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Date: 05 Jun 2007 21:26:50
From: Steve Ackman
Subject: Roaster got a new gas jet
This is my first roaster improvement project on
the lathe. I had started to turn an existing (cast)
4" flange into an air control shutter index, but the
existing bolt circle was so far eccentric from the
OD that it never got past facing, when I realized
it wasn't going to work without a lot more effort
than I wanted to put into it. (Next time I think
about this seriously, I'll probably do it from
scratch in brass plate.)

Of course, the first thing I did on the lathe was
to remove the bottom of a portafilter... I'm sure it
would have been quicker with a hole saw on the drill
press, but there's something more satisfying about
grinding a trepanning tool and doing it on the lathe.

In neither the coffee world, nor the metalworking
world, would this have probably evoked more than a
mild shoulder shrug... so you never heard about it,
or saw pictures. ;-)

Many years ago, I made parts that ended up in
reactor compartments of submarines... ground shafts
to tolerances of +/-.0000" and did a lot of really
amazing stuff... but what's really amazing is how much
satisfaction comes from a stupid little project like
this.

http://twoloonscoffee.com/machine/gas-jets.html




 
Date: 06 Jun 2007 23:11:47
From: David Billington
Subject: Re: Roaster got a new gas jet


Steve Ackman wrote:

> This is my first roaster improvement project on
>the lathe. I had started to turn an existing (cast)
>4" flange into an air control shutter index, but the
>existing bolt circle was so far eccentric from the
>OD that it never got past facing, when I realized
>it wasn't going to work without a lot more effort
>than I wanted to put into it. (Next time I think
>about this seriously, I'll probably do it from
>scratch in brass plate.)
>
> Of course, the first thing I did on the lathe was
>to remove the bottom of a portafilter... I'm sure it
>would have been quicker with a hole saw on the drill
>press, but there's something more satisfying about
>grinding a trepanning tool and doing it on the lathe.
>
> In neither the coffee world, nor the metalworking
>world, would this have probably evoked more than a
>mild shoulder shrug... so you never heard about it,
>or saw pictures. ;-)
>
> Many years ago, I made parts that ended up in
>reactor compartments of submarines... ground shafts
>to tolerances of +/-.0000" and did a lot of really
>amazing stuff... but what's really amazing is how much
>satisfaction comes from a stupid little project like
>this.
>
>http://twoloonscoffee.com/machine/gas-jets.html
>
You would probably love to drive into Utrecht in Holland by one of the
main southern access roads, Douwe Egbert have a roasting plant there and
you can smell it for a mile or more when downwind, you don't need to
drink it, it's a stimulating smell.



  
Date: 07 Jun 2007 16:45:47
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <46673123.7030003@djbillington.freeserve.co.uk >, on Wed, 06 Jun 2007
23:11:47 +0100, David Billington wrote:

> You would probably love to drive into Utrecht in Holland by one of the
> main southern access roads, Douwe Egbert have a roasting plant there and
> you can smell it for a mile or more when downwind, you don't need to
> drink it, it's a stimulating smell.

I was there in '79 (the outskirts, anyway).
Don't recall any coffee smells at that time. ;-)

Maxwell House used to have a roastery practically
downtown in Jacksonville, FL. Even roasting coffee
that horrid smelled good to me, but apparently not to
anyone else. They closed it down several years ago,
IIRC, due to complaints about the smell.


   
Date: 07 Jun 2007 22:57:19
From: David Billington
Subject: Re: Roaster got a new gas jet


Steve Ackman wrote:

>In <46673123.7030003@djbillington.freeserve.co.uk>, on Wed, 06 Jun 2007
>23:11:47 +0100, David Billington wrote:
>
>>You would probably love to drive into Utrecht in Holland by one of the
>>main southern access roads, Douwe Egbert have a roasting plant there and
>>you can smell it for a mile or more when downwind, you don't need to
>>drink it, it's a stimulating smell.
>>
>
> I was there in '79 (the outskirts, anyway).
>Don't recall any coffee smells at that time. ;-)
>
> Maxwell House used to have a roastery practically
>downtown in Jacksonville, FL. Even roasting coffee
>that horrid smelled good to me, but apparently not to
>anyone else. They closed it down several years ago,
>IIRC, due to complaints about the smell.
>
It may depend on the time of day, a quick google search for 'douwe
egbert utrecht' turned up many hits but all seemed to be in dutch, one
link led to an english page in wiki
http://en.wikipedia.org/wiki/Douwe_Egberts . Maybe the problem with MH
being the coffee, I recall the US being up for coffee when I lived there
but the coffee in europe seems so much better, or just read stronger
depending on your tastes. Reminds me of a story a UK guy told me, he was
coming back from a stay in the US on a Lufthansa flight and the first
thing most germans did when entering the plane was to ask the steward
for some decent coffee, all down to what you are used too I suppose. I
don't drink that much coffee in the UK these days, but when in europe I
drink mostly coffee as the tea is nowhere near as good as what we get in
the UK.



