Home Foundry

[GreenTwin]

Some of the patterns on display at the Soule Museum, Merridian Mississippi:

 

[GreenTwin]

More patterns from the Soule museum:

 

[GreenTwin]

Here is the big cupola at the Soule foundry.
The coke and scrap iron were fed into it via a doorway located at the mezzanine level.
Must have been an impressive tap when it was full.

 

[Richard Carlstedt]

Pat, I knew I had seen that Green Engine somewhere ..at NAMES of course ! and You as well !
Thank you for the very kind words
Yes, you leave the wedge and the rest of the pour overnight. The wedge break came before any machining the next day , and I have to say my first castings were very cold, until the metallurgist got involved
I would not try to do castings again without the vanadium shot
Wonderful Pics

Rich

 

[GreenTwin]

Rich-

I a still chuckling about you dropping that screw under the table, and getting your wife out of bed at 1:00 A.M. to help find it.
I would have been tempted to bean you on the side of the head if you woke me at 1:00 to look under a workbench, but that is just me of course.

If I tiny screw falls under my workbench, I immediately call it "gone for good", but your shop is a lot cleaner than mine!
If I need 10 screws or nuts, I always turn 12, because there is some law of physics that two will vanish into some mysterious black hole under the bench, never to be seen again.

The consensus at least in the backyard circles that I read these days (and have found to be true with what I do) is that you can drill and/or break one or more of the gates after the casting has cooled.
If you can easily drill a gate, which is very thin, that is really all the test you need.
And if you can break a gate and get a clean gray surface, you are good to go.

Once you get the ferrosilicon level figured out, there really does not seem to be a chill problem, but some people add things for "insurance".
I prefer to not fix things that are not broken.
Similarly, I don't degas melts that are not producing gas defects. Some folks just degas everything, regardless of the need.

I think I am in the range of 0.04-0.06 oz of ferro per pound of iron.
I use a graphite rod to stir it into the melt, while the crucible is still in the furnace, and often with the burner still running (with a very long handle on the stirring rod, and a hand sheild).
I use 75% FeSi, obtained from a foundry supply house; works very well.

Pat J

Edit: I am told that you can heat a chilled casting to a cherry red, and then let it cool overnight, and you can salvage it from hard spots (chills).
I have not tried this method because I have not had chills when using ferro with the new furnace.

I did create some partial mold filled thin parts in the early days of my casting adventure, with the first furnace, and those were as hard as tool steel ("uncutium" is what I call the alloy), and that was before I discovered ferrosilicon.
.

 

[Richard Carlstedt]

Yes on that reheating . Had a Foundry cast railroad wheels ( like 100) for a club project and they were as hard as a IRS agent and we sent them back and that is what they did , reheat to cherry and then bury them under a sand pile for a day or two and they came back redish rusty, , but nice and soft.

True story fellows and yeah ! , my wife is a "Keeper"

Not worked with Ferro at all- I used broken Flywheels from a farm tractor repair shop at the suggestion
of the metallurgist ...It is really good iron as they can;t take chances with slipshod material in a high RPM application..according to him.
"broken" means application of a sledge hammer by your truly to get my size down..by the way , he also told me not to use limestone because i was not using pig iron ( but good flywheels) - boy did that make a difference in the melt ( cleaner)

Rich

 

[GreenTwin]

I have been following Kory Anderson's work the last year or so.
Kory is one of those unique individuals who are just unstoppable when they make up their mind to build something.

If you have not heard of Kory, he decided to build the world's only 150 hp Case tractor, and so he made the patterns, cast his own parts, and created his own tractor !!!!
Phenomenal is all I can say.



But the reason I mention Kory is that he has some photos on his website (somewhere?):
https://koryanderson.com/projects
that show a flywheel with a cracked spoke (I can't find the link to the photo, but if I do, I will post it).
He cast some new flywheels in ductile iron.
That is the first cracked flywheel spoke I recall seeing on a steam engine.
I suspect that many of his 150 hp Case parts were cast in ductile iron.

