who stumbled onto HG/DB roasting barely before he > knew which end of the bean was up). > > So are there any of the criteria that you disagree with? Any others > that you'd offer? > (f)
|
| | |
Date: 20 Feb 2007 23:11:03
From: Ed Needham
Subject: Re: Home roasting thoughts
|
I've found that rules just get in the way of invention. Maybe at a corporate level rules need to be followed stringently, but as a small, home inventor, rules just get in the way. I've had several firsts and they have all come from inspiration rather than grunting through a list of rules to follow. Generally they have been given birth by breaking established rules or going places where rules have not been devised. Thomas Edison once said, "Hell, there are no rules here-- we're trying to accomplish something." I think he was on to something. -- ********************* Ed Needham® "to absurdity and beyond!" http://www.homeroaster.com (include [FRIEND] in subject line to get through my SPAM filters) ********************* <coffeeemail@gmail.com > wrote in message news:1172025742.438605.11650@j27g2000cwj.googlegroups.com... > Ah, the oft-used Needham "(g)." Meaning, "insult intended." > > I don't make procedures for the government, but I don't categorically > reject fiscal, safety, and performance criteria even if they originate > from the the govt. Likewise, I don't valorize franken-roasters > unless they actually accomplish something that's more parsimonious > than a Hottop, dogbowl, variac'd popper, etc. So I offered my > "personal criteria" along with the caveat of "it's worth trying > anything on little more than a hunch" (which seemed only fitting > coming from someone who stumbled onto HG/DB roasting barely before he > knew which end of the bean was up). > > So are there any of the criteria that you disagree with? Any others > that you'd offer? > (f) > > On Feb 20, 4:23 pm, "Ed Needham" <e...@NOSPAMhomeroaster.com> wrote: >> You work for the government policies and procedures office, right? >> (g)
|
| |
Date: 20 Feb 2007 09:51:48
From: Calvin
Subject: Re: Home roasting thoughts
|
On Feb 19, 5:43 pm, Jonathan Thiessen <jjthies...@student.math.uwaterloo.ca > wrote: > Salutations, > > I was thinking, and I've come up with an idea. Whether it's a good [or > original] idea, or not, I'm not sure. The plan is to use a portable > induction cooktop with... a pot. The idea is also to have an overhead > electric motor driving a mixing blade, and also to run the cooktop > through a variac which is magically controlled by a fancy temperature > controller like the nice Fuji ones. One of the very nice things about > induction cooktops is that they are rather responsive [much like gas > burners]. In my thinking though, this sort of responsiveness doesn't > mean much if it can't be controlled smoothly [analogue-like, or at least > multi-step]. I've never actually used an induction cooktop before, but > we have a halogen one, and the most annoying aspect of it is that the > different temp settings are realized by it turning off, and on > occasionally which yields a most inconsistent/erratic temp that is > useless for cooking anything but water. I wouldn't want the same sort of > issue with my coffee roasting apparatus. But maybe I'm off on this one > **shrugs**. > > My concerns are: > 1. Running an electric motor close to an induction cooktop. Is this a > problem? [Both being magnetic devices, and all] > 2. Are there temp controllers that are "analogue", or are they all > "digital" in design? That is to say, will they output at a constant > voltage, or off; or can they output smoothly over a range [Lets say > you're ramping up, but going to fast. Instead of letting it go until > it's over temp, it should give a decrease in voltage signaling that the > heater should give a reduced output, and thus avoiding overshooting, and > undershooting]. Should I even be concerned with this? Will it make a > difference? Am I better off to just control a relay with the temp > controller, rather than bothering with smooth temp transition? > 3. Are there variacs that can be controlled via some control voltage. In > other words, can we somehow scale the control voltage output from the > temp controller up to the 0-120VAC sort of range. > 4. Is it ok/safe to run induction cooktops at a reduced voltage? Should > I look for a purely analogue cooktop so that I can set it full-bore, and > let the variac do it's thing? [That is, will running a digitally > controlled unit on a variac screw it up?]. > 5. Is this all-round just a really bad idea? I mean... I really quite > like it conceptually so long as it's possible, and [economically] > feasible. What are your thoughts? > > Thank you for your time. > Have a good one ;) > //jonathan I don't know if an inductive cooktop can be run duty cycle and if you will be able to find an SSR that will put up with the abuse. It would definitely be cheaper and easier to use a resistive element like the standalone ones you can get for $15 at any department store. To go the variac route you would need to build a coupling and mount for a servo motor and then build your own temp sensor and PID to drive it; stock PIDs can read a thermocouple and drive an SSR already. It sounds like you are trying to build an automated pan-roaster. I have my doubts that a PID would ever be able to manage such a chaotic and massive system. You would probably need to sample over such a large time frame - tens of seconds - and react so slowly that you would not have the fine control that you are pursuing in the first place. It's a long trip from the range to the bean mass. >From my experience in pan roasting the most important factor is bean movement. You MUST keep the beans in motion in both dimensions. You ability to roast in a controlled way will be a result of finding the right balance between heat transfer from the pot (surface area), charge size (total mass to heat), and stirring (getting that heat into all surfaces of all the beans the same). Good luck and don't let the nay-sayers like me keep you from experimenting.
