The Foundry Zone
Equipment - Supplies - Resources
We
Promote...
American
Made
Products
and
Services.
Bringing
Jobs and
Business
Back Home.
Proud to Say, Made in USA!
Safety First!
Metal
casting
can be
an
extremely
safe
thing
to do
when
done
correctly
and
with
precautionary
procedures
in
place.
In
fact,
tens
of
millions
of
metal
castings
are
safely
done
daily
from
small
dental,
jeweler,
and
hobby
casts,
to
larger
casts
like
household
items,
automotive
parts,
cast
iron
pipes, to
industrial
and
military
size
items
like
ship
propellers,
tanks
and
cannons.
What
ever
the
size,
one
thing
remains
the
same...
Safety
First!
Take most any product manual and compare it's snazzy bullet point highlighted buy me now advertisement which motivated you to buy it, then compare them. Would you have bought the product if the advertisement showed you FIRST the fine print and one to four pages dedicated to warnings, safety issues and disclaimers shown in the owners manual? Yet you now own it like many others do and use it from electrical equipment, stoves, power tools, welding equipment, lawn mower, even your barbecue grill, etc.
The Foundry Zone wants to move the so called owners manual after information out in the open more along with the bullet point highlights of metal casting. This should help make you a more aware potential metal caster and a safer one too. So pay attention and read on. These are many of the things you need to know.
 |
 |
 |
 |
 |
 |
 |
 |
The key to pouring molten metal safely is a combination of many things some of which include:
● Planning
● Knowledge
● Proper Tools & Equipment
● Implementing Pre & Post Safety Procedures
● Testing & Practice
● Applying all of these along with Common Sense.
You have to have a plan on what it is you want to do, obtain the knowledge on how to do it, obtain the proper tools and equipment to do the task, then put Safety Procedures in place and in advance of doing it. Then test and practice prior to actually working with the high temp material and improve by practice and of course tie it all together with Common Sense and Sound Safety Practices.
Accidents and injuries generally happen from lack of knowledge in the use of or being negligent in safety precautions of things they are working with. It's the reason you learn the "Rules of the Road" to drive a car and then wear a safety belt while driving your car.
Those involved in high temperature work must learn the "Rules of the Road" in that field. Even cooking on a standard household stove requires some degree of knowledge to safely work with fire, high temperatures and materials that can burn down the house or cook up a wonderful tasty meal again and again they are proud of. So make it YOUR business to learn all you can about working with high temperatures, metals, fumes, fuels, etc. to have a safe and productive experience continuously.
~~~~~~~~~~~~~~~~~~~~~~~~
Let's start with the common tools of the trade for small scale use.
● Protective Clothing and Gear.
● Infrared / Ultraviolet Hazards.
● A Safe Work Area.
● A Foundry Furnace, Generally Gas or Electric.
● The Fuel or Power Source for the Furnace.
● The Melting Pot or Crucible (vessel) that goes in the Furnace which holds the molten metal.
● Tools to Feed / Remove / Carry the vessel from the Furnace to the mold.
● The Cavity Mold or Ingot Form.
● The Dross or Waste Container.
Protective Clothing and Gear.
Protection from High temperatures require a safe working distance and shielding from the heat, spills and splatters. You must be protected from head to toe with these common safety items or more... Safety Glasses or Face Shield with Infrared / Ultraviolet Eye Protection, Heat / Flame Resistant Clothing, Welding or other High Temperature Gloves, Leather Work Boots or better. Remember just one drop of molten metal can cause serve pain or injury and guarding against the possibility of splatters or spills with protective clothing falls under precautionary procedures. Along with this comes safety gear such as proper tools to handle hot items and fire protection at hand such as a properly rated fire extinguisher. Remember water and molten metals can be dangerously explosive causing violent splatters, keep moisture away and out of the molten metal.
Infrared / Ultraviolet Hazards.
The most common types of radiation encountered in industry are infrared radiation (IR) or heat, ultraviolet radiation (UV), and bright visible light. Fire puts out UV and IR radiation to varying degrees per temperature. Sources of IR in industry are primarily molten materials, specifically glass and metals. Even though Foundry work generally has limited exposure to IR & UV both in time and intensity as compared to glass blowing or obviously welding its exposure should be reduced as much as possible with appropriate shielding. AOA (American Optometric Association) guidelines for UV protection recommend that sunglasses provide at least 99 percent protection from solar UV radiation (UV-A and UV-B) at wavelengths below 400 nm. Gray, green, and brown polycarbonate prescription sunglass lenses will provide this level of protection. Gray, green, and brown CR-39 plastic sunglass lenses may require a UV-protective dye to reach 99 percent UV protection. Gray glass prescription sunglass lenses do not usually meet this recommendation.
A Safe Work Area.