My next foundry mission is to master the art of making ductile iron.
I know how to do it.
I am trying to find the correct additives that I need, and as usual, sourcing those has been extremely difficult.
Nobody wants to sell a little bit of anything.


Edit:
Found a few photos here. Not the photos I was looking for, but interesting just the same.
https://www.jamesvalleythreshers.com/project/150-hp-case-project-kory-anderson/
Edit2:
Quite a few build photos here, but still not the flywheel I was looking for.
https://150case.com/about-the-engine/

 

[dazz]

Dazz- Yours is a big order and I admire you for the undertaking of it.

I just need to make a hole in the sand and fill it with iron. How hard could that be??
I am reasonably confident that the path to success will be paved with failures.

Are you going to pour it yourself or have a Commercial or Art Foundry do it for you ?

This is DIY. Getting a commercial foundry to do the job here would cost $$$$$$$$$$$$$$$

My first comment is you should probably look at Silicon iron and definitely use a Vanadium additive. This will improve fluidity and machining immensely ( Vanadium) . Years ago this additive which is put in just before the pour was called "Hot Shot" as it creates a exothermic reaction ( sparks) and raises the temp of the pour which adds to being able to pour thin walls.

The plan is to use cast iron engine blocks. These will already have the right metallurgy for my application.

Good luck
Rich

I will need more than luck !!

 

[dazz]

A few years ago, I found out that SS can be set using a catalyst, and so I actually purchased some catalyst, but have not tried it yet.

After a bit of research, I found that SS can be set with an acid. Any acid would work but you would not want to use something like HCl that would release Chlorine into the metal.

The thing to remember is that the bound sand only has to last long enough for the exterior of the metal to solidify.
Resin burns too, and it creates a charred interior of the mold, which I think actually helps with surface finish.
Since the binder is a small percentage of the sand, then the main point of contact between the molten iron and the mold is the face of the grains of sand, not the binder.

I have found references to using ships bottom coal as an additive to improve surface finish. This is very fine coal that get ground down as a result of the ship's motion. On contact with hot metal it will burn all the oxygen then just form a carbon layer. Fe2O3 (rust) has also been used but modern ceramic powders seem to be the modern approach.

If a mold is made of some material that is too hard, supposedly it can cause a casting failure; not sure of the exact mechanics of that.

Google hot tears and rat tails.

 

[GreenTwin]

Until I saw John's jumbo coin castings at the Soule museum, I had no idea that they were manufactured and available.

I was able to find a selection of jumbo coins online for sale, and so I purchased some of them.
I am not sure who makes these, but the are exactly accurate.

John sometimes mixes and matches his coins, with two different styles back-to-back.

I tried casting on jumbo coin using petrobond, but did not have much success with it.
At the time I did not know much about casting work, so I need to revisit the jumbo coin casting thing.

These castings make a great demonstration and give-away at shows, and it does not take much of a furnace or burner to cast them.
John uses a propane torch to melt the aluminum, and I think a steel crucible.

Steel crucibles are prone to degradation and failure, and so I would recommend using a small clay-graphite crucible, or even a small jewelry ceramic crucible.
The Morgan Salamander-Super clay graphite crucibles work very well with iron (they are ferrous-metal rated, unlike most other crucibles, and rated for 2,900 F), and they come in very small sizes such as a #0.5, which is quite small.

The 0.5 Salamander Super is 3" tall.

 

[GreenTwin]

This is my optical pyrometer.
I have not tried to use it with my new furnace, but I need to get it back out and try it again.
I was not able to get a good reading with it when I tried it with my 1st furnace, but I want to try again.

I converted it to use standard alkaline batteries.

The emersion pyrometers for iron are extraordinarily expensive, and the expensive iron-rated tips do not last long either.
Iron temperatures will immediately destroy an immersion pyrometer thermocouple/tip that is used for aluminum.

Hopefully I can get this unit working.
I can pour iron without it, but it would be nice to be able to verify what sort of iron pour temperature and superheat that can be achieved.

