Part 12 (2/2)
[Illustration: Fig 7 Turret Lathe Tool Equip Flywheels]
The periphery of the rim is now finished by cutter _l_ in the turret toolpost which is indexed to the proper position for this operation The rear face of the ri was done Tool _e_ is then removed and replaced with _d_ which rounds the inner corner of the ri the outer corner of the rear side For finishi+ng the front faces of the ri head, identical with the first one, is employed This is shown in position in the illustration Cutters _f_{1}_, _g_{1}_ and _h_{1}_ correspond with the cutters _f_, _g_ and _h_, previously referred to, and perfor operation of finishi+ng the back of the hub is effected by cutter _p_ This cutter is reh the bore; the cutter is then replaced in its slot and the rear end of the hub is faced by feeding the carriage away from the headstock
This co finished at one setting
=Finishi+ng a Webbed Flywheel in Two Settings=--The plan views _B_ and _C_, Fig 7, show the arrange a webbed flywheel which has to be machined all over This, of course, requires two operations In the first of these (see sketch _B_) the rough casting is chucked on the inside of the riular inside hard chuck jaws _b_ The cored hole is first rough bored with cutter _n_ attached to the end of boring-bar _e Next, the boring-bar _ back out of the way This bar is steadied by its bearing in bushi+ng _r_ in the chuck Two cutters, _n_{1}_ and _n_{2}_, are used to roughly shape the hole to the desired taper, the s finished to within 0002 inch of the required dia with the bar _ by the tool _k_ in the turret toolpost The latter is then shi+fted to bring the tool _j_ into position for re the scale on the periphery of the wheel Next, the hole is reamed with taper rea _r_
The first of the facing heads is now brought into action This facing head carries a guide _t_ which is steadied in a taper bushi+ng _c_, driven into the taper hole of the hub for that purpose The top cutter _f_ turns the periphery, cutter _g_ turns the hub and faces the web, and cutter _h_ faces the rim A fourth cutter _e_ on the under side of the head faces the hub This casting is now , si_{1}_ and _h_{1}_, in the other facing head are used, the latter being supported by the taper bushi+ng _c_ in the sa Tool _l_ in the carriage turret is used to round the outer and inner corners of the ri
In the second cycle of operations, shown at _C_, the casting is chucked on the outside with the soft jaws _b_, which are bored to the exact diameter of the finished ri bushi+ng _c_, which is tapered to fit the finished hole in the hub, and has an accurate bearing in bushi+ng _r_ in the chuck This bushi+ng is provided with a threaded collar for forcing it into the work and withdrawing it The scale on the web and the inside and face of the rim is first broken with the tool _k_ in the turret toolpost These surfaces are then roughed off with cutters _f_, _g_ and _h_, in the facing head This latter is steadied by a pilot _t_ which enters the hole in the sliding bushi+ng _c_ on which the work is supported A light cut is next taken with cutters _f_{1}_, _g_{1}_ and _h_{1}_, in the finishi+ng facing head, which completes the operation
=Tools for Turret Lathes=--The operation of a turret lathe after the tools have been properly arranged is not particularly difficult, but designing and ive thethe tools on the machine, requires both skill and experience For some classes of work, especially if of a rather coned, although there are certain standard types used on turret lathes which are adapted to general turning operations
So
=Box-tools=--Tools of this type are used for turning bar stock There are s 8, 9 and 10 Box-tools are held in the turret and they have back-rests opposite the turning tools, for supporting the part being turned The box-tool shown at _A_, Fig 8, is for roughing The cutter _a_ is a piece of high-speed steel beveled on the cutting end to produce a keen edge It takes a shearing tangent cut on top of the bar and the latter is kept fro away by means of the adjustable, hardened tool-steel back-rest _b_ This tool is considered superior to a hollow mill whenever a fair amount of stock must be removed If considerable s box-tool shown at _B_ should follow the roughing box tool, but in most cases, especially if the part is to be threaded by a die, a finishi+ng cut is unnecessary
[Illustration: Fig 8 Different Types of Box-tools for Turret Lathe]
The finishi+ng box-tool _B_ is also used to follow a hollow mill if special accuracy or sht finishi+ng cuts, the allowances varying from 0005 inch to 0015 inch in diameter The cutters are round and set to take a scraping end cut This particular tool has two tool-holders which perer number of sizes must be turned, extra tool-holders can be applied
The single-cutter box-tool shown at _C_ is bolted directly to the face of the turret instead of being held by a shank in the turret hole, and it is adapted for heavy cuts such as are necessary when turning coe bar stock The tool-holder _a_ swivels on a stud, thus allowing the cutter to be withdrawn fro the turned surface The high-speed steel cutter is ground to take a side cut on the end of the bar The latter is supported by hardened and ground tool-steel rolls _b_ which revolve on hardened and ground studs These rolls arearms which have a screw adjustment for different diameters
They can also be adjusted parallel to the bar, thus enabling them to be set either in advance of or back of the cutter The opening in the base allows the stock to pass into the turret when it is not larger than the turret hole
The box-tool shown at _D_ is similar to the one just described, except that it has two ordifferent diaround to take a side cut Ordinarily this gives a satisfactory finish, but if special accuracy and shing and one for finishi+ng, the latter being ground to take a light scraping end cut
