Furnace Build(likely to be very slow)

[Stustoys]

With apologies to Matt for not being able to cut the keg he so kindly gave me(over a year ago now) in half just yet.

I've got myself a hot water tank thats about 900mm high and 400mm diameter. Now(I think) its a little on the high side but the diameter should be fine if my dimensions of crucibles are correct.(something else to buy)
So my first question is how thick does the lid need to be and how big a hole for the exhaust? The dome is about 80mm high and its about 80mm from there to the bottom of the outlet fitting. 80mm of straight would give me enough for 4 layers of blanket, but would an air gap above that be an issue?

I have some fire bricks that I might use in the bottom as I may end up playing with oil burners.
The Isowool I have I'm not so sure about, its 14-10SP from Isolite Ceramic Fibers SDN. BHN. I thought it was good for 1600C but now I'm not so sure and cant find out any info. Anyone happen to know anything or of a way to test it?
Mine isowool didnt come in rolls, its a 300mm square block 150mm thick, the blanket is about 20mm thick conertinaed, I'm guessing there is about 2400mm in block and I have 4 blocks.

So many little things to chase up.
Some titanium wire, I figure 20g will do?
I also need sealer? rigidiezer?

Off to reread some threads that have been waiting in my favorites list. Get ready Bob and Ray ;)

Stuart

[DSEL74]

You should ask Josh & Ray a few questions. I remember Josh saying they spent a heap of money buying the fire bricks or heat matting or something only to find another much-much cheaper way of going about it. Or I could be completely wrong I was quite overwhelmed with all their equipment as it was my first visit.

[Ueee]

The link Sawdust posted in fxst's thread has some good info. Foundry Tutorial Book (http://www.alloyavenue.com/vb/showthread.php?2469-Foundry-Tutorial-Book)
I was going to use the stuff Sawdust did, from this place. Castables, High Temperature Concrete (http://www.firebrick.com.au/high_temperature/high_temperature_concretes)
Keep on the lookout for a burner like mine, looks like it will work a treat. Spraybooths use them, as well as big hot water boilers etc.

[Stustoys]

Hi,
I believe Josh and Ray used Pyrocrete 165 but said they think blanket would be better.

Hi Ewan,
Yeah working on that link thanks.
I dont recall having seen Sawdusts furnace.
The reason I am using blanket is I am told "for guys like us" as it doesnt have the thermal mass to heat up so is better suited for us "one pour" wonders...........
I dont like my chances of stubbing my foot on a burner like yours but I will keep an eye out.
I'm just going to use bottle gas to start with as I have a 40kg bottle for the shed heater anyway. I'll have a chat to a plumber I know about whats involved in on mains gas.. though its a little early for that lol. would be nice to have a kero burner at least I go tend to use a bit of that.. I'd use more if it could be "reused"

What am I going to be paying for crucibles in oz? The only place I have found online so far in in WA.(why is all the good stuff in WA? hehehe)


Stuart

[Ueee]

salamander crucible | eBay (http://www.ebay.com.au/sch/i.html?_sacat=0&_nkw=salamander+crucible&LH_PrefLoc=2)
Yeah, those damn WA blokes hogging all the good stuff.......:D

I thought a thinish hard face and then blanket would be better.....

[BobL]

With apologies to Matt for not being able to cut the keg he so kindly gave me(over a year ago now) in half just yet.

I've got myself a hot water tank thats about 900mm high and 400mm diameter. Now(I think) its a little on the high side but the diameter should be fine if my dimensions of crucibles are correct.(something else to buy)
So my first question is how thick does the lid need to be and how big a hole for the exhaust? The dome is about 80mm high and its about 80mm from there to the bottom of the outlet fitting. 80mm of straight would give me enough for 4 layers of blanket, but would an air gap above that be an issue?

I have some fire bricks that I might use in the bottom as I may end up playing with oil burners.
The Isowool I have I'm not so sure about, its 14-10SP from Isolite Ceramic Fibers SDN. BHN. I thought it was good for 1600C but now I'm not so sure and cant find out any info. Anyone happen to know anything or of a way to test it?
Mine isowool didnt come in rolls, its a 300mm square block 150mm thick, the blanket is about 20mm thick conertinaed, I'm guessing there is about 2400mm in block and I have 4 blocks.


Is it listed on this brochure
http://www.owencorp.com/Isowool.pdf

[Ueee]

What do you want to melt Stu?
The Isowool only looks to be rated to 1500, a bit low for CI. If your burning oil i think you will want a sacrificial brick to take the brunt of the flame as it hits the side of the furnace. Or so i have read......

[Stustoys]

Hi Bob,
Thanks but I can't see any numbers that match :(
Not sure I like the "14" in my numbers though.