Your work area must be appropriate for both the type/size of furnace you are using and the type of casting being done. And it is imperative you have proper ventilation for both the exhaust heat and fumes generated by the fuels used and materials being burned up in the metal including metal vapors all of which can be toxic. Small furnaces designed for laboratory or jewelry work are common indoor furnaces but which still require remedies for heat and fume generation. Larger furnaces with bigger Melting Pots or Crucibles and higher melting capacities may require they be used outdoors only or indoors with very special surroundings where the high heat and fumes generated are safely vented away and can not accumulate causing risk of fire, explosions or toxic unsafe breathing conditions. This may seem like a common sense thing to know, but each year someone somewhere burns down their home cooking the holiday turkey the wrong way and or in the wrong place, yet many large broilers operate safely in restaurants designed to use them safely in mind.
The Foundry Furnace
There are many styles and types of foundry furnaces who's basic purpose is to reach the proper temperature needed to melt the type of metal being cast. The fuel sources are normally electric or propane gas, but can also be coals, electric arc, forced air natural gas, and oil to name a few more. The foundry furnace design and fuel source are the key to effectively handling the needed temperatures for metal melt points and vessel volume size. Lead for example melts at 621 deg F, Aluminum at 1,218 deg F, Gold at 1946 F, Copper 1,981 F and Cast Iron 2,300 deg F. That's a big spread between Lead and Iron in degrees, BTU's, Time, Fuel and the soundness of the furnace to be able to handle it. It is also why your Safe Work Area must match the work at hand and also be able to handle possible large spills by accident or vessel failure either in the furnace or on way to mold pour. Some people have taken this for granted with small indoor lab or hobby furnaces only to regret not preplanning precautionary procedures for spills with metals in the 2,000 deg ranges set free before them unplanned. So think containment and separation from heat always. Also, you will need ample power or fuel to be available to complete the melt / pour for the needed time without interruption. By matching the proper furnace to metal, volume, fuel, time, cost ratio, work environment you can obtain the results you want in a safe, cost effective manner with good results.
The Fuel or Power Source for the Furnace.
By their very nature fuels are powerful and can be dangerous. Care must be taken to handle each specific one properly in raw form and with it's by products of high temperatures and toxic fumes generated by the fuel and or off gassing of debris/metal vapors. Adequate ventilation is mandatory to channel and dissipate all this properly and safely. Even with electric power as fuel extra care must be given to handle high electric loads on circuits and wires for extended periods of time which will not cause other safety issues upstream of the furnace by wire overheating, electrical fires, or blown circuits during the casting operation. Vapor and liquid fuels require extra care to guard against potentially explosive leaks by leak testing prior to flame lighting and ventilation to dissipate any unknown fumes afterwards safely away from heat and flame.
The Melting Pot or Crucible.
The holding / melting / pouring vessel for the metal should be sized properly for the work at hand and of high enough quality to assure reasonable expectation of containing the molten metal from solid, to liquid, to pour with the understanding it can fail at any time by leak or catastrophic fracture. The truth is that the vessels are subjected to extreme temperature ranges which over time can weaken their molecular structure, or / and for metal vessels attack by the solvent action of melted metal burrowing through it, or softening under higher temperatures allowing punctures, or all vessels thermal shock cracking. The bottom line is to get the highest quality affordable but view all melting vessels as temporary limited life replaceable tools of the project which can be safely used even under failure conditions if planned for by spill catches (sand, dirt, containers, etc) and protective clothing & gear. Always use the proper vessel handling tools to lift, move, pour these vessels and handle genially to reduce shock as some are brittle while others soften with heat. Also, always inspect the vessel prior to using it for structural integrity, holes, cracks, etc. If safe usability is in question replace it with one that is safer.
Tools to Feed / Remove / Carry.
Some foundry operations use a variety of hand tools each with a specific purpose and some with multipurpose uses. The standards are to lift the vessel in / out of the furnace, another to carry and pour the vessel or one that does both by matching itself to the vessel / tool well. As you change vessels you may need matching tools for its new shape, size and weight. Also, you need metal tongs to pick up metal pieces to place into the melting vessel or move hot objects and another tool to stir the metal, still another to skim the slag off and out of the vessel to place the dross in its holding container. Another valuable and inexpensive tool is an infrared temperature gauge to quickly check if something is hot at a distance before touching.
The Cavity Mold or Ingot Form
This can be of many sizes and shapes of contained sand in forms which have cavities within them to pour metal into or open surface metal trays or ingot forms to pour metal into for bar or ingot shapes. The mold process can also include to material displacement processes call lost foam and lost wax molding. In the lost foam process, the desired end shape is in the form of foam which is encased in sand which burns out and replaced by molten metal, while the lost wax process is the desired end shape is encased wax then melted out by low heat to then leave the cavity. The normal sand only process is done by impacting a sand/clay mixture which holds together when squeezed like a snowball around the object to take on its reverse pattern. When the object is removed from the sand the void is then left to be filled by the liquid metal which then cools and hardens again.
