Thread: Furnace Build(likely to be very slow)

Originally Posted by Stustoys

Hi Bob,
Its not a block, its a blanket.... but its folded not rolled. make sense? I think not. I'll take a picture. Takes up less space I guess.
Can you tell me more about the rigidizer you used in your furnace? If I stay with the blanket I assume I'll need to use that also?

Ah ha, that folded blanket stuff is commonly used here in WA for pizza ovens. I see packs of it for sale occasionally on gumtree by folks who want to sell their excess after making their ovens.

If any of the blanket is exposed it will slowly fray and fibres will get into the exhaust fumes and go all over the place.
My understanding is the rigidizer doesn't completely cure this problem but greatly reduces it.
Are you doing this inside a shed? If so, good ventilation is needed, not just for the remaining fibres but also exhaust gases.

The rigidizer came in 1L containers and I managed to do my small forge with ~300 mL.
I bought 2L and it cost $65 but it should do me for many relinings of the furnace.
Most rigidizers are a suspension of colloidal silica and caustic plus a few other bits and pieces.
I think the higher temp versions also contain zirconia.
Here's a typical MSDS
http://www.morganthermalceramics.com...merica/205.pdf

Originally Posted by Toggy

Trouble is the the trip would be worth more than buying new firebrick.

Stu, where are you located? Mulgrave is about 40min for me and Dandy about an hour. I could maybe go investigate for you if you need.

Stuart,

Those heavy firebicks are heat retainers and used as face bricks for fireplace and pizza/bread ovens. They soak the heat then slowly emit it. The lightweights are reflective and used in kilns/furnaces.
I have the lightweights; not sure if they are 1300c or 1700c.

R & F had carbide and graphite crucibles. IIRC the graphite are the higher temp, but more fragile.

There were several old gentlemen and I mean that in every sense. When I explained that I intended to make a furnace they almost fell over themselves to help with any question and made numerous suggestions.
Things were quiet; so maybe I was a fresh new body to talk to.

If and when I get on track with the project I will certainly deal with them again.

Ken

Hi DSEL74,
I'm SE Melb so I am likely just a little closer than you, but thanks for the offer.

Hi Ken,
R & F? or R & C..
I was thinking heavy bricks would put up with more "issues" from flames and oil etc?

Might try and get myself down there Saturday morning. Though I have a couple of other things to pick up.

Stuart

Hey Stuart,

Only just found this thread... anything we can help with let me know..

I knew you'd find an excuse to wear that helmet...

Regards
Ray

Hi Ray,

Thanks for that. I thought I was a closer to being ready to start putting things together than I am is seems lol
Though in my defence I am skipping Alum. I've got a gas reg on the way. The plan ATM is to wait until I get a crucible so I know how big things need to be. I'm thinking something that will hold 10kgs of cast iron. To much?

One of the many things I havent got on the go is titiaium wire.
6 yards of 20G long enough and thick enough?
Titanium Color Wire Beadsmith 20 Gauge 6yd 41809 Round | eBay

Originally Posted by RayG

I knew you'd find an excuse to wear that helmet...

There just arent enough fancy dress parties these days

Stuart

Titanium wire? to tie insulation is place? or am i way off.......

Hi Ewan,

Originally Posted by Ueee

to tie insulation is place?

Yes, in the lid. I figure it it works for Ray and Josh It will do for me also.

Stuart

Originally Posted by Stustoys

Hi Ray,

Thanks for that. I thought I was a closer to being ready to start putting things together than I am is seems lol
Though in my defence I am skipping Alum. I've got a gas reg on the way. The plan ATM is to wait until I get a crucible so I know how big things need to be. I'm thinking something that will hold 10kgs of cast iron. To much?

One of the many things I havent got on the go is titiaium wire.
6 yards of 20G long enough and thick enough?
Titanium Color Wire Beadsmith 20 Gauge 6yd 41809 Round | eBay


There just arent enough fancy dress parties these days

Stuart

On the subject of size, one of the things I wish we could do is to melt a full sized Alum ingot, rather than having to cut it up first.
-Josh

Hi Josh,
Just how much does a full sized Alum ingot weigh?

