Corn stove and clinker problems

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ryanissamson

New Member
Dec 19, 2014
12
Indianapolis
Hey everyone,

I'm new to corn stove burning, but it's been a mostly positive experience so far. The one thing that's keeping it from being amazing is my experience with the clinker. The stove burns hot and seems to have little issues, but after burning about 18 hours, when I attempt to remove the clinker, there isn't anything completely solidified on the bottom. Instead, the layer on the bottom is softer like clay and the poker doesn't get underneath it but just digs into it. It'd be okay if the fire had no issues, but the pot eventually fills up and the fire dies. After dying, this soft layer hardens and forms a clinker, but it clings to the pot something fierce and I have to bust it apart into small pieces which takes about ten minutes. Currently, I'm averaging having to restart the fire completely every 24 hours which eats through starters pretty quickly.

In the past two weeks I have only had one successful clinker form and have removed it without issue.

Any help or wisdom would be greatly appreciated!
 

ryanissamson

New Member
Dec 19, 2014
12
Indianapolis
Something I'm going to try - although I'm not sure this will help - I'm going to sift the corn before putting it in the hopper to try and minimize dust or anything other than whole kernels. I'm wondering if the corn "dust" (partial corn bits and crushed grain) is messing things up.
 

hossthehermit

Minister of Fire
May 17, 2008
2,571
Maine, ayuh, by gorry
Got a few cornburners on here, one should be along soon .......... or message sidecarflip on here
 
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Bioburner

Moderator
Aug 4, 2012
7,318
West central Mn
Have you tried adding some ground oyster shells that they feed to chickens to the corn. Works for Countryside stoves well. About a cup to a bucket of corn. I add about a quart of pellets to a bucket of corn so the Bixby has no issues cutting a new biscuit. Have you contacted Nesco about how to remedy the problem ?
 

ryanissamson

New Member
Dec 19, 2014
12
Indianapolis
Have you tried adding some ground oyster shells that they feed to chickens to the corn. Works for Countryside stoves well. About a cup to a bucket of corn. I add about a quart of pellets to a bucket of corn so the Bixby has no issues cutting a new biscuit. Have you contacted Nesco about how to remedy the problem ?

I haven't tried any of that. I suppose I could get the oyster from tractor supply. Just to be sure, you're recommending trying to add a quart of wood pellets to a 55gal bucket of corn? I can try that as well.
 

Bioburner

Moderator
Aug 4, 2012
7,318
West central Mn
Quart of pellets to a 5 gallon bucket.
 

Bioburner

Moderator
Aug 4, 2012
7,318
West central Mn
Was recommended by another corn burner to keep the clinker from getting like a rock. The older corn varieties didn't seem to have as much of an issue. GMO problem? No access to lab anymore to try and figure out the makeup of the clinker.
 

ryanissamson

New Member
Dec 19, 2014
12
Indianapolis
Was recommended by another corn burner to keep the clinker from getting like a rock. The older corn varieties didn't seem to have as much of an issue. GMO problem? No access to lab anymore to try and figure out the makeup of the clinker.

Interesting. I'll give it a shot and report back.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Hey everyone,

I'm new to corn stove burning, but it's been a mostly positive experience so far. The one thing that's keeping it from being amazing is my experience with the clinker. The stove burns hot and seems to have little issues, but after burning about 18 hours, when I attempt to remove the clinker, there isn't anything completely solidified on the bottom. Instead, the layer on the bottom is softer like clay and the poker doesn't get underneath it but just digs into it. It'd be okay if the fire had no issues, but the pot eventually fills up and the fire dies. After dying, this soft layer hardens and forms a clinker, but it clings to the pot something fierce and I have to bust it apart into small pieces which takes about ten minutes. Currently, I'm averaging having to restart the fire completely every 24 hours which eats through starters pretty quickly.

In the past two weeks I have only had one successful clinker form and have removed it without issue.

Any help or wisdom would be greatly appreciated!

If you'd had sent me a PM, I would have replied.....

Take a coat hanger and form it into a loop that sticks above the burn pot, goest to the bottom of the bot and in the bottom, bend the legs at 90 degrees so each leg lays along the bottom of the pot parallel..... (so it makes a handle with the loop sticking up to grab a hold of.)

Harman's feed differently, Harman's push the fuel up toward the burn area and the burned fuel then drops off the burn plate into the ash pan.....

........yours has a pot, like mine, consrquently you need what I term a 'clinker hanger'.

Anyway, put the shaped coat hanger in the bottom of the pot, add some pellets to start the fire (pellets always start a fire better, less temperature needed for initial combustion, get her going with corn and allow the usual clinker buildup in the bottom of the pot. When the clinjer 'appears' of sufficient size, open the door, grap the hoop with your hand (in an oven mit or welding glove of course so you don't get burned) and lift the clinker with the clinker hangar up and tilt it at the same time so the burning corn on top, falls into the now, clean pot. remove the bisquit and close the door (takes about 15 seconds total).

