US Patent: 224,156
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Die for forming Double-Twist Gimlets
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Manufacturer: |
Not known to have been produced |
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Patent Dates:
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Applied: |
Jun. 20, 1879 |
Granted: |
Feb. 03, 1880 |
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Jeff Joslin (dm)
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Description: |
Increasing sized "bars" in the die deepen the pods (flutes), and "swell" the gimlet bit rod toward the tip - providing strength and clearance for the trailing portion of the bit. |
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