Taylor Hobson Engraver Manual

Section I

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This information is from a copy of the manual, from my perspective its a copy of a copy etc....because the images are quite bad, they are however readable.

There are no chapters so it will be in three sections

MODELS C - CB - CX - CXL

 

ENGRAVING

MACHINES

 

ASSEMBLY AND

OPERATING

INSTRUCTIONS

 

Including Instructions for use of "Javelin"

Electric Etcher on Engraving Machine and

Resistance Etcher.

 

 

PLEASE HAND TO

THE OPERATOR

Price three shillings and sixpence

 

 

TAYLOR, TAYLOR & HOBSON, LTD

Head office and works : STOUGHTON STREET, LEICESTER, ENGLAND

Telephone : Leicester 20135 Telegrams : "Lenses, Leicester.

page 1

 

Standard Equipment

supplies with Taylor-Hobson Engraving Machines

 

Whenever possible machines are dispatched with working accessories, etc., as detailed below. We cannot guarantee that all accessories specified will be supplied with every machine, but no machine will be sent out minus any accessory likely to impose restrictions on its usefulness or prohibit its being employed in a proper manner.

 

Equipment supplied with "C" and "CB" Models

___Code___

1
Magnifier for examining cutter points. 110/15
2
Oilstone for finishing cutters after grinding. 110/19
3
Style collar for use when regrinding the style. K025
4
Pair of work clamps with screws and nuts for holding work on the table. 110/12
5
Table fence for squaring up work and work fixtures 110/11
6
Pantograph slider wrench. Also fits style jacket and work clamps 110/122
7
Cutter wrench for inserting and extracting cutters 110/120
8
3 inch/24 wrench for the table and saddle locking screws. Also fits the cutter fame link centres. 110/121
9
1/2-inch box wrench (or alternative, according to bolt head used) for the head and copyholder bolts and cutter grinding arm. 110/124
10
Wooden Plug for cleaning the cutter spindle and cutter grinding sockets. 110/253
11
Box of sample cutters 110/159
12
Instruction book
---------

Equipment supplied with "CX" and "CXL" Models

as above

-----
Endless driving belt 110/217

Cutter Grinding Equipment

Supplied as an extra and particulars are given in separate literature

available upon request.

page 2

 

General Description

 

"C" - "CB" - "CX" and "CXL" Models

The chief features of the "C," "CB," "CX" and "CXL" machines are shown in Fig.1. A copy of the engraving desired is arranged in the copyholder (K) and the article to be engraved is held upon the work-table of the slide-rest (S) beneath the cutter (N). The slide-rest has both horizontal and vertical movements. The cutter, rotated at a high speed by the driving band (Q), is lowered into the work or lifted from it by the operator, who controls the feed screw (32) with the left hand, while the right hand guides the pointed style (G) along the lines of the copy. This action moves the cutter, which produces the desired engraving. The style (G) is connected to the cutter by means of the pantograph whose sliders (H) and (E) can be set along their graduated bars so that the engraving may be varied in size. Models "C" and "CB" have pantographs reproducing at one-third (1:3) to one-sixteenth (1:16) the copy size - smaller reproductions with special. Models "CX" and "CXL" have, normally, pantographs reproducing between one-half (1:2) and one-sixteenth (1:16) the copy size - smaller reproductions with special settings. These latter models can be furnished with an alternative pantograph copying at full size (1:1) and reproducing down to one-sixth (1:6) the copy size. The cutter spindle, feed mechanism, pantograph, cutter frame, frame link, head and copyholders are similar on all models but differ somewhat in detail as described later.

It is desirable that a skilled mechanic should be responsible at first for all adjustments and for teaching the operator how to run the machine.

 

Position of Machine

The best position for the machine is in front of a good window, the operator facing the light. Electric light should be provided to illuminate the work when required and be placed behind and slightly above the cutter, shaded so that it does not shine directly in the operator's eyes.

Comfort of Operator

 

The operator should be seated on a stool about 2 feet high with the copyholder on the right. A convenient foot rest is attached to the machine pedestal, except "CXL."

Supply of Line Copy

 

An adequate supply of Standard Line Copy should be provided for the required work, with an assortment of suitable cutters. The workpan is provided to hold cutters and tools in an orderly manner.

 

The importance of correctly ground cutters

Separate literature is obtainable on Taylor-Hobson Cutter Grinders, for the purpose of ensuring perfect engraving through the use of correctly ground cutters (see note on page 17).

page 3

 

Erecting Models C and CB

 

Every machine is completely erected in our works, thoroughly tested my skilled inspectors, and certified within close limits of error. To facilitate transit, the pedestal, frame, head, copyholder and pantograph may be packed separately.

