Popper Chimney

[Paul]

Re: Popper Chimney

Hi ,

My popper behaves the same as yours Mal , as the batch size increases the roast shortens, also it becomes hard to differentiate between 1st and 2nd crack it tends to be a continous crack and you have to judge by colour alone.

Paul

[Dimal]

Re: Popper Chimney

Hi ,

My popper behaves the same as yours Mal , as the batch size increases the roast shortens, also it becomes hard to differentiate between 1st and 2nd crack it tends to be a continous crack and you have to judge by colour alone.

Paul

Hi Paul,

Yep, I think when the roast time is as short as that, the quality of the roast suffers somewhat too. There are a myriad of mods that one can do to try and extend the roast time, some simple and several that are more complex. I dont know if youve seen this site before but there are some interesting variations on a theme here to achieve just that... http://www.homeroaster.com/homemade.html.

A lot depends on the type of popper you have and what design the manufacturer has used for the innards, but for most there is usually something that can be done. Its interesting to see what some "bright sparks" have come up with though to gain more control over their roasts. A lot of the mods mentioned in HomeRoaster require the close assistance of an electrician though and unless you know someone who is qualified, it is best to leave these types of mods alone. You can always work a deal though, a Kilo of excellent freshly roasted coffee to a sparky with more interests than just electrons.... might be worth a go . Anyway, all the best in sorting things out,

Cheerio,
Mal.

[nunu]

Re: Popper Chimney

With regards to batch size vs. roast time, only the initial ramping up of temperature should be affected. If everything else is held constant, then if you increase the mass, it should take longer to heat. So up until first crack should take slightly longer. The rest of the roast will take a similar time. If youve exceeded the max hypothetical batch size for your popper, it will often turn of via the thermal overload once it reaches first crack. Every time Ive gotten a bit greedy, Ive been bitten around the same time each time. For me, the magic number is 150g.

[Dimal]

Re: Popper Chimney

Well.....

Not really nunu. As the batch size is increased, this poses an increased restriction to the air flow which then allows the heating element to get hotter and therefore heat the air even more. This holds true regardless of when you take the temperature measurements, the general relationship remains the same. Ive gone through this process about a hundred times with my Mistral poppers and the recordings Ive made bear this out each and every time.

I guess that if you have a popper with a particularly strong fan/air-flow, then this characteristic will shift up the batch size curve somewhat and possible give a different impression. Id be surprised if the same general behaviour didnt occur though....

Mal.

[Paul]

Re: Popper Chimney

Hi Nunu,

What brand popper do you have? It must have a pretty good fan on it

Paul

[nunu]

Re: Popper Chimney

Its a Chief brand popper, and I believe it is the same as the Mistral. Picked it up from Good Guys for like 20 bucks.

From my experience with this popper, once the beans start to move on their own, the air flow isnt too restricted. We all know the beans lose mass as they heat/expand due to loss of moisture, etc. When the batch is nearly finished, they are getting chucked out of the extended chimney, unless the popperdom is in place. Ive had nearly half a batch get tossed all over the bench, so my poppers fan is quite the beast.

Ill reiterate...There is a definite threshold for me at 150g. Any more than this, and my popper will go into overload and shut down. It has never shut down at 150g, so that remains my optimal batch size.

[AndyCJ]

Re: Popper Chimney

Do you mean it shuts down the popper? Like the thing turns itself off? Odd.

Ive got a Mistral, and it hammers, the fan is super strong compared to the B&D popper, even with 200gm in it! - I have to stir it for a little bit, but once the beans move its fine (30-40 seconds of stir).

If you didnt have the "cut out" then youde be able to put more in even! Pity.

[nunu]

Re: Popper Chimney

I wish it didnt have a thermal cutoff. Id remove it, but I really dont like removing safety features from appliances. The popper is useless for like 5-10 minutes when it shuts down. Im sure it would work with 200g in it if there was no thermal cutoff. Im happy with doing 150g at a time. Ive been a bit busy, so my coffee consumption is down a bit. 150g now lasts several days.

[Dimal]

Re: Popper Chimney

Geez nunu,

Nothing wrong with 150 grams from a popper and Andy, 200 grams 8-)..... you must have to bolt it to the bench to stop it from trying to take off ;D,

Mal.

[nunu]

Re: Popper Chimney

I need to drill some holes in it, so it takes in more air. If you look at my roast times, one finished at 7:30, and the other at 9:00. The first batch took 4:30 to cool, while the second took about 4 minutes to cool. 4-5 minute cooling cycle is what several of the purpose-built home roasters have standard, so thats comparable. The only difference is in the roast length. Im looking at half the time, which some will say is fine, while others say its too short. I havent been able to compare between the two, since I dont have a purpose-built home roaster.

About the only way to extend the roast time to that of the Hottop, etc., is to roast in a coolroom or move to Tassie. Even then, I think it will have maybe a couple minutes of a difference. That will at least get me into double digits for roast time.

