Band Saw Tension Adjuster Modification

I guess manufacturers (At least some of them) use the Tension Adjusting Type Knob shown in the Photo below, for economic reasons. But, boy is it a pain to use. Personally, I find myself using Channellock type pliers, to complete the tension tightening of the Band Saw blade.

Before going any further, the Band Saw I am modifying is a Sears Model No. 113.243311. It is a hand-me-down, given to me by a good friend who no longer had a need for it. Thanks Terry.

Now Back to the Tension Adjuster Issue
Not liking the tension adjusting knob noted above, I decided to alter it. I wanted a tension adjusting means, that would be relatively easy to adjust. The brainstorm that I came up with is shown in the Photo below. Ain’t she pretty ?

What is shown in the Photo above is a Rod Coupling Nut, generally used for coupling two 5/8″ dia. threaded rods together. The nail shown started life as a 16 penny common nail. The nail has been bent and cut to function as a cotter pin. Place a 15/16″ size socket & ratchet over the rod coupling nut, and you can tension & un-tension the Band Saw blade easily. I like using a ratchet with a 1/2″ drive. No strain whatsoever, when using a 1/2″ drive.

Good Riddance, Tension Adjusting Knob
First thing on my modification agenda was to remove the existing tension adjusting knob. It had decided it was not going down peacefully. I had to use a Dremel & cutoff blade, vise grips, and Channellock type pliers, to remove the knob. The two Photos below somewhat show the altercation that ensued.

Putting Together My New Tension Adjuster

Step 1 — Pictured below is a rough sketch with dimensions, of the shaft that the tension
adjusting knob was mounted on.

Step 2 — The ID of the rod coupling nut is 9/16″. However, I need an ID of 5/8″, and the
depth of the 5/8″ ID needs to be 5/8″. The two 5/8″ dimensions, referenced
here, are shown in the Photo above.

To enlarge the rod coupling nut ID, from 9/16″ to 5/8″, I used the Drill Press
Vise setup shown in the Photo below. The drill bit shown is a 5/8″ dia. bit.

Step 3 — Drilling Thru the Rod Coupling Nut
Remember the 16 penny common nail, shown earlier in this post, being used as a
cotter pin ? The two Photos below show the process I used, for drilling a 3/16″
dia. hole thru the rod coupling nut. The 16 penny common nail (Homemade
cotter pin) will be run thru this hole.

The Photo below shows pencil lines marking where to drill, the rod coupling nut.
Again this hole will be for the homemade cotter pin (16 penny common nail).

The drill press vise is shown setup in the Photo below, to drill the 3/16″ dia. hole
for my homemade cotter pin.

For drilling the 3/16″ dia. hole (Shown being drilled above), I used a two step
process. First, I used a 3/32″ dia. drill bit, and then used a 3/16″ dia. drill bit.

The drilling goes much faster using this two step drilling procedure.
Sketch #1 below, shows dimensional values for where to drill the holes thru the
5/8″ dia. shaft, and also for the 5/8″ rod coupling nut.

Step 4 — Drill the Shaft
First the rod coupling nut, the end with the ID enlarged from 9/16″ to 5/8″, is
inserted over the 5/8″ dia. portion of the tension adjusting shaft. This is shown
in the Photo below. I used the 3/16″ dia. hole in the rod coupling nut as a guide,
for where to drill thru the shaft.

I wrapped a paper napkin and electrical tape around the tension adjusting shaft,
as shown in the Photo above. My reasoning for this move and closing the Band
Saw housing door, was done to keep metal shavings from getting to the band Saw
blade wheel bearings.

The shaft drilling process went as follows:
1) Place the rod coupling nut over the 5/8″ dia. portion of the tension adjusting
2) Insert a 3/16″ dia. drill bit thru the 3/16″ dia. hole, that was drilled, in the
rod coupling nut. Next run your drill briefly to mark the shaft, to be drilled.
3) Now remove the rod coupling nut from the shaft. Using the mark left on
the shaft, drill a 3/16″ dia. hole thru the shaft. Again, use the two step
drilling procedure, noted in Step 3.

First drill using a 3/32″ dia. drill bit, and then finish by using a 3/16″ dia.
drill bit.

The Photo below, shows the rod coupling nut mounted on the 5/8″ dia.
portion of the tension adjusting shaft. The 3/16″ dia. holes shown, thru the
rod coupling nut and the tension adjusting shaft, will be used for my
homemade cotter pin.

Step 5 — Cotter Pin Time
This last step is a piece of cake. Just line up the holes in the rod coupling nut
and the shaft, and run a 16 penny common nail thru the lined up holes. This is
shown in the Photo below.

Next use a pair of Channellock type pliers, to bend the 16 penny common nail
(My homemade cotter pin). Bent cotter pin is shown in the Photo below.

After bending the cotter pin as shown in the Photo above, use a Dremel & cutoff
blade to cut the nail. Goal here is to match approx. what you see in the 2nd
Photo at the top of this post.

Modification Completed
Now all you need is a 15/16″ socket and ratchet placed over the rod coupling nut, as shown in the Photo below. And now, you can easily tension and un-tension the Band Saw blade.


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Until Next Time, Take Care