|
| | |
Date: 20 Feb 2007 16:05:37
From: Jonathan Thiessen
Subject: Re: Home roasting thoughts
|
I'm not sure if I'll actually get to experimenting for a couple months yet [when I get back home for the summer], so for right now I'm just trying to toss some ideas around [Both in my head, and out to people with better roasting and electrical/PID experience]. My original thought was that a drum would be better, but I like the idea of inductive cooking [roasting in this case], and I couldn't really think of anyway of keeping with both. In my thinking, gas/propane really would be the best method, however, sort of that, I would think it best to make the heating as direct as possible so as to avoid the issues of thermal mass affecting control [inductive, light, microwave?]. One issue with microwave is that it excites water [any moisture?] within, rather than being radiant [heat wise]. Which reminds me... I also have an idea for an espresso machine, and I think it'd be awesome if ever I did actually pursue it [maybe one of these days when I'm back at home :)]. But yeah... The idea is to make the machine as thermally insulated/non-conducting as possible, and to dose water into a chamber [expressly for you :P] where it is heated using microwaves, and then forced through the coffee puck by a PLC'd hydraulic piston. I believe this would lead to the ultimate extraction given the instant on/instant off thermal stability, and controllable [read smooth rampable] flow rate/pressure. It would be a _relatively_ simple design, and it would offer all the advantages of a piston/lever machine, but it would be completely controllable/consistent/ever predictable. The only possible disadvantage that I can think of is maybe cost [And I suppose that if you really want to make milk beverages, then you'll have to look elsewhere to steam/froth... Oh, and I suppose it would take a bit longer to make a shot given that water is heated on a per shot basis [Although the nice thing is that idle draw - >0W], so make that three disadvantages]. Calvin wrote: > On Feb 19, 5:43 pm, Jonathan Thiessen > <jjthies...@student.math.uwaterloo.ca> wrote: >> Salutations, >> >> I was thinking, and I've come up with an idea. Whether it's a good [or >> original] idea, or not, I'm not sure. The plan is to use a portable >> induction cooktop with... a pot. The idea is also to have an overhead >> electric motor driving a mixing blade, and also to run the cooktop >> through a variac which is magically controlled by a fancy temperature >> controller like the nice Fuji ones. One of the very nice things about >> induction cooktops is that they are rather responsive [much like gas >> burners]. In my thinking though, this sort of responsiveness doesn't >> mean much if it can't be controlled smoothly [analogue-like, or at least >> multi-step]. I've never actually used an induction cooktop before, but >> we have a halogen one, and the most annoying aspect of it is that the >> different temp settings are realized by it turning off, and on >> occasionally which yields a most inconsistent/erratic temp that is >> useless for cooking anything but water. I wouldn't want the same sort of >> issue with my coffee roasting apparatus. But maybe I'm off on this one >> **shrugs**. >> >> My concerns are: >> 1. Running an electric motor close to an induction cooktop. Is this a >> problem? [Both being magnetic devices, and all] >> 2. Are there temp controllers that are "analogue", or are they all >> "digital" in design? That is to say, will they output at a constant >> voltage, or off; or can they output smoothly over a range [Lets say >> you're ramping up, but going to fast. Instead of letting it go until >> it's over temp, it should give a decrease in voltage signaling that the >> heater should give a reduced output, and thus avoiding overshooting, and >> undershooting]. Should I even be concerned with this? Will it make a >> difference? Am I better off to just control a relay with the temp >> controller, rather than bothering with smooth temp transition? >> 3. Are there variacs that can be controlled via some control voltage. In >> other words, can we somehow scale the control voltage output from the >> temp controller up to the 0-120VAC sort of range. >> 4. Is it ok/safe to run induction cooktops at a reduced voltage? Should >> I look for a purely analogue cooktop so that I can set it full-bore, and >> let the variac do it's thing? [That is, will running a digitally >> controlled unit on a variac screw it up?]