US 2982320 A
Description (OCR text may contain errors)
May 2, 1961 Filed July 30, 1959 A. L. TRUMBULL ET AL 2,982,320
OVERHANG FLUSH TRIMMER 2 Sheets-Sheet l 30 J INVENTORS. ALFRED L. TRUMBULL BY HELMER M. HALVERSON ZQWW ATTOWRNY f M y 1951 A. L. TRUMBULL ETAL 2,982,320
OVERHANG FLUSH TRIMMER 2 Sheets-Sheet 2 Filed July 50, 1959 f lry INVENTORS. ALFRED L. TRUMBULL HELMER M. HALVERSON ATTORNEY bottom panels.
United States Patent e,9sz,s2o OVERHANG FLUSH TRIMMER Alfred L. Trumbull, 104 SE. 87th Ave., and Helmet M. Halverson, 115 SE. 87th-A ve., both of Portland 16,
This invention relates to a trimming saw for cutting off a corner overhang in wood construction.
The present device is of general application in cabinet making and other types of wood construction but it is of particular advantage in boatbuilding. In applying plywood panels to a boat frame, for example, it is customary to apply the side panels first and then trim off the overhang flush with the chine strips before applying the When the bottom panels are nailed in place, the overhang on these panels must be cut ofi flush with the side panels or chines. Such cuts involve not only following the curvature of the chine but also making a bevel on the edge of each panel which varies in accordance with the angle between the bottom and side panels at different sections fore and aft. This workis usually performed laboriously with a hand plane which is a very slow and ineflicient operation; Where the corners are square or where the cut proceeds along a straight line as is often the case in general cabinet work, the overhang may be removed expeditiously in other ways but in fitting the curved lines and surfaces of a boat hull, the hand plane has been the only tool which could do the work, inefficient though it is. It is, therefore, the general object of the present inven-' tion to provide a novel and improved trimming saw to cut olf an overhang in forming a corner of wood construction.
Another object is to provide a trimmer for removing an overhang projecting over the corner of a curved surface.
A more particular object is to provide an overhang flush trimmer of the type described which will follow the curvature and variable angle of bevel involved in trimming the planking at the chine of a boat.
Another object is to provide a device of the type described in the form of an attachment for a standard type of portable drill wherein the drill motor is utilized to drive the trimming saw.
The present device comprises a frame which may form a part of a motor housing itself or may be constructed and arranged as an attachment to receive and clamp therein a portable electric drill motor. In either case the frame is equipped with a pair of feet adapted to slide on the surface of the work along the corner where the overhang is to be trimmed. When trimming the overhang of the bottom and side panels at the chine of a boat, the two feet just mentioned ride on the chine, chine strip or panel surface as the case may be and support the trimming saw in proper position to make the desired cut. The plane of the saw is further accurately fixed and determined by a third foot or by an attachable outrigger arm adapted to bear upon and slide along the keel. In this way the cutting side of the saw blade may be adjusted to trim the overhang substantially flush with the chine or chine strip so that a minimum of hand planing is thereafter required merely to smooth the sawed edge of the panel. The
device is adaptable to other types of wood construction where a similar problem exists.
2,982,320 t n ed Ma .61
The invention will be better understood and the foregoing and other objects will become apparent from the following description of certain preferred embodiments of the device illustrated on the accompanying drawings. Various changes may be made in the construction and arrangement of parts, however, and certain features may be used without others, all such modifications within the scope of the appended claims beingincluded' in the invention.
In the drawings:
Figure 1 is a side elevation view showing one form of the invention as it is used in connection with a conven tional portable drill; 1
Figure 2 is a longitudinal sectional view of the device of Figure 1 with the drill removed;
Fig. 3 is a cross sectional view on the line 3-'3' of Figure 1;
Figure 4 is an end view of the device shown in Figures 1 and 2;
Figure 5 is a fragmentary elevation view at right angles to the plane of the view in Figure 1;
Figure 6 is a cross sectional view on the line 6-6 of Figure 1;
Figure 7 is a view showing how the device of Figure 1 is used to trim an overhang;
Figure 8 is a perspective view of an auxiliary useon the device shown in Figure 1; and
Figure 9 is a fragmentary view showing the use of the auxiliary arm.
Referring first to Figures 1 to 6, the numeral 10 desig-' nates a conventional type of portable drill having a pistol grip handle 11 and a chuck 12 on a motor driven shaft to receive the shank of a drill bit or other small rotary tool. The device of the invention comprises, in general, a frame 13 which is arranged to clamp on the motor housing of the drill 10 and support a circular saw in opera tive connection with the chuck 12.