You are now ready to make another 'bisquit'.

You still need to cleran the stove regularly but using a clinker hangar and forming a bisquit makes life more bearable.

For disposal, let it cool and pop it with a hammer or toss the whole thing. Coat hangers are cheap and one hanger makes 2 clinker pullers.

If the stove has an agitatir/stirrer, pull it. You don't need it with straight corn. Let the bisquit build without agitation.

Your pull interval will depend on corn test weight and how much you are combusting. I typically pull mine every evening and clean my stove every 2 weeks when running hard.
 
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ryanissamson

New Member
Dec 19, 2014
12
Indianapolis
If you'd had sent me a PM, I would have replied.....

Take a coat hanger and form it into a loop that sticks above the burn pot, goest to the bottom of the bot and in the bottom, bend the legs at 90 degrees so each leg lays along the bottom of the pot parallel..... (so it makes a handle with the loop sticking up to grab a hold of.)

Harman's feed differently, Harman's push the fuel up toward the burn area and the burned fuel then drops off the burn plate into the ash pan.....

........yours has a pot, like mine, consrquently you need what I term a 'clinker hanger'.

Anyway, put the shaped coat hanger in the bottom of the pot, add some pellets to start the fire (pellets always start a fire better, less temperature needed for initial combustion, get her going with corn and allow the usual clinker buildup in the bottom of the pot. When the clinjer 'appears' of sufficient size, open the door, grap the hoop with your hand (in an oven mit or welding glove of course so you don't get burned) and lift the clinker with the clinker hangar up and tilt it at the same time so the burning corn on top, falls into the now, clean pot. remove the bisquit and close the door (takes about 15 seconds total).

You are now ready to make another 'bisquit'.

You still need to cleran the stove regularly but using a clinker hangar and forming a bisquit makes life more bearable.

For disposal, let it cool and pop it with a hammer or toss the whole thing. Coat hangers are cheap and one hanger makes 2 clinker pullers.

If the stove has an agitatir/stirrer, pull it. You don't need it with straight corn. Let the bisquit build without agitation.

Your pull interval will depend on corn test weight and how much you are combusting. I typically pull mine every evening and clean my stove every 2 weeks when running hard.


Great! I'm new so I'm still learning the community. I am trying the hangar trick now and will let you know how it goes. I might need to make the hangar legs wider along the bottom, but I'll see if it works with how it is. I only had a small hangar available. Thanks again for the tip! I'll also pick up a bag of pellets when I'm at the store for starting the fire.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Great! I'm new so I'm still learning the community. I am trying the hangar trick now and will let you know how it goes. I might need to make the hangar legs wider along the bottom, but I'll see if it works with how it is. I only had a small hangar available. Thanks again for the tip! I'll also pick up a bag of pellets when I'm at the store for starting the fire.

Corn wise, the community here is a distinct minority. There are a few as well as a moderator (Bioburner)who roast corn but most on here are pellet burners. I suspect that will change as the corn versus pellet prices become even more attractive. Most pellet stoves can readily burn up to a 50% corn-pellet mix with no modification to the a/f ratio. Over 50% one needs to tailor the a/f ratio to a corn burn with more combustion air, run a modified corn pot and higher grade venting plus the maintenence, especially end of season maintenance becomes more critical.

I'm usually around (or Bioburner) if you have an issue or question.
 

hossthehermit

Minister of Fire
May 17, 2008
2,571
Maine, ayuh, by gorry
Hopefully the availability of corn at a reasonable price gets better here in Maine ............ that was one of the biggest reasons I bought the Revolution initially, the multi-fuel capability........ since I've had it, all I can find is pellets
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
Hopefully the availability of corn at a reasonable price gets better here in Maine ............ that was one of the biggest reasons I bought the Revolution initially, the multi-fuel capability........ since I've had it, all I can find is pellets


Corn is just as easy to package as pellets (in bags), even easier because nature does the processing, not machinery. You never know. here, living in a predominantly ag area, corn is almost 'underfoot' most of the time.

You do have something there, we don't have..... moose.
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan

Bioburner

Moderator
Aug 4, 2012
7,318
West central Mn
BTUs of corn is close to or better than pellets per pound. Density is more than pellets. Auger problems? Stuff flows better than pellets by far. Common issue with corn is that it needs to be below 15% to burn and store properly. I just made a small batch drier and getting it into single digits like pellets. Remember pellets are around 7-8% moisture.
 

