Twiggy Springs

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Twiggy Springs

The Twiggy drive has 3 extension springs; here are some measurements from one drive (511347).

The extension lengths were measured where the attachment points pull on the hooked ends.

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A) Carriage Spring
This is the long spring that pulls the carriage forward to take up the backlash from the lead screw.

When the carriage is at the front of the drive, the spring extension is about 108 mm and the tension is about 101 g

When the carriage is at the rear of the drive (the eject position), the spring extension is about 140 mm and the tension is about 141 g

The spring is made from 144 turns of 0.28 mm wire with a hook at both ends, the coil has an outer diameter about 3.4 mm and weighs about 0.66 g

Tightly coiled section length of 40.0mm / 144 turns = 0.28 mm wire


B) Kickout Body Spring
This is the medium length spring that pulls the kickout body (KOB) forwards to eject the floppy disk.

When the KOB is at the ejected position, the spring extension is about 58.5 mm and the tension is about 87 g

When the KOB is at the disk-in-place position, the spring extension is about 71 mm and the tension is about 113 g

The spring is made from around 88 turns of 0.28 mm wire with a longer hook at both ends, the coil has an outer diameter about 3.5 mm and weighs about 0.44 g

Tightly coiled section length of 24.7 mm / 88 turns = 0.28 mm wire


C) Froggy Spring
This is the short length spring that pulls the froggy up when the floppy disk is unclamped.

When the froggy is at the unclamped position, the spring extension is about 26.5 mm and the tension is about 62 g

When the froggy is at the clamped position, the spring extension is about 39.5 mm and the tension is about 129 g

The spring is made from around 47 turns of 0.30 mm wire with a hook at both ends, the coil has an outer diameter about 3.45 mm and weighs about 0.27 g

Tightly coiled section length of 14.2mm / 47 turns = 0.30 mm wire