Whenever I look at my tablesaw and bandsaw, I think of that old Timex commercial that went, "Takes a licking and keeps on ticking." But even as dependable as that old Timex was, it would still lose a few seconds over time and would have to be reset. Such is the case with my stalwart tablesaw and bandsaw. Fortunately, the tune-up process doesn't take much time and returns their dead-on accuracy.
First tune up the tablesaw
My tablesaw is a cabinet-style saw, but the steps to tuning it up are much the same for a contractor-style saw.
First, crank the blade arbor to full height, then inspect and clean the faces of the arbor flange and the blade washer. This ensures that the blade seats well when reinstalled [below].
With the arbor raised, you can see the blade height and tilt worm gears and mating gear teeth [below]. These should be cleaned of all sawdust and old grease using a wire brush, compressed air, and, if necessary, a degreasing spray. I prefer using Gunk brand carburetor and choke spray cleaner; it works well to remove grease and varnish from metal parts.
When the parts are clean and dry, apply a dry-spray lubricant to the worm gears, teeth, and the trunnion (the mechanism that holds the arbor and blade) pivot points. For this, I prefer WD-40 Dirt & Dust Resistant Dry Lube spray. Last, apply penetrating lubricant to the hand-wheel shaft points and bearings [below]. Standard WD-40 works well for this.
Check the belts next. Replace cracked pulleys and frayed belts. While you're there, a good blast of compressed air into the motor will clear dust that can keep the motor from running cool. Now it's on to the top of the table.
To check for flatness, place a long straightedge across the width of the table and any extensions. Inserting thin brass shim stock (available in assortment packs online) at a couple of points between the extension and the table can change the "pitch" of that extension. Shims at the top of the joint lower the outside end of the extension; shims at the bottom of the joint raise the end. Tighten all connecting bolts and nuts. Then use that straightedge to ensure the saw's throat plate rests flush with the tabletop [below]. Most throat plates have screws for adjusting the plate up or down. A plate without these screws can be shimmed with pieces of painter's tape.
After reinstalling the blade, raise it fully and tilt it to its 90° stop. Confirm an exact 90° using a quality square, touching the blade body and the tabletop. Adjustments to the stop are done under the table. Find the stop's location [below] in the owner's manual. Use the same process to check the 45° setting of the blade and adjust its stop as necessary.
The last check of the blade is to assure that it is parallel with the table's miter-gauge slot. Place a combination square in the saw's left miter-gauge slot, resting against the right edge of the slot. Slide the rule to just touch a tooth at the front of the blade. Rotate the blade, moving the same tooth to the back of the table and use the square to check the distance there [below].
To fix a gap or binding, the process is different based on the type of saw: On a cabinet saw, slightly loosen three of the four bolts that hold the top to the base and pivot the top slightly. Then, retighten the bolts. On a contractor-style saw, the bolts are inside the saw underneath the top and a bit more difficult to reach. There, you'll be moving the trunnion instead of the table to adjust the blade parallel to the miter slot.
Now, in a similar fashion, use the right miter slot to align the fence [below]. Each fence has a different method of adjusting its alignment, and the manual will show you how.
Because the miter slot is used as a reference to align the blade and the fence, it makes sense to use it to align the miter gauge, too. A drafting triangle placed along the edge of the right slot will accurately square the face of the miter gauge [below]. Once set, lock the miter gauge's cursor (and stop, if any) at 0°.
Last, it's important to check the alignment of the splitter or riving knife. A properly placed splitter will all but eliminate any chance of a dangerous kickback. Whether it's part of the blade guard or an aftermarket stand-alone, the splitter must sit directly behind the blade and not extend beyond the edges of the blade. One of the simplest ways to check this is to lay two straight boards on either side of the blade and set the splitter evenly between them [below]. Recheck this alignment whenever the splitter is removed and reinstalled.
Finish up the tablesaw tune-up with a thorough cleaning of the tabletop and a coat or two of a non-silicone wax. This will inhibit rust formation while reducing the drag you feel when pushing stock across the table.
Now, strike up the band(saw)
Begin by backing off the guides to remove the blade. It's wise to wear a pair of thick work gloves and eye protection when handling these springy blades.
After thoroughly brushing and vacuuming off any embedded sawdust, inspect the upper and lower wheels. The tires on these wheels are made of rubber, neoprene, or urethane, and they should have no obvious tears, cracks, or checking. If they are very worn or have deep grooves, replace them.
In order for the blade to track correctly, the tires should be crowned. This slightly raised center section is where the blade rides during normal operation. If the tire has become flat from wear, re-crowning can be done in a few minutes using a sanding block and 100-grit sandpaper [below].
The wheels should also be checked to ensure they are coplanar. A long straightedge should touch the tops and bottoms of both wheels simultaneously in order for the blade to track on the center of both wheels [below]. Make any needed adjustments using the tilt adjustment on the top wheel [second photo below].
Reinstall the blade on the center of the tires and add tension while slowly turning the top wheel by hand. Minute tracking adjustments can be made by using the tilt adjustment until the blade tracks evenly at the center of both tires for at least two complete revolutions.
I have faith in my tension gauge. If you don't, raise the blade guard all the way and, using moderate finger pressure, check the blade's side-to-side deflection. It should deflect no more than 1⁄4 " at its center when tensioned correctly [Photo at top]. When the saw is not in use, remove all tension to preserve the integrity of the wheels and bandsaw frame.
Now, set the blade guides. The side guides keep the blade centered and eliminate twisting. With the blade under tension, adjust the upper guides (those above the table) [Photos below].
Next, adjust the thrust bearing. It rests behind the blade and stops rearward movement of the blade during cutting [below].
Repeat these steps when setting the lower blade guides. Hand-spin the wheels to check blade tracking and make any final adjustments before giving the blade a short test with the motor running.
Like the tablesaw, the tabletop must be set 90° to the blade [below]. Using a square, check if the bandsaw's fence sits perpendicular to the tabletop. To align my fence, I added a thin shim to the underside of my fence where it was bolted to its base. But having done that, I then had two tools that ran just like that old Timex watch.