US4660A - Bat-tail file - Google Patents

Description

N.PETERS, PHOTO-LITHOGRAPHEH, WASNI-NGTOMID C.

UNTTED sTATEs PATENT oFFrcE- RICHARD FLINT, OF MERIDEN, CONNECTICUT.

RAT-TAIL FILE.

Specification of Letters Patent No. 4,660, dated July 24, 1846.

T all 'whom t may concern.'

Be it known that I, RICHARD FLINT, of Meriden, in the county of New Haven and State of Connecticut, have invented a new and Improved File; and I do hereby de- Clare that the following is a full and exact description.

The nature of my invention consists in the cut of the file.

To enable others skilled in the art to make and use my invention, I will proceed to describe its construction, I make my files by cutting a thread With clamp screw dies or by any of the known forms of cutting a screw tap, where a taper file is wanted I prefer cutting them in an engine as the feed can in that case be easily graduated, producing an equality of the thread through the large and small parts of the iile, and for a double cut iile I use a right and left hand thread.

Figure l, A A is a plan of a file cut as above described, the dark part of the figure represents the double cut part of the file,

the engine and use a ner thread in the'die,

for the left hand cut.

What I claim as my invention and desire to secure by Letters Patent is A round file or files cut by means of a right and left hand screw, or screws, substantially as above set forth.

- RICHARD FLINT.

Witnesses S. SMITH, L. GOODWIN.

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