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silentC
11th Apr 2007, 04:59 PM
I've got this book by David Gingery in which he describes how to make a charcoal-fuelled furnace for melting aluminium. I'd always assumed that charcoal was that black lumpy stuff left in the bottom of the fire, at least that is what I have always called it, however it seems that charcoal is not that simple to make. Does anyone know anything about it?

Grunt
11th Apr 2007, 05:04 PM
A quick google brought up this. http://www.twinoaksforge.com/BLADSMITHING/MAKING%20CHARCOAL.htm

Didn't seem overly tricky.

silentC
11th Apr 2007, 05:08 PM
Yeah I read about that method but what I want to know is whether it's the same stuff chemically as what is left in the fire? Can I use it the same way? I suppose the best way to find out is to try it.

watson
11th Apr 2007, 06:46 PM
G'day Silent,
I make it in a 44 with a lid and a vent control.......I shovel dirt to cover the vent..next morning..charcoal. I guess the stuff in the bottom of the fire place is basically the same stuff.....just there's usually not a lot of it left at our place

I know this is a bit sacreligious to the purists.......but when I run out of charcoal......I use BBQ heat beads in both the foundry and the forge.......sparks a bit...but it works

Andy Mac
11th Apr 2007, 07:51 PM
Hi Silent,
I think its the same stuff, just the efficiency of producing it makes the difference. There does seem a difference in texture or density between some charcoals, maybe to do with the type of timber but also technique..amount of oygen left etc. I've used the black bits left on burnt logs after a bushfire and it seemed to work OK.

Cheers,

joe greiner
11th Apr 2007, 11:12 PM
The late Dave Gingery lived in Missouri USA. Upover here, newer BBQ's use propane, but lots of older ones, using charcoal, are still around; still being sold too:
See http://www.weberbbq.com/bbq/pub/grill/charcoal/

The charcoal is available in bags at supermarkets, and likely other places. That's the stuff Dave was writing about. I think one of his bookshops, Lindsay Books (http://www.lindsaybks.com/) has a book on making charcoal; might even have been by Dave.

[Reading Lindsay's catalog is a hoot, BTW.]

Joe

Edd
11th Apr 2007, 11:37 PM
As for left-overs-from-fire vs "charcoal", I doubt it's the same stuff. If you simply burn wood, you're left with ash which I don't think can provide much energy as it's already burnt up.

Charcoal can be simply made by placing a pine cone or balsa wood scraps, sawdust, etc in a can, punching a hole in the lid and cooking until smoke stops escaping the hole. This takes hours. THEN allow it to COMPLETELY cool, in which case the charcoal is ready. The idea is to minimize oxidation.
Alternatively you can buy it by the 3KG at bunnings.

EDIT: Heatbeads are more efficient than classic charcoal, so maybe they would be better?

snowyskiesau
12th Apr 2007, 12:25 AM
I think the charcoal that you find in a left over fire is basically the same stuff. It results from incomplete burning of the timber fuel.
If the fire was more efficient, there would only be ash.

silentC
12th Apr 2007, 09:18 AM
OK thanks. It was just something I was pondering as I was reading the book. When he said 'charcoal' I automatically thought of the black lumps that you find in the bottom of your campfire, and since we regularly have a backyard bonfire here, I thought I might have a use for it. I'll give it a go when I get the chance.

I'll also get hold of a drum with a lid and give making it myself a go. Wonder how it goes with hardwood?

I'd be surprised if I could buy it around here, but you never know. I grew up not far from a briquette factory but that was years ago and hours away from here. I can imagine the looks and comments I would get if I went to the local Mitre 10 and asked for a bag of charcoal. Doubt there'd be any use for it around here.

Did think about heat beads, but they cost money.

Bodgy
12th Apr 2007, 09:28 AM
I know this is a bit sacreligious to the purists.......but when I run out of charcoal......I use BBQ heat beads in both the foundry and the forge.......sparks a bit...but it works

When I built my forge I tried heat beads first. I found that not only did they burn out too quickly but the heat was not sufficient.

I now use some form of coal slag (courtesy of Ashore) and that is brilliant. I can melt steel in minutes and watch it drip out of the tuyere!

