The construction of the parts in immediate connection with the front cutter head is shown in Fig. 3184. n is the frame corresponding to n in Fig. 3183, the rolls 5 and 6 also corresponding in the two figures.
Upon n is a slide s having an arm g, carrying the roll g′, which holds the timber down to the cut of the cutter head k′. The pressure of roll g′ to the work is given through the medium of the rod a′, which receives the pressure of the equalizing bar x, Fig. 3183.
The bottom surface of the timber passes over the bed plate u, Fig. 3185, which raises and lowers with the lower feed rolls, being connected by the screw i, Fig. 3184, to the bearing box of feed roll 6.
All the lower feed rolls are operated simultaneously by means of the rod l, having for each lower feed roll a worm, driving a worm wheel l′ on a screw threaded into a hub m in each feed roll bearing; the crank for operating l is seen at p, Fig. 3183.
The passage of the timber through the machine is continued in Fig. 3185, in which it is seen that after the lower surface of the timber has been planed it passes from the cutter head k′ to a bed plate v and is thus supported by a flat and true surface while the side cutter heads plane the two sides, one of these side heads being shown at h. The side heads are carried in hangers, one of which is shown at p′. It is gibbed to the under cutter frame u′ by the sliding gib x, the left hand head h being moved across the frame by the screw f′. The hanger is held at the bottom by the gib t and the cross tie t′. p is the pulley for the side head h, the end wear of whose shaft is taken up by the adjusting screw s′, r′ being a leather washer, and r the end of the shaft.
The top box h′ moves across the machine in the slideway b′′, Fig. 3186, a′′ being a part of the box h′.
Upon leaving the side heads the timber will have been planed on three sides and the side surfaces dressed to a right angle with the bottom surface.
It is then guided to the upper cylinder as follows:
The friction rolls k, k are to relieve the bed a′′ from the pressure due to the feed roll z′ and the roll j′, which holds the timber after it has left the cutter i′, and thus prevents it from vibrating. After leaving the pressure roll j′, the timber passes under the scraper d′, Fig. 3183, and thence to the delivery roll 7, which is held down by the weight l, in connection with the lever l′.
By means of this construction all the cutter heads act upon the timber within the short distance of 221⁄2 inches, while the side heads act within 81⁄2 inches of the under cutter. This is desirable, being conducive to the production of true work, which it is more difficult to produce in proportion as the cutter heads are wider apart. This machine will joint as narrow as 2 inches, and plane as thin as 3⁄4 inch.
The upper cylinder i′, Fig. 3183, is adjusted for height or thickness of cut by means of the screw f, and is locked in its adjusted position on d by the nut i.
The feed is started or stopped by operating the hand wheel o′.
The upper rolls are raised or lowered simultaneously by power, by means of the shaft s, and the bevel gears r, which operate the screw a′.
The upper cylinder is driven by belt from the pulley q, the under cylinder from q′ (both these cylinders being driven from both ends). p′ is the driving pulley for the feed belt, which passes to n′, which, through k′′ and y′, drives y, which drives the feed rolls.
The machine will feed from 25 to 60 feet per minute.
PANEL PLANING AND TRYING-UP MACHINE.
This class of machine is employed for the production of true surfaces, and is now used upon much of the work that was formerly assigned to the Daniels class of planing machine. In this machine, as in the case of the Daniels planing machine, the work is secured to the table, which travels to carry the work to the feed.
Fig. 3187 represents a machine by J. Richards, in which a cutter head with skew cutters is employed, and a pressure roll is placed in front and at the back of the cutter head, the construction being as follows:
| VOL. II. | TRYING‑UP MACHINE. | PLATE XXVI. |
| Fig. 3187. | ||
Upon the main frame are the slideways t, t′, upon which the cross-head or cutter head frame z is carried, the elevating screw s raising or lowering the frame z, to suit the thickness of the work. The cutter head c, whose driving pulleys are shown at p, p, is carried in frame z, which also carries the pressure roll in front of the cutter (the bearing for this roll being shown at r), and a similar roll behind the cutter. To the frame z are pivoted the pressure bars b, b′, weighted with weights w. These bars rest on the cross-heads y, whose pins p act on the bearing boxes of the pressure rolls.
The cutter head frame may be raised or lowered, for varying thicknesses of work, either by hand or by power. The hand movement is obtained from the hand wheel w, Fig. 3188, which operates bevel gears b′′ and b′, the latter being threaded to receive the elevating screw.