Erect models "C" and "CB" as follows after referring to Fig.1 :-

(1) Place the pedestal on its side and insert the end of the foot rest through the hole in the side, screwing up the nut from the inside.

(2) Locate pedestal in required position and with the straight edge of the top flange to the operators left.

(3) Get the workpan bolt 5/8 x 3.1/4 ready to put in the hole opposite the straight edge of flange, place the machine on the pedestal with flanges in line and at once secure with this bolt through into work-pan. Insert the other bolts from below and screw home all three nuts.

Then refer to Fig.2 and proceed thus:-

(4) Put the head (P) in place on the frame and clamp it with bolt (M) at the reduction marked 3 on the scale (R)

The bolt (M) screws into the head dog on the under side. Note that this head dog has one straight and one beveled edge. The frame is shaped inside to match and the head dog fits only one way. The bolt must not be over tightened or the dog will break. It is so designed, rather than risk the splitting of the frame.

(5) Remove the bevel bar (F) from the pantograph - it simply drops free - and slip it into the slider (H), the graduations on the bar and the clamp bolt on the slider both being to the front. Set the

bar with the line marked 3 against the bevel edge of slider, and clamp by means of the hexagon head screw.

(6) Assemble the pantograph, holding it by the long arm (L) and fitting holes in the bevel-bar (B) and the link (J) over the pins in bar (F). Do not allow the whole weight of pantograph mechanism to hang on the ball-bearing in slider (H) or this may be damaged.

(7) Swing the pantograph round and insert the bar (B) in the slider (E) at its beveled end . Set the bar with the line marked 3 against the bevel edge of slider, and clamp by means of hexagon head screw.

(8) Clamp the copyholder (K) on to the head (P) by means of the bolt provided. The pantograph is now set for operation at 1:3 reduction.

If the floor is uneven, the base of the pedestal should be packed up so that the machine is rigid and level, otherwise the pantograph is apt to move itself. It is seldom necessary to fix the machine to the floor.

page 4

 

Compact Drive

For "C" and "CB" Models

This type of motor drive is fitted to most machines making them fully self-contained. It can be fitted easily to machines at present driven by other means, full instructions being supplied to users desirous of carrying out fitting in their own works.

The motor drive is dispatched complete with belts on a Compact Drive fitted to a "C" machine. The arrangement is similar for a "CB" machine, but the motor belt drives a pulley at D via a pair of jockey pulleys. Pulley D and the jockey pulleys are carried on a separate bracket which is attached to the lug on the side of the machine frame. This slight variation is imposed by the difference in the shape and dimensions of the frames of the two machines.

Fig.3 shows the type M2 Compact Drive fitted to a "C" machine. The Compact Drive for the "CB" machine is known as the type M3. The cutter spindle speeds obtainable with this form of drive and with the current design of ball-bearing spindle range between 3,000 rpm and 15,000 rpm

The motors fitted to the Compact Drive are not of the Universal type and are suitable only for the electric supply for which they are ordered.

By adjustment of the belt between the driving pulley (D) and the cutter spindle, any one of four spindle speeds can be obtained. The belt between the driving pulley (D) and the motor pulley (M) remains fixed in the position shown.

The following are the four combinations available and the speed obtained from each :-

Large step on pulley (D) to small step on spindle pulley.....15,000 rpm.

Large step on pulley (D) to large step on spindle pulley.....8,750 rpm.

Small step on pulley (D) to small step on spindle pulley.....5,120 rpm.

Small step on pulley (D) to large step on spindle pulley.....3,000 rpm.

Adjustment for stretch in belts is provided by means of a stay rod to the cutter spindle and a slotted link which permits adjustment of the driving pulley.

NOTE particularly the following codes for ordering spare belts :-

Spindle belt for "C" and "CB" models coloured green and white code 110/279

Motor belt for "C" model coloured white code 110/276

Motor belt for "CB" model coloured white code 110/399

Motors

These have grease packed bearings which need filling occasionally with any good quality grease. Do not flood the bearings with oil.

Special Note

All machines of the "C" and "CB" pattern, sold approximately from March, 1949 onwards, will have a different design of motor frame, which in some cases has necessitated the provision of a special belt. The code number will be indicated on a label attached to the drive, and it is most important when ordering replacement motor drive belts, that this number be quoted for the motor drive.

page 5

 

Erecting Models "CX" & "CXL"

The erecting of "CX" and "CXL" models is simplified as the machines are shipped attached to the pedestals. The fitting of the head, pantograph and copyholder is carried out exactly as for models "C" and "CB."

