Casting bronze in a Buddhist temple

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Toymaker

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In Thailand, many Buddhist temples still cast their own bells and statues in bronze, and the larger works require a team effort to complete the process. In photos, this is how they cast bronze at a temple in Thailand.


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Interesting how some parts of the world ignore health and safety regulations that have taken western workers many years to get enforced.
The intense white fumes suggest a high zinc content in the melt which is unusual as bells are normally a roughly 80/20 copper/tin bronze which doesn't fume so badly.
Still ....horses for courses as they say.
Dan.
 
That is very cool.

An impressive array of furnaces for sure.

I have advised a friend of mine to run three furnaces at once for high capacity, but he says he can barely run one furnace, much less three.

That is the sort of gassing/fumes I have run into when casting brass, or alloys with copper/zinc in them.
I have used a powered respirator in the past.
My understanding is that the zinc fumes may make you feel bad, but they are not necessarily very toxic (check me on that).

Generally speaking, it is best to stay upwind of any melt, with any type of metal.

They do need safety glasses as a minimum, since those molds can contain moisture sometimes, and can be prone to ejecting the molten metal like a volcano.
I would guess these folks have done this many times, and are fully aware of the need to dry out the molds.

I would love to see the actual casting after breakout.

Their pattern and shell making process would be interesting to understand too.

Thanks for sharing; very nice !

Pat J

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I was told that one casting was a bell and the other a highly respected Buddhist monk. I was also told they use a fairly typical lost wax process. The pour was completed in the evening hours and the mold was broken out the following day, by which time I had already left, so I've never seen the finished bell or statue.

Google found this web page which explains the Thai process. How we make bronze
 
I have used two furnaces at the same time but it requires two human beings who know what they are doing to pull that off. It would be easier to build many small furnaces than to build one large furnace.
 
I was told that one casting was a bell and the other a highly respected Buddhist monk. I was also told they use a fairly typical lost wax process. The pour was completed in the evening hours and the mold was broken out the following day, by which time I had already left, so I've never seen the finished bell or statue.

Google found this web page which explains the Thai process. How we make bronze

Those are most impressive scuptures.

As I mentioned, no telling how long they have been doing that process in that part of the world, but the definitely have the process and the art aspect figured out, and no doubt have been passing that knowledge along from generation to generation for a long time (that is my guess anyway).

.
 
I have used two furnaces at the same time but it requires two human beings who know what they are doing to pull that off. It would be easier to build many small furnaces than to build one large furnace.

The largest crucible I have used is a #30, and I craned it out of the furnace, and used a pouring cart to handle it.

It is difficult to stock expensive large crucibles, and difficult and more dangerous to handle a large crucible full of iron.

The crane helps keep you away from the crucible, as does the cart.

For an occasional large pour, I think it would be more economical to pour with two furnaces/crucibles than one large furnace and crucible.

And using a small every day crucible in a large furnace is going to waste a lot of fuel.

I have seem quite a few commercial double-pours, and I guess as long as you did not develop a cold joint at the center of the mold, it would and apparently does work well.

.
 
Interesting how some parts of the world ignore health and safety regulations that have taken western workers many years to get enforced.
Typical "modern country" outlook......when I go there, I tend to admire their attitude, not poo poo it.
 
If one does foundry work, one has to do a bit of research, and get some safety gear.

I have noticed that some of the Indian/Pakistan/Asian foundries have folks who pour iron while barefooted, and often with no safety gear.

While pouring iron barefooted is probably not a great idea, it does go to show that pouring iron is not really as dangerous as folks sometimes make it.

People look at my videos, and ask "Where is my fire extinguisher?".

I tell them I am not sure, but fire is not one of my major concerns, but rather avoiding contact with molten meltal, or getting molten metal spashed back on me.

I have read that zinc fumes will give you flue-like symptoms, but are not super toxic (check me on that).

The way I see it, eye protection is really #1.
With iron, the infrared radiation from the crucible and furnace will quickly sunburn your eyes, and I noticed that my eyes felt like they had sand in them after the first few iron pours when I did not wear shaded glasses. The IR without shaded glasses will eventually cause cataracts.