One end of the frame 13 comprises a yoke 15 adapted to encircle the motor housing of the drill as shown in arm for Figures 1 and 3. Yoke 15 is equipped with three clamp screws are made of a hard metal such as steel, depressions in the motor housing adequate for the present P1111- pose may be formed by the screws themselvesby merely tightening them against the housing with suflicient force the first time the device is applied to a particular drill. In subsequent usage, the screws may then be seated in the same depressions and will not tend to slip. Lock nuts '19 are preferably provided on the screws 17 and 18, but, for reasons which will presently appear, a lock nut is not usually necessary on the screw 16.
The frame 13 further comprises a pair of longitudinal tubular members 20 integrally connected at one end with opposite sides of the yoke 15. The other ends of tubular members 20 are integrally connected with opposite side edges of a longitudinal plate 21 which extends radially on opposite sides of a tubular bearing housing 22. Extending at right angles to plate 21 is a second radial plate 23.
The ends of plates 21 and 23 remote from yoke 15 are 27 having an end 28 adapted to fit the chuck 12-of the 3 drill. The other end of shaft 27 has an enlarged head 29 to carry the circular saw 30. In the present instance, the saw is connected with head 29 by screws 31 having heads countersunk in the saw blade so that there will be no grocjlection -on the outer or bottom surface of the saw As shown in Figure 3, yoke 15 has a central opening somewhat larger than the motor housing of drill so that the yoke itself does not touch the motor housing at any point. Clamp screws 16, 17 and 18 thereby provide a range of adjustment for the motor housing so that chuck 12 may be brought into accurate alignment with shaft 27. When the proper adjustment on all three screws 16, 17 and 18 is accomplished, lock nuts 12 are tightened on the screws 17 and 18. Then, when the drill is to be removed, it is necessary only to loosen the one screw 16. The next time the drill is to be used in the device, the locked screws 17 and 18 provide locating points to position the drill, whereby it is necessary in repeated use to tighten only the single clamp screw 16.
The position of the saw relative to the work piece is determined by three adjustable feet 31, 32 and 33 which form a tripod support for the saw. Foot 31 is formed as an integral knob on the end of a screw 35 having threaded engagement in an internally threaded tubular boss 36 on the plate 23. Screw 35 is frictionally held in adjusted position by a spring 37 which is compressed between one end of the boss and an adjusting knob 38 on one end of the screw. Twisting of the spring when the screw is adjusted is prevented by a washer 39 which is interposed between the end of the spring and knob 38. Washer 39 has a bent slotted tongue which straddles plate 23 so that the washer will not rotate with the screw. Spring 37 takes up any looseness in the threaded connection between screw 35 and boss 36 so that the screw will not be loose enough to rotate from vibration or from the movement of foot 31 over the surface of a work piece.
The other two feet 32 and 33 are rigidly mounted on the offset ends of a pair of rods 40 which are slidably mounted in the longitudinal tubular members 26. The remote ends of arms 40 are rigidly connected at 41 with the ends of a semi-circular sliding yoke 42 for movement in unison. The feet 32 and 33 are adjusted by a screw 43 having threaded engagement with the yoke 15. Screw 43 passes through a smooth hole in the semi-circular yoke 42 and is equipped with an adjusting knob 44. A compression spring 45 is mounted on the screw 43 between the yokes and 42 to take up any looseness in the threaded connection and hold the adjustment by friction. Thus, the feet 32 and 33 are adjustable in unison relative to the plane of the saw by knob 44, and the foot 31 is individually adjustable by knob 38. One of the feet 32 or 33 may be made adjustable relative to its rod 40, if desired, in order to make the kerf cutting side of the saw tangent to a curved surface when the tool is used on a curved surface of short radius as later described.
Figure 7 shows one application of the device just described. The two panels 50 and 51 have been connected together by means of a strip 52, and it is desired to cut off the overhang 53 of panel 51 flush with the surface of strip 52. This illustration may represent a part of a boat or cabinet structure, or the like. For example, panel 50 may be the side panel of a boat having a gunwale strip 52, and panel 51 may be an overlying deck panel. The same problem exists at the chine, considering the boat now as being upside down with panel 50 the side panel, 52 the chine, and 51 a bottom panel. To cut off the overhang as shown in Figure 7, the feet 32 and 33 are adjusted by knob 44 as close as is practicable to the plane of the saw. Then'foot 31 is adjusted by knob 38 to compensate for the thickness of strip 52 so that the saw will be in parallel with the plane of the strip when the strip is flat and ,alsoparallel to but spaced from the plane of panel 50. It -will be observed that this relationship is established independently of the angle which panel 51 makes with panel and regardless of any variation in such angle.
Further, because the saw is positioned relative to the Work by the tripod support afforded by the three feet 31, 32 and 33 which are relatively close together, the saw will faithfully follow the curvature of a curved chine as long as the operator holds all three feet in engagement with the work surfaces as the saw is advanced along the chine, the plane of the cut at all points being parallel with or tangent to, and substantially flush with, the surface of strip 52. When there is no strip 52, the overhang 53 may be cut off flush with the surface of panel 50 by adjusting foot 31 back to the same relative position as feet 32 and 33.