Silent

I you're in Sydney, let me know and I'll give you a 25 litre container of the stuff. Ashore was very generous.

silentC
12th Apr 2007, 09:35 AM
Not in Sydney but coming up in a couple of weeks. I'll see if I can fit in a visit to Turramurra!

Zed
12th Apr 2007, 09:43 AM
drop by my place and bring the bodge (5 mins from my place) , Ill make yers both a coffee - or a beer...

silentC
12th Apr 2007, 09:57 AM
But Turramurra is miles from Taronga!! :U

I'll see what I can do. Weekends are both pretty full and weekdays probably no good for you blokes.

journeyman Mick
12th Apr 2007, 10:10 AM
drop by my place and bring the bodge (5 mins from my place) , Ill make yers both a coffee - or a beer...


How quickly can you make a beer? I obviously haven't kept up with developments in home brewing.:D

Mick

silentC
12th Apr 2007, 10:13 AM
He didn't say we'd get to drink it!

Schtoo
12th Apr 2007, 10:33 PM
So, you got that sorted at least. :)

Another option if you happen to get roped in by the melting bug is a burner, either gas or liquid fueled. Problem is that the charcoal furnace Uncle Dave describes doesn't work too flash with a burner.

I think I will end up making a waste oil burner soon since the kero jobbie I have isn't as 'easy' as I would like it to be. The kerosene burner is good, but it's just a bit of a pain. With any luck, I should be able to get a waste oil thingy to work without needing a degree in thermodynamics to drive the thing.

Propane/LPG is by far the most user friendly, but you pay for that with your wallet.

Interested?

(Oh yeah, just quietly I am re-making my lathe. Just a tad bigger than Mr. Gingery's one, like about 50% and heavily modified. Finished about half the patterns, and some more siple ones to go, but some will hold of until I cast what I got. Thankfully, ally isn't a problem anymore. :D )

watson
12th Apr 2007, 10:40 PM
G'day All,
Propane in this present day costs a heap.....it's up to you guys but a google on Babington Burners could give you a new perspective on waste oil burners.
Sump oil......fine orifice........air pressure.....melt metal.

forge
12th Apr 2007, 10:47 PM
So, you got that sorted at least. :)



I think I will end up making a waste oil burner soon since the kero jobbie I have isn't as 'easy' as I would like it to be. The kerosene burner is good, but it's just a bit of a pain. With any luck, I should be able to get a waste oil thingy to work without needing a degree in thermodynamics to drive the thing
Propane/LPG is by far the most user friendly, but you pay for that with your wallet.
Interested?
(Oh yeah, just quietly I am re-making my lathe. Just a tad bigger than Mr. Gingery's one, like about 50% and heavily modified. Finished about half the patterns, and some more siple ones to go, but some will hold of until I cast what I got. Thankfully, ally isn't a problem anymore. :D )
I'm interested in your experiments with the used oil burner(have 4#44's full of it,it would be good to use them up)Which lpg burner plans have you got?I have Mike Porters book-on self aspirated lpg burners for forges and furnaces,regards,
Here is a link to the book >http://www.amazon.com/Gas-Burners-Forges-Furnaces-Kilns/dp/1879535203

watson
12th Apr 2007, 11:00 PM
G;day Forge,
Same book...built #1 and #2.........but I can't afford to run them.
Haven't built a Babington Burner yet...but it seems like the way to go.
Still using charcoal and on non-pension weeks.......BBQ heat beads