Safety item #2 is to not inhale toxic vapors, sand particles, or refractory particles.

As far as I am concerned, anything beyond items #1 and 2 are gravy, and are more of a comfort thing, such as leather gloves, heat shields, etc.

I did get molten steel down inside some lace-up boots one time (using a cutting torch), and one cannot unlace and get a boot off fast enough when that happens.

I guess critical safety item #3 is to not wear anything synthetic, ie: plastic/polyester/nylon, etc.
I wear all leathers, with full leather boots (no laces).

It is actually much safer in my opinion to wear no shoes when pouring metal than wearing nylon tennis shoes.

So I do sort of cringe when I see safety Items #1, 2 and 3 not followed, but beyond that folks in other countries seem to do pretty well with minimal safety gear.

This guy shows that momentary contact with molten iron is not the fatal thing many would tell you about.



I have also personally experience having to strap on so much safety gear (on a jobsite) that my vision is impaired, the equipment is heavy and awkward, my balance is affected, and I am actually in a far more dangerous situation when I have to wear fully mandated safety gear.
So the safety gear itself can become unsafe sometimes if it is applied without common sense.

Understanding the important aspects of safety, and keeping a keen eye on your surroundings (situational awareness) is more important than most safety gear. Don't neglect items #1, 2 and 3 above though; those are needed as a minimum if you do foundry work.

.
 
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Hi Greentwin,

You are right about safety standards of Indian sub continent. There are none.
Here safety gear is luxury that only a few big companies will provide.

I remember sometimes during my childhood some wandering foundrymen would come to visit our city. They would go house to house and collect old utensils of bronze, aluminium or some mystery metal (to me) that my grandmother used to call "german". They had molds for different figurines, you choose one and they use to melt metal and cast the figurine in your own yard. No safety, we children were the most fascinated and would be nearest to the fire/ molten metal.

Nikhil
 
Nikhil-

My dad worked as a maintenance man at the family lumber mill all his life, and I recall him bringing home sheets of asbestos, which we use to play with.

And we routinely took apart light switches and played with the mercury with our bare hands, and then ate lunch without washing our hands.

The days before OSHA were pretty wild, and lots of accidents on jobsites.

Nowdays, I notice the orange plastic mushroom caps on top of rebar that stick up into the air, and this is a wise application for safety.

I sometimes design outdoor substations, and so I have to walk around under them during inspection, with 23 KV or even 35 KV crackling six feet over my head on bare bus bars. A bid disconcerting, but it pays the bills.

Mike Hailwood was a 14 times winner of the incredibly dangerous Isle of Man TT races, and he died from a collision when a drunk driver hit is car.

I worry a lot more about the drivers in my city than I do about foundry dangers.
We have folks who come racing by at 120 mph, with one or two passing on either side of one's car.
I live in one of those cities where the DA does not prosecute crime, and so the criminals do anything and everything.

Pat J
 
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In school we had a whole bunch of us learning oxy-acetylene and you'd get the occasional pop followed by someone across the room doing the happy dance. The molten metal would go down your shirt, pants, and stop at some random place in your sock before burning into you. 🤣
I also heard of a toolmaker who was die casting that got a spike in his leg when the parting face failed. Hard to say sometimes but the quantity makes a difference.

This is probably full of artistic inaccuracies but interesting on its own merit. The casting process above reminded me of the ancient Greeks.
 
I have read that zinc fumes will give you flue-like symptoms, but are not super toxic (check me on that).
I have read the same thing in connection with welding (or attempting to weld) galvanized material. Some welding-related site many years ago reported the death of someone who was trying to burn all of the zinc off of a stack of galvanized metal; it was 1) a large quantity and 2) in a space without adequate ventilation. I read this a LONG time ago, and don't remember the exact details ... and thinking back on it, I have wondered if CO played a role in the death.

But in any case, the generally accepted wisdom seems to be that normally one only gets "fume fever." I seem to remember, vaguely, that drinking milk (? or something else) could help. That may be an old wives' welder's tale.
 
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