The power or belt motion for raising or lowering the cutter head frame is obtained from rope wheel w′, which receives motion from the guide pulleys shown in Fig. 3187. The wheel w′ drives its shaft by the friction cone of its bore, which is forced against the corresponding cone on the shaft by the hand nut l. The handle v, Fig. 3187, is for operating the upper guide pulley q, which acts as a belt-tightening pulley as well as a guide pulley, and the hand wheel t holds v in its adjusted position. When v is pushed downwards the rope (e) is loosened upon the pulleys, and both rope and pulleys remain idle.
The pulley that drives rope e is shown in Fig. 3189 at r.
The feed motions for the work table are shown in Fig. 3189, and the construction is such that for ordinary work the table has a quick return motion, while for heavy work the feed and return motions of the table are speeded alike.
The driving pulley b, Fig. 3189, for operating the feed mechanism, receives motion by belt connection from the countershaft, and drives the shaft on which are the bevel gears b and d, and from these gears the feed motion and quick return are derived, while from gear e and pulley r the cutter head may be raised and lowered by belt power as occasion may require. Beginning with the feed motion, the gear d drives gears e and f, which are a working fit on the shaft s. Between these two gears is the clutch r, r, which is operated by the handle shown in the perspective view, Fig. 3187, at v.
To operate the feed, clutch r is operated to engage gear e with the shaft s, upon which is the friction wheel m, which engages with the internal surface of the wheel or drum g, which drives the rope wheel a, which drives the rope for the work table traverse—wheel a and the rope being seen in the perspective view, Fig. 3187. The shaft n has bearing in a piece that is virtually a sleeve eccentric, because its bore is eccentric to its circumference; to this sleeve is attached a lug h′ to which the handle h, Fig. 3187, is bolted. Now suppose that handle h is depressed, and then g will partly revolve wheel g and cause it to engage with the friction wheel m, which will drive g, and therefore a.
Diametrally opposite to m is a friction wheel n, which is driven by the bevel gear c, and which is brought into or out of action with g by the eccentric action of sleeve g, it being obvious that when the sleeve g moves g in the direction of n, m is engaged and n disengaged from contact with g. Raising the handle h therefore places n in gear with g, which revolves it in the direction necessary to draw the work table on the back or return stroke.
The return motion of the table is more rapid than the feed motion because gear c is of smaller diameter than b, and n is larger than c and than m.
In the case of heavy work, however, the return motion may be made to have the same speed as the feed motion by simply moving the clutch r so as to engage wheel f with the shaft s.
The rope groove in the pulley a is waved as denoted by the dotted lines, and this prevents the rope from slipping, notwithstanding that the rope envelops but half the circumference of a. The wire rope from a operates a drum, in which are waved grooves for the table traversing rope which winds around this drum, and attaches to pins (k, Fig. 3187) carried in brackets at the ends of the table, and one of which is shown in Fig. 3187, at z.
The slack of the rope is readily taken up (as occasion may require) as follows:
The pin k, to which the rope is fastened, has at one end a squared head to receive a wrench to revolve the pin and wind up the rope, set screw l locking the pin after the rope tension is adjusted.
We have now to explain the method of holding the work, which is as follows:
The side frames forming the bed are bolted to the main frame and form the ways on which the work table travels. The table frame j, Fig. 3187, is provided with rollers, which rest on the upper surface of the bed and reduce the friction.
The table is made in convenient sections bolted to the table frame j, and at their points of junction the work-holding dogs are placed, the construction being shown in Fig. 3190, in which t′ is the end of one, and t′′ the end of another section of the table. Referring now to Figs. 3187 and 3190, upon the edge of the table are the abutment pieces a′, a′′, against which the work is pulled by the dog, which is operated by the screw, which is squared at its outer end to receive the handle m, Fig. 3187.
The rate of work feed is 30 feet per minute and the quick return motion is 60 feet per minute.
MOULDING MACHINES.
In moulding machines for light work the feed rolls and cutter head overhang the frame, such machines being designated as outside moulding machines.
Fig. 3191 represents a machine of this class constructed by J. A. Fay & Company.
The table t slides on vertical ways on the main frame, being adjusted for height by the hand wheel w.
The work while fed over table t is pressed against the vertical face a by the four springs shown, whose pins swing to suit the width of the work.