forge
12th Apr 2007, 11:38 PM
G;day Forge,
Same book...built #1 and #2.........but I can't afford to run them.
Haven't built a Babington Burner yet...but it seems like the way to go.
Still using charcoal and on non-pension weeks.......BBQ heat beads
Speaking of charcoal,seen the Indian country people making char out of farm veg waste, recently seen a lifestyle/cooking show (food )on tv Chinese country kitchen using what looked like charcoal discs .They were round(80-100mm) and had evenly spaced holes( 4-6) Perhaps they been pressed ,probably manufactured from some farm waste.Has anyone know of these?
Here is a link to the indian char>http://www.arti-india.org/content/view/44/42/
````````````and some chinese charcoal briquette>http://www.agitc.cn/Charcoal-Powder-of-Briquetting-Plant2.htm

watson
12th Apr 2007, 11:46 PM
Thanks for the links Forge.....
Makes it easier.....especially during fire restriction season

silentC
13th Apr 2007, 09:43 AM
I saw a design for a waste oil burner that uses a copper or brass sphere (size of a golf ball I think- it was an off the shelf item but I can't remember what it was used for). The oil drips down onto it from above. It has a hole going through the middle through which you blast air. The oil runs down over the sphere and what isn't vaporised by the air stream drips into a container to be re-used.

Not sure what the idea of the sphere was, something to do with thinning the stream out I suppose.

Propane is definately out for me. Too expensive around here. A 45kg bottle is $90 delivered here.

I like the charcoal idea because it will cost me nothing but time. Unfortunately I don't have a lot of that, either. But I have some spare time and no spare money. There's no way I would get support from the ministry of finance if these projects cost anything to run. The conversation would be like this:

Me: I want some money to buy a bottle of gas to run my burner.
She: That's nice. What's it for?
Me: So I can melt metal to make stuff.
She: Is it stuff we can eat? Can the kids wear it to school? Will the RTA take it in lieu of payment for rego?
Me: Umm, nope.
She: Ta ta...

:( :wink:

silentC
13th Apr 2007, 02:46 PM
Here is the burner design I was thinking of. Looks like it's a Babington Burner after all...

http://www.green-trust.org/2000/biofuel/babington/default.htm

Now this idea I like. There's plenty of restaurants around here :)

What really pings me off is that about 4 years ago we chucked out a perfectly good fuel oil burner that used to heat the hot water at the old place. We ummed and ahhed about it for awhile but we were in clean-up mode, so out it went. I imagine it would have been perfect for this application...

watson
13th Apr 2007, 03:35 PM
G'day again Silent,
Yep, that's a definite Babington...some models I've seen have used very unusual spheres, such as ping-pong balls/golf balls and brass door knobs.
I didn't beleive them at first..but there's apparently no heat in that area.

Here's some more info......you've already got the fourth link I had

www.aipengineering.com/babington/Babington_Oil_Burner_HOWTO.html
www.babingtontechnology.com/how_does_the_babington_burner_work.htm
http://dragoneagle.50megs.com/metalworking/babington.html

journeyman Mick
13th Apr 2007, 05:21 PM
..............Propane is definately out for me. Too expensive around here. A 45kg bottle is $90 delivered here...............


Over $100 per 45kg bottle pick up here.:( (The tyranny of distance)

Mick

silentC
13th Apr 2007, 05:27 PM
Wont be long before we get there too mate. It was $88 last year, $80 the year before that. Plus they charge a rental on the cylinders but that doesn't increase with usage. Of course it goes up every year too.

We only had a gas heater last year, so it was an expensive winter. In the throes of installing a wood fire now...

DJ’s Timber
13th Apr 2007, 06:19 PM
I just had one delivered today, cost $85.50. Bugga's are starting to get higher in price. I only use it for my cooking and go thru 1 a year

yaryetnom
13th Apr 2007, 07:57 PM
I have used 3 types of fuel. Heat beads, coke & charcoal from the remains of where farmers had burnt of piles of trees. The charcoal burnt hot enough to do small forgings but didn't last long & spat out heaps of sparks. The heat beads were used for forging a 300 mm ring out of 25mm x 150mm stock approx. This also worked well but I wouldn't have liked to try welding with it. I now use nut coke I purchased from the coke works in Bowen a few years ago & this is good to use.

Ray

forge
13th Apr 2007, 11:54 PM
G'day All,
Propane in this present day costs a heap.....it's up to you guys but a google on Babington Burners could give you a new perspective on waste oil burners.
