A whole LOT of uses for sawdust

I received an email from Adam Reed wondering if I had any suggestions for what to do with sawdust. Sure, we occasionally mix it with glue and make wood filler, but mostly it all goes into the garbage. It seems so wasteful.So I posted the question on the Mere Mortals Facebook page a got a bunch of good suggestions. But special kudos goes to Walter Masten who has already been compiling a list of ideas he has run across and has even taken the time to categorize them. I have taken the liberty to edit his list as well as add suggestions from people on Facebook and put them all in the following list.

I cant personally guarantee the veracity of any of these as they are tips from around the web, but most seem like reasonable uses for sawdust. Feel free to add any of your own in the comments section. I just hate throwing stuff away!Sawdust Uses in the Wood Shop

• Fill wood holes and defects. Used by professional floor refinishers, very fine sawdust or "wood flour" makes excellent, stainable filler when mixed into putty with wood glue. The wood flour from my sanders I put in small zip lock sandwich bags, label them as to wood type and save for project repairs or repairs to wood structures around the house.
• I occasionally go through my old cans of paint, finish, and stain to throw away. By law you can’t throw those as a liquid in the landfill. But you can if they are dry. I pour the liquids into a bucket of saw dust until it is absorbed nicely and let it dry. Then I dispose of it.
• You can pour them into moulds coated with wax to make stuff. You just need to mix them with a bit of resin. Turns out like MDF, except whatever shape you want. Paintable, stainable and super easy to sand and get a glass like finish on.
• I use mine to protect the concrete floor of my shop. I have found that a 50mm thick layer prevents scratching of the delicate concrete surface and deadens the noise of falling tools.

Sawdust Uses in the House/Body/Cooking

• Lighten up cement. Sawdust mixed into mortar has long been used when erecting cordwood walls to aid in bonding the logs together. Do the same when casting lightweight vessels and moisture-loving planters.
• Use wood shavings as a packaging material in place of Styrofoam peanuts, bubble wrap, and other synthetic material.
• Clean a floor. Moisten a pile of sawdust with water and use a push broom to sweep it around the concrete floor of your garage, basement, or shop. The wet sawdust will capture and absorb fine dust and grime.
• Cedar can be put in ziploc bags and put in closets.
• Pack a path. Tamp sawdust into a dirt walkway to curtail erosion and create a soft, fragrant pathway through your garden or wooded lot.
• For areas that get snow. Use untreated wood shavings for traction on sidewalks etc. better for the plants than using salt products.
• Get a grip. Winter loggers spread sawdust on their truck paths. It provides traction and strengthens compacted snow while protecting the ground underneath.
• Use sawdust to stuff decorative pincushions for gifts at holiday time. Pins and needles won’t rust.
• I use some of my hardwood shavings in my side fire box meat smoker for added flavor.
• Use sawdust for soaking up oil spills. Just sprinkle it on, let it sit for awhile and then sweep up. Sawdust can also be used to clean greasy, oily hands and tools. Sprinkle it on, massage thoroughly, and add more sawdust as necessary. Better than using messy newspapers or wasting paper towels.

Gardening with Sawdust:

• If you use a lot of sawdust in your vegetable garden it might turn your soil acidic. Plants need a somewhat neutral PH to be able to pick up nutrients, so add some lime. Do a soil test to determine how much lime. 
• Walnut sawdust contains an herbicide and will kill tomatoes and other plants.
• When using sawdust in gardens always add extra nitrogen, because the decay bacteria will use all available nitrogen and leave the plants with the “yellows.” Eventually the nitrogen is freed, but that may take a year or two. 
• The larger the pieces of wood, the less nitrogen starvation is a problem. 
• Chase away weeds. Sawdust from walnut wood is a natural weed killer. Sweep this variety between the cracks of your walkway.

Sawdust and Woodchips for Fuel

• We burn most of ours in the boiler to make the steam to dry wood.
• Mix it with wood chips and melted paraffin. Pour into empty tuna fish tins for emergency fuel or camp fire starter
• Another use for hardwood shavings and sawdust is in ceramic raku firings. It won’t use up great quantities of waste sawdust, but maybe you could get a free pot or two out of the deal, and it is fun to watch.
• How to build and use a sawdust stove
• The Fire Brick: I start with a large tub (about 2? * 15? * 15?) 3/4 full with sawdust. To this I add 15 – 20 litres (3-4 gallons) of the biodiesel byproduct and mix a bit. I leave this for a day or 2 and then mix again. I repeat this until the sawdust is evenly mixed. If it is too moist, I add more sawdust and mix this sawdust in the top layer. When I have sawdust which can be squeezed in my hand, and it retains its shape, but crumbles when pushed from the side or top, it is ready to be packed.
• Make a fire starter. Melt candle wax in a nonstick pot, add sawdust until the liquid thickens, pour into an empty egg carton, and let cool. Use the briquettes to help get a fire going.

Animal Woodchip and Sawdust Ideas

• Certain species of woodchips and sawdust make great bedding for cows, horses, chickens, pigs and other farm animals. Beware Black Walnut though… it’s highly toxic to animals.
• I also bag some red cedar up in burlap bags and sell them for $10 as dog bedding.
• As bedding for small mammals gerbils, mice, rats etc.
Sawdust Uses in Projects
• Make fake snow. Mix sawdust with white paint and glue to cover holiday crafts with simulated snow.
• Lighten up cement. Sawdust mixed into mortar has long been used when erecting cordwood walls to aid in bonding the logs together. Do the same when casting lightweight vessels and moisture-loving planters.
Sell or give away Your Woodchips and Sawdust
• I cut a lot of Eastern red cedar and I bag the sawdust up and sell it. I get $3 a plastic garbage bag; using kitchen bags (I believe they are 15 gallon). 
• Craigslist. Thanks to CL, I have a regular picker-upper now. I let her know, leave them out, and she hauls them away.
• Donate your sawdust to schools for use in pottery making classes. Some special firing techniques (e.g., the Raku process) involve packing the pieces in sawdust and firing in a pit.