  
Date: 06 Jun 2007 16:33:16
From: Roger Shoaf
Subject: Re: Roaster got a new gas jet

"David Billington" <djb@djbillington.freeserve.co.uk > wrote in message
news:46673123.7030003@djbillington.freeserve.co.uk...
>
> You would probably love to drive into Utrecht in Holland by one of the
> main southern access roads, Douwe Egbert have a roasting plant there and
> you can smell it for a mile or more when downwind, you don't need to
> drink it, it's a stimulating smell.
>

Unless you are down wind while they are roasting. The smoke that comes off
during roasting is similar to somebody burning a pile of half dry grass (as
in lawn grass). It only smells wonderful after the coffee is roasted.

--

__
Roger Shoaf

Important factors in selecting a mate:
1] Depth of gene pool
2] Position on the food chain.






   
Date: 07 Jun 2007 16:48:46
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <1181172816.20309@news01.syix.com >, on Wed, 6 Jun 2007 16:33:16
-0700, Roger Shoaf wrote:
>
> The smoke that comes off
> during roasting is similar to somebody burning a pile of half dry grass (as
> in lawn grass). It only smells wonderful after the coffee is roasted.

It smells pretty good to me at just about any stage
of the roast... but the aromas of offgassing from about
+1 hr to about +48 hrs post roast just can't be beat.
Nothing in the world smells better than that!


 
Date: 06 Jun 2007 10:20:59
From: kfvorwerk@gmail.com
Subject: Re: Roaster got a new gas jet
Nice work. You need to build the Open Column Launch Engine mentioned
on the lathe page. Then get a launch. African Queen time.
Karl



On Jun 5, 3:26 pm, Steve Ackman <s...@SNIP-THIS.twoloonscoffee.com >
wrote:
> This is my first roaster improvement project on
> the lathe. I had started to turn an existing (cast)
> 4" flange into an air control shutter index, but the
> existing bolt circle was so far eccentric from the
> OD that it never got past facing, when I realized
> it wasn't going to work without a lot more effort
> than I wanted to put into it. (Next time I think
> about this seriously, I'll probably do it from
> scratch in brass plate.)
>
> Of course, the first thing I did on the lathe was
> to remove the bottom of a portafilter... I'm sure it
> would have been quicker with a hole saw on the drill
> press, but there's something more satisfying about
> grinding a trepanning tool and doing it on the lathe.
>
> In neither the coffee world, nor the metalworking
> world, would this have probably evoked more than a
> mild shoulder shrug... so you never heard about it,
> or saw pictures. ;-)
>
> Many years ago, I made parts that ended up in
> reactor compartments of submarines... ground shafts
> to tolerances of +/-.0000" and did a lot of really
> amazing stuff... but what's really amazing is how much
> satisfaction comes from a stupid little project like
> this.
>
> http://twoloonscoffee.com/machine/gas-jets.html




  
Date: 06 Jun 2007 13:41:04
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <1181125259.143538.183000@r19g2000prf.googlegroups.com >, on Wed, 06
Jun 2007 10:20:59 -0000, kfvorwerk@gmail.com wrote:

> Nice work.

Thanks.

> You need to build the Open Column Launch Engine mentioned
> on the lathe page. Then get a launch. African Queen time.

The engine is sized for a launch about 24" long...
maybe. African Queen Bee, maybe.



 
Date: 05 Jun 2007 21:59:48
From: Craig Andrews
Subject: Re: Roaster got a new gas jet

"Steve Ackman" <steve@SNIP-THIS.twoloonscoffee.com > wrote in message
news:slrnf6c3aq.pbf.steve@wizard.dyndns.org...
> This is my first roaster improvement project on
> the lathe. I had started to turn an existing (cast)
> 4" flange into an air control shutter index, but the
> existing bolt circle was so far eccentric from the
> OD that it never got past facing, when I realized
> it wasn't going to work without a lot more effort
> than I wanted to put into it. (Next time I think
> about this seriously, I'll probably do it from
> scratch in brass plate.)
>
> Of course, the first thing I did on the lathe was
> to remove the bottom of a portafilter... I'm sure it
> would have been quicker with a hole saw on the drill
> press, but there's something more satisfying about
> grinding a trepanning tool and doing it on the lathe.
>
> In neither the coffee world, nor the metalworking
> world, would this have probably evoked more than a
> mild shoulder shrug... so you never heard about it,
> or saw pictures. ;-)
>
> Many years ago, I made parts that ended up in
> reactor compartments of submarines... ground shafts
> to tolerances of +/-.0000" and did a lot of really
> amazing stuff... but what's really amazing is how much
> satisfaction comes from a stupid little project like
> this.
>
> http://twoloonscoffee.com/machine/gas-jets.html


Nice work, thanks Steve! {:-D
Will you show us a pic of the new nice bright blue flame on the burner? {;-)
Do you have a pic on the old yellowish flame?
I posted some info almost 4 years ago. The Specific Gravity (S.G) of Propane
is 1.53, Natural gas 0.60 There is a great chart & all technical info posted
on my post here from Mon Jul 14, 2003:
http://www.coffeegeek.com/forums/espresso/machines/15134#15134
Cheers,
Craig.




