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Using a fan to aid sawdust smouldering

PostPosted: Thu Feb 27, 2014 8:17 pm
by Headbutchersouthwest
Been having trouble with air flow in my cold smoker , so I've been thinking about using a small electric fan to aid with the air flow to help the sawdust to smoulder . I was thinking about a small computer fan but would need a fan that has an adjustable speed controller

Any ideas :roll:

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 6:34 am
by SumpRat
I have done this a few times. I use a small 12v PC fan and it works very well.
I didn't bother with a speed controller, but all you would need is a simple variable resistor AKA POT or potentiometer. Don't know what resistance you would need but shouldn't be too difficult to find out.

The only drawback I found is that the fan will get really gunky as the smoke will go through it. Mine gets very sticky and greasy so much so as it won't self start. A good soaking in WD40 and lots of manual spinning seems to get it going. Once it is going well it stays going.

To "adjust!" the volume of air I just moved then fan in the bottom of the smoker.


Good luck.

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 6:38 am
by BriCan
I'm guessing cuz i know not what you have and set up -- that being said I would crack the door a tad which will let air into the smoker -- hot air rises thus if vent at top you will have air flow -- this is what I did on the smokehouse that I ran/used

Other might have a better answer

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 8:30 am
by GUS
This would be the second thread on the ongoing problems with your Beelonia would it?
Did you sort the poor chimney problem which if I? or are you going to dabble & perhaps get more problems, as we've not seen you (sic) since back in November whats happened with it between then & now?

You inferred (again in your other thread as I recall) that they'd sold you a fan set up to assist airflow / pressure would that be correct? ..if there has been no change you will be assisting with more turbulence, NOT up & out smoke.

Mods, perhaps a good idea to combine threads?

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 10:14 am
by Headbutchersouthwest
GUS wrote:This would be the second thread on the ongoing problems with your Beelonia would it?
Did you sort the poor chimney problem which if I? or are you going to dabble & perhaps get more problems, as we've not seen you (sic) since back in November whats happened with it between then & now?

You inferred (again in your other thread as I recall) that they'd sold you a fan set up to assist airflow / pressure would that be correct? ..if there has been no change you will be assisting with more turbulence, NOT up & out smoke.

Mods, perhaps a good idea to combine threads?


Hi Gus ,

We were really busy over Xmas so decided to leave it until it all settle down hence I haven't be on here to discuss further our problem! But now we have started to adjust things as discussed back before Xmas . We have now shortened the exhaust flue but still the sawdust doesn't smoulder without the aid of the heating element being left on! So we then decided to us a fan which we aimed the air flow to blow over the sawdust to aid with the smouldering which worked really well, so possibly looking at connecting a small PC fan to blow a gentle breeze over to help smoulder the dust!
It's kinda unbelievable that we have spent £5000 on a smoker & the manufacturers don't want to know , they don't answer any emails or nothing :roll:

As for the fan they fitted , well that's situated at the back of the actual smoker which is to aid the circulation of the smoke around the meat and not really to do with the air flow from outside smoke box thru to smoker

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 10:34 am
by GUS
No, I do understand xmas being a peak period.

Any additional air flow will have an affect on a flue stack regardless of where a fan is sited (it's the overall effect).

Site is playing up for me today so it only delivered a short version of what I was trying to say, (& possibly therefore sounding a tad abrupt, (not my intention), when you've time can you pop another pic of the now shortened & presumably upright flue, as this is my primary concern in knocking anything out of the equation.

I noted in the pics previously wet slab of concrete, was this just run off from the roof or is it sited on a bit of land that is particularly wet, (I remember a steam engine renovation firm in a new but badly built agricultural unit with a constantly wet floor) & am hoping there are no peculiar outside influences tweaking this into a state of "no-play" by your Beelonia.

Have you contacted your local trading standards yet? £5k investment not to be sniffed at if dealer network still not helping.

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 10:41 am
by GUS
Another flue related concern from all your previous pics were the amount of visible dog legs in your stainless flue within the unit itself (NOT the overhead exhaust flue I keep banging on about). were there anymore where the flue disappeared or was that the final one going straight into the smoker chamber?

I know it's not a woodburning stove, but the same sort of principals can be applied where smoke is an issue.

Where are you keeping your wood dust, do you microwave it prior to lighting to rid some of the absorbed moisture? is there any moisture forming in the firing section, again denoting damp as your unit appears very open air, directional wind, shielding etc?

Sorry to pluck at straws but cover all bases eh!?