150g roaster for around 30 bucks (popperdom and very special soup included) is quite a deal indeed.

[AndyCJ]

Re: Popper Chimney

Yeah Mal - I hear ya about bolting it down!  Its a badboy for sure!  The tin can is the biggest tin I could find so the beans dont fly out!  Im hardly ever going to use it from now on thou - perhaps if I run out, but thats unlikely now Ive got the "Badboy 77".

150g is ok, but if you want to extend the roast time Nunu, then take some beans out.  Thatll mean more airflow through the beans that are in the chamber, and slower overall roast time.  Give it a go and see what happens if you drop 20g?  Youll probably have to do a couple of batches then thou hey

What you need... is a heatgun and a nice shiney new dogbowl, and a wisk.  Im telling ya - once youve gone the gun the popper will be only used for emergencies.  Dogbowl substitutes could be a large collander too.

The main thing with the HG is - total control of temprature/time of roast.

XU1 Heatgun @ Bunnings $18, Dogbowl @ Petstore $??  (cant be more than a tenner thou?), Stainless Wisk $5 = Cant be more than $35-40 all up.

[csutak40]

Re: Popper Chimney

Yep,

Broke my Lantern Chimney a while back too >. Without missing a beat, grabbed one of a few empty soup tins that I keep on hand for such occasions, snipped the V out of the bottom after removing the base and Bobs your uncle. Most of our soup has been the Heinz Special variety in the extra tall tins, and these seem to work extremely well 8-). Dont think Ill bother with replacing the Lantern Chimney, even though it allowed great visibility for gauging the roast progression by colour.

Mal.

Easy for you, difficult for me    Im about to do my first roast.  Got my tin (extra long tomato juice) first I cut a straight line up, attempted to squeeze the ends togehter to fit into the popper, the only thing I succeeded in is cutting my hand in several places OUCH!!!

Then I cut a V out of it (gee, Im clever, managed to think of doing this before I read this thread  ;D)  More cuts, but success!  Also managed to end up with some tin shavings, at least one of which landed on the floor, then in my foot    Should have listened to my mother when she told me that only peasants walk around barefoot!  ;D

Well, only partly successful, now there is a sharp bit bulging out half way up the tin.  Im sure Im going to cut my hands on it lots of times.  Cant think to a way to get rid of that bulge.
 

[Javaphile]

Re: Popper Chimney

Well, only partly successful, now there is a sharp bit bulging out half way up the tin. Im sure Im going to cut my hands on it lots of times. Cant think to a way to get rid of that bulge.

If nothing else get some Exhaust Duct repair tape. Its basicly a heavy alum foil with an adhesive backing designed to be used on the exhaust vents of furnaces and water heaters and should be able to withstand the temps involved.

If the sharp point sticks out significantly use a hammer to knock it in, putting the can on any round hard object. A thick oak dowel rod will work if nothing else. Then put the tape on as a final cover.

Java "Taking a smoke/cuppa break from the reassembly" phile

[nunu]

Re: Popper Chimney

Maybe I should have added a disclaimer about being careful with sharp edges created when you cut the tin.

About the bump, it shouldnt be that much of a deal, although when I was experimenting with cutting different shapes from the tin to allow the sides to overlap, and make the tube smaller, the v-shape created a very large bump, with the straight cut yielding a much smaller bump. as long as there is an overlap of the cut sides, the majority of the heat will still escape up through the top.

I should have also explained that an easier way to squeeze the tin to overlap is by gently squeezing the sides, as you push the tin into the popper chamber. This forces the tin to constrict, and you dont have to deal much with the sharp edges. It also creates a much more snug fit, as the diameter of the "shrunken" tin is closer to the inside diameter of the popper chamber.

I apologise for any misconception and harm caused by my lack of explanation.

[csutak40]

Re: Popper Chimney

Maybe I should have added a disclaimer about being careful with sharp edges created when you cut the tin.

About the bump, it shouldnt be that much of a deal, although when I was experimenting with cutting different shapes from the tin to allow the sides to overlap, and make the tube smaller, the v-shape created a very large bump, with the straight cut yielding a much smaller bump.  as long as there is an overlap of the cut sides, the majority of the heat will still escape up through the top.

I should have also explained that an easier way to squeeze the tin to overlap is by gently squeezing the sides, as you push the tin into the popper chamber.  This forces the tin to constrict, and you dont have to deal much with the sharp edges.  It also creates a much more snug fit, as the diameter of the "shrunken" tin is closer to the inside diameter of the popper chamber.

I apologise for any misconception and harm caused by my lack of explanation.

Definitely not your fault!  Firstly, it is common sense that one should be careful about sharp edges. I did try! I just happen to be a klutz!   :P  I did, more or less, do as you describe, (squeeze the tin as I was pushing it into the popper) but still managed to cut myself  :  Possibly because I have carpal tunnel AND tennis elbow, so not much strenght in my hands