Casting your own steam engine castings?

[dazz]

Pulsing the fuel pressure is reported to save a significant amount of fuel oil when used to fire a furnace, but I have not tried this yet, and not sure how I would produce the pulses.
The pulsing is helping to maximize the hottest part of the droplet flame envelope.

.

We may have read the same reports. I have considered pulsing fuel supply using the conceptual device below.
The Green is a pin with a tapered end. It is sealed with an O-ring in the purple housing. As the pin rotates, it covers and uncovers a fuel supply hole in the side of the housing. The on/off ratio can be varied by adjusting the depth of the pin into the housing.
The green pin would be rotated with a geared low voltage DC motor.

 

[dazz]

Some have questioned the data above that shows that a fuel fired crucible furnace generally as a 7-19% efficiency, which is incredibly wasteful, but this is a realistic value I think.

I call an oil-fired furnace "a poor man's induction furnace".
But an oil fired furnace can produce about 400 kW (with dual burners), and it would be very difficult to draw this much energy out of a typical residential electrical service.

Electrical services often have a demand charge, and so if you fire up your 400 kW induction furnace once a year, you pay for 400 kW per month whether you use the furnace every month or not. The utility company charges you for the capacity they have to guarantee you, regardless of whether you actually use that much capacity.

400 kW at 240 volts, single phase is 1,667 amperes.
400 kw at 208 volt, 3-phase is 1,111 amperes.

Buying an induction furnace is one thing (I have seen this recently), and finding enough power to operate it is an entirely different thing.
Do the math before you buy an induction furnace.

And if the induction furnace inverter does not come with input line reactors, then you can put so many harmonics onto the power company system that you can actually damage their equipment, and they are never happy when you burn up their equipment.

.

Hi

I can't see induction being a viable option for a home foundry.

I looked really hard at an electric element furnace. The thing with electric element furnaces is that all of the heat can be contained in the furnace. If the insulation was perfect (it never is), you could use a 100W light bulb to melt iron. It might take a week or two.
The thing that killed it was the difficulty and expense of suitable elements that could survive cast iron temps.

 

[Richard Hed]

Hi

I can't see induction being a viable option for a home foundry.

I looked really hard at an electric element furnace. The thing with electric element furnaces is that all of the heat can be contained in the furnace. If the insulation was perfect (it never is), you could use a 100W light bulb to melt iron. It might take a week or two.
The thing that killed it was the difficulty and expense of suitable elements that could survive cast iron temps.

Induction? or heating elements? I thimpfks induction might be possible for home foundry if one had a heavy enough energy source. Not sure how it would work in a home situation. wojuld it work better at higher frequencies? There are induction heaters for stove tops, why would it not work for a home foundry?

 

[GreenTwin]

I have seen 240 volt induction melters about the size of a tower personal computer, and they work well for small melts, but are difficult to scale up for many reasons. One guy who used one fed so much harmonic load back into the power company meter that he burned it up.

The induction melters also require a chiller to cool the coil, and so you need two rather complex pieces of equipment.
The one I saw actually had water cooled electrical components in it (the induction unit), so you hope you don't get a leak in the plumbing inside the cabinet.

A residental electrical panel (in the US) may be rated for 200 amperes at 120/240 volts, 1-phase, but is not rated for continuous duty.
You would be lucky to be able to run a 100 ampere continuous load at 100 amps, 240 volts, 1-phase, and that would be 24 KVA.
You would probably have to use an expensive line reactor to prevent harmonic damage to the utility company equipment.

My oil burner produces about 120 KW, and I have used it with a #30 crucible, but I think it would work with perhaps up to a #70 (I have seen others do this).
By using two oil burners, you could operate a furnace with I believe up to a #200 crucible, for a burner output of 240 KW.

At 208 volts, 3-phase, 120 KW would draw perhaps 320 amperes, which is a significant load, and would required probably in excess of a 400 ampere 3-phase electric service, or more if you have other loads that must operate at the same time.

If you had access to a 480 volt, 3-phase electrical service, 120 KW would be a circuit of about 150 ampere.

In all cases, there is no guarantee that your power system is set up to carry that much continuous load; most are not set up for that.

And the higher KW induction melters get quite expensive.
Don't forget the chiller required also gets much more expensive as the KW goes up, and it needs its own electrical circuit on top of the furnace requirements.

For someone making jewelry, a tabletop induction melter makes sense.
For someone melting iron in a #10-#30 crucible, the cost of an induction melter is a very large expense, with a very large and expensive electrical service. Don't forget that an induction unit has a given life before the electronic components fail, and will need replacing, so over time, it is not a maintenance-free arrangement either.