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 11:10 am
by Headbutchersouthwest
Photo of exhaust flue

Image

Image

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 11:23 am
by Headbutchersouthwest
Outside smoke box in now off the floor on a stand , but the pipe is not connected as I were going to fit a flexi pipe

Image

Photo below shows the pipe coming out of outside smoke box and if you look to the bottom left you can see the pipe attachment from the smoker which is inside our prep room

Image

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 12:28 pm
by GUS
Thanks,
You have plenty of flexi still, is it convenient to bung some Screwfix stove cement as a smoke joint (cheap stuff) to bodge it in place, or are you simply using a plug of silicone to keep it airtight?

Nice to see the exit flue greatly shortened, but it's still running heavily sideways, was there no way of pointing it up more or less straight & through the roof ?, this would assist the draw of the fire / smoulder & hopefully play a better part in the smoulder process taking proper hold & not going out.
(a chinamans hat or even an offcut of some flexi would do, siliconed or cemented into place (albeit sharp edged) ..i'm wary of spending any (more) money!

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 12:39 pm
by GUS
Your outside smoke, dust box, I'm hoping the stainless steel is the adjustable type? (mine is still adjustable after 5 yrs on a stove, I simply mark on a best angle line across the angles if so you could knock some length off your tubing & have a straighter in flow rather than forcing it down as it enters into the main box, not that i'm a pro here, but surely that gathers & slows the initial flow, thus making the smoke slightly stale even at this point).
"looks like" you've got 4 or 5 pieces there!?

Was this professionally fitted from the outset? & if so, surely the fitter should be part of the equation as to sorting it out, goodwill or refund of parts fitted that may never have been required.

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 12:51 pm
by GUS
I'm confused as to the smooth metal stainless steel in that picture (towards bottom left of the pic, ..is that in use? if so what for at this point & previously.

to improve throughflow draught obviously you want controlled ventilation but sealed everywhere else for best operation, (if you've ever seen a cheap woodburning stove with badly sealed & badly cast doors & compared that with a well sealed unit the difference is massive), so if not used try capping it off temporarily to check difference in draw & general flow*, I would also limit the air around your lit dust to see how this affects pull over a pre-ordained time period.

*inflate a balloon in the sucker & tie it off or stuff crumpled newspaper in & a plastic showercap over the end this might show better take of smoke with an active draw, are there any broken seals anywhere or are all of this type leaky?

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 12:59 pm
by Headbutchersouthwest
GUS wrote:Thanks,
You have plenty of flexi still, is it convenient to bung some Screwfix stove cement as a smoke joint (cheap stuff) to bodge it in place, or are you simply using a plug of silicone to keep it airtight?

Nice to see the exit flue greatly shortened, but it's still running heavily sideways, was there no way of pointing it up more or less straight & through the roof ?, this would assist the draw of the fire / smoulder & hopefully play a better part in the smoulder process taking proper hold & not going out.
(a chinamans hat or even an offcut of some flexi would do, siliconed or cemented into place (albeit sharp edged) ..i'm wary of spending any (more) money!


The pipe that is fitted is 120mm , I was going to buy some bigger flex to fit over the existing pipe & fix it using the pipe clamps so it's tight!
We could fit new vertical exhaust pipe , just means cutting out ceiling & moving pipe into place!

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 1:03 pm
by Headbutchersouthwest
GUS wrote:I'm confused as to the smooth metal stainless steel in that picture (towards bottom left of the pic, ..is that in use? if so what for at this point & previously.

to improve throughflow draught obviously you want controlled ventilation but sealed everywhere else for best operation, (if you've ever seen a cheap woodburning stove with badly sealed & badly cast doors & compared that with a well sealed unit the difference is massive), so if not used try capping it off temporarily to check difference in draw & general flow*, I would also limit the air around your lit dust to see how this affects pull over a pre-ordained time period.

*inflate a balloon in the sucker & tie it off or stuff crumpled newspaper in & a plastic showercap over the end this might show better take of smoke with an active draw, are there any broken seals anywhere or are all of this type leaky?



The smooth pipe in bottom left of photo is the pipe leading into the main smoker from smoke box , but we decided to move the smoke box onto a stand so it was off the floor and drawing more air flow..!
I know it could be a problem trying to force the smoke down a flexi pipe into the smooth pipe then into the smoker but I thought it would be worth a try

Re: Using a fan to aid sawdust smouldering

PostPosted: Fri Feb 28, 2014 2:55 pm
by GUS
When you were a kid did they ever teach you how to "force" an open fire into life by means of placing a covering sheet of newspaper over the fire frontage so it was forced to consume existing fuel to catch? ..I think you need to start there, (point of ignition).

Make a temporary cover with cardboard or similar & gaffer tape to limit outside influences,
Q. when lit is it pulling smoke out of the (presumably open fronted) dust box, ..ever?

Any online manual for this unit?