One Burner 10 Cubic Ft Gas Kiln?

[Michael murphy]

 

That’s correct I’m in the US. I wish you well in your endeavors

[Mark C.]

My 12 cubic gas has 6 burners -its an updraft-one seems to little for any kind of even fire. how about two?

[tomhumf]

I'm still procrastinating about building this kiln, I really could do with a bigger kiln...

I have two questions that are bugging me. 

1. Should the door be 9" thick like the rest of the walls? Looking at the kiln book and other photos I looks like most people just use 1 layer,  4½" thick of brick on the door?

2.  I've decide to do 4½" thick arch for roof with fibre over the top.

Should the arch go over the whole length of the kiln, or just the internal space - I've tried to draw what I mean. The end walls on top option are build higher than arch. The lower option the end walls are cut to fit under the arch. 

[Magnolia Mud Research]

Go have a look at
Hank Murrow's fiber kiln (and conversation maybe with him)
http://www.murrow.biz/hank/ 
Hank is an expert on kilns, especially fiber ones.  

LT

[neilestrick]

To get the best seal between the arch and the back wall, put one layer of the wall under the arch, and one layer outside the arch. At the front it all depends on how you're doing the door. If there's a partial wall on each side of the door, then do the same, with the inner layer under the arch, and the outer layer outside the arch. If the door is going to be right up against the end of the side walls, then bring the arch flush with them.

You can probably get away with a 4 1/2" thick door, but if you build the door frame with 4" angle, you can put a layer of 1" rigid insulating board behind the brick, which will help a lot. If you're just stacking the door each time, then go ahead and make it 9" thick.

[tomhumf]

I got the first load of bricks delivered for this today. I've ordered arch bricks and enough for the base and a couple of wall levels with spares to cut the arch ends. I'll order the rest when I've go the tricky bits sorted. 

I'm going to try it with one burner to start and if it's not good I'll rebuild it with another burner. 

The outer footprint will be 45" X 40.5" and 34.5" tall to the skewbacks. I may make it taller in the future depending on how my working schedule is.

The chimney will be around 7 ft. I'm going to do one layer of arch (4.5") with blanket over the top and 9" thick walls, floor and door. 

I need to order the angle iron for chimney and sides of kiln and threaded rod. I'm thinking 3mm thick 2" angle iron and 10mm threaded rod would be ok for this size kiln? 

I would like some connectors like in the image for the rod but can't find anything like it. I may just use angle irons horizontally with holes drilled for the rod on sides of kiln to hold it together. I will need angle to hold the skewbacks in place anyway. 

For the chimney I may just use wire with turnbuckles to hold the angle iron together like I did for my little kiln. 

[Fred Sweet]

Tom-

Don’t over think your connectors. Piece of steel pipe (ID to fit your rod) cut into sections and welded to your angle iron.

Regards,

Fred

[Bill Kielb]

As long as we are welding, clip angles, threaded rod and jamb nuts always were easy. Stainless threaded rods, nuts and washers look nice without much care.

[tomhumf]

2 hours ago, Fred Sweet said:

Tom-

Don’t over think your connectors. Piece of steel pipe (ID to fit your rod) cut into sections and welded to your angle iron.

Regards,

Fred

Right, that's the thing I was hoping to get it done without welding. I don't have a welding set and don't really want to buy one or pay for it to be done by someone else. 

But it does make it a bit of a headache without welding, do maybe I'll have to get a set. I'm mainly worried about making terrible welds and electrocuting myself. 

[Bill Kielb]

3 hours ago, tomhumf said:

Right, that's the thing I was hoping to get it done without welding. I don't have a welding set and don't really want to buy one or pay for it to be done by someone else. 

But it does make it a bit of a headache without welding, do maybe I'll have to get a set. I'm mainly worried about making terrible welds and electrocuting myself. 

Ahh I see, got it.
Drill and screw then.  How about pre drill clip angle and pilot drill  corner angle? Maybe # 12 zinc or stainless. Two screws per clip? Can get reg head, or square head probably less hassle. #10 and greater are usually good for over 2000 pounds in shear. Two screws, 4000 pounds in sheer without friction that is. Should last a long time.

 

[Magnolia Mud Research]

Tom,

try this idea:

Make a clamp to hold the angle iron: use a threaded bar with a pipe tee slipped over the bar at each end; a big washer and a nut on each end to compress.  

see sketch.  blue is the threaded bar, red is the pipe tee, black washer, brown is the nut, green is the bricks with angle iron at corners to be clamped. 

 

LT

[tomhumf]

Ok thanks both. Bill do you mean something like this and screwing it to the angle iron ? 

https://www.worktop-express.co.uk/worktop-accessories/worktop-fixings/corner-bracket-25-25-1point6mm-10?gclid=CjwKCAjwwMn1BRAUEiwAZ_jnEgpzm6Iu_aZHi0-R528k6ORsR6FpHpvOg6vtQ5E5ZGtwDLl-S1VnlRoCZYoQAvD_BwE

 

LT, did you mean a threaded rod going the other way too? I think I'd be worried about it popping off. 

I've had an idea to get some 3mm X 30mm flat bar and bend it like this into a zigzag, and drill holes for threaded rod. Could work? 

 

[neilestrick]

9 hours ago, tomhumf said:

Right, that's the thing I was hoping to get it done without welding. I don't have a welding set and don't really want to buy one or pay for it to be done by someone else. 

But it does make it a bit of a headache without welding, do maybe I'll have to get a set. I'm mainly worried about making terrible welds and electrocuting myself. 

