Another keg furnace

I would think at those dimensions, a #10 is the biggest that should go in that furnace. It all comes down to having the space for your lifting tools to extend around the crucible and grab it. I would always plan for an oil burner and if you end up on propane, it just costs you a bit more in fuel. At least you'll have the space for a larger crucible. Don't agonize too hard over this, we all would have done things a bit different if we rebuilt our furnaces. I wouldn't build a rig for a #20 and then only use a #6, that's silly. I built for a #10 and use a #6 most of the time.
My bore is 11" across and my #10 measures 6 1/2 across the top.
Here is what it looks like with the tool sitting in there. I have about 1.5" of clearance on the sides. (yes, I think my furnace is about 5inches too tall. Not bad for my first build I think)

 

If you can draw it and take a picture of the drawing it might help.

If it's a lift off furnace why does it need a drain? (I'm learning)

 

Jason
That thing looks like an industrial accident. I am happy to say that as predicted the last exercise equipment my wife last brought home has been exercised.
How thick are the sides of your furnace?

Oldironfarmer
On the drain. It is because the burner will be in a channel that would be the low spot if a full crucible failed in the furnace. I plan on the pith covering the drain hole. This will be at the bottom of a sump. The thought is if the sump floods it will float the pith exposing the drain. With the cart there is room to put a ketch pan with some sand just in case.

Sorry for the lack of drawings and or pictures. I misplaced the camera at the shop the other day.

Joe

 

About 2" Joe. Kaowool has a tendency to compact down a bit when ya start ramming mizzou.

 

So things have been coming along slowly to say the least. The furnace is taking a back seat to all the summer repairs I have neglected.

I originally made the burner mold forum out of plastic and wood but decided that it just was not quite what I wanted. I then built one out of P.V.C and an inner tube but had problems holding dimensional shape. My third try is made out of Styrofoam with a plaster shell and sealer. It is by far the best but at this time a bit rough. After second guessing I cut the height down by 1 inch. I still have to put on the side tube part for the burner but it is close to being ready to cast in refractory. It will only be 3/4 inch thick on the bottom witch will make for a very hot bottom. I might end up setting it on an inch of wool.
The refractory

The refractory I bought off of E-Pay
Castable Refractory Cement, 45% Alumina Low Cement Castable, Accomon-45,12.5 LBS
$39.99 rated at 2822 F has particals the size of small pees and will not be suted for hot face.

Another minor slow down. After the Kaowool and refractory that about shoots this months hobby budget! I will order Satanist in a couple weeks if I can find it. I just hate to pay $45 for the refractory and $55 for shipping!
For now I hope that the 13 Lb. Is enough to cast t the burn chamber.
On the barrel, I plan on putting 1 inch of wool around the bricks. This will fill in the walls then pouring a ½ inch thick lip on each end to keep every thing centered and give a good surface for sealing the top and bottom to the barrel.
I got a new drawing pad the other day for the grand kids so I can play with it for 2 days before I give it up. I do hope it helps explain.
In the picture where after casting is, It is suppose to say burnt out after casting.

Joe

 

Thanks for the reply Kelly. You are absolutely right in that I do not have near enough refractory. In the beginning I had intended on just using the liner I had and patching the holes with the trimmings from cutting down the 14 inch liner.
Now I find that I have decided to expand the liner I.D. to 10.5 inches after coating with Satanite.
The filling of the spaces between the original liner to expand it took 4.24 Lb and although I probably would have enough to pour the top and bottom ring on the barrel of the liner to .5 inch. I have decided to just use what is left to pour around the disk of light refractory I already have for the lid. Filling in the space between the light refractory and the edge should pour out at around 1 inch and be fairly durable.
I will have to order more refractory for the bottom portion around the burn chamber and rim around the top and bottom of the barrel. What would you suggest I buy this time for refractory?
The 2 pictures are of the sides of the liner “barrel” and the lid. The barrel is mostly finished other than the planed rims to be poured on each end filing in the gap between the liner and keg along with a 1 inch wrap of wool. The final dimensions of this assembly “barrel” will be approx. 13 inch tall 10.5 I.D. fit to fill keg width.
The burn chamber.
The bottom with the burn chamber cast around the Styrofoam bowl will be 4.5 inch deep with the hollow chamber taking up 3.6 inch of that depth leaving room for .9 inch of refractory underneath. The bottom with of the burn chamber cast around the styrofoam bowl diameter is 10 inches the top is 10.5. The widest part of the chamber is 12 inches around the middle.
As you can tell I am not very skilled at explaining a 3 dimensional object, nor am I very skilled with a camera / video or paint programs. That’s pretty bad for someone who made a living in maintenance and electronics repair.
Can you pleas explain what part I am not explaining well and I will try to do better. I know it is a bit confusing. The project is modified often and sometimes without clarification.
Again thanks!
Joe