  
Date: 06 Jun 2007 13:25:14
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <5cmionF2vkq3dU1@mid.individual.net >, on Tue, 5 Jun 2007 21:59:48
-0400, Craig Andrews wrote:
>
> Nice work, thanks Steve! {:-D
> Will you show us a pic of the new nice bright blue flame on the burner? {;-)

Hey... My Kodak DC215 is digital technology from the
last millenium... and what do you expect from a shot
through a 1" hole of about 5" worth of the burner length
anyway?
...and to be honest, that shot was a fluke. Watching in
realtime, yellow licks come and go... just a lot fewer
and smaller ones than before.

I unhooked the stack and vented the roaster inside
today into a volume of ~1900 ft³... initially set to
2"wc, readings go like so:

5:00 - 13 ppm
6:00 - 22 ppm (turned gas up to 4"wc)
8:00 - 29 ppm
10:40 - 36 ppm
12:00 - 36 ppm
13:00 - 44 ppm

When I did this same test into a larger volume,
~2800 ft³ in MN, I hit 200 ppm in less than 20 minutes.

To put that into perspective, OSHA allows 50 ppm over
an 8 hour period, while NIOSH allows 40 ppm and a
ceiling of 200 ppm.
I'm still not really satisfied with the burner
efficiency, but it's certainly a lot better than it was.

> Do you have a pic on the old yellowish flame?

No, but just imagine a campfire, with blue roots.

> I posted some info almost 4 years ago. The Specific Gravity (S.G) of Propane
> is 1.53, Natural gas 0.60

According to the chart I found, at
http://energy.growmark.com/propane/Chapter9.html#Propane%20and%20Natural%20Gas%20Orifice%20Capacities
pure propane through a 1/8" inch jet at 11" wc should
give 117,150 BTU, and reducing the orifice to 7/64"
should give 89,825 BTU.
(Some LP is a blend of propane and butane, which has
a slightly higher heat content.)

Spec sheet for the roaster gives a BTU range as
50,000 to 225,000. Either Roastersexchange was
extremely "optimistic" in their burner rating, or the
chart I found is incorrect, or... something else I
haven't considered.


   
Date: 06 Jun 2007 13:56:00
From: Craig Andrews
Subject: Re: Roaster got a new gas jet

"Steve Ackman" <steve@SNIP-THIS.twoloonscoffee.com > wrote in message
news:slrnf6dri6.2p2.steve@sorceror.wizard.dyndns.org...
> In <5cmionF2vkq3dU1@mid.individual.net>, on Tue, 5 Jun 2007 21:59:48
> -0400, Craig Andrews wrote:
>>
>> Nice work, thanks Steve! {:-D
>> Will you show us a pic of the new nice bright blue flame on the burner?
>> {;-)
>
> Hey... My Kodak DC215 is digital technology from the
> last millenium... and what do you expect from a shot
> through a 1" hole of about 5" worth of the burner length
> anyway?


Umm...ok., I didn't see a pic..., sorry to bother ya..
Craig.


> ...and to be honest, that shot was a fluke. Watching in
> realtime, yellow licks come and go... just a lot fewer
> and smaller ones than before.
>
> I unhooked the stack and vented the roaster inside
> today into a volume of ~1900 ft³... initially set to
> 2"wc, readings go like so:
>
> 5:00 - 13 ppm
> 6:00 - 22 ppm (turned gas up to 4"wc)
> 8:00 - 29 ppm
> 10:40 - 36 ppm
> 12:00 - 36 ppm
> 13:00 - 44 ppm
>
> When I did this same test into a larger volume,
> ~2800 ft³ in MN, I hit 200 ppm in less than 20 minutes.
>
> To put that into perspective, OSHA allows 50 ppm over
> an 8 hour period, while NIOSH allows 40 ppm and a
> ceiling of 200 ppm.
> I'm still not really satisfied with the burner
> efficiency, but it's certainly a lot better than it was.
>
>> Do you have a pic on the old yellowish flame?
>
> No, but just imagine a campfire, with blue roots.
>
>> I posted some info almost 4 years ago. The Specific Gravity (S.G) of
>> Propane
>> is 1.53, Natural gas 0.60
>
> According to the chart I found, at
> http://energy.growmark.com/propane/Chapter9.html#Propane%20and%20Natural%20Gas%20Orifice%20Capacities
> pure propane through a 1/8" inch jet at 11" wc should
> give 117,150 BTU, and reducing the orifice to 7/64"
> should give 89,825 BTU.
> (Some LP is a blend of propane and butane, which has
> a slightly higher heat content.)
>
> Spec sheet for the roaster gives a BTU range as
> 50,000 to 225,000. Either Roastersexchange was
> extremely "optimistic" in their burner rating, or the
> chart I found is incorrect, or... something else I
> haven't considered.