Stuart

Originally Posted by Stustoys

Hi Josh,
Just how much does a full sized Alum ingot weigh?

Stuart

5.5Kg

I don't know if this will assist you in spec'ing your furnace or not.

Metals - Melting Temperatures
Melting temperature of some common metals and alloys


Melting points of some metals and alloys are indicated in the table below:

Metal	Melting Point
(oC)	(oF)
Admiralty Brass	900 - 940	1650 - 1720
Aluminum	660	1220
Aluminum Alloy	463 - 671	865 - 1240
Aluminum Bronze	600 - 655	1190 - 1215
Antimony	630	1170
Babbitt	249	480
Beryllium	1285	2345
Beryllium Copper	865 - 955	1587 - 1750
Bismuth	271.4	520.5
Brass, Red	1000	1832
Brass, Yellow	930	1710
Cadmium	321	610
Cast Iron, gray	1175 - 1290	2150 - 2360
Chromium	1860	3380
Cobalt	1495	2723
Copper	1084	1983
Cupronickel	1170 - 1240	2140 - 2260
Gold, 24K Pure	1063	1945
Hastelloy C	1320 - 1350	2410 - 2460
Inconel	1390 - 1425	2540 - 2600
Incoloy	1390 - 1425	2540 - 2600
Iridium	2450	4440
Iron, Wrought	1482 - 1593	2700 - 2900
Iron, Gray Cast	1127 - 1204	2060 - 2200
Iron, Ductile	1149	2100
Lead	327.5	621
Magnesium	650	1200
Magnesium Alloy	349 - 649	660 - 1200
Manganese	1244	2271
Manganese bronze	865 - 890	1590 - 1630
Mercury	-38.86	-37.95
Molybdenum	2620	4750
Monel	1300 - 1350	2370 - 2460
Nickel	1453	2647
Niobium (Columbium)	2470	4473
Osmium	3025	5477
Palladium	1555	2831
Phosphorus	44	111
Platinum	1770	3220
Plutonium	640	1180
Potassium	63.3	146
Red Brass	990 - 1025	1810 - 1880
Rhenium	3186	5767
Rhodium	1965	3569
Ruthenium	2482	4500
Selenium	217	423
Silicon	1411	2572
Silver, Coin	879	1615
Silver, Pure	961	1761
Silver, Sterling	893	1640
Sodium	97.83	208
Steel, Carbon	1425 - 1540	2600 - 2800
Steel, Stainless	1510	2750
Tantalum	2980	5400
Thorium	1750	3180
Tin	232	449.4
Titanium	1670	3040
Tungsten	3400	6150
Uranium	1132	2070
Vanadium	1900	3450
Yellow Brass	905 - 932	1660 - 1710
Zinc	419.5	787
Zirconium	1854	3369

• T(^oC) = 5/9[T(^oF) - 32]

What are you guys paying for you ingots, Aluminium, Brass, Nickel??

Originally Posted by DSEL74

What are you guys paying for you ingots, Aluminium, Brass, Nickel??

Depends on the alloy.

But as a guide low grade Aluminium $2-3 kg(ingot), Brass/Aluminium Bronze(scrap) $5 kg, Silicon Bronze $15-$20kg(ingot)

5.5kgs, thats big enough for about 17kgs iron
If my maths is right that should be doable.

My Reg turned up today, only just fits on the bottle, misses the guard(?) my a couple of mm's. Got to be lucky sometimes.

1290C sounds much nicer, though I assume it needs to be hotting thatn that to pour?

$2-3 kg! my scrappy charges $6.6 kg for his scrap.

Stuart

Originally Posted by Stustoys

5.5kgs, thats big enough for about 17kgs iron
If my maths is right that should be doable.

My Reg turned up today, only just fits on the bottle, misses the guard(?) my a couple of mm's. Got to be lucky sometimes.

1290C sounds much nicer, though I assume it needs to be hotting thatn that to pour?

$2-3 kg! my scrappy charges $6.6 kg for his scrap.

Stuart

Specialty scrap dealer, the sell the RMI ingots I'll remember the name later, I had put a post up about them some time ago.