Sump oil......fine orifice........air pressure.....melt metal.
Waste oil burners:here are some links:
url.http://www.abymc.com/
< >http://stephenchastain.com/books5.htm
regards

IanW
17th Apr 2007, 10:31 PM
Hey Silent - I just saw this thread so thought I'd put in a belated two bob's worth.
Charcoal is nothing more than more-or-less pure carbon that just didn't burn to CO2 for reasons I can't explain from 1st year chemistry. Anyway, you can often pick up bags of it after a bushfire (the old man used to send us kids out with a chaff bag after fires, to feed the farm forge). I can gaurantee you are able to melt steel with decent hardwood charcoal - we done it lotsa times - teenage boys, scrap metals, forge - fun! (But what the point of it all was escapes me now!! :B )

But best of all was good black coal, picked up from the railway line, back when the local puffer ran on the stuff - once you got that stuff going, you were really cooking!

Cheers
(from a very crude old bush blacksmith...)

silentC
17th Apr 2007, 10:36 PM
It's been a long time since there was a train, let alone one that burns coal, anywhere near here!

There's been a heap of burning off lately, so I'm going to go around and collect some of the leavings and see how it goes. All I need now is some refractory clay to make a furnace. And some time to build it...

johnc
17th Apr 2007, 11:35 PM
The old way to produce charcol was to dig a pit, put in heaps of green Euc and set it alight. Once it was burning well you place sheets of iron over the hole, covered in earth and left it pretty much air tight and left it for some time. If you got the process right you would be left with real charcol, if it was still smoldering when the iron came off you stood a good chance of being burnt to death when the oxygen hit it. Another place to get it from was the old gas factories that disappeared when natural gas arrived, the coke from those was very good for the forge. Hope this useless bit of info is of interest to someone. The rubbish left in the fire is pretty ordinary and needs plenty of incentive to create good heat.

John

19brendan81
23rd Jun 2009, 11:20 AM
Charcoal is wood that has been heated to a very high temperature in the absence of oxygen. Hence why it forms at the base of a big fire. The heating drives off all of the moisture and sap and other bits and pieces that exist in timber, leaving behind relatively pure carbon...which is a clean and excellent fuel source for a home foundry or forge.

Briquettes are sort of man made charcoal. They are not suited to foundry work due to the copious amounts of ash they make, and the incredibly quick burn times. During my initial experiments with my foundry I gave up on these real quick.

I read much earlier in this thread that someone in sydney had access to some coke. Is that still the case? I would love to get hold of some of that stuff for my foundry, I reckon it would work exceedingly well!

Woodlee
23rd Jun 2009, 10:11 PM
I was of the belief that briquettes were made from compressed coal dust .

Then there was the woodettes made from compressed sawdust sold for home combustion heaters.

Kev.

19brendan81
24th Jun 2009, 10:39 AM
Im referring to "heat beads" and homebrand briquettes which are a wood product chiefly as they are aimed at the BBQ cooking market where coal products are a strict no no. Besides wood they have a whole heap of other stuff in them.They are designed to burn at a relatively low heat for a long time (vs plain charcoal or wood). Of course when you blast air through them this all goes out the window, and they burn up super quick with progigal amounts of ash.

Back in the day when we had an old wood fire dad used to buy a product which I think is what you are referring to. It was a coal product and was definately compressed into a regular shape. I would love to get my hands on some of that for a go at home as I reckon it would be good.

silentC
24th Jun 2009, 10:49 AM
The briquettes that Woodlee is referring to were made from crushed and pressed brown coal. They were about 6" or so long like a small brick with rounded ends. I remember our water heater used them when I was a kid. They are still available I believe and still made from low grade coal.

In the northern hemisphere, the word is probably associated more with charcoal or peat products.

19brendan81
24th Jun 2009, 10:56 AM
Looks like they are... Check this link.

www.bestburningfirefuels.com.au (http://www.bestburningfirefuels.com.au)

I notice they sell coke too, that would be awesome to get hold of! I used to work in a BBQ and Heating store in Canberra and we never sold anything like this.

silentC
24th Jun 2009, 11:03 AM