The drive is by a 1/4-hp motor attached to the pedestal and running at 2,850 rpm The motor is assembled at the works and connected to the switch on the brake rod. The earth wire should be connected to a water pipe or some suitable "earth" to conform to Board of Trade regulations. If fitted with 3-phase motor, its three wires are all to be connected to the supply. Customer should "earth" the machine separately. The correct direction of rotation is given by an arrow engraved on the spindle pulley. The belt is fitted as shown in Fig.4 for the cutter spindle to revolve clockwise when viewed from above. The same speed range as given for the Compact Drive is available. Fig.4 shows how the guide pulleys are fitted on the vertical tube from the motor bracket, also the correct position of the spring loaded stay rod. This stay rod is packed separately and should be attached to the yoke around the cutter spindle by means of the small pin provided and the split pin put in place. It is important to see that the spherical ended collar on the stay rod locates in the notches on the guide pulley bracket.

It is important to see that the spherical ended collar on the stay rod locates in the notches on the guide pulley bracket. It will be noticed that these guide pulleys swivel about for a choice of two positions, one for driving the cutter spindle and one for driving the grinding attachment.

See separate instructions on cutter grinding with models "CX" and "CXL" models.

The brake rod is pushed away from the column after switching off, to stop the motor instantly.

Order spare belts by code No. 110/217

The Ball-Bearing Spindle (patent)

Taylor-Hobson Engraving Machines are fitted with ball bearing cutter spindles of unique construction, Fig.5. The inner ball races are formed in the spindle itself in order that it may run "dead true." The design eliminates radial and end shake. The spindle never requires adjustment.

The quill is provided in the first instance with a suitable lubricant and sealed at one end by a cap and at the other end by the pulley, so that no dirt can enter the bearings. This method of lubrication ensures considerable use without attention and it is recommended that no change be made without our advice. These spindles may run up to 15,000 rpm without distress and are valuable not only in engraving

machinery, but for numberless special operations in workshops generally. The spindle has a truly concentric hole for cutters and its two-step pulley is grooved for the endless fabric belts referred to in previous pages.

When desired, usually on heavy work or engraving with a parallel sided cutter, cutters can be locked in the spindle with a cutter retainer (B) and cap (C) which screws on to the spindle nose (A).

The cutter is inserted firmly with the cutter wrench in the ordinary way before fitting the retainer and the cap. The cap should then be given one or two preliminary tightening's before the final one to ensure that the retainer locates correctly.

Order spare cutter retainers by code No. 110/261

page 6

 

Adjustment and Operating

Adjustment for Wear in Cutter Frame

Wear between the spindle and the cutter frame can be taken up by the hexagon-headed screw in the split sleeve of the cutter frame. This screw should be tightened no more than is necessary

just to hold the weight of the spindle. Over-tightening will put undue strain on the feed mechanism. Do not clamp too tightly the feed yoke over the spindle as this may distort the spindle.

The Pantograph

The pantograph and sliders must be kept clean and all pin bearings should occasionally be oiled. The three ball-bearing joints will work for long periods without developing any play, but they may be adjusted by tightening their nuts slightly. Such adjustment should only be made when the pantograph has been removed so that the play in each individual joint may be felt and the nut tightened only so far as is necessary just to remove play. If tightened too much the ball races may be damaged.

To remove the Pantograph

Refer to Fig.2 then :-

(1) Holding the pantograph arm (L) withdraw the bevel bar (B) from the slider (E) and without releasing the arm (L), lift it, together with bars (B) and (J), away from the loose bar (F).

(2) Withdraw the bar (F) from the slider (H).

The pantograph ( see Figs. 1 and 2) controls the horizontal movement of the cutter, causing it to reproduce faithfully, on a reduced scale, the movement of the style. Reductions from 1:3 to 1:16 are marked on the "C" and "CB" pantographs and from 1:2 to 1:16 on the "CX" and "CXL" pantographs.

To avoid confusion, only the reductions commonly used are marked on the bars. To set for other reductions reference should be made to the schedules on pages 26-28.

To set for a required Reduction

(1) Slacken the hexagon-headed screws which clamp the sliders (H) and (E), Fig.1 ; adjust the sliders to bring their index edges exactly against the near edge of the required graduations on the bevel bars and clamp in these positions. This must be done accurately or the engraving will be distorted.