The taper-turning box-tool shown at _E_ is designed for accurately turning tapers on brass or cast-iron parts, when there is a small amount of stock to be removed The taper is obtained by cross motion imparted to the cutter slide as the turret advances The taper-turning box-tool shown at _F_, instead of having a single-point cutter, is provided with a wide cutter _a_ This tool is designed to turn tapering parts of s the use of a support which cannot be provided with a straight for tool and holder mounted on the cut-off slide The cutter is backed up by the screws shohich also provide adjuste The bar is supported by the three back-rests shohich also have screw adjust=--Box-tools are not only used for cylindrical and taper turning on the end of a bar, but for s 9 and 10 show a nuns, with examples of the work for which each is intended While these tools are designed for soht modifications be adapted to other work
[Illustration: Fig 9 Box-tools and Work for which they are Intended]
A box-tool of the pilot type that is used for finishi+ng, after the surplus stock has been re
9 The work, which is the cone for a ball bearing, is shown at _a_ by the dotted lines and also by the detail view to the right The pilot _b_ enters the work before either of the cutters begins to operate on its respective surface The inverted cutter _c_, which sizes the flange of the cone, is held in position by a clamp _d_, which is forced down by a collar-head screw The cutter is further secured against a beveled shoulder at _g_ by the set-screws _f_, and it is adjusted forward by the screw _e_ By loosening the screws _f_ and the collar-head screw, the cutterThe cutter _h_ is adjusted to cut to the proper diameter, by the screws _l_, after which the clamp _k_ is made level by the screw _j_ The collar-screw _m_ is then used to secure the tool in place The cutter is htly cupped out on the cutting end to give keenness to the cutting edge The adjusting screw _o_, which passes through plate _p_, prevents the cutter fro screw plate has its screw holes slotted to avoid re the screhen it beco Pilot _b_ is held firh the shank makes it easy to remove the pilot, in case this is necessary
A pilot box-tool for finishi+ng another type of ball bearing cone is shown at _B_ The shape of the work itself is indicated by the dotted lines _a_ and by the detail view This tool is somewhat similar in its construction to the one just described The cutters _b_ and _c_ are inverted and are used to face the flange at _d_ and to turn it to the proper dia_ and are adjusted forward by the screw _h_ The cutter _j_, which operates on top of the stock, rests on a bolster, of the proper angle and is adjusted up or down by the screws _k_ The claainst this tool, is beveled to correspond with the angle of the tool
This clamp is secured by the collar-scren and it is leveled by set-screws _s_ The adjusting screw _p_ prevents the cutter fro-screw plate are also slotted in this case so that it will not be necessary to remove any screhen the cutter has to be taken out of the holder
A box-tool for finishi+ng a treadle-rod cone for a sewing machine is shown at _C_ This tool is also of the pilot type The cutters in it operate on opposite sides of the cone _a_ The inverted cutter _b_ sizes the cylindrical part of the cone, while the front cutter _d_ is set at the proper angle to finish the tapered part The rear cutter _b_ is held in place by the cla_ and a collar screw It is adjusted forward by the screw _h_ in the plate _i_ which is held by screws as shown The pilot is retained by a set-screw, and it is easily re a sh the shank The cutter _d_ is held by clah a tapped hole in plate _o_ The screw holes in both the adjusting plates _i_ and _o_ are slotted to facilitate their re 10, is used for finishi+ng the bushi+ng of a double-taper cone bearing _a_ The cutters are so arranged that they all cut on the center; that is, the cutting edges lie in a horizontal plane The inverted cutter _b_ at the rear forular surface, and the cutter _c_ in front fore diameter is turned, to size by cutter _d_ The pilot _e_ has a bearing in the bore nearly equal to the length of the work and it is provided with oil grooves, as shown The taper shank of this pilot is tapped for the screw _i_ which extends the whole length of the shank and is used to draw the pilot back to its seat It is not necessary to re-screw plate _k_ to take out the cutter _b_, as the latter can be drawn out from the front after the collar-screw _ off the adjusting-screw plate _s_ after loosening the collar-screw _n_ The cutter _d_ is held in a dove-tailed slot by two headless set-screws _q_
It is also backed up by an adjusting screw in the plate _s_ These adjusting screws should all have fine threads, say from 32 to 40 per inch, and be nicely fitted so they will not loosen after being adjusted
The box-tools shown at _B_ and _C_, Fig 10, are for turning the sides of a loose pulley for a sewing machine This pulley (shown by the dotted lines) is finished in two operations The box-tool for finishi+ng the side of the pulley on which the hub projects beyond the rim, is shown at _B_ The inverted cutter _a_, which faces the end of the hub, is held by a clamp _c_ (clearly shown in the end view) from the under side and it has no adjustment The collar-screw _d_ is tapped into this cla out of place by the dowel-pin _f_ The pilot _g_ is made small in the shank, so that tool _a_ can be so placed as to insure the removal of all burrs around the bore of the hub The pilot is held by a set-screw and it is provided with oil grooves The cutter _j_ sizes the outside of the hub, and the cutter _k_ faces the side of the pulley rim These cutters are both held by the clamp _l_ and the collar-screw _m_ No side plates are used on this tool, and the cutters are all easily removed