The Dross or Waste Container.
In the process of melting metals especially scrap metals releases various amounts of impurities forming a solid mass that will start floating on the molten metal. This slag in liquid form is scooped or skimmed off the top of the metal then tapped off the tool into a collection container for later disposal or recycling. Remember this dross is the temperature of the molten metal which can explode trapped moisture out of concrete so don't tapped the dross off the tool onto concrete floor. Use a proper bucket, tray, or other safe collection bin for this hot substance to safely cool in.
- General Foundry Safety Rules -
Foundry furnaces (this item) work with high temperatures, molten metals and potentially toxic or explosive gases which can cause severe damage, injury, even death. It is your responsibility to educate yourself prior to the use of this with all that is needed for safe operation and advance preparation to handle mishaps just like you would any useful but potentially dangerous equipment. Even a common space heater gas or electric can be misused and safety precautions not adhered to for undesirable results, or it can be used properly and wisely given years of worthwhile desirable results.
-----------------
Propane fueled devices can reach temperatures up to 2040 deg Fahrenheit, 1,115 deg Celsius and hundreds of thousands of BTU's an hour. These temperatures heat both materials they come in contact with and the air around them for some distance including the exhaust gases being given off. Extreme care must be taken when working around these temperatures and to not let them come in contact with things not intended to be exposed to them and the time of exposure for things intended exposed.
DO NOT touch anything that is hot and always assume everything is, wear leather welding gloves or other high temperature gloves when doing foundry work.
Always use heavy duty melting pots / crucibles with appropriate working tools to handle them and the weights involved. Learn about safety, potential problems and safe procedures for handling mishaps or events in advance. Practice dry no heat pours before noting potential problems that may arise and how to best correct or handle prior to live high heat molten metal pours.
Remember: Even the finest most expensive crucibles can shatter or fail and at the worst time which is why using appropriate safety gear at all times is so important (boots, jeans, apron, gloves, face protection, etc.) and having an advanced safety plan in place is important.
For outdoor use only or safe well ventilated indoor area away from combustible / flammable materials including above furnace which can safely vent away hot and toxic gases / exhaust fumes without accumulation that also provides ample fresh safe replacement breathing air. Always have appropriately rated fire extinguisher available.
Fuel Safety: Never have propane bottle indoors during operations. Always check for gas leaks before use and monitor for leaks during use. DO NOT START FLAME OR OPERATE UNIT IF PROPANE ODOR IS DETECTED FROM LEAK UNTILL LEAK IS STOPPED AND CORRECTED. Propane is heavier than air and leaking propane can accumulate and pool in areas which can flash ignite. Always keep propane bottle at safe distance in open vented area and never operate a furnace, forge or kiln that is connected directly to a propane tank located unsafely near it, or indoors against safety code restrictions. An emergency pressure valve release in an enclosed area can instantly cause explosion and or place those close by in the middle of a fireball. Follow all local codes regarding indoor use of propane.
Never start furnace at high heat settings. Starting at a low heat then slowly gradually warm up furnace and melting pot / crucible (with contents) until proper operating working temperature is reached. Manually monitor unit and do not over heat the unit by using for overly extended periods of time or temperature.
Not For use by minors or individuals under the influence of alcohol or drugs. Keep others at a safe distance away from furnace, hot tools, molds, metals and work area.
Place on level ground with attention the drain hole purpose on concrete floor with catch basin for molten metal, loose dirt or sand away from moisture.
Never leave furnace unattended for any reason during operation. Turn furnace off. Turn Gas Supply off at source.
Always pour molten metal into proper molds, on sand or dirt floor. Molten metal spills on concrete floor causes dangerous results from trapped moisture in the concrete.
Do not operate near anything combustible / flammable.
During use, never introduce anything to the melt (liquid metal) that has not been preheated first. Always Pre-heat items in the exhaust flame or another source of heat.
A cold item or moisture placed into the molten metal will cause splattering and dangerous expulsions of molten metal!
- More Personal Protection -
Safety glasses / Shield with proper Infrared / Ultraviolet Eye Protection
Always wear proper eye / face protection.
Always assume everything is hot!
Always wear Hi-temperature protective gloves, heat protective clothing and safety grade leather boots / Shoes. Foot wares with laces are dangerous, cover-laced area.
Always make sure you are working in well ventilated areas with clean fresh air to breath and do not breath exhaust and metal fumes which can be toxic.
If you are unsure of something, learn about it in advance of doing, seek help and guidance when necessary.
