US3568739A

US3568739A - Rafter gauge

Info

Publication number: US3568739A
Authority: US
Inventors: Chester E Kirk
Original assignee: SPEED CUT Inc
Current assignee: PRODUCTION TECHNOLOGIES Inc A CORP OF OR; SPEED CUT Inc
Priority date: 1969-02-25
Filing date: 1969-02-25
Publication date: 1971-03-09
Anticipated expiration: 1988-03-09

Abstract

A device for supporting a rafter while a compound angle cut is made at one end thereof to fit other rafters in the fabrication of a roof. The device is adjustable so that rafters may be cut to fit roofs of varying pitches.

Description

United States Patent Chester E. Kirk Corvallis, Oreg. 802,154

Feb. 25, 1969 Mar. 9, 1971 Speed Cut Inc. Corvallis, Oreg.

[ 72] Inventor [21 Appl. No. [22] Filed [45] Patented [7 3] Assignee l 54] RAFI'ER GAUGE 2 Claims, 7 Drawing Figs. [52] U.S. Cl 143/170, 33/174 [51] Int. Cl B27b 27/06 [50] Field ofSearch 143/168, 169,170,174,132, 6-1; 144/288, 253; 33/174, 185; 83/468 [56] References Cited UNITED STATES PATENTS 1,789,125 l/1 93l Wilderson 143/174 2,274,129 2/1942 Collins 143/170 2,998,832 9/1961 Lewis 144/288 Primary Examiner-Donald R. Schran Attorney-Kimmel, Crowell & Weaver ABSTRACT: A device for supporting a rafter while a compound angle cut is made at one end thereof to fit other rafters in the fabrication of a roof. The device is adjustable so that rafters may be cut to fit roofs of varying pitches.

RAFIER GAUGE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the cutting of cheek-cuts on jack rafters, hip rafters and valley rafters, all used in the building of a roof and involvingcompound angle cuts which are most difficult to calculate and to accurately make. The device is used with a power saw of the type which is moved across the work, such as a radial arm saw, and supports the rafter at an angle to the upright fence.

2. Description of the Prior Art The cutting of the compound angle cheek-cuts on jack rafters, hip rafters and valley rafters in the construction of a roof has been in the past a laborious art in which the carpenter draws the compound angle on the piece to be cut and then hand saws the marked out with either a hand operated handsaw or an electric driven handsaw. Following a drawn line particularly for a compound angle is extremely difficult with either electrically operated saws or with hand operated saws so that it is almost impossible to get a good fit when cutting rafters with such a system. Furthermore, the accuracy of the total length of the cut is quite important and very difficult to maintain when following a drawn line on the work.

SUMMARY OF THE INVENTION The present invention consists of a gauge which is secured to the fence of a saw so that the work which is normally engaged flat against the fence is held outwardly at its upper end so that it is at an angle to the fence to produce an angle cut when the saw is moved thereacross.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an end elevation of the invention shown attached to a saw fence with a protractor illustrated in a position to check the angle of the workpiece; 1

FIG. 2 is a vertical cross section taken along the line 2-2 of FIG. 1 looking in the direction of the arrows with the workpiece removed;

FIG. 3 is a top plan view of the invention removed from the saw fence;

FIG. 4 is a plan view of the gauge bar illustrating one set of indicia;

FIG. 5 is a plan view of the opposite face of the gauge bar illustrating another set of indicia;

FIG. 6 is a top plan view of a sawand saw table with the invention attached thereto with a rafter in position for cutting to produce a left-hand rafter; and

FIG. 7 is a view similar to FIG. 6 .with the work in position for cutting a right-hand rafter.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several FIGS., the reference numeral 10 indicates generally a rafter gauge constructed in accordance with the invention.

The rafter gauge 10 includes a generally rectangular upright body 11 having a notch 12 formed in the lower end thereof. A bore 13 extends through the lower end of the body 11 and opens into the notch 12, as can be seen in FIG. 1. A bore 14 extends through the body 11 adjacent the upper end thereof with the axis of the bore 14 parallel to the axis of the bore 13. A threadedbore 15 opens through the top of the body 11 and intersects the bore 14 intermediate the opposite ends thereof. A setscrew 16 is threaded into the threaded bore 15 and has a handwheel 17 rigidly secured to the upper end thereof.

An elongated generally rectangular gauge bar 18 is provided at one end with a beveled point .19 and has a vertical bore 20 extending therethrough adjacent the opposite end thereofiA chain, 21 bis secured at one end to the gauge bar 18 through the bore 20iand at the opposite end engages about the threaded setscrew 16 to secure the gauge bar 18 to the body 11 so that it can not become lost.

