JABOD questions

[ac160]

I have been digesting a multitude of JABOD threads and was considering building one to try out and wanted to run my idea by you all.  I am looking for clarification on a few things as well.

Basic info:  I am looking for ease of setup/tear down and storage.

Planning on using charcoal and/or trying corn.   Has anyone tried corn in a JABOD?  I am not sure about trying coal out yet.

My air supply will be a canedy otto blower.  On the tuyere should I was thinking a 1in pipe or should I downsize to 3/4 in.?   With that blower would it be better to have a slightly bigger tuyere as to not restrict airflow or reduce from 3 in to a 1 in pipe? Does schedule 40 or 80 work better?  It seems like it is a tossup from my reading on 40 or 80.  I plan on having it a around 12 in or so from the outside of the container to minimize heat transfer.

Also it sounds or looks like the tuyere needs to be located about a firebricks width above the bottom of the firepot, correct?

Contents of the container will be made up of kitty litter and the firepot out of firebrick to easily change size.  The firepot size will be about one firebrick.  If I would use corn or coal would it need to be deeper?

For the container holding it would it have to be a box?  I was thinking about cutting a piece out of one of the two items that are attached.  The center-auger (first picture)has about a 13 in diameter and I could cut it in half and add ends to it.  In the picture labeled unloading(second picture) is about 8in deep and about 8.5 in wide.  Either would need to be set on a table.

 

I feel like I am forgetting something here, but not sure what.  Thanks in advance for your help. 

 

 

 

I forgot to add the that most all my stock size  would be  around 1/2 in rod for learning with a max of 1in for experimenting if time allows.

 

[Frosty]

Using a hand crank blower means it doesn't make any difference what size the tuyere is. You could plug the output of that blower completely and crank it till the gears wore out and it wouldn't care. It's what is known as a "Transparent" pump meaning there is no solid force to moving air or liquids, it's a fan. If it were a piston pump or Roots type blower and you blocked the output it would either stall the motor or blow itself to pieces. These are called "Opaque" there is no free movement through it. 

Sorry to digress, your hand crank blower will work just fine whatever size tuyere you use. 

The rest sounds like it'll work okay and if it doesn't you can rearrange it till it does. 

Frosty The Lucky.

[pnut]

Sounds like it should work fine. My setup is a kettle grill filled with dry kitty litter and a firepot made from clay bricks. The firepot depth in the front and rear is the thickness of a red clay brick on it's thinnest side . It's a measurement that my brain just can't seem to retrieve anymore. It's ~2.25in? I have bricks on one and sometimes both sides to keep the fire deep enough. It's basically the same firepot design as Charles' MARKIII jabod post except when possible I prefer tall walls on both sides of my firepot. 

Your blower will work fine with a 3/4 or 1in  schedule 40 pipe. I have mine rigged up to attach to a one inch pipe with expandable dryer ducting.  You'll have to turn the crank fairly slowly or you'll blow all the fuel out of the firepot. They take some tinkering with to get them dialed in but after you figure it out it's easily repeatable. 

Pnut

 

[ThomasPowers]

Note that saying you have a Canedy Otto blower is rather like saying you have a Vehicle made by Ford; it doesn't indicate if it will hold 16 people or if it will hold 2 people.  So asking about  sizes of components to use with it is rather useless.

In general I like a large air transfer pipe that may neck down to a smaller one right when it goes into the forge.

The JABOD is trying to mimic the "hole in the ground type of forges" that have been in continuous use for around 3000+ years.  (But raise it up to a comfortable using height as most of us don't work squatting anymore.)  So anything that works is OK.  With a metal shell you don't need as much insulation as you do with wood---IFF it's mounted so it can't catch things on fire.  I often suggest people find a junked propane grill and make it into a JABOD forge---using vermiculite as the bed you put the dirt over can lighten it up a lot and a closable lid makes storing it outside easy too.

[ac160]

Frosty -- Thanks for the correction.  I was thinking more along the lines of "Opaque" when I was writing it.

Thomas --I should have been more specific.  The blower is a hand crank royal western chief that was my great grandfather's.  I will reduce it at the forge.  

[Irondragon Forge ClayWorks]

23 hours ago, ac160 said:

For the container holding it would it have to be a box? 

It doesn't have to be a box, however the items pictured would not be my choice, too narrow to suit me. I like a minimum of 24x24 inches. JABOD boxes are literally everywhere. For instance old sinks,push lawnmower decks, washtubs, the list goes on and on. I'm in the process of making one out of an old water pressure tank base.

[Charles R. Stevens]

So 3/4” schedual 40 gives you just about 7/8” wile schedual 80 is almost 3/4”.  3/4” schedual 40 or 1” schedual 80 will work well for charcoal and coal heating up to 1” stock. If you are only using coal you can go larger and place the tuyere farther below the hearth to tackle larger stock. 
not that the Mark III is intended as a demo forge and I have melted fire brick using a blower.