Yep the Heat-a-brix would be similar to what we used to get. They were pretty common as a fuel in Victoria in the 60's when I was a kiddy. They were made at Yallourn or Morwell, which was pretty close to where we lived. I can remember helping Dad light the heater. He used Jiffy firelighters to get it started and one or two briquettes would heat up the water for a bath.

19brendan81
24th Jun 2009, 11:09 AM
Im going to scout around canberra to see if I can round some of this up.

IanW
24th Jun 2009, 02:16 PM
Brendan - my neighbor is a farrier & buys coke for his forge in bulk. If you know any horsey people who can point you to any local farriers who still make their own shoes, you might be able to buy enough to keep a weekend warrior going for quite a while? Probably easier than charging about the bush with a sack looking for piles of charcoal, which would be my other suggestion. But not as much fun.....
:U
Cheers,

silentC
24th Jun 2009, 02:26 PM
Since starting this thread two years ago, I've discovered that a bloke I know is a farrier. He makes his own charcoal for the forge occasionally but mostly he just burns hardwood down and uses the coals.

When he makes charcoal, he does it in a drum with a fire underneath. I've been meaning to go around and have a look, he lives about 5 minutes from my place.

Grahame Collins
24th Jun 2009, 09:02 PM
Ooo Aghh,
I like this thread.
It should n't be too hard to do some aluminium founding,if thats the word,then.

I would like to make some pipe die formers and pulleys by casting and then machine on the lathe.

How many of us cast and machine aluminium?
Enquiring minds wish to know.

Grahame

echnidna
24th Jun 2009, 09:42 PM
have cast ally many years ago

My forge was a 13"' holden whhel on the ground and loose sand packed around the perimeter. I used the blower side of an old vac cleaner for the air.

Despite looking like something made by Heath Robinson it worked extremley well

19brendan81
25th Jun 2009, 10:14 AM
Ooo Aghh,
I like this thread.
It should n't be too hard to do some aluminium founding,if thats the word,then.

I would like to make some pipe die formers and pulleys by casting and then machine on the lathe.

How many of us cast and machine aluminium?
Enquiring minds wish to know.

Grahame

Melting the aluminium is childs play....anyone can do it. I did it on a campfire on the weekend. Venting the mold is the hard part. The first part I made was a cast steering boss for a go kart. It came out needing significant cleaning up, but I spose you could call it a success.

Next was a new swing arm for my mates remote control car. despite being asthetically not that flash, it functions perfectly to this day with no further machining required.

Thanks to this thread I got onto Cast Metal Services in brissie re some "petrobond". Turns out they had a 25kg bucket of it in sydney and im getting a mate to pick that up on monday. Cost was $83.97 inc GST. They make this stuff themselves, the price I listed in this thread before was for brand name Petrobond, imported from the united states. I found a guy in vic who sells this for $260 for 20 kegs.

Im hoping my results will improve significantly with this sand. Some of the stuff blokes are casting on the net has very fine detail, which is what im trying to achieve.

silentC
25th Jun 2009, 10:18 AM
Is it reusable?

19brendan81
25th Jun 2009, 10:46 AM
Yeah, for a fair while from what I understand. Especially when casting aluminium. You need to do some "mulling" between uses (mixing/fluffing of the sand), but as its oil based it doesnt dry out like green sand does which not only needs to be mulled but also needs to be brought back up to the correct moisture level.

I think the idea is that you throw away the charred bits of sand from around the pattern, and then keep the rest...depending on how many melts you do you eventually throw out all your sand.

jmk89
25th Jun 2009, 11:08 AM
BTW ISTR reading somewhere (old Model Engineer perhaps) that the best charcoal for forges and furnaces is/was made from plum stones.

Sounds like someone needs to find out what a jam-maker does with its plum stones and get a few sacks...:)

Tez2
11th Jul 2009, 06:19 PM
I had only just gotten a hold of some home foundry books from the Workshop Practice Series, as i have a bit of scrap Aluminium that i would like to turn into shapes suitable for turning and milling also.

Will be interesting to find others on the forum with likewise interests, and maybe other info on making a home melting furnace as well.

Tez2

RayG
11th Jul 2009, 10:08 PM
Hi Tez,