I have heard of someone operating a larger induction melter from a diesel generator, and that is perhaps the only practical way to run an induction melter where you don't have a large 480 volt electrical service.

As I have said before, an oil burner is a "poor man's induction furnace".
With oil burners, you could make a 240 KW furnace for very little money, and operate it for the price of the fuel.

There are examples dual burner commercial furnaces that indicate that this is a readily available and viable configuration in the #200 crucible size range.
Oil fired furnaces work quite well, they are just not nearly as efficient as an induction furnace.

.

 

[Richard Hed]

I have seen 240 volt induction melters about the size of a tower personal computer, and they work well for small melts, but are difficult to scale up for many reasons. One guy who used one fed so much harmonic load back into the power company meter that he burned it up.

The induction melters also require a chiller to cool the coil, and so you need two rather complex pieces of equipment.
The one I saw actually had water cooled electrical components in it, so you hope you don't get a leak in the plumbing inside the cabinet.

A residental electrical panel (in the US) may be rated for 200 amperes at 120/240 volts, 1-phase, but is not rated for continuous duty.
You would be lucky to be able to run a 100 ampere continuous load at 100 amps, 240 volts, 1-phase, and that would be 24 KVA.
You would probably have to use an expensive line reactor to prevent harmonic damage to the utility company equipmen.

My oil burner produces about 120 KW, and I have used it with a #30 crucible, but I think it would work with perhaps up to a #70.
By using two oil burners, you could operate a furnace with I believe up to a #200 crucible, for a burner output of 240 KW.

At 208 volts, 3-phase, 120 KW would draw perhaps 320 amperes, which is a significant load, and would required probably in excess of a 400 ampere 3-phase electric service, or more if you have other loads that must operate at the same time.

If you had access to a 480 volt, 3-phase electrical service, 120 KW would be a circuit of about 150 ampere.

In all cases, there is no guarantee that your power system is set up to carry that much continuous load; most are not set up for that.

And the higher KW induction melters get quite expensive.
Don't forget the chiller required also gets much more expensive as the KW goes up, and it needs its own electrical circuit on top of the furnace requirements.

For someone making jewelry, a tabletop induction melter makes sense.
For someone melting iron in a #10-#30 crucible, an induction melter is a very large expense, with a very large and expensive electrical service.
I have heard of someone operating a larger induction melter from a diesel generator, and that is perhaps the only practical way to run an induction melter where you don't have a large 480 volt electrical service.

As I have said before, an oil burner is a "poor man's induction furnace".
With oil burners, you could make a 240 KW furnace for very little money, and operate it for the price of the fuel.
There are examples dual burner commercial furnaces that indicate that this is a readily available and viable configuration.
Oil fired furnaces work quite well, they are just not nearly as efficient as an induction furnace.

.

Thanx for that.

 

[moose4621]

I have just built my second furnace after several years of casting aluminium successfully. I now want to progress onto casting iron and built my second furnace with that in mind.
I have read this thread with great interest and picked up a few pointers along the way.
The one ingredient I see as universal amongst most home iron foundries is ferrosilicon. I have not been able to find a source for this in Australia and hope someone here has some insight as to where to procure some of this ferrosilicon-unobtainium.
Regards Chris

PS. I live in a remote rural location so it has to be a supplier who posts.

 

[Richard Hed]

I have just built my second furnace after several years of casting aluminium successfully. I now want to progress onto casting iron and built my second furnace with that in mind.
I have read this thread with great interest and picked up a few pointers along the way.
The one ingredient I see as universal amongst most home iron foundries is ferrosilicon. I have not been able to find a source for this in Australia and hope someone here has some insight as to where to procure some of this ferrosilicon-unobtainium.
Regards Chris

PS. I live in a remote rural location so it has to be a supplier who posts.

Is it possible it might go by another name like -- diffitanium, or maybe some other tradename?

How far out from "civilization" doe you live? You are lucky in that, but it does come with that cost of finding diffitanium and other materials. How about metal? Is it difficult to get? What type of fuel are you going to use for the iron? Have you lookt into possibly making the stuff ? Is there a university with a chemistry department within internet distance? What kinds of things do you cast? Got any photos?

 

[GreenTwin]

I have just built my second furnace after several years of casting aluminium successfully. I now want to progress onto casting iron and built my second furnace with that in mind.
I have read this thread with great interest and picked up a few pointers along the way.
The one ingredient I see as universal amongst most home iron foundries is ferrosilicon. I have not been able to find a source for this in Australia and hope someone here has some insight as to where to procure some of this ferrosilicon-unobtainium.
Regards Chris

PS. I live in a remote rural location so it has to be a supplier who posts.