A bolt B extends through the bore 13 and is adapted to extend through a fence 22 so that with a wingnut 23 the body 11 can be clamped to the fence 22, as can be seen in FIG. 1.

The gauge bar 18 has a surface 24 bearing indicia 25 consisting of the numbers 2 through 8 and a plurality of marks corresponding thereto. The surface 24 also carries the indication HIP and VAL. to indicate the type of rafter the gauge bar is to be used with. The opposite face 26 of the gauge bar 18 is provided with indicia 27 consisting of the numbers 2 through 8 and a plurality of indicator lines corresponding thereto. The surface 26 also carries the designation JACK to indicate this side of the gauge bar 18 is to be used for jack rafters. The spacing of the indicia 25 is somewhat different from the spacing of the indicia27 for the reasons as will be explained below.

The gauge bar 18 is adapted to be slid through the bore 14 and clamped in an adjusted position therein by the setscrew 16 operated by the handwheel 17.

In FIG. 1, a rafter 28 is illustrated in position against the fence 22 at its lower end and with its upper end held outwardly at an angle by the rafter gauge bar 18. A protractor 29 is illustrated in gauge checking position to determine the angle of the rafter 28 with respect to the fence 22.

In FIGS. 6 and 7, a radial arm saw is generally'indicated at 30 and includes a saw blade 31, an electric motor 32, drive belt 33, a saw table 34, and a fence 35 to support the work while being cut by the saw blade 31. The saw blade 31 is adjustable in angle and the angle can be read on a protractor dial 36. A left-hand rafter 37 is in position on the saw table 34 in FIG. 6 and is about to be cut by the saw blade 31: In FIG. 7, a rafter 38 is positioned on the saw table 34 to have the cheekcut made thereon to produce a right-hand rafter.

In using the rafter gauge 10 the following table is consulted to get the correct relationship between the pivot angle of the saw blade and the tilt angle of the work.

TABLE 1.COMBINATION OF ANGLES FOR CHEEK CUTS In the use and operation of the invention, the gauge bar 18 is turned so that the surface 24 or the surface26 is upward, de pending upon the type of rafter to be cut. The numbers of the

indicia

25 and 27 refer to the number of-feet of slope in 12 feet of the finished roof. The gauge bar is slid until the correct slope number is at the edge of the body 11 as illustrated in FIG. 3, whereupon the handwheel is tightened to clamp the gauge bar 18 in the body 11. With the gauge bar in the correct position, the saw angle is set to correspond to the slope of the roof to be cut and with the saw blade in a vertical plane, the saw is moved across the rafter which is in contact with the fence and the gauge bar in the position illustrated in FIG. 6 or FIG. 7.

Having thus described the preferred embodiment of the invention, it should be. understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit ofithe invention.

I claim:

1. The combination, with a saw support structure including a horizontal table and a fence substantially perpendicular to the table, and a vertical saw blade movable across the table, of a rafter gauge attachment comprising:

a body portion having an upper end and a lower end, the

lower end having a notch formed therein of a configuration to engage about the fence of the saw support structure;

means detachably securing the body portion to the fence;

the body portion having a first bore formed therein and extending therethrough above the fence and on an axis perpendicular to the fence;

an elongated gauge bar slidably mounted in the first bore for movement substantially along said axis;

the gauge bar having opposite faces and being provided on each of said faces with indicia for indicating cutting adjustments;

the body portion having a threaded second bore intersecting the first bore;

a screw, having an external handle thereon, engaged in the second bore and movable into contact with the gauge bar to clamp the gauge bar in adjusted position; and

means for flexibly securing the gauge bar to the screw.

2. The combination of claim 1, wherein the gauge bar has an end provided with oppositely beveled faces.

Claims

1. The combination, with a saw support structure including a horizontal table and a fence substantially perpendicular to the table, and a vertical saw blade movable across the table, of a rafter gauge attachment comprising: a body portion having an upper end and a lower end, the lower end having a notch formed therein of a configuration to engage about the fence of the saw support structure; means detachably securing the body portion to the fence; the body portion having a first bore formed therein and extending Therethrough above the fence and on an axis perpendicular to the fence; an elongated gauge bar slidably mounted in the first bore for movement substantially along said axis; the gauge bar having opposite faces and being provided on each of said faces with indicia for indicating cutting adjustments; the body portion having a threaded second bore intersecting the first bore; a screw, having an external handle thereon, engaged in the second bore and movable into contact with the gauge bar to clamp the gauge bar in adjusted position; and means for flexibly securing the gauge bar to the screw.