I have just completed a propane foundry, we did our first bronze pour last night, melted 1kg of bronze in about 7 minutes. :D exciting stuff.., just ingots at this stage. Haven't actually cast anything useful yet. I was looking forward to doing some more today, but the rain has settled in, so I'm making a better crucible pouring setup and a set of lifting tongs.

As this thread is about charcoal powered foundries, I will start a new thread in a few days time, and give a bit of a description of the propane burner and the furnace construction.

Regards
Ray

19brendan81
13th Jul 2009, 10:51 AM
RayG do you know what sort of fuel consumption you get out of your propane burner?

RayG
13th Jul 2009, 08:31 PM
RayG do you know what sort of fuel consumption you get out of your propane burner?

Hi Brendan,

Still haven't measured it. I am planning on commandeering the bathroom scales to sacrifice in the interests of the cause. So I should be able to get an idea of Kg/hr of propane at various pressure settings.

I did a bit of research and here a few numbers of interest.

1. It takes 12.3 cubic meters of air per Kg of propane for complete combustion.
2. Each Kg of propane produces 12.9 KiloWatt Hours of power.

From the amount of propane being burnt, you can calculate the total power input to the furnace, and how much air is required (if using a blower).

I suspect that I'm using 2-3 Kg/hour (don't really know yet) so probably about 25-40 KW of heating..

Regards
Ray

silentC
14th Jul 2009, 09:00 AM
I'd like to see someone have a go at making one of these:

http://www.green-trust.org/2000/biofuel/babington/default.htm

You can burn waste cooking oil.

19brendan81
14th Jul 2009, 10:45 AM
2 -3 kg per hour isnt bad. If your alloy melt only took 7 mins you would get a lot of melts out a 9kg cylinder.

I tried making a waste oil burner but didnt get it right. I gave up because of the smell it produces, it was pretty ordinary and you could smell it down the street. I wouldnt get away with it long until a neighbor complained.

i got my petrobond sand last night, its so awesome. I think ill finally be able to get the casting results I have been hoping for.

yjnb
14th Jul 2009, 12:40 PM
Ray,

Are you using a regulator for your propane burner? also is it a 1 inch or 3/4 inch burner?

Regards,

James


Hi Brendan,

Still haven't measured it. I am planning on commandeering the bathroom scales to sacrifice in the interests of the cause. So I should be able to get an idea of Kg/hr of propane at various pressure settings.

I did a bit of research and here a few numbers of interest.

1. It takes 12.3 cubic meters of air per Kg of propane for complete combustion.
2. Each Kg of propane produces 12.9 KiloWatt Hours of power.

From the amount of propane being burnt, you can calculate the total power input to the furnace, and how much air is required (if using a blower).

I suspect that I'm using 2-3 Kg/hour (don't really know yet) so probably about 25-40 KW of heating..

Regards
Ray

RayG
14th Jul 2009, 03:01 PM
Ray,

Are you using a regulator for your propane burner? also is it a 1 inch or 3/4 inch burner?

Regards,

James


Hi James,

http://www.backsaw.net/pics/burner.jpg

http://www.backsaw.net/pics/boc_reg.jpg

The burner is 1 1/4, and the regulator is a BOC 6000 LPG regulator

The sheet metal flare burnt out, and the ceramic flare cracked when dropped, before it even got into the furnace, so I've got to cast a new refractory flare sometime soon.

The bathroom scales were a dead loss for measuring the propane consumption, they are the digital type that automatically turn off, when you try and read the weight :oo:

Regards
Ray

yjnb
14th Jul 2009, 05:41 PM
Wow,

That's quite a burner. Would you mind posting where you got the plans, and how you constructed it? Perhaps this would be better put in your new thread.

I have a 3/4 inch Reil burner and a 3/4 inch Frosty T burner (you'll know it if you have been on Iforgeiron). The Frosty burner is the better of the two. Both are made from steel plumbing pipe and work OK. They don't melt 1 kg of brass in 7 minutes though, more like 15 minutes.

I have cast a couple of knobs/ screws for wooden planes and one lever for a record lever cap. It's easy to get close enough to shape and finish with filing/ sanding, but hard to get a decent finish off the bat.

Looking good, can't wait to see some casting

Regards,

James

Tez2
3rd Aug 2009, 11:10 AM
Hi Tez,

I have just completed a propane foundry, we did our first bronze pour last night, ........................ I will start a new thread in a few days time, and give a bit of a description of the propane burner and the furnace construction.

Regards
Ray


Would love to see what you have, both the foundry and how the burner goes.