. >> 5. Is this all-round just a really bad idea? I mean... I really quite >> like it conceptually so long as it's possible, and [economically] >> feasible. What are your thoughts? >> >> Thank you for your time. >> Have a good one ;) >> //jonathan > > I don't know if an inductive cooktop can be run duty cycle and if you > will be able to find an SSR that will put up with the abuse. It would > definitely be cheaper and easier to use a resistive element like the > standalone ones you can get for $15 at any department store. To go > the variac route you would need to build a coupling and mount for a > servo motor and then build your own temp sensor and PID to drive it; > stock PIDs can read a thermocouple and drive an SSR already. > > It sounds like you are trying to build an automated pan-roaster. I > have my doubts that a PID would ever be able to manage such a chaotic > and massive system. You would probably need to sample over such a > large time frame - tens of seconds - and react so slowly that you > would not have the fine control that you are pursuing in the first > place. It's a long trip from the range to the bean mass. > >>From my experience in pan roasting the most important factor is bean > movement. You MUST keep the beans in motion in both dimensions. You > ability to roast in a controlled way will be a result of finding the > right balance between heat transfer from the pot (surface area), > charge size (total mass to heat), and stirring (getting that heat into > all surfaces of all the beans the same). > > Good luck and don't let the nay-sayers like me keep you from > experimenting. >
|
| | | |
Date: 20 Feb 2007 21:43:00
From: Johnny
Subject: Re: Home roasting thoughts
|
"Jonathan Thiessen" <jjthiessen@student.math.uwaterloo.ca > wrote in message news:erfnr1$l1v$1@rumours.uwaterloo.ca... > I'm not sure if I'll actually get to experimenting for a couple months > yet [when I get back home for the summer], so for right now I'm just > trying to toss some ideas around [Both in my head, and out to people > with better roasting and electrical/PID experience]. My original thought > was that a drum would be better, but I like the idea of inductive > cooking [roasting in this case], <snip/> don't spose there's a way to heat the drum inductively is there? I guess it's too big...
|
| | | | |
Date: 21 Feb 2007 02:08:42
From: Jonathan Thiessen
Subject: Re: Home roasting thoughts
|
I'm not actually to sure on how it all works other than it uses magnetic induction. The reasoning was to lessen the thermal mass, and thus have a more responsive system. I think it would require encasing the drum in the inductive-cooktop-surface-stuff which sounds rather custom and expensive to me **shrugs** Very well might be possible, but yeah... I dunno. Johnny wrote: > "Jonathan Thiessen" <jjthiessen@student.math.uwaterloo.ca> wrote in message > news:erfnr1$l1v$1@rumours.uwaterloo.ca... >> I'm not sure if I'll actually get to experimenting for a couple months >> yet [when I get back home for the summer], so for right now I'm just >> trying to toss some ideas around [Both in my head, and out to people >> with better roasting and electrical/PID experience]. My original thought >> was that a drum would be better, but I like the idea of inductive >> cooking [roasting in this case], <snip/> > > don't spose there's a way to heat the drum inductively is there? I guess > it's too big... > >
|
| | | |
Date: 20 Feb 2007 16:19:08
From: Jonathan Thiessen
Subject: Re: Home roasting thoughts
|
Oh yeah... I forgot to say, [with respect to the espresso machine] if one is going to control the piston via some on device controller, or a standalone computer, you might as well have precise control over the brewing temps too since water is heated on a per shot basis. This would definitely be handy if, say, you perfected your shot pulling, and then you went to barista competitions in both Death Valley, and on Everest ;) [I think it'd be neat at least if not practical]. Even if it wasn't really a production machine, it'd be a good machine for espresso research... I'll have to see if I can get an NSERC grant for that... seriously :) Jonathan Thiessen wrote: > I'm not sure if I'll actually get to experimenting for a couple > months yet [when I get back home for the summer], so for right now I'm > just trying to toss some ideas around [Both in my head, and out to > people with better roasting and electrical/PID experience]. My original > thought was that a drum would be better, but I like the idea of > inductive cooking [roasting in this case], and I couldn't really think > of anyway of keeping with both. In my thinking, gas/propane really would > be the best method, however, sort of that, I would think it best to make > the heating as direct as possible so as to avoid the issues of thermal > mass affecting control [inductive, light, microwave?]. One issue with > microwave is that it excites water [any moisture?] within, rather than > being radiant [heat wise]. > > Which reminds me... I also have an idea for an espresso machine, and > I think it'd be awesome if ever I did actually pursue it [maybe one of > these days when I'm back at home :)]. But yeah... The idea is to make > the machine as thermally insulated/non-conducting as possible, and to > dose water into a chamber [expressly for you :P] where it is heated > using microwaves, and then forced through the coffee puck by a PLC'd > hydraulic piston. I believe this would lead to the ultimate extraction > given the instant on/instant off thermal stability, and controllable > [read smooth rampable] flow rate/pressure. It would be a _relatively_ > simple design, and it would offer all the advantages of a piston/lever > machine, but it would be completely controllable/consistent/ever > predictable. The only possible disadvantage that I can think of is maybe > cost [And I suppose that if you really want to make milk beverages, then > you'll have to look elsewhere to steam/froth... Oh, and I suppose it > would take a bit longer to make a shot given that water is heated on a > per shot basis [Although the nice thing is that idle draw ->0W], so make > that three disadvantages]. > > > Calvin wrote: >> On Feb 19, 5:43 pm, Jonathan Thiessen >> <jjthies...