Hi Ewan,
I'm after CI..........nothing like jumping in at the deep end.
I was planning on putting fire brick at the bottom for that reason.
As above with the "14"
Might have to run a piece up to Ray and Joshs and see what damage they can do to it.

Stuart

[simonl]

Might have to run a piece up to Ray and Joshs and see what damage they can do to it.

Stuart

:2tsup:

[Toggy]

Stuart

A few years ago I bought a cruvible and hi temp castables from a place in Geddes? Street, Mulgrave. Their name possibly started with R

IIRC they had blanket and firebrick. How many firebricks do you want. Trouble is the the trip would be worth more than buying new firebrick.

Ken

[BobL]

The Isowool I have I'm not so sure about, its 14-10SP from Isolite Ceramic Fibers SDN. BHN. I thought it was good for 1600C but now I'm not so sure and cant find out any info. Anyone happen to know anything or of a way to test it?
Mine isowool didnt come in rolls, its a 300mm square block 150mm thick, the blanket is about 20mm thick conertinaed, I'm guessing there is about 2400mm in block and I have 4 blocks.


If it's isolite in block form then it's either Uniblok or Saber Bloc.
See ISOWOOL Uniblok and Saber Bloc - イソライト工æ¥#æ#ªå¼�会社 ｜ ISOLITE INSULATING PRODUCTS CO.,LTD. (http://www.isolite.co.jp/en/products/ceramicfiber/seihin2-3/index.html)

I'd say the 14 refers to 1400 ºC.
But all the Isolites don't melt until they get to ~1750ºC
My understanding is a 1400ºC classification a service temperature, ie will withstand multiple heatings to that temp.
Depending on how much CI you want to cast I would think the 14 should survive a couple of CI castings.

[SawDustSniffer]

my furnace has 18mm hard hot face , with 50mm of kiowool behind it

[Stustoys]

Hi Ken,
That would be Refractory & Ceramic.
Refractory & Ceramic - Crucibles, Furnaces and Master Alloys (http://refractoryandceramic.com.au/crucibles-furnaces-and-master-alloys.html)
I'd found them, wasnt sure if they would want to talk to me. Looks like I'd want just about the smallest crucible they sell(they they say they are only good to 1400C.......

I have "some" firebricks(heavy like a solid house brick not the light sandy white ones). I have no idea how many I need as I hadnt planned on using them(other than maybe a couple of rows in the bottom). I'll check

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?

Stuart

[Stustoys]

my furnace has 18mm hard hot face , with 50mm of kiowool behind it

18mm, I wouldnt have thought it could be used so thin(based on nothing at all lol). One of the things that had worried me about the "hi temp cement" route was the weight........ I would like to be able to move the thing. 18mm wouldnt be a show stopper as long as it stays together.
Any pictures on the forum?

Stuart

[Brobdingnagian]

OoooHHH! I had missed the start of this thread. Bring on the liquid metal Stu.

You were right we used pyrocrete as the outer shell for the pressure tank, We then lined the inside with 2 layers of CeraChem (just like any other thermal ceramic stuff just rated just a little higher). We melted it when we first changed over to a forced air LPG burner (later we figured it was the heat of the furnace but the flame temp that made a hot spot and with a high volume of air washed it out. When we rebuilt it we added some thin high density firebrick (from Refractory & Ceramic) at the contact point for the flame so as to not wash out the cerachem when we crank up the burner to 20m/s air. Another place to pick up crucibles is Foseco in dandenong they stock a reasonable range of silicon carbide and clay graphite crucibles not that you could tell from their website.

Foseco


19-21 Nicole Way


Dandenong

[BobL]

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/files/msds/north_america/205.pdf

[DSEL74]

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.

[Toggy]

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.:D

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

Ken

[Stustoys]

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

[RayG]

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

[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 (http://www.ebay.com.au/itm/Titanium-Color-Wire-Beadsmith-20-gauge-6yd-41809-Round-/300916417964?pt=LH_DefaultDomain_0&hash=item46100425ac#ht_1679wt_1161)


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

There just arent enough fancy dress parties these days ;)

Stuart

[Ueee]

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

[Stustoys]

Hi Ewan,


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

[Brobdingnagian]

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 (http://www.ebay.com.au/itm/Titanium-Color-Wire-Beadsmith-20-gauge-6yd-41809-Round-/300916417964?pt=LH_DefaultDomain_0&hash=item46100425ac#ht_1679wt_1161)


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

[Stustoys]

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

Stuart

[Brobdingnagian]

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

Stuart


5.5Kg

[DSEL74]

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

Metals - Melting Temperatures (http://www.engineeringtoolbox.com/melting-temperature-metals-d_860.html)
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??

[Brobdingnagian]

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)

[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

[Brobdingnagian]

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.

