Wood pellet heating fuels, made from lumber mill bi-products such as sawdust, are growing in popularity as an alternative energy source, due to their convenience, high net energy return and relatively low price. Wood pellets typically require a specially engineered appliance to burn efficiently, such as a pellet stove, furnace or fireplace insert. For those who already have wood-burning stoves or wood-burning fireplaces but that want to use pellets as fuel, a special converter can be built to maximise air flow around the pellets, allowing them to burn effectively.
- Skill level:
Things you need
- 1-inch wide steel or aluminium flat stock, 2 feet
- 1/2-inch wide steel or aluminium flat stock, 5.5 feet
- Expanded diamond steel lath, 6 square feet
- Metal hacksaw
- Electric drill
- 1/4-inch bolts, 8
- 1/4 inch hex nuts, 8
- Leather gloves
- Tin snips
- Permanent marker
- Straight edge
- Metal scribe
- Wood pellets
- Gel or wooden fire starter
Cut two, 12 inch lengths of 1-inch steel or aluminium flat stock with your metal hacksaw.
Drill a 1/4 inch hole through the face of the flat stock, 1/2-inch in from the short edge. Drill a second hole on the opposite end of the flat stock, 1/2-inch in from the other short edge.
Repeat the drilling process for the other 12 inch length of flat stock so that you have two identical pieces of metal with identical holes.
With your metal hacksaw, cut 2 thirty-three inch lengths of 1/2-inch flat bar.
Place your first piece of flat stock on a level surface and mark a point on its face 12 inches from the edge with your metal scribe. Mark a second point 3 inches to the right of the first point, then another point 7 inches from the second and a final point 3 inches from the third.
Drill a 1/4-inch hole through the face of your flat stock, 1/4-inch in from the short edge. Drill another hole 1/4-inch in from the short edge on the opposite end of the flat stock. Drill a third hole through the face of the flat stock, 18.5 inches from the short edge.
Slide your flat stock into the jaws of your vice until the first point that you marked at 12 inches is level with the top of the jaws. Tighten the vice at this point and bend the flat stock downwards, forming a 45 degree angle.
Loosen the jaws and remove the bent flat stock. Insert the end on the other side of the bend into the jaws and slide the metal down until the jaws line up with the second point that you marked, 3 inches away from the first. Tighten the jaws and make a 135 degree bend in the opposite direction. The piece of flat stock will now look like an odd "L" shape
Loosen the jaws and slide the flat stock down to the third point that you marked, 7 inches from the last. Make another 135 degree bend here.
Loosen the jaws and slide the flat stock down so that the vice is lined up with the last point that you marked, 3 inches from the last point. Bend the flat stock at a 45 degree angle in the opposite direction from the last bend that you made. The flat stock will now resemble the letter "W" with a flattened out and elongated middle section and vertical sides.
Repeat this entire drilling and bending process with your second piece of flat stock until you have two identical "W" shaped pieces.
Assembling the Frame
Put on your leather gloves and use your tin snips to cut a 12-inch by 32-inch rectangle out of your expanded steel lath. Measure 11 inches in from the shorter side of the rectangle and mark a point with your permanent marker. Draw a line vertically down the centre of the rectangle at this point, parallel to the short side. Hold your straight edge against this line with your right hand and with your left, fold the material on the other side of the line over, making a 90 degree bend.
Measure a point 10 inches to the right of the first bend that you made and make another vertical line with your permanent marker. Hold your straight edge against this line with your left hand and use your right to bend the other side upwards at a 90 degree angle. Your piece of steel lathe will now resemble a hard "U" shape with one side several inches shorter than the other.
Cut two 12-inch by 12-inch squares out of expanded steel lath, which will form the sides of the basket. Cut a 1-inch slit in each of the 4 corners on both pieces and then fold the edges inward on three sides, forming a shallow tray with one open end. Place the side pieces on the open ends of the basket so that the folded down edges overlap the front, back and bottom slightly. Adjust the folds as needed to ensure a fairly snug fit on both sides of the completed basket.
Cutting and Folding the Basket
Take one of your 12-inch pieces of flat stock and hold it up against the back of the basket, up against the top edge on the outside of the basket. Fold the metal lathe down and around the flat stock as if you are rolling the metal up into a sheet.
Repeat this process with your second piece of 12-inch bar stock on the front of the basket.
Line up the top holes on one of your support pieces with the holes in the flat stock on the front and back of the basket. You may need to use your drill to push aside the mesh that is blocking the two holes. Slide a 1/4-inch bolt into the hole in the support piece, through the first layer of mesh and the flat stock and out through the other piece of mesh, attaching the frame to the side support and the mesh basket. It is vital that you connect both the main basket piece and the folded over edges of the side pieces to the support pieces. Secure the bolt in place with a hex nut. Bolt the other side of the support in place in the same manner.
Repeat Step 3 for the frame piece on the other side of the basket so that the support pieces are bolted to the frame which in turn support the mesh basket.
Slide a bolt up through the hole in flattened bottom of the support piece and into the bottom of the basket and secure it in place with a hex nut, preventing the legs of the support from bending outwards under stress. Slide a bolt through the hole in the other support in the same manner and secure it in place with a hex nut.
Securing the Frame to the Basket
Place your pellet burner inside of your fireplace or wood stove so that the front (the shorter end of the basket) is pointed towards the door.
Fill the basket up to the rim with high quality softwood or hardwood pellets.
Place a commercial wooden fire starter on top of the pellets or use a small amount of gel fire starter to light the pellets. Open the draft all the way on your fireplace or wood stove until the pellets have fully caught on fire. Close the draft to about half way to allow the proper circulation of air around the pellets, ensuring an efficient fire.
Using Your Pellet Burner
Tips and warnings
- Depending on the size of your fireplace or wood stove, you may wish to scale this project up or down to build a pellet burner that is right for your application.
- Be sure to clean any ash or dust left over from your pellet burner once all flames and embers have been extinguished.
- Expanded steel lath has extremely sharp edges. Leather gloves and eye protection should be worn at all times when handling or cutting steel lath.