    
Date: 06 Jun 2007 14:42:38
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <5coapjF30p1t9U1@mid.individual.net >, on Wed, 6 Jun 2007 13:56:00
-0400, Craig Andrews wrote:
>
> Umm...ok., I didn't see a pic..., sorry to bother ya..

Oh... I saw the winky and thought you were having
joshin about the small size of the flame in the photo.
It's there alright. At the bottom of the page, mostly
black with a thin line about 1/3 of the way down.

Maybe you need to adjust your monitor to see it.
;-)


  
Date: 05 Jun 2007 22:08:51
From: Craig Andrews
Subject: Re: Roaster got a new gas jet

"Craig Andrews" <alt.coffee@deletethis.rogers.com > wrote in message
news:5cmionF2vkq3dU1@mid.individual.net...
>
> "Steve Ackman" <steve@SNIP-THIS.twoloonscoffee.com> wrote in message
> news:slrnf6c3aq.pbf.steve@wizard.dyndns.org...
>> This is my first roaster improvement project on
>> the lathe. I had started to turn an existing (cast)
>> 4" flange into an air control shutter index, but the
>> existing bolt circle was so far eccentric from the
>> OD that it never got past facing, when I realized
>> it wasn't going to work without a lot more effort
>> than I wanted to put into it. (Next time I think
>> about this seriously, I'll probably do it from
>> scratch in brass plate.)
>>
>> Of course, the first thing I did on the lathe was
>> to remove the bottom of a portafilter... I'm sure it
>> would have been quicker with a hole saw on the drill
>> press, but there's something more satisfying about
>> grinding a trepanning tool and doing it on the lathe.
>>
>> In neither the coffee world, nor the metalworking
>> world, would this have probably evoked more than a
>> mild shoulder shrug... so you never heard about it,
>> or saw pictures. ;-)
>>
>> Many years ago, I made parts that ended up in
>> reactor compartments of submarines... ground shafts
>> to tolerances of +/-.0000" and did a lot of really
>> amazing stuff... but what's really amazing is how much
>> satisfaction comes from a stupid little project like
>> this.
>>
>> http://twoloonscoffee.com/machine/gas-jets.html
>
>
> Nice work, thanks Steve! {:-D
> Will you show us a pic of the new nice bright blue flame on the burner?
> {;-) Do you have a pic on the old yellowish flame?
> I posted some info almost 4 years ago. The Specific Gravity (S.G) of
> Propane is 1.53, Natural gas 0.60 There is a great chart & all technical
> info posted on my post here from Mon Jul 14, 2003:
> http://www.coffeegeek.com/forums/espresso/machines/15134#15134
> Cheers,
> Craig.
>
>

That URL on my post to the "Definitions & Technical Data for LPG, Natural
Gas & LPG/Air Mixtures" is out of date., I'm going to update it on the post
& here it is here: http://www.altenergy.com/Technology/LPGProperties.htm
Craig.




   
Date: 06 Jun 2007 13:38:54
From: Steve Ackman
Subject: Re: Roaster got a new gas jet
In <5cmj9mF30oh0oU1@mid.individual.net >, on Tue, 5 Jun 2007 22:08:51
-0400, Craig Andrews wrote:

> That URL on my post to the "Definitions & Technical Data for LPG, Natural
> Gas & LPG/Air Mixtures" is out of date., I'm going to update it on the post
> & here it is here: http://www.altenergy.com/Technology/LPGProperties.htm

Some interesting stuff there. Bookmarked. I
generally associate complete combustion with blue
flame, but apparently that's not necessarily true with
propane:

"Because of the different number of carbon atoms in propane, propane-air
mixtures produce a flame that is more yellow in color than that of
natural gas. However, the yellow tips are not of any consequence and do
not affect burner operation or efficiency."

44 ppm CO after 13 minutes tells me there's still
room for improvement though. It probably can't come
through further reduction in size of the orifice or I'd
never be able to roast more than 20 lbs. at a time.
Now I have to figure out how to get that gas stream to
draw in more air.