Auto Body Filler Is For More Than Cars
A winner for a variety of wood gluing and other repairs!
Auto body filler is an excellent wood filler and adhesive. It sets up quickly, has great adhesive properties. Unlike many softer fillers, it not only fills voids but can be cut and routed as cleanly as the original wood.
Auto body filler is a time-saver too! It can be applied, sanded and painted within an hour... a great time saver (and also saves my customer's the expense of a second visit). It is also weatherproof, waterproof and insect-proof.
Auto body filler sets gradually, proceeding through various stages of firmness, to a final extremely hard state. It is also temperature dependent and sets much faster in warm weather than in cool. If you are really impatient, setting time can be decreased by careful use of a hair dryer or heat gun. But don't overdo it or you may burn the adhesive!!
This gradual-setting characteristic requires vigilance... especially when your filler sets harder than the material you are filling. For instance, say you filled a hole in a piece of white pine and let the auto body filler fully set. When you tried to sand it, you would wear down the pine around the auto body filler patch and never obtain a flat surface. So you must stick with the job and check the hardness of the filler every couple of minutes, sanding smooth before full hardness is reached.
Ditto for shaped repairs. auto body filler works well with a planer or a knife while in intermediate stages of hardness, but is almost uncuttable with hand tools once fully set. However, if you are planning to work it with power tools, such as a drill, power saw, or router, you can let the patch set to full hardness without fear!
Because auto body filler sticks well to itself, you can build up your patches, filling a hole- level or slightly below- and then adding a "skim coat" to fill any imperfections from the first coat. If you prefer, you can also use other wood or wall patching materials with auto body filler to do that oh-so-critical final smoothing of the surface. Though there are thinner products for the "final coat" in fine automotive repairs, I haven't found these necessary for general household repairs.
When doing large repairs or deep fills, you can and should use pieces of wood to take up some space so you don't have to use as much filler. Putting a few screws into the material within the hole prior to filling will also add strength to the repair and keep the filler in place. The screw heads should be at least 1/8" beneath the projected "level" surface of the auto body filler repair.
Bondo ®, the original auto body filler, is manufactured by Bondo/Mar-Hyde Corporation. For your car repair buffs, Bondo has developed a one-part filler that is activated by ultraviolet light... either from the sun or better from a special lamp! I would advise against use of the "natural" method for those of you in the land of the midnight sun... especially during those loooong nights! Get the lamp, already!
Minwax produces a product known as High Performance Wood Filler. It is for all intents and purposes identical to auto body filler except that the color is a light brown wood tone. It comes in smaller packages than auto body filler and is quite a bit more expensive. I use this product for everyday repairs because of the conveniently sized can, but for the larger fill jobs I use auto body filler . It's always nice to save money, don't you think?