The two feed rolls are made up in sections or discs and the pressure bar is pivoted and has the weight shown to adjust its pressure to suit the work, and is combined with the bonnet whose shape throws the shavings outwards from the side of the machine. The particular machine here shown is constructed substantially enough to permit of its being used for light planing or work not exceeding 6 inches in width, a head with planing knives being shown in place on the machine. In a machine of this kind it is essential that the cutter head spindle and its bearings be rigid, and with ample journal bearings and free lubrication to prevent wear, and for these reasons the arbor is of steel running in self-oiling bearings of large diameter. The arbor frame is capable of lateral movement to enable an accurate adjustment of the cutters to the work.
The term sticker, as applied to a machine of this class, means that it is suitable for light work such as window sash and door stiles, blind slats, etc., etc.
Fig. 3192 represents a machine termed by its manufactures (the Egan Company) a “double head panel raiser and double sticker combined.” The term panel raiser means that the edges of the work may be dressed down so as to leave a raised panel. To fit the machine for such work the bed or table t is made wide.
The upper feed rolls are in sections, and the lower one extends nearly across the bed. The upper feed rolls are held down by a spring, whose tension may be regulated by a hand wheel with an adjustment at the back end to give a lead to both rolls. By this is meant that the plane of revolution of the feed rolls inclines toward the cutter head so that as the rolls feed they exert a pressure on the work, holding it securely against the face a.
A long spring extends from the front of the feed rolls past the back or bottom cutter head, passing as shown beneath the pressure bar, and is adjustable for height from the bed or table face t by having its ends pass through two studs in which they may be secured by set screws. This serves to keep the work down to the surface of t.
The cutter heads for panelling have three cutters set askew or at an angle to their plane of revolution so as to give a more continuous and a shearing cut, which is conducive to smooth work.
The bed above the lower cylinder is adjustable for height by means of the screw at h.
MOULDING CUTTERS.
In the ordinary or common form of moulding cutter, the front face is flat and the lower end is bevelled off and filed to shape so as to give the required shape and keenness to the cutting edges, Fig. 3193 giving examples of such cutters.
Cutters of this class must be sharpened by filing the bevelled edge, which requires considerable skill in order to preserve the exact shape of the moulding.
SOLID MILLED CUTTERS.
In the solid milled cutter the bevelled surface at the cutting end of the cutter is a plane, and a curved, stepped or other shape is given to the cutting edge by cutting or milling suitably shaped recesses on the front face of the cutter as shown in Figs. 3194 and 3195, the former being a tongue cutter for cutting a groove, and the latter a grooved cutter for cutting a tongue.
Other examples for such cutters are given as follows:
Fig. 3196 represents a cove cutter and Fig. 3197 an ogee. Fig. 3198, a double beading, and Fig. 3199 a bevel cutter, and it is obvious that by a suitable arrangement and shape of groove cutting edges of any of the ordinary forms may be produced.
The advantages of such cutters are that the plain bevelled face or facet of the cutter may be ground (to sharpen the cutter) on an ordinary emery wheel or grindstone, and the shape of the cutting edge will remain unaltered, providing that the cutter is always held to the grinding wheel or stone at the same angle, so that the length of the bevel remains the same.
A common practice is when making the cutter to so regulate the depth of the grooves or recesses in its face that the cutting edge will be of the required shape when the length of the bevelled facet is equal to three times the thickness of the cutter.
The method of finding the shape of cutter necessary to produce a given shape of moulding has been fully explained on pages 80 to 85, Vol. II.
Various forms of side heads are shown in the figures from 3200, to 3207. Fig. 3200 is a two-sided plain head, or in other words two diametrally opposite sides of the head are provided with bolt holes, for cutter fastening bolts. Fig. 3201 represents a four-sided slotted head, each side having T grooves, so that the cutter may be adjusted endways on the head. This enables the use of four narrow cutters, thus taking the cut in detail as it were.
The two-sided head shown in Fig. 3202 is provided with a set screw, by means of which a delicate adjustment of the height of the cutter may be made. Fig. 3203 represents a three-sided slotted head, or in other words T-shaped grooves, and not bolt holes are used.
CUTTER HEADS WITH CIRCULAR CUTTERS.
This form of cutter head was invented by S. J. Shimer, and are generally known as Shimer cutter heads. The principle of construction is shown in Fig. 3204, which is for an ogee door pattern.
The cutters are circular in form and are seated at an angle to the flange to which they are bolted, this angle giving side clearance to the cutting edges.