Here is a page on how to manufacture ferrosilicon (not something I would try).
https://www.sialloy.com/blog/ferro-silicon-manufacturing-process.html
Rich C mentioned using something other than ferrosilicon for machinability, but I have never heard of the material he mentioned.
Every art-iron and backyard iron casting person I have met over the last 8 years uses 75% ferrosilicon to improve the fluidity of the melt, improve machinability, and to prevent hard spots (called chills) in the iron.

I cast a flywheel in gray iron before I knew about ferrosilicon, and it had a rim that was perhaps 3/4" thick.
I used standard carbide bits, and did not have any problems machining it (photo below).
It is an often repeated myth that all iron castings must have ferrosilicon added in order to be machinable, and in order to prevent chills/hard spots; this is not true for thicker parts that are cooled very slowly.

Where I ran into problems was with thinner iron castings.
I made a few thin castings, perhaps 1/4" thick, and could not cut them with any saw, including a Portaband with a new (and immediately ruined) blade.

It only takes a tiny amount of ferro per melt, along the order of 0.04 to 0.06 oz/lb of iron.
The ferro I use is granulated, in chips that are perhaps 1/4" in size.
I get the melt to pour temperature, which generally takes about an hour, and then mix in the ferro while the crucible is in the furnace (sometimes turning off the burner, and sometimes leaving it running).
I stir in the ferro with a dried graphite rod (from ebay), skim, pull the crucible from the furnace, and immediately pour.

You cannot wait very long after adding the ferro, since the effects of the ferro will not last long.

And another trick to prevent chills is to keep the castings in the sand mold overnight, until they are completely cool.
Pulling an iron casting quickly out of the sand does not give the graphite in the metal time to form the nodules that make iron so machinable.

So if you are casting thick pieces, and are using carbide to machine them, you probably don't need ferro.
For thin pieces, you need ferro, or something that works just like it.

What does it cost to ship say a 1 lb package to down yonder.
I buy 75 lbs of ferro at a time.

.

 

[moose4621]

Is it possible it might go by another name like -- diffitanium, or maybe some other tradename?

How far out from "civilization" doe you live? You are lucky in that, but it does come with that cost of finding diffitanium and other materials. How about metal? Is it difficult to get? What type of fuel are you going to use for the iron? Have you lookt into possibly making the stuff ? Is there a university with a chemistry department within internet distance? What kinds of things do you cast? Got any photos?

I am not in "Outback" Australia. Although it depends on your interpretation of "outback". I am 2 hours inland from Bundaberg, Queensland. Which is not very remote by Australian standards but it is a 2 day trip to the states capital and back.
Living in a rural area comes with the advantage that any scrap metal is usually BIG and HEAVY! I don't have any problem getting scrap alloy wheels for casting aluminium, and hardenable steel alloys for machining and blacksmithing usually consists of big coil or leaf springs, and large dia drive shafts, axles, and tortion springs. And discarded hydraulic rams are a good source of material too. As for iron, I hope it will fall as easily as the other materials have.
I cast many practical or replacement parts for all sorts of things. From side covers for a quad bike, blower housing for the forge blower, tool post grinder, gearbox housing for a pto drive, adjustable tablet mounts for tractors, and a Bonelle tool and cutter grinder where I substituted many cast iron parts for cast aluminium.

I am unaware of any other name the ferrosilicon may go by. It has been called that by a couple of utube posters from OZ who I may try to contact. My fear is that they just pop down to their local foundy and by at bit as required. Not going to work for me.

 

[moose4621]

What does it cost to ship say a 1 lb package to down yonder.
I buy 75 lbs of ferro at a time.

.

Lots of good info there thank you very much.

75lbs!!!! I would imagine that to be a lifetimes supply.
According to this link it is anywhere from $16 USD to $74USD for 2Kg or 4.4lb.
There is no hurry, so the cheaper rates would be adequate I am sure.

 

[Richard Hed]

Here is a page on how to manufacture ferrosilicon (not something I would try).
https://www.sialloy.com/blog/ferro-silicon-manufacturing-process.html
Rich C mentioned using something other than ferrosilicon for machinability, but I have never heard of the material he mentioned.
Every art-iron and backyard iron casting person I have met over the last 8 years uses 75% ferrosilicon to improve the fluidity of the melt, improve machinability, and to prevent hard spots (called chills) in the iron.

I cast a flywheel in gray iron before I knew about ferrosilicon, and it had a rim that was perhaps 3/4" thick.
I used standard carbide bits, and did not have any problems machining it (photo below).
It is an often repeated myth that all iron castings must have ferrosilicon added in order to be machinable, and in order to prevent chills/hard spots; this is not true for thicker parts that are cooled very slowly.