It's really difficult to electrocute yourself while welding. Burning your eyes is more of a risk. All you need is a little gasless wirefeed 'buzzbox' that runs on 120 volts. They work fine for building kilns, and you'll find all sort of other projects to use it on. Not the prettiest welds, but strong if you do it right. I've built several kilns with mine. They generally only have 20-30% duty cycle ratings, so you can only weld a minute or two at a time, then let it cool. If you cut the piece, then weld, cut then weld, you can move along at a pretty good pace.

[Bill Kielb]

First thing that came to mind was to make the clips out of the same corner angle and just bolt everything together. Short # 10# self drillers will bore into the brick 1/4” so  drill the clips clear and small pilot hole in the corner angle if the self drilling screws don’t make it on their own. I am not a fan of bending heavy stuff although it is  a cool idea. Just hard to bend  heavy iron if you don’t have the tools. I am assuming the corner angles are going to be something like 1-1/2 “X 1-1/2” x 3/32”. 
Just one idea.

[tomhumf]

Thanks Bill yes that's what I was thinking you meant. 

After some thought I've decided to go the welding route. I will use pipe like Fred suggested welded on to the angle iron. 

I think the welding will be less if a headache than all the cutting and drilling otherwise. I may also have use for welding in future projects like you said Neil.  

[Bill Kielb]

43 minutes ago, tomhumf said:

Thanks Bill yes that's what I was thinking you meant. 

After some thought I've decided to go the welding route. I will use pipe like Fred suggested welded on to the angle iron. 

I think the welding will be less if a headache than all the cutting and drilling otherwise. I may also have use for welding in future projects like you said Neil.  

Not hard, tack weld, point the electrode at what you want to penetrate. You tube videos. Good choice! Add a little protection after, (Cold galvanizing spray on welds and paint)   should last a long time. The pipe tees are cast and round so virtually only need a nice neat filled tack  or well placed neat stitches. You will do fine. Besides as long as you are welding you could  tack angles up as well if you have trouble with the tees.

[tomhumf]

I'm just working on the chimney connection, angle iron hasn't arrived yet but it's 2" wide (represented by the piece of stick on photos).

I'm planning to set the chimney apart by 3", so the angle iron will fit fine above the connection point. 

I'm just not sure how to do the connecting bricks. I could keep the flu 6" X 6" but I'd have to cut the connecting brick really thin to fit the angle iron in ( bottom photo) . I could make the flu 4" wide and 9" tall which would mean less of a cut into the connecting brick ( middle photo) 

Maybe there's a more simple way I don't see where I can keep the bricks full thickness? 

[Sorcery]

Make the chimney bigger!

Better to spend a week on brickwork now than wishing you had when that ten cone won't fall.

I've read a lot of things where that simple square isn't enough.

I've welded roof sheets down in the rain thru 2inch puddles. No worries! That galvanized smoke'll kill yah though!

Sorce

[tomhumf]

Hmm, it's only going to be about 8 cu ft total interior so I'll try this size chimney first. It's going to be all loose stacked anyway so can change if needed. 

I'd still have the same problem joining around the angle iron if it was bigger though.

[tomhumf]

I'm giving this the first bisque firing, I decided to make chimney 9" x 6" interior. Still using one burner. I made the arch and door double thick bricks in the end. 

It seems to be struggling to climb a bit, it's going best when chimney damper is only open about 1.5" which seems weird, it's at about 600C after 5 hours. 

Maybe I should build chimney up more in angle irons?

[tomhumf]

Chimney damper during building

[Bill Kielb]

47 minutes ago, tomhumf said:

I'm giving this the first bisque firing, I decided to make chimney 9" x 6" interior. Still using one burner. I made the arch and door double thick bricks in the end. 

It seems to be struggling to climb a bit, it's going best when chimney damper is only open about 1.5" which seems weird, it's at about 600C after 5 hours. 

Maybe I should build chimney up more in angle irons?

How many BTU do you have?
Let’s get a picture of your flame to make sure it is reasonably oxidized at various pressures.

how big is your secondary air opening? (Likely inky the space around the burner)

making the chimney taller will make it extract more heat but at the same time if it’s struggling for secondary air your flame is inefficient but to get any heat you need your current almost fully blocked.

We probably need a bit more info to speculate

 

[tomhumf]

This is what I have on BTU : not really sure about that

Regarding the burner, I got this reply from supplier: 

BTU ratings as follows:-

3 psi 82,750

10 psi 151,100

30 psi 261,700

My regulator goes up to 2 bar so I guess in theory I could get 261,700? I never currently turn it up that high though. 

I couldn't really get a good pic of flame, burner hole is 4.5" x 3". 

Kiln is at 777C now

 

 

[Bill Kielb]

13 minutes ago, tomhumf said:

This is what I have on BTU : not really sure about that

Regarding the burner, I got this reply from supplier: 

BTU ratings as follows:-

3 psi 82,750

10 psi 151,100

30 psi 261,700

My regulator goes up to 2 bar so I guess in theory I could get 261,700? I never currently turn it up that high though. 

I couldn't really get a good pic of flame, burner hole is 4" x 3". 

Kiln is at 777C now

 

 

What pressure are you at currently?

[tomhumf]

Just under 0.5 bar it looks like, kiln is at 850C.

I'm pretty sure it will make bisc temp, just wondering how it will cope with a cone 7 reduction firing. Seems really strange it fires best with chimney only and inch open. Not sure how easy it will be to get it to reduce.