# Terracotta chimney liner for microwave kiln ?



## yonderfishin (Apr 8, 2012)

Anybody know if this would work or have any experience with it ? It is clay/ceramic and should withstand heat but would it take "enough" heat or fail during the process ? Im just thinking of making my own microwave kiln for smelting black sand and going over possible choices of materials other than ceramic fiber board that can be expensive and usually not obtained locally , or firebrick which I have read will work but its weight makes it not ideal. It occurred to me that chimney liner might have some value as an option , but other than it being made of fired clay I dont really know a lot about it. Any thoughts ?


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## DONNZ (Apr 8, 2012)

Sounds dangerous. 

One in your area? If you do they have walk in. 
Rebuilding web page but can look at products they carry. 
They are reasonable on cost.

½" X 2' X 4' " Duraboard" with tax was around $54.00. Carry 1" thick board. 

They also carry Insulating Firebrick.


THORPE PRODUCTS COMPANY

http://thorpeproducts.com/about.htm


Thorpe Products provides comprehensive geographic coverage through its 10 branch network which includes 4 locations in Texas - Houston, Dallas, Beaumont and Corpus Christi, 2 locations in Louisiana - Gonzales and Lake Charles and locations in Mobile, AL, St. Louis, MO, Little Rock, AR, and Memphis, TN. Additionally, Thorpe has a dedicated international team that focuses exclusively on providing cost-effective solutions to our customer’s insulation and insulating refractory needs.


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## yonderfishin (Apr 10, 2012)

DONNZ said:


> Sounds dangerous.
> 
> One in your area? If you do they have walk in.
> Rebuilding web page but can look at products they carry.
> ...





I am trying to find a supplier for duraboard or ceramic fiber board in my area ( Toledo Ohio area ) but Im not having much luck yet. I really dont know exactly what to search for on the internet. I found a couple companies but I think they are only suppliers for large industry. In the meantime , firebrick or chimney liner looks promising , so Im just trying to see if anybody out there has experimented with it. 

Seems like , a section of chimney liner with some type of insulation between it and the crucible would work but Im dealing with a lot of unknowns and variables so I dont know. 

Any other ideas on materials to use for the kiln ?


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## etack (Apr 10, 2012)

http://myersfireplaceandpatio.com/?page_id=114

ask them if they build fireplaces they will have what you need.

Eric


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## galenrog (Apr 15, 2012)

Terra Cotta does NOT provide the thermal insulation necessary for use in a microwave and will actually flake with repeated use in this environment. All the home gamers I know who have built their own have used fire brick and cut it to size with a masonry saw.


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## yonderfishin (Apr 15, 2012)

galenrog said:


> Terra Cotta does NOT provide the thermal insulation necessary for use in a microwave and will actually flake with repeated use in this environment. All the home gamers I know who have built their own have used fire brick and cut it to size with a masonry saw.




Thanks galenrog , thats pretty much what I thought but was a little curious about it. 

Anybody with experience with the microwave kiln ,....the commercially available kiln lists a kiln shelf as one of its parts , anybody know what function a kiln shelf serves in this situation and if it is a necessary part of the process ? Seems like the wave energy + material should cause the heat and all it needs is thermal insulation to reach desired temperature , ...unless I am missing something , a "kiln shelf" might be a component without a purpose.


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## Smack (Apr 15, 2012)

Kiln : http://detroit.craigslist.org/mcb/for/2958158566.html

http://detroit.craigslist.org/okl/art/2890550409.html

http://detroit.craigslist.org/okl/for/2923982104.html


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## DONNZ (Apr 16, 2012)

yonderfishin:

Throwing out some thoughts here:

Lowest cost that I can come up with:

Try: http://www.budgetcastingsupply.com/index.htm

Free shipping on a lot of items. But searching you may find ceramic blankets cheaper.

Chimney liner or fire brick in a square stack lined with a ceramic fiber (sample pic of a lining) Plus one badass homemade propane burner would be low cost.


http://backyardmetalcasting.com/

*The burner plans and diagram:*

http://backyardmetalcasting.com/oliverburner1.html

experiments: From common plumbing parts you can build burners to melt any metal from lead to iron.

*Oliver-upwind propane burner*


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## DONNZ (Apr 17, 2012)

Thinking about what you were saying this morning.

