Band Saw Tune-up & Repair

Presentation By: Bruce Bogust

If you are a new member, or thinking about buying a new band saw the things to consider are: the vertical height in which the saw guides can be raised, the distance between the blade and the stand (called throat clearance), what material the wheels are made of and type of blade guides.  The saw blade needs weight to move the blade so steel or cast iron wheels are superior to the aluminum wheels. Roller bearing guides are better than the solid blocks.

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Club President Bruce Bogust repaired the shop band saw. The following is a guide in case your band saw wheel bearings are making a funny noise (worn) or if the rubber on the wheels is deteriorating and needs to be replaced.

First, many of the parts are specific to top and bottom wheels so take a photograph of your machine as a guide to reinstall the parts in their proper place.

Peel off the old rubber tire of the wheels. To install the new rubber wheel (also called a tire) work the rubber back on with the aid of a screwdriver. Sometimes heating the rubber SLIGHTLY with a halogen light will aid in the installation.

Again, the pulleys and bearings on the machine are sometimes specific so ensure you note how they are initially installed on the machine. Remove the nuts that hold on the wheels and bearings.

One can purchase the manufacturers bearings or order generic bearings (often at a lesser price) from companies such as McMaster-Carr.

You will need three measurements if purchasing generic bearings. Bruce is getting ready to measure outside diameter, the inside diameter of the hole and the width of the bearing (shown on the right). If you get a “funny” number upon your measurement, it is probably a metric size.

If installing the bearing on a shaft or axle first heat the bearing with a lamp (Bruce used a halogen lamp) Place some light oil on the shaft. Using a pipe that is SMALLER than the diameter so you do not damage the bearing, tape the new bearing onto the shaft

When installing bearings in a race, cool the bearing to aid in the installation. You may use a WOOD DOWEL to help tap it into place.

Spin the wheels by hand to ensure they are free to move and are balanced. The previous owner drilled holes in the wheels as seen here to balance them

Check to see if the pulley is keyed then Install it properly. Check to ensure the belt runs straight.

Assuming the floor is level and flat use a large level to determine if both wheels are straight (called co-planning). The level should touch the top and bottom of both wheels at the same time. If not a washer, smaller than the bearing can be used to make corrections.

Install the blade so the teeth point down (yes… people have done it backwards).

Adjust the tension of the blade using the scale on the side of the machine. Another way is the blade should “ring” when plucked.

Bandsaw-10Use a credit card or dollar bill to adjust the distance between the blade and roller guide or block guide. The roller guides are superior to a guide block. (Potentially your machine could be retro fitted). In addition, “cool blocks” are available from Woodcraft if to help keep your blade friction to a minimum.

The pin at the end of the table keeps both halves level. Run a straight edge across the it. If you hear, a “click” (meaning they are not level with the pin installed) either use a stone to level it or take it to a local repair shop.

Use a square to check the table is perpendicular to the table (most table adjustments are under it). From the Wood Show they cut half way through a piece of wood, turned the machine off, then turn the piece of wood upside down and attempted to slide it on the back of the blade. If it did not smoothly go into place, something was not straight.

Table adjustments are at the back of the table and set at the factory so they should not need any adjustment.

Use a square and draw a straight line on a piece of wood. Cut along the line with the assistance of the fence. The line and cut should agree. If not follow the manufacturer’s recommendations to square your fence. Some newer fences have adjustments on the fence its self.

Turn the machine on and place a stone on the BACK EDGES of the blade to round them off a bit. This provides for a smoother cut as the wood passes the blade.