Hot Topping

Hot topping are added to the tops of risers and pouring cups to help improve the efficiency of the riser. Hot toppings are either exothermic, insulating, or a combination of both. Hot toppings generate heat to help aid in the feeding of the casting. Once the exothermic reaction has finished, the crust formed causes an insulating effect preventing heat loss, improving piping, and effectively feeding the casting.

We offer a range of exothermic, insulating, and metal-producing powder hot topping. In addition, we provide hot toppings for ferrous and non-ferrous alloys. With various times for ignition, rate of burn, and amount of smoke generated, we have an option that will work for you.

Carpenter Brothers, Inc. has all the necessary products for your casting and shakeout operation. We have metal cleaners, slag coagulants, metal skimmers, and vacuum-formed skimmers to help ensure your castings are defect-free. In addition, we carry a wide range of pouring hand ladles and sampling spoons for ferrous or nonferrous applications. And after you have poured your casting, we have the right hot topping to apply. So take a look around; if you don’t see what you are looking for, give us a call or send us an email as there is a good chance we have it.

hot topping


Name Time for Ignition Rate of Burn (mm:ss) Smoke Odor Crust or Expanding Density Exothermic, Insulating, or Metal Producing Ferrous or Non-Ferrous
Exotop 500 4-5 sec 01:25 MED LOW Crust-Hard 70-80 Density Exothermic Ferrous
Expandex 500 3-4 sec 01:50 MED LOW Expanding-Soft 60-70 Density Exothermic Ferrous
Expandex 544 3-4 sec 01:15 LOW LOW Expanding-Medium 57-59 Density Exothermic Ferrous
Exotop 300S 6-7 sec 01:35 LOW MED Crust-Hard 60-70 Density Exothermic Ferrous
Exotop GLS 3-4 sec 00:40 MED LOW Expanding-Soft 55-65 Density Exothermic Ferrous
Exotop NF 1-2 sec 00:30 MED LOW Crust-Hard 85-90 Density Exothermic Nonferrous
Insultop 100 0-2 sec 00:45 NONE NONE No Change-Soft 32-36 Density Insulating Both


Foundry Products

We supply the necessary foundry products you need to make a quality casting. Whether you need Metals & Alloys, Melting & Melt Quality, Molding & Core Making, Casting & Shakeout, Finishing & Surface Preparation, or Environmental Compliance products, we have what you need.

Metals & Alloys

Alloys for Aluminum, Brass, Bronze, Gray & Ductile Iron, and Steel castings. 

Melting & Melt Quality

Everything you need to produce molten metal.

Molding & Core Making

Additives, risers, chaplets, chills, bentonite, resin systems, and coatings you need to make a quality casting. 

Casting & Shakeout

Products to aid you in casting and shakeout.

Finishing & Surface Preparation

Abrasives, carbide burrs, grinding and cutting wheels you need to process castings


PPE, dust control, baghouse, and waste management products to keep you in compliance. 

About Us

Carpenter Brothers, Inc. is the leading supplier of equipment, consumables, and technical expertise for the metal casting industry. Founded in 1917, by Everett and Milton Carpenter, the brothers were able to use their unique foundry experiences to solve the problem of the day: a reliable sand source.  They got their foot in the door by selling natural bonded molding sand, which was mined by hand, loaded into horse-drawn carts, and then delivered to customers.  Not only did they sell the sand, but their technical expertise was readily available for all customers, big or small, to help manufacture the best castings. After surviving The Great Depression, Carpenter Brothers, Inc. slowly increased the number of products it distributed and expanded its sales territory into what it is today.


Carpenter Brothers, Inc. has committed itself to its customer's success by providing exceptional service to go along with the superior products and equipment they supply.  With multiple warehouses around the United States we can get you the products you need when you need them. Our logistics team can handle getting your order to you by truck, plane, or train. Our technical sales and engineering staff all have experience in the industry, so when you buy from Carpenter Brothers you gain access to all of our knowledge.

Contact Us for a Quote

We are here to assist, give us a call or send us an email with your questions or quote request and we will be happy to help.