@student.math.uwaterloo.ca> wrote: >>> Salutations, >>> >>> I was thinking, and I've come up with an idea. Whether it's a >>> good [or >>> original] idea, or not, I'm not sure. The plan is to use a portable >>> induction cooktop with... a pot. The idea is also to have an overhead >>> electric motor driving a mixing blade, and also to run the cooktop >>> through a variac which is magically controlled by a fancy temperature >>> controller like the nice Fuji ones. One of the very nice things about >>> induction cooktops is that they are rather responsive [much like gas >>> burners]. In my thinking though, this sort of responsiveness doesn't >>> mean much if it can't be controlled smoothly [analogue-like, or at least >>> multi-step]. I've never actually used an induction cooktop before, but >>> we have a halogen one, and the most annoying aspect of it is that the >>> different temp settings are realized by it turning off, and on >>> occasionally which yields a most inconsistent/erratic temp that is >>> useless for cooking anything but water. I wouldn't want the same sort of >>> issue with my coffee roasting apparatus. But maybe I'm off on this one >>> **shrugs**. >>> >>> My concerns are: >>> 1. Running an electric motor close to an induction cooktop. Is this a >>> problem? [Both being magnetic devices, and all] >>> 2. Are there temp controllers that are "analogue", or are they all >>> "digital" in design? That is to say, will they output at a constant >>> voltage, or off; or can they output smoothly over a range [Lets say >>> you're ramping up, but going to fast. Instead of letting it go until >>> it's over temp, it should give a decrease in voltage signaling that the >>> heater should give a reduced output, and thus avoiding overshooting, and >>> undershooting]. Should I even be concerned with this? Will it make a >>> difference? Am I better off to just control a relay with the temp >>> controller, rather than bothering with smooth temp transition? >>> 3. Are there variacs that can be controlled via some control voltage. In >>> other words, can we somehow scale the control voltage output from the >>> temp controller up to the 0-120VAC sort of range. >>> 4. Is it ok/safe to run induction cooktops at a reduced voltage? Should >>> I look for a purely analogue cooktop so that I can set it full-bore, and >>> let the variac do it's thing? [That is, will running a digitally >>> controlled unit on a variac screw it up?]. >>> 5. Is this all-round just a really bad idea? I mean... I really quite >>> like it conceptually so long as it's possible, and [economically] >>> feasible. What are your thoughts? >>> >>> Thank you for your time. >>> Have a good one ;) >>> //jonathan >> >> I don't know if an inductive cooktop can be run duty cycle and if you >> will be able to find an SSR that will put up with the abuse. It would >> definitely be cheaper and easier to use a resistive element like the >> standalone ones you can get for $15 at any department store. To go >> the variac route you would need to build a coupling and mount for a >> servo motor and then build your own temp sensor and PID to drive it; >> stock PIDs can read a thermocouple and drive an SSR already. >> >> It sounds like you are trying to build an automated pan-roaster. I >> have my doubts that a PID would ever be able to manage such a chaotic >> and massive system. You would probably need to sample over such a >> large time frame - tens of seconds - and react so slowly that you >> would not have the fine control that you are pursuing in the first >> place. It's a long trip from the range to the bean mass. >> >>> From my experience in pan roasting the most important factor is bean >> movement. You MUST keep the beans in motion in both dimensions. You >> ability to roast in a controlled way will be a result of finding the >> right balance between heat transfer from the pot (surface area), >> charge size (total mass to heat), and stirring (getting that heat into >> all surfaces of all the beans the same). >> >> Good luck and don't let the nay-sayers like me keep you from >> experimenting. >>
|
| |
Date: 20 Feb 2007 09:43:29
From:
Subject: Re: Home roasting thoughts
|