Bioburner

Moderator
Aug 4, 2012
7,318
West central Mn
I took care of animals for a vet and he had a meat grinder powered by a volkswagon engine. Cop stopped by one morning looking for someone as we just starting grinding a whole calf. Nope didn't see him here. Moose might take a bit longer. So the answer how do you get a moose thru the auger, get a bigger auger. Wolves are eating all of Minnesota moose.:(
 
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SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
I took care of animals for a vet and he had a meat grinder powered by a volkswagon engine. Cop stopped by one morning looking for someone as we just starting grinding a whole calf. Nope didn't see him here. Moose might take a bit longer. So the answer how do you get a moose thru the auger, get a bigger auger. Wolves are eating all of Minnesota moose.:(

...and not at all on thread but along the above comment, I see the Washingtonians are going to make it illegal to hunt wolves (again), putting them (back) on the endangered species list which makes our wolf hunt here in Michigan (UP) illegal too. I see where the only way you can legally take a wolf (if this fiasco is signed into law) is if it's a direct threat to a human..... stock animals, or elk or deer don't count. What phooey. I was kind of looking forward to having an alternate animal to hunt in Idaho next fall..... Next will be song dogs, we are overrun with them here and they are a very wary animal to hunt.

I just don't get the rationale at all.

Back to regular programming.....
 

SidecarFlip

Minister of Fire
Feb 7, 2010
5,273
S.E. Michigan
BTUs of corn is close to or better than pellets per pound. Density is more than pellets. Auger problems? Stuff flows better than pellets by far. Common issue with corn is that it needs to be below 15% to burn and store properly. I just made a small batch drier and getting it into single digits like pellets. Remember pellets are around 7-8% moisture.

A great synopsis, I'd like to add some additional information, some I've stated before, some not. At my age, I do repeat myself ocassionally....==c

The ability of corn to produce heat by oxidation is directly dependent on what farmers refer to as 'test weight' The higher the test weight is (test weight is based on 15% RM corn btw), the better the corn will be at producing heat from a given quantity. You want corn ideally to be in the mid 50's test weight, again measured at 15%RM.

Corn needs to be below 15% RM to combust readily. Corn from the field is not an ideal fuel for a biomass burner, one, it's dirty (has trash like stalk and cob parts intermixed with the kernals, it needs to be cleaned corn without trash. You can buy a corn cleaner which does a good job or you can buy cleaned feed corn, I go with the latter myself. Corn from the field can be anywhere in RM and test weight, typically harvested corn in this area was coming off above 20% RM. Thats way too high to ignite. To burn readily, corn needs to be in the 12 -14% range. Below 12 it tends to burn too quickly.

Corn always flows (through a stove auger better than any pellet will). Mother nature grows very uniform kernals, unlike pellets that can be odd lengths. Nice thing about modern biofuel stoves is almost every one of them will readily combust corn in a mix with pellets, up to 50% corn and 50% pellets and it's very possible to take off brand, low grade pellets and mix in varying ratios of corn and obtain really good heat output. Along those lines, at ratio's above 50-50 to straight corn, the stove has to be specifically designed to burn corn, usually with adjustable combustion air settings and a burn specific pot for corn, though some stoves come set up for pellets and already have a corn pot with additional holes that allow extrta combustion air to flow through the fuel bed.

Because corn combusts (carmelizes) at a much higher temperature than wood pellets, when initially starting a stove on straight corn, pellets should be used to establish the fire and then corn augered in on top of the burning pellets to readily ignite. In mix ratio's below 50 -50, you can start the fire in thye normal way (igniter or gelled fire starter.

Corn prduces a different ash than pellets. When corn combusts (or carmelizes), the inner portion of the kernal or the meat, oxides and gives off heat, while the outer shell turns to 'ash' or what you see in the pot. That ash forms a clinker (or clumps) and that has to be removed periodically, just like the ash from the pellets does. Some designs handle the clumps (clinkers) better than others.

Finally, because corn produces trace amounts of nitric acid vapor as a by product of combustion, the venting has to be rated for pellets and corn. Pellet only venting is a lower grade of stainless (liner) and can eventually be impacted by the nitric acid vapors. Additionally, the stove itself must be maintained at the end of the season with careful cleaning (as well as the venting) to remove all traces of ash that can attract moisture during the warmer moinths and turn to an acidic mass that will corrode the internal parts of the stove and/or the venting.....

There are of course, more finer points (as with anything) but the above generalizations are a good yardstick.
 

mithesaint

Minister of Fire
Nov 1, 2011
512
NW Ohio
BTUs of corn is close to or better than pellets per pound. Density is more than pellets. Auger problems? Stuff flows better than pellets by far. Common issue with corn is that it needs to be below 15% to burn and store properly. I just made a small batch drier and getting it into single digits like pellets. Remember pellets are around 7-8% moisture.

Do you have any pics or details of the dryer? Corn is 1/2 the price of pellets here, but I can't find any lower than 15% moisture, and it's tough to get going sometimes, and doesn't always store perfectly. I'd love to burn some 11% corn, but i'd have to dry it myself.
 
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