I was intimidated by the pictures on Thorpe Products website. A big complex and I'm just one person wanting one fiber board. I feel a bit dumb but I got up the courage to call and found they had a walk in counter.

Still a bit intimidated but I drove over there only to find a warehouse with a front office.


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## yonderfishin (Apr 18, 2012)

DONNZ said:


> Thinking about what you were saying this morning.
> 
> I was intimidated by the pictures on Thorpe Products website. A big complex and I'm just one person wanting one fiber board. I feel a bit dumb but I got up the courage to call and found they had a walk in counter.
> 
> Still a bit intimidated but I drove over there only to find a warehouse with a front office.





Cool. Unfortunately they dont have a branch location in my area. I was in contact with another company that is in the area by email and once they found out the small amount of product I was interested in they stopped replying. Thanks for all your help though.


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## DONNZ (Apr 25, 2012)

http://www.microwavegoldkiln.com/instructions

PLEASE READ ALL INSTRUCTIONS THOROUGHLY

MICROWAVE GOLD KILN


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## Palladium (Apr 25, 2012)

I like how he does the whole video showing everything in detail except how the microwave part works. Rotfl 
Ain't that what the whole thing is about?



[youtube]http://www.youtube.com/watch?v=tB3oQeTG-Mc[/youtube]


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## DONNZ (Apr 25, 2012)

http://www.microwavegoldkiln.com/instructions

It's in the instructions. If you need help with the flux email him, he's willing. A good description of your pay dirt would be in order. 

He might like this site for exchange of ideas and to field some questions.

He carries all the supplies.

and has:

http://www.microwavegoldkiln.com/faqs

Question: What does microwave transparent mean?
Microwave transparent means that the microwaves travel through the material, rather than bouncing off or heating it. It is important that the kiln material and kiln shelf and crucible are microwave transparent, so that the heat occurs inside the crucible, rather than outside it. If the heat occurs outside of the crucible, it then becomes a radiant heat, rather than a form of plasma arc within the crucible.

Another site to check out:

http://www.clay-king.com/

Don't know if they have what you need, but the prices seem fair.

Just messing around looking for:

Two searches: 

ceramic fiber board or refractory board 

Kiln repair (in your area)


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## yonderfishin (May 12, 2012)

Okay , I am about ready to give up on the microwave style furnace , locating the materials locally without having to order them sight unseen just seems impossible. Thanks for all the help you have given me so far though.

Does anybody know of plans to make an affordable and relatively simple to build propane or charcoal furnace out of brick that is capable of reaching temps high enough to smelt gold from black sand or pyrite ?


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## jimdoc (May 12, 2012)

You can get ideas from here;

http://www.backyardmetalcasting.com/gallery.html

http://www.backyardmetalcasting.com/index.html


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## yonderfishin (May 15, 2012)

jimdoc said:


> You can get ideas from here;
> 
> http://www.backyardmetalcasting.com/gallery.html
> 
> http://www.backyardmetalcasting.com/index.html





Thanks for those links , I seen that website before but completely forgot about it. I bought a small metal 6 gal. trash can with lid today that I plan to make a charcoal fueled furnace out of as soon as I get some refractory cement. Seems simple enough to make and should get hot enough if I do it right I think. I dont know how the crucibles will hold up being surrounded by charcoal but I guess I will find out.


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## DONNZ (May 17, 2012)

Just throwing this out there as general info: 

Paragon makes one of those microwave kilns. 

On sale with free shipping and no tax.

*Paragon MagicFuse Microwave Kiln*
http://www.paragonkilns.com/current%20specials.htm

Don't know if one can run it hotter, but at that other site they do sell the crucible and the super duper flux.
Running hotter might mean just raising it closer to the transmitter using a Pyrex pie dish, a round one upside down. This is all guesswork on my part, I have no clue.


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## modtheworld44 (Aug 16, 2012)

yonderfishin said:


> jimdoc said:
> 
> 
> > You can get ideas from here;
> ...



Hi Yonderfishin

If its not to late , I have a place here in chattanooga Tn were I got some porcelain blanket for pretty cheap.Its rated 2100-2300F and can handle a straight full blast propane torch pretty good.I got a 5-6ft long x 11/2-2 wide x 2 inches thick piece for about $10.I'm going to try making a microwave kiln with some as soon as I get a good watted spare microwave.

modtheworld44


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