Is Your Miter Saw Square?

Is your miter saw square?

Q. I want to adjust my miter saw so it’s dead-on accurate, but I don’t have a fancy square. How do I do it?

A. Use an old woodworker’s trick: set up your saw as close as you can with whatever square you have (see photo below), saw a board in half (Photo 1) and flip over one side (Photo 2). When your saw is dead on, the two cut ends will butt perfectly together. If there’s a gap in the front of the joint (Photo 3), it means the saw blade is angled a bit to the left. If there’s a gap in the back, the saw blade is angled to the right. The gap itself is actually twice the amount that your saw is off, because you’re comparing two cut ends to each other.

Most miter saws can be adjusted by loosening some screws and pivoting the fence. Refer to your owner’s manual for details.

Click any image to view a larger version.

1. Cut a trial board in half. It must have absolutely straight and parallel sides. Secure it with hold-downs or clamps.

2. Flip over the right half, hold it tight against the miter saw’s fence and butt it up to the left half.

3. A gap between the two cut ends indicates the saw isn’t set square.The gap represents twice the error.

Don't do this!

Q. When I bought my first cordless drill, I was told to drain the battery all the way down before recharging to prolong the life of the battery. I used to clamp the switch until the drill quit running. Now I hear this is a bad practice.What gives?

A. Don’t drain your battery! Actually, you can stick your battery in the charger anytime you like.Draining the battery all the way down is a bad idea, for any drill, whether it has a NiCd or NiMH battery. The practice will cause heat to build up in the battery. This can actually shorten its life, just the opposite of what you intend.A good rule of thumb is to recharge the battery at the first sign of power loss. Let the battery rest and cool for 10 minutes or so before plunking it in the charger.

Attack of the powder post beetle

Q. I just noticed that my stack of airdried oak is peppered with tiny holes. I also noticed little piles of fine dust on and around the stack.What can I do to save my wood?

A. You’re probably looking at a powder post beetle infestation. These pests particularly love the sapwood in hardwoods like red oak and ash.The problem usually manifests itself when the beetles begin to exit the lumber in the springtime. They push the dust (called frass) that is packed into the holes out ahead of themselves.

You can help prevent future infestations by maintaining a tidy area around wood that’s air drying outdoors.Remove scraps, sawdust, vegetation, etc.

Once an infestation is discovered you have two choices.You can take the wood to a kiln to finish the drying process. Kilns will heat the wood to 140 degrees F or more and that will kill the beetles. Your other recourse is to have the pile fumigated by a pest control company.You may have to call around to find a company familiar with the problem.

This story originally appeared in American Woodworker January 2004, issue #105.

January 2004, issue #105

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