The full amount of cut is taken in successive stages or increments; thus in the figure, the two upper cutters would produce one half the moulding, and the two lower ones the lower half. As the cutters are sharpened by grinding the front face, therefore they will maintain correct shape until they are worn out. Fig. 3205 represents a Shimer head for producing the tongue, and Fig. 3206 a similar head for producing the groove of matched boards.
Fig. 3207 shows the action of the groove head, the cutter or bit d being shown in full lines and the second cutter being shown in dotted lines. Cutter d, it will be seen, operates on one half of the groove, and cutter c on the other half, each cutter having side clearance, because of being seated on a seat whose plane is not at a right angle to the axis of revolution of the head.
By thus taking the cut in detail, the head works steadily, while the side clearance makes the cutters cut clean and clear.
JOINTING MACHINE.
“Jointing” a piece of wood or timber, means producing a surface, so that the joint between two pieces that are to come together or be glued shall be close. In order to produce surfaces that shall be true enough for this purpose, it is necessary that the work be held in such a way that it is not sprung or deflected by the holding devices or feeding apparatus.
Fig. 3208, for example, represents a jointing machine, in which the work abuts against an inclined plate p at one end, while the other end is clamped down to the table, which is traversed past the revolving head h, to which are secured two gouge-shaped cutting tools, one of which is seen at t. By using tools of this class, the amount of cutting edge in action is small, and will not therefore spring the work, and if the cutter spindle is adjusted to have no end motion, the work will be true, notwithstanding any slight vibration of the head, because its plane of revolution coincides with the plane of the surface being surfaced or jointed.
In some jointing machines, knives are set on the face of a revolving disc, an example of this class of machine being shown in Fig. 3209, which is for facing the spokes of wheels and for finishing the mitre joint on them.
Three cutters are used, each being set at an angle to a radial line, so that the inner edge of the knife will meet the work first. This gives the knives a shearing cut, and prevents the whole of the cutting edge from striking the work at once. The spokes are placed against a stop on the table, and brought into contact with the cutters by the foot treadle.
The table has beneath it a spiral spring at each end, which returns the table as soon as the foot pressure is released from the treadle. The cutter head or disc is 10 inches in diameter, and should make 2,000 revolutions per minute.
Stroke jointers are machines (such as shown in Fig. 3210) in which a long plane e of the ordinary hand plane type is worked along a slide by a connecting rod c, operated by a crank motion. A machine of this class will do very accurate work, but is obviously suitable for thin work only.
A machine constructed by J. J. Spilker, for cutting mitre joints by hand, is shown in Fig. 3211. The frame a carries a slideway for the slide to which the mitre cutting knife k is secured. The handle g operates a pinion gearing into a rack, which gives vertical motion to the slide and knife. At c is a fence or gauge against which the work is rested, and which is capable of a horizontal motion, so as to bring the work more or less under the knife. For heavy work, the fence c is set back, so that the first cut of the knife will leave the moulding, as shown at h, partly severed, and a second cut is necessary to sever it; for very fine work, a fine shaving may be taken off by a cut taken on the end of each piece separately, after the piece is severed. At d is a graduated scale or rule for cutting the work to exact dimensions, and as its lines are ruled parallel to the right hand edge of the knife k, the inside measurements of a mitre joint may be taken at the outer edge, and outside measurements at the inner end of each line, a set stop at e serving to gauge the pieces for length.
MOULDING OR FRIEZING MACHINES.
These are machines that cut mouldings on the edges of the work. The term friezing is applied by some, when the machine has but one cutter spindle, while by others these machines, whether having one or two spindles, are termed edge moulding machines. Still another term applied to this class of machine is that of variety moulders or variety moulding machines.
In machines of this class, it is of primary importance that lost motion or play in the bearings be avoided, because the cutter end of the spindle overhangs its bearings, and any side play of the spindle in its bearings is multiplied at the cutting edges of the cutters. Perfect lubrication of the spindle bearings, and ample bearing surface on the journals and bearings, are therefore of the first importance.
The work is rested on the upper surface of the table, and is fed to the cutters by hand.
Figs. 3212 to 3215 represent a machine by J. S. Graham. The frame b, b, Fig. 3213, of this machine is cast in one piece cored out, and the base is wide, so as to give necessary solidity. The hollow column is fitted with a door w, and shelves v, v, forming a very complete case for the reception of tools, cutters, etc. The spindle boxes and slides c are one casting. They are planed on centres and held in the frame b′, Fig. 3215, by large gibs l, and sliding surfaces shown in c′, Fig. 3214. They are adjustable vertically by hand wheels k, in front of frame in connection with nut o, as shown in Fig. 3214, and require no lock to hold them at the proper height.
