The AlbieCore™ "Lego block" pre-fab refractory blocks for masonry heater cores have been manufactured in Finland, Sweden and elsewhere in Europe for several years now. Newer systems (complete and partial kits) are also being manufactured in the U.S. and Canada. Tooling up to make "lego block" refractory kit systems is very expensive and these systems can only be made cheaply in volume. If you don't have a lot of capital, or a high volume demand, then jumping into the castable refractory kit business is very risky. Tess Fireplaces, the first American mass-produced modular system, went bankrupt and closed its doors. When Albie traveled to Finland in the fall of '92, one major modular firm there had just built a huge plant which was standing idle in Finland's 1992 economic slump. Since 1993, both a Canadian firm and a Swedish firm making modular core kits have undergone financial restructuring and ownership changes to remain in business. We decided that we would develop our own modular partial core kit system with very specific goals: (1) We wanted to simplify core construction. (2) We did not want to replace firebrick with castable elements where firebrick served as well, thus lowering manufacturing and shipping costs. (3) We didn’t want to become a major manufacturer or create a capital-intensive enterprise. (4) We wanted to demonstrate how to produce partial core kits efficiently and economically on a cottage industry basis. (5) We wanted to build something with long-term replaceability to stressed parts. Over the years we've built hundreds of heaters and identified four very labor-intensive areas in heater core construction. The first area was the firebox floor and the second was the sloping throat. The third area was the oven arch and smoke and gas splitting wedge atop the oven. The fourth area was the sloped shelf at the top of the heat exchange wall that supported the capping slabs. All of these labor-intensive details are discussed in print with drawings and photos in Albie's Finnish Fireplace Construction Manual and update. In the firebox area we found we could reliably and tediously build a firebox floor with a grate opening and cantilevered sloped outer wall for the expanded base channel and all of this held together well. More difficult was the addition of pitched walls at the firebox floor base, whose design function was to allow coals to fall toward the grate. Made up of additional carefully-cut firebrick pieces or castable refractory wedges, these sloped floors had a tendency to knock loose (not self-destruct) in a relatively short period of time. We decided that a firebox floor with built-in expansion joints, under-wall slope to the base channel, grate support, and a sloped floor for coals would be an important set of elements to create in a partial core kit. The rear sloping firebox wall is made up of a large number of mass-produced 60 degree skew cuts. These cuts are easy enough to crank out early in the job. The tedious part is cutting little slivers of constantly varying size on each course to back up the sloped pieces. Turning the corner with these pieces requires more careful custom cutting to lock in each course, and the back wall cantilevered pieces, because they are slightly top-heavy, want to lean into the firebox and pull each course out of level. We felt that an easier throat system would be advantageous, especially if we could create a throat that was replaceable and which made a see-through heater option possible without raising the overall height of the heater. We created the side slope design and found that it lent itself readily to modular design and replaceability, and also made the see-through option easier than the rear slope throat design. Casting an oven arch in place required lots of careful form work and expansion joints between the castable arch and the supporting fire brick. Building a smoke-diverting wedge on top of the curved top surface of the arch the next day was difficult as well and required several cuts, plus additional castable refractory fill under the wedge corners. With three forms we came up with a reversible oven design (front or back wall) with a one-piece smoke diverter wedge. Setting these three pieces in place became a fifteen-minute job rather that a three-hour job. Attaching the oven door hardware to these elements was also simplified. The fourth area of difficulty in our standard design is the sloped support for the refactory capping slabs. Noting that Tulikivi soapstone heaters are made in the order of 10,000 a year in Finland, we decided to pay attention to their core capstone design, which eliminates this sloped support. Now we cast a three-piece refractory slab set that rests on a double-gasketed layer of mineral wool on both the core front and rear walls, the smoke diverter wedge and the liner walls. We have had no difficulties with the new simpler design. The system drafts easily and cleanly. Our son, Scott, has been in charge of the AlbieCore™ manufacturing and packing process. We can at present produce one core a day and are continually upgrading the quality of the forms and subsequently the product itself. The Albie Core™ is now patented and available both as a partial core kit for people with local firebrick sources and a diamond saw, and as a complete kit with cut and uncut firebrick included for more remote customers. It is our intent not to go into mass production of the cores, but to encourage others elsewhere in the U.S. and Canada to work with us and set up similar cottage industry operations so that these 700 lb. kits can be manufactured locally. The AlbieCore™ The "throat" of a masonry heater. Core dimensions 27"D x 27"W with heat exchange channels and brick exterior overall dimensions are 36"D a 46"W $1650.00 The AlbieCoreSomeMore™ Extended version Dimensions are 31 1/2" D x 27" W with heat exchange channels and brick exterior overall dimensions are 40"D x 64"W $2250.00 In the meantime, we have recently struck a deal with one local trucker reducing our rates as a wholesale shipping customer by 45% so our freight costs, even over considerable distances, are now pretty reasonable for complete metal castings with an "AlbieCore™" order. Once the core is up and in place and the brick or stone veneer is around it, the entire throat can be replaced in about one hour with no damage to veneer work and no mortar required. A construction manual is available for building the AlbieCore™. Please visit our publications page for more info. Use your "back" button to return to the previous page, or choose from the menu at bottom of the page.

Contact us: Maine Wood Heat Co., Inc. 254 Fr. Rasle Rd. Norridgewock, ME 04957 Phone: 207-696-5442 Fax: 207-696-5856 E-mail: mwhcoinc@prexar.com

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