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Two-saw Tuneup

By Jim Heavey
Invest a day in bringing your bandsaw and tablesaw back to peak performance.

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].

2SawTune-Arbor
Clean your face and take a seat. Remove debris stuck on the arbor flange with a putty knife and a bit of mineral spirits. A blade will rest flat against this freshly cleaned flange.

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. 

2SawTune-TiltGear
Access to these areas is tight, but cleaning the dust and pitch from between the teeth is vital to maintaining the tool’s accuracy and ease of use.

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.

2SawTune-WheelShaft
Keeping the wheel-shaft bearings lubricated will make turning the wheel to make adjustments a breeze.

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.

2SawTune-PhotoC
Pieces should slide smoothly across the throat plate. If the saw’s throat plate isn’t flush with the table, the inaccuracy will transfer to workpieces.

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.

2SawTune-Stop
On my cabinet saw, the 90° stop adjustment is at the end of the blade tilt gear. Loosening the jam nut and turning the hex bolt sets the correct angle. The 45° stop is at the opposite end of the gear.

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]. 

2SawTune-PhotoE

2SawTune-PhotoF
Slide from front to back. Use care when sliding the square so as not to damage the blade teeth. A gap or binding between the square and tooth means the blade is not parallel to the miter slot.

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. 

2SawTune-PhotoG
Rest the combination square against the right edge of the right miter slot. The square’s rule should touch the fence face at the rear as it does the front edge.

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°.

2SawTune-PhotoH
Apply painter’s tape to a plastic 90° triangle to help define the triangle edges and make any misalignment easy to spot.

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.

2SawTune-PhotoI
The splitter shown is sized to work with regular 1/8"-kerf blades. If you use both regular and thin-kerf (3/32"), you’ll need a separate splitter for each.

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].

2SawTune-photoJ
While turning each wheel by hand, angle a sanding block with 100-grit sandpaper to restore the radius. I check my progress often using a contour gauge until the tire matches the profile suggested by the manufacturer.

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].

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A couple of particleboard extensions allow my straightedge to reach the top and bottom of both wheels while clearing the saw frame. I had to remove the table to gain access to both wheels.

2SawTune-PhotoL
With the bottom wheel’s position fixed, use the tilt knob to align the top wheel.

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 14 " 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].

2SawTune-PhotoM
Don’t get too close to the teeth. Position the edge of each guide approximately 1⁄64" behind the blade’s gullets. The guides should never touch the teeth.

2SawTune-PhotoN
Wrap a piece of painter’s tape around the blade and gently press each guide against it to ensure the correct spacing between the blade and guides.

Next, adjust the thrust bearing. It rests behind the blade and stops rearward movement of the blade during cutting [below].

2SawTune-PhotoO
The space between the face of the thrust bearing and the back of the blade should be, as with the side guides, about the thickness of a strip of painter’s tape.

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.

2SawTune-PhotoP
Using a square, check the blade and adjust the table tilt to get that perfect 90° before locking it in place, and setting the stop and cursor at 0°. The higher you raise the guard, the more accurate the setting will be.

 

 

 

 

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