The cap o′ (Fig. 3213) has an oil chamber j and wick which feeds the oil to the upper bearing. The lower box is fitted with a patent self-oiling and adjustable step shown at a, b, c. The cap a, upon which the spindle d rests, has a small opening in the centre. The circular block b, under it, also has a hole in the centre. The bolt d has two holes in it, one horizontal and the other vertical.
The chamber surrounding this step and cup is filled with oil. The motion of the spindle d on the cap a causes the oil to flow from the chamber through the openings to the spindle. Thus the oil is kept in constant circulation. The end of this spindle d is by this arrangement kept always lubricated.
The spindles d are of 17⁄8 hammered tool steel accurately turned and fitted in the boxes, which are of extra length, and lined with the best genuine Babbitt metal. They are 30′′ from centre to centre, and have independent screw tops, as shown at s, enabling the operator to use various sizes for large or small work, or clear the table of either spindle for special work.
h is the threaded part of the screw top, g is the nut, and f the fill-up collars.
The iron table a, a is 5 feet by 4 feet, planed and fitted with concentric rings e, e around the spindle, to suit the various sizes of heads and cutters. A heavy wooden table, made of narrow glued-up strips of hard wood, can be used if preferred.
This machine has been run up to 6,000 revolutions per minute, without perceptible jar, and cutter heads as large as 8′′ diameter may be used on it for heavy work.
Fig. 3216 represents an edge moulding machine by J. H. Blaisdell. In this machine the table is raised or lowered by the hand wheel upon the central column. The construction of the spindle and its bearings is shown in the sectional view, which also shows the square threaded screw by means of which the table is raised. The spindle has a coned hole for receiving the cutter sockets, which are therefore readily removable.
Figs. 3217 to 3220 represent examples of the shapes of cutters for use on edge moulding or friezing machines. Fig. 3217 represents a cutter for bevelling the edge of the work, the cutting edges being at a, b, or at c, d, according to the direction in which the cutter is revolved.
Fig. 3218 represents an ogee cutter, in position on the cutter spindle. As these cutters are made solid and accurately turned in the lathe, they are balanced so long as the cutting edges are kept diametrally opposite. The front faces only being ground to sharpen the cutting edges, the cutter always produces work of the same shape.
Fig. 3219 represents a cutter (in a chuck) for cutting a dove-tailed groove, and Fig. 3220 one for rounding an edge, it being obvious that a wide range of shapes may be given to such cutters, and that, as they may be sharpened on an emery wheel, they may be left comparatively hard, thus enhancing their durability.
To regulate the depth to which a cutter such as shown in Fig. 3220 will cut, a collar or washer is placed beneath it to act as a guide to the edge of the work.
Fig. 3221 represents a machine in which rotary cutters are used to produce all kinds of panel work, as well as edge moulding or friezing. In this case the cutter is above the table, the latter being adjustable for height to suit the thickness of the work. Examples of some of the work are shown at the foot of the machine.
WOOD BORING MACHINES.
The rapidity with which holes may be bored in wood enables the feed to be most expeditiously performed by hand or by foot motion. A foot motion leaves both the workman’s hands free to adjust and change the work, and is therefore suitable for light work or work having holes of a moderate depth.
The work tables of wood boring machines are provided with suitable fences for adjusting the work in position, and in some cases with stops to adjust the depth of hole.
Any of the augers or bits that are used in boring by hand may be used in a boring machine, but it is obvious that, as the bit or auger is forced to its feed by hand or foot, and as its revolution is very rapid, the screw point, which is intended as an aid in feeding when the bit is used by hand, is not necessary. On this account most augers for use in machines are provided with triangular points instead of screw points.
In Fig. 3222 is shown a wood boring machine by J. A. Fay & Co. The table is gibbed to a vertical slide on the face of the column, and is adjustable for height by the hand wheel a, which, through the medium of its shaft and a pair of bevel gears, operates the elevating screw b. The spindle c feeds through its bearings, the supporting rod d being pivoted at its lower end to permit c to feed in a straight line vertically. The feeding is done by the treadle f, which operates the rod e.
The table may be set at an angle of 30 degrees from the horizontal position.
The weight w counterbalances the treadle and brings it to its highest position when the workman’s foot pressure is removed.
The holes may all be gauged to an equal depth (when they are not to pass through the work) by so adjusting the height of the table that the hole is of the required depth when the treadle is depressed to its lowest point, or limit.