Foundry furnaces (this item) work with high temperatures, molten metals and potentially toxic or explosive gases which can cause severe damage, injury, even death. It is your responsibility to educate yourself prior to the use of this with all that is needed for safe operation and advance preparation to handle mishaps just like you would any useful but potentially dangerous equipment. Even a common space heater gas or electric can be misused and safety precautions not adhered to for undesirable results, or it can be used properly and wisely given years of worthwhile desirable results.
-----------------
Propane fueled devices can reach temperatures up to 2040 deg Fahrenheit, 1,115 deg Celsius and hundreds of thousands of BTU's an hour. These temperatures heat both materials they come in contact with and the air around them for some distance including the exhaust gases being given off. Extreme care must be taken when working around these temperatures and to not let them come in contact with things not intended to be exposed to them and the time of exposure for things intended exposed.
DO NOT touch anything that is hot and always assume everything is, wear leather welding gloves or other high temperature gloves when doing foundry work.
Always use heavy duty melting pots / crucibles with appropriate working tools to handle them and the weights involved. Learn about safety, potential problems and safe procedures for handling mishaps or events in advance. Practice dry no heat pours before noting potential problems that may arise and how to best correct or handle prior to live high heat molten metal pours.
Remember: Even the finest most expensive crucibles can shatter or fail and at the worst time which is why using appropriate safety gear at all times is so important (boots, jeans, apron, gloves, face protection, etc.) and having an advanced safety plan in place is important.
For outdoor use only or safe well ventilated indoor area away from combustible / flammable materials including above furnace which can safely vent away hot and toxic gases / exhaust fumes without accumulation that also provides ample fresh safe replacement breathing air. Always have appropriately rated fire extinguisher available.
Fuel Safety: Never have propane bottle indoors during operations. Always check for gas leaks before use and monitor for leaks during use. DO NOT START FLAME OR OPERATE UNIT IF PROPANE ODOR IS DETECTED FROM LEAK UNTILL LEAK IS STOPPED AND CORRECTED. Propane is heavier than air and leaking propane can accumulate and pool in areas which can flash ignite. Always keep propane bottle at safe distance in open vented area and never operate a furnace, forge or kiln that is connected directly to a propane tank located unsafely near it, or indoors against safety code restrictions. An emergency pressure valve release in an enclosed area can instantly cause explosion and or place those close by in the middle of a fireball. Follow all local codes regarding indoor use of propane.
Never start furnace at high heat settings. Starting at a low heat then slowly gradually warm up furnace and melting pot / crucible (with contents) until proper operating working temperature is reached. Manually monitor unit and do not over heat the unit by using for overly extended periods of time or temperature.
Not For use by minors or individuals under the influence of alcohol or drugs. Keep others at a safe distance away from furnace, hot tools, molds, metals and work area.
Place on level ground with attention the drain hole purpose on concrete floor with catch basin for molten metal, loose dirt or sand away from moisture.
Never leave furnace unattended for any reason during operation. Turn furnace off. Turn Gas Supply off at source.
Always pour molten metal into proper molds, on sand or dirt floor. Molten metal spills on concrete floor causes dangerous results from trapped moisture in the concrete.
Do not operate near anything combustible / flammable.
During use, never introduce anything to the melt (liquid metal) that has not been preheated first. Always Pre-heat items in the exhaust flame or another source of heat.
A cold item or moisture placed into the molten metal will cause splattering and dangerous expulsions of molten metal!
- More Personal Protection -
Safety glasses / Shield with proper Infrared / Ultraviolet Eye Protection
Always wear proper eye / face protection.
Always assume everything is hot!
Always wear Hi-temperature protective gloves, heat protective clothing and safety grade leather boots / Shoes. Foot wares with laces are dangerous, cover-laced area.
Always make sure you are working in well ventilated areas with clean fresh air to breath and do not breath exhaust and metal fumes which can be toxic.
If you are unsure of something, learn about it in advance of doing, seek help and guidance when necessary.
This page of safety pointers is by no means intended to be all encompassing leaving nothing out but to help make you more informed and thoughtful about what you do in metal foundry work for your health and safety and that of others. This site assumes no responsibility for any information that is not present or present and how it is utilized by readers. It is your responsibility to educate yourself prior to taking on new projects and make it an on going education as you do it, to exercise sound work habits and safety procedures, and to practice them.
ADDITIONAL SOURCES OF INFORMATION:
OSHA - http://www.osha.gov/Publications/osha3151.pdf
Propane 101 - http://www.propane101.com
National Propane Gas Association - http://www.npga.org
Use Propane - http://www.usepropane.com
If you have more you would like to contribute to this page, feel free to submit it for review on our contact page. Know that in making these submissions you give permission for us to use the material as we see fit with no compensation due in return and free of restrictions, limitation.
© Copyright 2012.Golden Capital Resources / The Foundry Zone.