On Feb 19, 3:43 pm, Jonathan Thiessen <jjthies...@student.math.uwaterloo.ca > wrote: > Salutations, > > I was thinking, and I've come up with an idea. Whether it's a good [or > original] idea, or not, I'm not sure. The plan is to use a portable > induction cooktop with... a pot. The idea is also to have an overhead > electric motor driving a mixing blade, and also to run the cooktop > through a variac which is magically controlled by a fancy temperature > controller like the nice Fuji ones. One of the very nice things about > induction cooktops is that they are rather responsive [much like gas > burners]. In my thinking though, this sort of responsiveness doesn't > mean much if it can't be controlled smoothly [analogue-like, or at least > multi-step]. I've never actually used an induction cooktop before, but > we have a halogen one, and the most annoying aspect of it is that the > different temp settings are realized by it turning off, and on > occasionally which yields a most inconsistent/erratic temp that is > useless for cooking anything but water. I wouldn't want the same sort of > issue with my coffee roasting apparatus. But maybe I'm off on this one > **shrugs**. > > My concerns are: > 1. Running an electric motor close to an induction cooktop. Is this a > problem? [Both being magnetic devices, and all] > 2. Are there temp controllers that are "analogue", or are they all > "digital" in design? That is to say, will they output at a constant > voltage, or off; or can they output smoothly over a range [Lets say > you're ramping up, but going to fast. Instead of letting it go until > it's over temp, it should give a decrease in voltage signaling that the > heater should give a reduced output, and thus avoiding overshooting, and > undershooting]. Should I even be concerned with this? Will it make a > difference? Am I better off to just control a relay with the temp > controller, rather than bothering with smooth temp transition? > 3. Are there variacs that can be controlled via some control voltage. In > other words, can we somehow scale the control voltage output from the > temp controller up to the 0-120VAC sort of range. > 4. Is it ok/safe to run induction cooktops at a reduced voltage? Should > I look for a purely analogue cooktop so that I can set it full-bore, and > let the variac do it's thing? [That is, will running a digitally > controlled unit on a variac screw it up?]. > 5. Is this all-round just a really bad idea? I mean... I really quite > like it conceptually so long as it's possible, and [economically] > feasible. What are your thoughts? > > Thank you for your time. > Have a good one ;) > //jonathan For starters, here are some personal criteria I'd have to satisfy before embartking on complex invention. Not inclusive or necessarily the order of importance: 1. I'd have to be an excellent and experienced cupper. Not just I- know-what-I-like, but having a wide range of controlled and confirmed experience. Otherwise, how could I trust any of my findings along the way? How could I sensibly draw from the experiences of a far-flung community of other experts? 2. I'd have to know what particular aspects of current technology I want to improve upon. This would require some experience with a variety of current roasting methods. Simply demonstrating that I could make a decent roast happen would not not be enough. I'd want to target a batch size range; not build the unit and then see how much it could roast. OTOH, if the materials and assembly were handy and cheap, it's worth trying anything on little more than a hunch. 3. Convenient strorage, aestheticly pleasing, and robustly built should not be afterthoughts, but considerations from the very begining. These account for much of the cost of off-the-shelf quality roasters. So is the goal to build a cheaper Hottop or Probat with the minor inconveniences of a tangle of exposed wires, corners that singe and rip flesh, tripped breakers, and which you operate from the floor of an unheated garage? tin
|
| | |
Date: 20 Feb 2007 19:23:25
From: Ed Needham
Subject: Re: Home roasting thoughts
|
You work for the government policies and procedures office, right? (g) <coffeeemail@gmail.com > wrote in message news:1171993409.710749.112250@h3g2000cwc.googlegroups.com... > For starters, here are some personal criteria I'd have to satisfy > before embartking on complex invention. Not inclusive or necessarily > the order of importance: > 1. I'd have to be an excellent and experienced cupper. Not just I- > know-what-I-like, but having a wide range of controlled and confirmed > experience. Otherwise, how could I trust any of my findings along the > way? How could I sensibly draw from the experiences of a far-flung > community of other experts? > 2. I'd have to know what particular aspects of current technology I > want to improve upon. This would require some experience with a > variety of current roasting methods. Simply demonstrating that I > could make a decent roast happen would not not be enough. I'd want to > target a batch size range; not build the unit and then see how much it > could roast. OTOH, if the materials and assembly were handy and cheap, > it's worth trying anything on little more than a hunch. > 3. Convenient strorage, aestheticly pleasing, and robustly built > should not be afterthoughts, but considerations from the very > begining. These account for much of the cost of off-the-shelf quality > roasters. So is the goal to build a cheaper Hottop or Probat with the > minor inconveniences of a tangle of exposed wires, corners that singe > and rip flesh, tripped breakers, and which you operate from the floor > of an unheated garage? > tin >
|
|