 

Thanks again Kelly!
I an about 70 miles from Indianapolis but I seldom make it out of town other than to go to the shop. I have had several seizures in the last few years, nothing life threatening and usually with a couple of seconds notice but they do cause total loss of conscious. So for the safety of others I do not drive except in an emergency and then only as far as required to get help or another driver. I will pay the $55 shipping if I must but I will complain about it!
I was glad you gave me the advice on looking up the curing of the refractory. I had seen several forum post on the slow razing of the temperature after the initial drying time but had forgot about keeping things at a very high humidity for the first couple days. I wrapped the barrel in wool tonight and placed it under a trash can with a bowl of water that will be in the partial sun for this time. It looks like it will be a couple of weeks before I can get the new refractory. This should give me some time to work on the cart and other parts of the furnace.
I finished the final shape of the burn chamber. I was lucky to find a plastic cup that i partially filed with plaster and attached to the doughnut. It is 2.7 tapering up to 3.2 inches. A 2 inch water pipe is just under 2.4 inches so there will be plenty of clearance.
One last question for the night. Where would be the best place to put the thermal couple? I am thinking through the side and ½ way through the refractory brick? Would this be advisable?
I will post a couple of pictures of tonight efforts. Again thanks to all that have helped along the way!
Joe

 

Looks like your thermocouple has a stainless steel shield. In commercial furnaces those protrude through the hot face and measure the air temperature inside the furnace. If you og part way through the brick you are only measuring the temperature at that point which will be cooler than inside.

 

Why measure that temperature at all? My furnace has one temperature. FRIGGEN WAY HOT. Not like this number will do you any good anyways. A kiln...okay... I measure that so I know when my shells are up to temp.

 

It is a K type so it could not take the internal chamber temperature. I just want it to adjust , somewhat monitor the burner efficiency by taking a wall temperature. The furnace will be on a role around cart, temperature monitoring is dirt cheep and I have a lot of room out of the way behind the heat shield. I just think for under $10 it could not hurt.
Joe

 

I was wondering if any one has used this refractory? SAIRBOND - 55 LB. BAG Refractory Mortar from HarbisonWalker International?


SAIRBOND - 55 LB. BAG Refractory Mortar
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Price: $88.50 & FREE Shipping
New (1) from $88.50 & FREE shipping.
Specifications for this item
Part Number 50005
Measurement System Inch
Brand Name SAIRBOND

I will be ordering a 55 Lb. Bag soon and was wondering if it could be used thin as in 1/4 - 3/8 over insulating fire brick as a hot face?
I will be casting the thicker parts of the furnace with it. The burn chamber and a couple of faces none of this will be thinner than an inch but if it will work. I would like to also use it as a thin hot face.

Joe

 

Ive not used it, but if given the option i would use mortar as mortar. Especially at that price. H-W has other products that are probably better suited as hotface if theyre available to you. Although Satanite is also a mortar and is being used successfully by some of our members, it is a high alumina mortar as opposed to sairbond which is fireclay based.

 

It will work for a hot face and thin sections.

I would not use it. It is a mortar and not suitable for heavy thicknesses. There are lots better products. Mizzou is common and good for making thick sections, but it is not a good insulator. Buy a little Satanite to use for a hot face, it is very easy to use and very forgiving. You really want the thick sections to be an insulating material. Sairbond and Sairset (pre-mixed) are for sticking bricks together and they do really well at that. They don't provide insulation. I think bricks laid loose work the best anyway. Expansion and contraction are going to crack something anyway, the seams between the bricks gives a place for that to happen. A hot face on top of 2,600F insulating brick makes a good furnace, and ceramic fiber behind that is even better. Satanite on ceramic fiber is probably the cheapest and best with a layer of insulating brick on the floor with Satanite on it. Thick Satanite is not good either. Paint it on in a few thin layers.

Another good hot face is Greencast-94. 94% alumina. Also not a good insulator. But it is good to 3,500F and great for plinths and tuyeres. But it requires an extensive dryout procedure to avoid cracking and spalling.

 

Thanks for the advice! I am very close now on having things together as far as the basic shape. I did make it to the shop yesterday to mostly finish the lid but still have to cast the burn chamber and a few smaller parts.
The heat made me a bit sick so I am taking it easy today.
Joe

 

Has anyone herd of these people and do you think it is a scam? It sounds way to good to be true with free shipping!
http://www.yibtrade.top/adhesives-sealers-c-1_8/mizzou-castable-plus-55-lb-bag-p-3454.html
Joe

 

Maybe it's only the bag.

 

After looking at the sight. I am more convinced that it is a scam! They sell everything from tape to toilet paper. All for around $20. They must have found that $20 is the magic number.
Joe