68 - Our All-New Router Jig, страница 33
QUESTIONS & ANSWERS 5 GREAT USES Okay, so a dial indicator makes it easy to see really small measurements. What good is this for woodworking? Listed below are five ways I make use of a dial indicator in my shop. 1. Saw Blade Alignment - One of the first things I checked was the alignment of the miter slot to the saw blade. To avoid burned edges and rough crosscuts, it's important that the miter slot and saw blade be perfectly parallel to each other. You can do this by clamping the magnetic base to your miter gauge (the magnet won't work on most miter gauges) and then placing the tip of the dial indicator against the body of the raised saw blade (Figure 1). After zeroing out the indicator, slide the miter gauge to the back of the saw blade and check to see if the reading stays the same. It's a good idea to repeat this check after turning the saw blade to a different position. 2. Rip Fence Alignment - You can also get rough cuts when the rip fence isn't aligned with the saw blade. In Figure 2 you can see how to use the same setup to check the alignment of the rip fence. "What you're looking for here is that the measurements at the front and back of the rip fence match. Note: I actually prefer that the back of the fence is a couple thousandths further away from the saw blade than the front. This practically eliminates any chance of burned edges. 3. Square the Miter Gauge -Finally, to complete this quick table saw tune-up, the dial indicator can be used to square up the miter gauge. Figure 3 shows you how to use a drafting triangle to do this. You can even use this procedure for setting the head of the miter gauge at any angle — provided you have a triangle that matches. 4. Drill Press Table Alignment - Next, I took the dial indicator over to the drill press. It's a great way to make sure the table is perpendicular to the chuck. You can see in Figure 4 that the vertical rod from the magnetic base is installed in the chuck of the drill press. Now rotate the chuck by turning the belt at the top of the drill press (rotating the chuck itself can induce errors in the readings). The table is perpendicular to the chuck when the reading on the dial indicator is the same regardless of where it's positioned on the table. 5. Jointer Knives - One last thing a dial indicator comes in handy for is setting jointer knives (Figure 5). Simply start with the magnet in the base turned off, and the base and contact point resting on the outfeed table. Then adjust the indicator to read zero. With the knife at top dead center, reposition the base and indicator so the contact point is resting on the edge of the knife. The knife is set correctly when the indicator reads "zero" at any point along the edge.UlL Magnetic bast machined or bottom and b<.i for optional mounting Vertical rod allows indicator to be raised and lowered (or removed for use in a drill chuck) Internal magnet can be turned on and off with the flip of a switch Rotating joint and locking knob allows indicator to be swiveled to any position Spring joi allows sh rod to "bei forfine-tu? position i indicato Horizontal rod allows left and right movement of dial indicator Indicator attached tc short ro rotating joint and locking knob Magnetic Base FIRST; "zero out" pial indicator on outfeed table / outfeed table Setting Jointer Knives. A jointer knife is set perfectly when the height matches the reading of a dial indicator that's been "zeroed out" on the outfeed table. ----- t\ A Contact Points. A set of contact points with different shapes and lengths ensures you'll have just the right tip for your dial indicator. Drill Press Table. To square a drill press table to the chuck, tighten the vertical rod from the magnetic base in the chuck and then rotate the indicator by hand. FIRST: mount dial indicator in chuck so tip touches table SECOND: rotate belt by hand and check readings at various spots on table SECOND: position indicator over knife and verify dial indicator measurement is same No. 68 ShopNotes 33 |