[RayG]

Hi Stuart,


CMA Eco Cycle
5-10 Reo Cresent
Campbellfield Vic 3061
Phone 03 9308 9415

They sell ingots of various metals with a guaranteed alloy composition.
Aluminium ingots $3.50 per Kg
Silicon Bronze $8.50 per Kg

Those prices are a few years old now... when you go there, tell the guy out the back what you want it for, and he'll recommend a suitable alloy.

When it comes to selecting aluminium recycling, the rule of thumb, is to choose things that are already cast, that's a fair bet that they will be suitable for melting down and re-casting..


Regards
Ray

[Stustoys]

Hi Ray and Josh,
At $3.50 per kg I dont think I will be chasing scrap. Not unless it lands on my doorstep.

Stuart

p.s. Thanks for the address

[eskimo]

When it comes to selecting aluminium recycling, the rule of thumb, is to choose things that are already cast, that's a fair bet that they will be suitable for melting down and re-casting..



is extruded stuff any good..I have a couple lengths of alloy extrusion that was used for the chain/guide track on garage roller door.....should I just take it to scarp merchants or is it suitable to melt and cast stuff with?

[Stustoys]

is extruded stuff any good..I have a couple lengths of alloy extrusion that was used for the chain/guide track on garage roller door.....should I just take it to scarp merchants or is it suitable to melt and cast stuff with?
If you only have a little scrap I would say it isn't worth it. With a large supply it might be worth playing with to find out how good it is, but if you are only going to say $10 I'd say scrap it and buy known ingot. Given the time, effort and cost of finding out you have wasted your time, effort and cash. Also as a beginner I like to have as many things going for me as I can.
But then again..........I havent even had a burner fired up as yet.
Stuart

[DSEL74]

I just came across this link in my search for Shrinkage and Machining tolerances…..Need to know how much oversize to make a pattern for Phosphor Bronze????

Foundry Manual (http://www.hnsa.org/doc/foundry/index.htm)
Foundry Mamual for the US Navy.



On a side not what is wrong with the forum today??????

[Stustoys]

Thanks for the link.

On a side not what is wrong with the forum today??????
Nothing I am aware of...... am I missing something? lol

Stuart

[DSEL74]

Thanks for the link.

Nothing I am aware of...... am I missing something? lol

Stuart


Was timing out loading, or not loading fully for me. Other websites were fine. Maybe I just got on her wrong side yesterday lol.

[DJ’s Timber]

Was timing out loading, or not loading fully for me. Other websites were fine. Maybe I just got on her wrong side yesterday lol.

It wasn't just you, a few of us experienced it yesterday.

What computer type and browser were you on?

[DSEL74]

It wasn't just you, a few of us experienced it yesterday.

What computer type and browser were you on?


I'm on a Mac using Safari.

[DJ’s Timber]

I'm on a Mac using Safari.

Cheers for that, same as everyone else, Mac/iPad/iPhone and Safari is the common theme.

[eskimo]

If you only have a little scrap I would say it isn't worth it. With a large supply it might be worth playing with to find out how good it is, but if you are only going to say $10 I'd say scrap it and buy known ingot. Given the time, effort and cost of finding out you have wasted your time, effort and cash. Also as a beginner I like to have as many things going for me as I can.
But then again..........I havent even had a burner fired up as yet.
Stuart

thanks Stuart
I'll keep all my old cast pulleys and toss the other

[Stustoys]

Well its turns out Foseco isnt open Saturday mornings........ lazy sods ;)
Might try again tomorrow or R and C.

I've had another one of my ideas. Would it be a stupid idea to test cast iron patterns etc with alum pours first?

Stuart

[RayG]

Well its turns out Foseco isnt open Saturday mornings........ lazy sods ;)
Might try again tomorrow or R and C.

I've had another one of my ideas. Would it be a stupid idea to test cast iron patterns etc with alum pours first?

Stuart


Hi Stuart,

Aluminium will flow differently to cast iron, so probably not worth the trouble, unless you actually wanted the aluminium parts...

Regards
Ray

[Stustoys]

Hi Ray,
Well fine! there goes yet another cunning plan. The first thing I want to make is a new clamp block for the tailstock on my lathe. Maybe one in Aluminium for practice would be a good idea? but that would mean another crucible. Still that wouldnt be the end of the earth, I'll need one sooner or later anyway.

Just back from R & C, what a helpful bunch of guys*. Went in and had a chat about what I needed and walked out with an A8 crucible and plenty of advice for a whopping $3.84 more than I could have had it delivered for from ebay(and thats if you count GST!, and I dont have to worry about it arriving in more than one piece) :2tsup:
Ebay says its good for 12.5kgs of brass(I thought the guy said more like 15kgs?) either way I'd say thats more than enough to be picking up when white hot.
So thats one more thing ticked off the list.

Now to make some tongs so I can work out the diameter I need the furance to be.

Stuart

*I assume the girl was just as helpful, though she was having lunch so I didnt talk to her lol