 

[Richard Hed]

I have been following Kory Anderson's work the last year or so.
Kory is one of those unique individuals who are just unstoppable when they make up their mind to build something.

If you have not heard of Kory, he decided to build the world's only 150 hp Case tractor, and so he made the patterns, cast his own parts, and created his own tractor !!!!
Phenomenal is all I can say.



But the reason I mention Kory is that he has some photos on his website (somewhere?):
https://koryanderson.com/projects
that show a flywheel with a cracked spoke (I can't find the link to the photo, but if I do, I will post it).
He cast some new flywheels in ductile iron.
That is the first cracked flywheel spoke I recall seeing on a steam engine.
I suspect that many of his 150 hp Case parts were cast in ductile iron.

My next foundry mission is to master the art of making ductile iron.
I know how to do it.
I am trying to find the correct additives that I need, and as usual, sourcing those has been extremely difficult.
Nobody wants to sell a little bit of anything.


Edit:
Found a few photos here. Not the photos I was looking for, but interesting just the same.
https://www.jamesvalleythreshers.com/project/150-hp-case-project-kory-anderson/
Edit2:
Quite a few build photos here, but still not the flywheel I was looking for.
https://150case.com/about-the-engine/

That is really something. Wish I had it in my yard.

 

[Richard Hed]

Until I saw John's jumbo coin castings at the Soule museum, I had no idea that they were manufactured and available.

I was able to find a selection of jumbo coins online for sale, and so I purchased some of them.
I am not sure who makes these, but the are exactly accurate.

John sometimes mixes and matches his coins, with two different styles back-to-back.

I tried casting on jumbo coin using petrobond, but did not have much success with it.
At the time I did not know much about casting work, so I need to revisit the jumbo coin casting thing.

These castings make a great demonstration and give-away at shows, and it does not take much of a furnace or burner to cast them.
John uses a propane torch to melt the aluminum, and I think a steel crucible.

Steel crucibles are prone to degradation and failure, and so I would recommend using a small clay-graphite crucible, or even a small jewelry ceramic crucible.
The Morgan Salamander-Super clay graphite crucibles work very well with iron (they are ferrous-metal rated, unlike most other crucibles, and rated for 2,900 F), and they come in very small sizes such as a #0.5, which is quite small.

The 0.5 Salamander Super is 3" tall.

View attachment 128006


View attachment 128007

Damn! That guy REALLY has small hands!

 

[GreenTwin]

Continuing the discussion of sodium silicate bound sand............

I have used sodium silicate bound sand with aluminum, but not with iron.
I have had discussions with the local art-iron group, and they have used SS sand with iron, and report good results.

One thing I do with resin-bound molds is to flame them lightly with a wide propane flame, to drive off any residual resin or moisture.
A second thing I do with resin-bound molds is to spray them with a ceramic mold coat, which helps greatly with creating a smooth surface finish.

I have not tried spraying ceramic mold coat (alcohol-based) onto a SS mold, and don't know if it would dissolve the SS or not.

The resin molds have to be flamed first, the ceramic mold coat sprayed on, and the molds flamed again.

If I had a bit more time, I would go out to the shop and experiment with some SS molds, and mold coat.

I think one can get results similar to resin-bound sand, using sodium silicate bound molds; that is what I have heard.

And sodium silicate is readily available at pottery supply houses too, unlike resin for molds.

Sodium silicate molds can be cured with CO2, or a catalyst can be added that automatically cures SS molds.

It is important to keep the patterns well waxed with bound sand, since they tend to cling to the sand.
And if you leave your pattern in bound sand after the strip time, then your pattern is basically permanently glued into the mold (don't ask me how I discovered this).