Figure 8 shows an outrigger or extension arm for use in certain types of construction where there is no surface available to provide a bearing for the foot 31. This extension arm comprises a rod having a along straight portion 55 and an offset portion 56 connected with a pair of spaced parallel end portions 57. Each end portion 57 is provided with a slotted head 58 equipped with a clamp screw 59. The slots in heads 58 are'made to fit the upper edge of plate 21 so that when clamp screws 59 are tightened on this plate the long straight end 55 of the arm extends laterally from the device in the plane of the saw as shown in Figure 9.
Figure 9 shows a portion of a boat frame in inverted position comprising a transverse bottom frame member 60, a keel or keelson 61, an upright side frame member 62, and a chine strip 63. In this case the side panel 64 has been nailed in place, but there is no bottom panel to support the foot 31 in the intervals between the transverse frame members 60. It is desired to cut off the overhang 65 flush with the bottom surface of chine strip 63, which is the top surface of this strip when the boat is inverted as shown. This is readily accomplished by causing the two feet 32 and 33 to ride on the chine strip while the arm 55 slides on the keel 61. This relationship is maintained around the curvature of the chine regardless of the varying angles between side panel 64 and the plane of the bottom panel which has not yet been applied. Foot 31 is retracted so that it will clear the frame members 60.
After the bottom panel has been applied on frame 60, the extension arm 55 is removed and the overhang of the bottom panel is trimmed as described in connection with Figure 7.
The feet 32 and 33 are preferably located close to a diametral line through the saw as shown in Figure 4 so that the saw can make the maximum depth of cut which is permitted by the radius of its hub portion or shaft head. The present invention is not limited to circular saws, however, since reciprocating saws of the saber type may also be used to advantage in certain classes of work.
Having now described our invention and in what manner the same may be used, what we claim as new and desire to protect by Letters Patent is:
1. An overhang trimmer comprising a frame containing a saw, a pair of spaced tubular members in said frame parallel with the axis of said saw, a transverse yoke connected at its opposite sides with said tubular members, means for clamping a portable power operated tool in said yoke in operative connection with said saw, a pair of rods slidable in said tubular members, feet on one end of said rods closely adjacent said saw, a transverse yoke interconnecting the other ends of said rods, means for adjusting said yokes toward and away from each other to adjust the position of said feet relative to the plane of the saw, and a third foot 011 said frame individually adjustable relative to said saw and closely adjacent to the saw.
2. An overhang trimmer comprising a yoke, a pair of spaced parallel tubular members connected at one end to opposite sides of said yoke and extending perpendicular to the plane of the yoke, means for clamping a portable electric motor in said yoke with its power output shaft extending between said tubular members in parallel relation thereto, a bearing tube mounted on the opposite end of said tubular members coaxial with the position of said output shaft, a shaft in said bearing tube having one end adapted for connection with said output shaft, a circular saw on the opposite end of said bearing tube shaft, a pair of rods slidable in said tubular members, feet on one end of said rods closely adjacent to the periphery of said saw, a yoke parallel with said first yoke interconnecting the other ends of said rods, means for adjusting said yokes toward and away from each other to adjust said feet relative to the plane of the saw, a third foot mounted on said tubular members adjacent to the periphery of said saw, and separate means for adjusting said third foot relative to the plane of the saw.
3. An overhang trimmer comprising a pair of spaced parallel tubular members, a transverse yoke on one end of said tubular members, said tubular members being connected with opposite sides of said yoke, means for clamping an electric motor in said yoke betweenv said tubular members, a bearing tube mounted between the opposite ends of said tubular members, a shaft in said bearing tube having oneend adapted for connection with a motor in said yoke, a circular saw on the opposite end of said shaft, a pair of rods slidable in said tubular members, feet on one end of said rods closely adjacent to the periphery of said saw, a yoke parallel with said first yoke interconnecting the other ends of said rods, means for adjusting said yokes toward and away from each other to adjust said feet relative to the plane of said saw, said saw having a segmental working zone on one side of said bearing tube defined by an imaginary chord line between said feet, the portion of the saw in said segmental working zone being capable of cutting and entering into a kerf in a work piece, a third foot mounted on the opposite side of said bearing tube closely adjacent to the periphcry of the saw, and separate means for adjusting said third foot relative to the plane of the saw.
References Cited in the file of this patent UNITED STATES PATENTS 751,820 Tons et al. Feb. 9, 1904 1,135,714 Pavelske et al. Apr. 13, 1915 1,206,461 Nickelson Nov. :28, 1916 1,216,340 Mattison Feb. 20, 1917 2,520,875 Birchmeier Aug. 29, 1950 2,714,905 Clayton Aug. 9, 1955 FOREIGN PATENTS 341,974 Germany Oct. 11, 1921