I have started the casing for my foundry, using old LPG bottles. I filled them with water after venting them for some time and blowing them out fully with compressed air, emptied the water out and cut the top off with an angle grinder cut-off wheel.


******************


For safety sake, all remnants of gas must be removed from the cylinders before cutting them, the Gas/Air mixed with grinder sparks wouldnt make for a happy day at all.
NEVER :no: attempt this with any cylinder that has even a hint of gas in it...........


******************


One thing i did notice was that the insides of the bottles after cutting them up had a whole heap of rusty crud inside, and the inside walls had a rust coating on them which had to be removed with a wire brush on the angle grinder.

The top of the cylinder has now had a 100mm hole cut in it and is ready for drilling to put in small bolts and securing wire to hold the castable insulation in place.

The bottom section is being prepared at the moment to have a suitable hole drilled in the perimeter for a burner, which i have yet to make up, and will probably be on the basis of using a 200mm length of 1" od black water pipe.

For the refractory material i am considering using the mix i had come across that utilises grog and fireclay to see how that stands up.

Any suggestions would be most welcome as regards construction in any of its forms...

Tez2

RayG
3rd Aug 2009, 03:41 PM
Would love to see what you have, both the foundry and how the burner goes.
<snip>
For the refractory material i am considering using the mix i had come across that utilises grog and fireclay to see how that stands up.

Any suggestions would be most welcome as regards construction in any of its forms...

Tez2

Hi Tez2,

I would use a ceramic blanket lining on the inside of the refractory mix, the problem with (just) using a solid refractory material is that it is a poor insulator when compared to the Kaowool (or in my case Cerachem) what this means is that you will be losing a lot of heat just heating up the refractory and will require more heat input to get up to temperature.

Then, the ceramic blanket needs to be protected with a coating, I used ITC-100 which is an infra-red reflective coating that further acts to keep the heat in.

Hope this makes sense.

Regards
Ray

19brendan81
4th Aug 2009, 12:42 PM
Ray G your approach seems valid but would it not be overkill for a home foundry? I built my foundry with plain portland cement, and it melts aluminium using charcoal as fuel in 5 - 7 mins, has done 10 or 12 melts and is still going strong. The portland has no insulation in it whatsoever, no perlite etc. The outside of my foundry remains cool to touch after two or three melts in succession.

I guess what you choose to use Tez will depend on how often you plan on using your foundry. If you break it out once every couple of months like me, you can have one ready to go for about $20. If you want to use it every day you might want to consider Rays approach.

RayG
4th Aug 2009, 08:54 PM
Hi Brendan, Tez,

Yes, the extra insulation just lets you get to higher temperatures, so you are correct, it is probably overkill for Aluminium (~650 C) casting.

With the setup I have built it is my intention is to have the capability to do cast iron (~1300 C) and of course bronze (1000 C). Haven't actually tried to melt any cast Iron as yet, the silicon carbide crucibles are not rated that high, but I have a clay graphite crucible that will do the job.

Having too much fun with bronze and aluminium at the moment..:D

So, whether it's worth the extra expense is dependant on exactly what you are wanting to do.

Regards
Ray

19brendan81
5th Aug 2009, 10:16 AM
Cool. Being able to cast iron would be awesome.

Tez2
6th Aug 2009, 01:43 AM
Hi guys,

I came across a book that has heaps of info on foundries, furnaces, burners, refractories etc and the info is really great on all aspects of building the furnace as well as varying sizes of LPG burners.

208 pages

Book title is Gas Burners for Forges, Furnaces & Kilns by Michael Porter

I found a downloadable version which is about 70.4Mbin size, anyone interested in the link just send me a PM

ergowoodwork
29th Aug 2009, 09:20 AM
I´m interested guy! Could you send me it, please?


Hi guys,

I came across a book that has heaps of info on foundries, furnaces, burners, refractories etc and the info is really great on all aspects of building the furnace as well as varying sizes of LPG burners.

208 pages

Book title is Gas Burners for Forges, Furnaces & Kilns by Michael Porter

I found a downloadable version which is about 70.4Mbin size, anyone interested in the link just send me a PM

hughie
5th Sep 2009, 10:44 PM
.Heres a few links to get you going

http://www.beautifuliron.com/smithforge.htm
http://www.moosecreekforge.com/hints.html