I found some sodium silicate catalyst at Clay Planet.
The catalyst is at the bottom of the page.
Unfortunately it is slow acting, and I can't find the faster acting catalyst.
The slow catalyst may work if you are patient.

https://shop.clay-planet.com/chembond-4905-no-bake-binder---5-gallon-bucket.aspx
The 3-part resin-binder system I use has a resin, a hardener, and a catalyst, and so I can dial in the set time to as short as 5 minutes.
You have to allow enough time to mix for about 2 minutes, and also time to ram the mold, so you don't want the sand to set too quickly.
The binder sets more quickly on a hot day, and I have had the sand set in the mixer (no fun cleaning that out).

.

 

[GreenTwin]

Common mistakes I see with people using sodium silicate binder:

1. They use too much sodium silicate, and like me, assume more is better (false).

2. They over-gas their sodium silicate sand. Any more than a 5 second gas with CO2 ruins sodium silicate mold strength (less is more).

3. Using the recommended percentage (I think it is 5%, but check me on that) allows a sodium silicate core to be broken down and removed from a casting.
High concentrations of sodium silicate make a rock-hard core which can be very difficult to remove.

.

 

[moose4621]

Common mistakes I see with people using sodium silicate binder:

1. They use too much sodium silicate, and like me, assume more is better (false).

2. They over-gas their sodium silicate sand. Any more than a 5 second gas with CO2 ruins sodium silicate mold strength (less is more).

3. Using the recommended percentage (I think it is 5%, but check me on that) allows a sodium silicate core to be broken down and removed from a casting.
High concentrations of sodium silicate make a rock-hard core which can be very difficult to remove.

.

When using your resin bonded sand, do you use a release agent on the pattern to prevent it sticking?
I have a fair amount of epoxy resin left over from another project and so thought I might try it for bonding sand.

 

[GreenTwin]

I wax the pattern well.

I have heard of people using epoxy resin for making sand molds, but I don't recall exactly the outcome.

Sodium silicate-bound sand is commonly used, hardened with CO2.

It does not take much resin to bond sand.
Lino-Cure (tm) resin binder is a 3-part oil-modified alkyd resin, with resin, co-reactant, and catalyst.

Resin is used at 1.5% of the sand weight.
Co-reactant is 20% of the weight of the resin.
A slight amount of catalyst is used to control the set speed.

Bound sand has a set time (when it gets hard enough to become rigid), and a strip time (you need to remove the pattern from the mold during the strip time, else the pattern will be permanently adhered to the sand.

Most epoxy seems to be a 50/50% mix, ie: resin and hardener.
So a guess would be to add 0.75% of the sand weight in resin, mix that with the sand for at least two minutes, then add 0.75% of the hardener and mix for 2 minutes.

If the epoxy is a slow setting variety, then you could have a long wait before the sand mold sets (gets rigid).
Be sure to keep the mold on a flat surface after the set time has been reached, since the sand can warp a bit right after the set time if you put it on an uneven surface. A fully hardened sand mold will not warp.
Select some time after set time, and then pull the pattern.
I use an automotive slide hammer to give a quick (light) impact force on the pattern, to break it lose from the mold.

And the sand that is used with resin binder has to be very dry, such as less than 0.25%.

The beauty of sodium silicate molds is that they set right after you gas them with CO2.
Never gas a sodium silicate mold for more than 5 seconds, else you will ruin it.

I have never used epoxy as a binder, so the above is my best guess at how to use it.

.

 

[moose4621]

Great info, thanks.
The resin I have is a 4:1 resin / hardener ratio and is a laminating resin so is quite thin. You get about a 20min pot life and about an hour to harden. It takes 24hrs to reach max strength.
I have used it before to make a few cores which went ok apart from the stench of the burning resin.
I thought it might work ok for the main sand moulds.

 

[GreenTwin]

So at that ratio, you may be closer to 1.5% of the weight of the sand for resin, such as used with Lino-Cure.

But again, mix the resin with the sand first, then add the hardener.

It should work; you may have to play a bit with the ratios.

I would not inhale the fumes after the pour.

Use plenty of wax on the pattern.

Perhaps pull the pattern a little after an hour.
And don't use an expensive pattern on your first try, in case the pattern sticks to the sand.

.

 

[Rains]

Great and creative work