Do you have a wood repair project that requires holes or cracks to be filled?
On this page I’ll tell you how I make a wood filler using sawdust and glue here at the restoration shop.
It’s incredibly quick, simple and durable. Plus, a wood repair made with sawdust and glue is inexpensive and rewarding to know that it was done with a “like material”.
Before getting started I would like to mention that this filler is not recommended for any kind of structural repairs.
The image below shows a good example of where I often use sawdust and glue as a filler. This is the bottom of an upholstered chair that will be repaired with this technique.
Having been upholstered numerous times, you can see the rail was chewed up from all the tacks. To make sure new upholstery tacks will hold properly, I use a homemade wood putty mixed from sawdust and glue.
Super-long material list
- Wood glue
- Putty knife
Just about any wood glue will work to make this filler. Wood glue, hide glue and even epoxy glue. Because epoxy glue dries quickly, I use it on smaller repairs.
As for sawdust, my preference is the fine saw dust from sanding, rather than wood shavings which don’t mix well. I usually get it from underneath the disc sander and band saw.
I start by pouring glue into a small pile of sawdust and mix the two together with my putty knife. There’s no particular ratio or formula. It’s just a matter of adding a little more of either material until I get a desired consistency.
A well-mixed slurry of sawdust and glue will be workable enough to hold some shape, but not runny. A dry mixture will not adhere correctly, and a runny mixture will shrink and need additional applications.
As seen below, a thin layer of glue is put on the surface just before applying the wood filler. Doing this strengthens the damaged wood and helps the filler bond well.
Using the putty knife, the filler is applied by repeatedly packing it into the damaged area. Then smoothed out as best as possible.
This filler shrinks as it dries, so I leave excess to compensate. When filling deeper holes or cracks, I find it best to do more than one application to avoid air pockets.
Dry time varies depending on which glue is used and the size of the repair. I usually let dry overnight before preparing the surface for any finishing touches.
Once dry, the filler is very rough and sometimes jagged. Kind of like the texture of heavy tree bark.
The majority of this coarseness is quickly taken off with a file. Then I use sandpaper to smooth and flush. If I were repairing a different kind of surface, I might use a plane, or just sandpaper, and not a file.
Depending on the project, the filler may then need to be colored or touched up to help blend in. Since the rail on this project was going to be covered with upholstery, it was left as seen below.
Try it out. You’ll find it’s very durable and great for all sorts of wood repairs.