Where I ran into problems was with thinner iron castings.
I made a few thin castings, perhaps 1/4" thick, and could not cut them with any saw, including a Portaband with a new (and immediately ruined) blade.

It only takes a tiny amount of ferro per melt, along the order of 0.04 to 0.06 oz/lb of iron.
The ferro I use is granulated, in chips that are perhaps 1/4" in size.
I get the melt to pour temperature, which generally takes about an hour, and then mix in the ferro while the crucible is in the furnace (sometimes turning off the burner, and sometimes leaving it running).
I stir in the ferro with a dried graphite rod (from ebay), skim, pull the crucible from the furnace, and immediately pour.

You cannot wait very long after adding the ferro, since the effects of the ferro will not last long.

And another trick to prevent chills is to keep the castings in the sand mold overnight, until they are completely cool.
Pulling an iron casting quickly out of the sand does not give the graphite in the metal time to form the nodules that make iron so machinable.

So if you are casting thick pieces, and are using carbide to machine them, you probably don't need ferro.
For thin pieces, you need ferro, or something that works just like it.

What does it cost to ship say a 1 lb package to down yonder.
I buy 75 lbs of ferro at a time.

.

that looks an awful lot like steel.

 

[GreenTwin]

I am not in "Outback" Australia. Although it depends on your interpretation of "outback".

My interpretation of "outback" is Australia......LOL, no offense intended, its is just that it is way down there.

I could mail you some ferro, but I thinkif I were you, I would send 100model a pesonal message first.
He is a member here, and has been pouring iron for over 100 years (just kidding, he has been pouring iron for a very long time).
He goes by luckygen1001 on ytube.
https://www.youtube.com/user/luckygen1001/videosHe may actually live close to you; I seem to have a fuzzy recolletion of him living sort of south and east in Australia, if that means anything (geography was never my strongpoint).
He would have a lot of ferro.

If he does not respond to your PM, let me know, and we will make some sort of arrangement.

I typically purchase the smallest amount of material that a foundry supply house will sell me.
If you walk in and want to buy tiny quantities, they will throw you out the door, and kick you on the way out.
Ferro is relatively cheap, or it was prior to the massive inflation we are experiencing now.

.

 

[moose4621]

Hmmm, turns out I have been searching with a hyphen between ferro and silicon.
Makes all the difference if you leave out the hyphen.
There are sources on ebay available.
Thanks to those who offered assistance.
Chris

 

[Richard Hed]

I just lookt up ferrosilicon on alibaba and moslty what it displayed was ferrosilicon magnets. Is this the same material, I wonder? iF so, you could probably get some of it from used electronics junk. I see it all the time and just toss it. It is relatively easy to break into pieces.

 

[moose4621]

My interpretation of "outback" is Australia......LOL, no offense intended, its is just that it is way down there.

None taken.
I secretly enjoy being distanced from all the commotion up there.

 

[GreenTwin]

The ferro on ebay does not look like foundry grade material.
Generally I see 75% ferro in a fine granulation.

Here is a place that sells it (may not sell less than bulk though).
https://mathews.com.au/ferro-alloys/
I would still contact luckygen1001 (100model here).
He may live 4 blocks away from you.

This is the composition I typically see for foundry work.
I use the size of about 1/2"x1/4", or more like 1/4"x1/4".
https://www.millerandco.com/products/alloys-for-iron-foundries/silicon/75-ferro-silicon/.

 

[GreenTwin]

Good news and bad news to those pursuing ductile iron.
I found a nickle-mag supplier in the States.
Bad news; it is available in 551 lb steel drums, 4 drums per pallet.

Cost would probably be $1,000,000.00 (just kidding, it would probably only be $50,000.00).

Back to the drawing board.

.

 

[Richard Hed]

The ferro on ebay does not look like foundry grade material.
Generally I see 75% ferro in a fine granulation.

Here is a place that sells it (may not sell less than bulk though).
https://mathews.com.au/ferro-alloys/
I would still contact luckygen1001 (100model here).
He may live 4 blocks away from you.

This is the composition I typically see for foundry work.
I use the size of about 1/2"x1/4", or more like 1/4"x1/4".
https://www.millerandco.com/products/alloys-for-iron-foundries/silicon/75-ferro-silicon/.

Those look like the ferrosilicon toroids out of electronics when they are broken apart. Grainy and greasy looking.

 

[GreenTwin]

This is the 75% ferro composition that Miller sells.

 

[moose4621]

I would still contact luckygen1001 (100model here).
He may live 4 blocks away from you.

A couple of thousand kilometers away as it turns out, but left him a message. Thanks. I have seen most of his videos.

This seller seems to be offering casting ferrosilicon.

Thanks again.