Refurbing a Scroll Saw

[paulrussell]

I believe there were some minor design flaws with the first generation scroll saw in respect to lateral slop in the arm bushings. This was partially remedied by adding spring washers to one side. The arm pivots were redesigned with the release of the teal version.
The root cause was twofold:
1) The axle shaft mounting post was too small a diameter to fully support and limit lateral travel of the bushing
2) The post was not machined and had somewhat of a "flat dome" shape that gave even more lateral play as the bushing could slip over the post.
My attempt to re-engineer involves machining the tops of the mounting posts flat and parallel to the body, and adding nylon sleeves to help limit bushing travel. One sleeve is smaller than the rest due to interference from the upper arm cover mount.
The lateral play is now gone, and time will tell how the nylon sleeves hold up.

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[paulrussell]

Later "Teal" scroll saws have a modified upper arm to eliminate interference with the knob on the blade clamp. The rightmost "finger" of the arm is deleted and the quick-release pin is replaced with a roll pin.
I went a similar route. After removing the "finger" I shortened the existing pin. Along with the original retaining clip and a small o-ring to prevent rattling, it is a perfect fit in the new location.

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