(2) Slacken the bolt (M), set the head

(P) with the required graduation on its scale opposite the index on the frame, and clamp in position.

For reductions not marked on the pantograph it will generally suffice to set the head to the nearest reduction marked at (R).

To set the Style

Slacken the clamp screw, hold down the style (G), Fig.1, with its point in the copy, raise the pantograph end 1/16-inch (not more) and reclamp. The slight "set" of the pantograph arm thus produced will help to keep the style in the copy, and the pantograph will spring sufficiently to permit the style to be moved from one character to another.

Area covered by Style and Cutter

The area which can be covered by the cutter varies directly with the scale of reduction but the are covered by the style is not greatly affected by changes of the pantograph setting.

The standard copyholders represent generally the largest rectangular figures which can be covered by the style, but it can reach an irregular figure somewhat larger. In rare cases in which this larger area is useful copies may be held on either the No.0 copyholder or on a board 1 inch thick and 17 inches by 8 inches attached to the head in place of the standard copyholder. For this purpose the head is drilled for three No.12 wood screws.

Figs.36 and 37 (see end of book) show the largest areas which can be covered by the cutter with the various reductions.

Reductions less than 1:2

Engraving with reductions less than this is not usually desirable because of lack of leverage to control the cutter movement, but it is sometimes necessary, as in duplicating and making copy.

Equal Pantographs (supplied as an extra)
The "CX" and "CXL" models can be fitted with pantographs operating at ratios between 1:1 and 1:6. These pantographs are complete with their own special heads and utilise standard copyholders. Areas covered are slightly larger than diagrams in Figs. 36 and 37. Schedule of intermediate reductions is on page 28.

page 7

 

Adjustment and Operating

The Cutter Feed Mechanism

The depth of cut may be regulated in two ways :-

Method 1

By eye. This will, as a rule be found quite satisfactory for shallow engraving.

Method 2

By means of the adjustable stop (33). This method is effective for deeper cuts, and where the surface of the work is sufficiently level it will ensure uniform depth of cut.

Lower the cutter until the yoke (30) is against the locked stop (33). With the machine running, raise the work-table by means of vertical screw until the cutter penetrates to the required depth. Withdraw the cutter by means of the feed wheel (32). The cutter is now lowered into cut be means of the feed wheel, and the same depth of cut attained. If it is desirable to engrave by this method to a known depth, say, 0.015 inch, a 0.015 inch feeler gauge is placed on the stop (33), and the cutter fed down until the feeler gauge is trapped between the locked stop and the yoke while the cutter is clear of the work. The work-table is then raised by means of its vertical screw till the cutter just touches the surface of the work. The cutter may now be made to penetrate the desired depth by with-drawing the feeler gauge and feeding the cutter down until interrupted by the stop.

The Cutter Frame and Link

The cutter frame should be so suspended on its centres that the flange on the lower race of the ball-bearing in slider (H), Fig.1, fits against the top facing on the cutter frame without straining straining the pantograph either up or down.

To Adjust

(1) Remove the pantograph so that the centres can be examined by themselves.

(2) If a joint is loose slacken the nut on the outside of one of the centres and tighten the nut on the inside to draw the centre through its hole.

The centres should be so adjusted that a very slight stiffness can be felt when the links are moved by hand. Both nuts must be left tight. In making this adjustment the height of the cutter frame must be kept as originally set. If it is raised at all the pantograph will not have sufficient room to operate properly.

 

Shake in the spindle, pantograph joints or cutter frame cantres, is generally indicated by bending of the ends of engraved lines as shown in Fig.9, page 13.

The Work-table and Slide Screws

The screws which actuate the work-table and sliderest are held in place by slit screwed bushes each provided with two holes, one on either side of the slit. Each slide screw has a corresponding hole.

To Remove a Slide Screw or take up end shake

Insert a 1/8-inch diameter steel rod

through the bush hole to your right of the slit and into the hole in the screw ; the two parts will be locked together and may be unscrewed as one by turning the handle. Be careful to choose the correct hole in the bush so that it tends to close when the screw is turned, otherwise the bush cannot be moved.

When replacing the screw, the other hole in the bush must be used.

The Work-table

The work-table can be raised, lowered, traversed forwards, backwards, and to right and left by means of three crank handles. When the machine is set up for repitition work, clamp the slides so that the table cannot be accidently disturbed. This is done by means of the long screw underneath the table inside the bracket, and the bolt at the back off the vertical slide.

page 8

 

Copy Section

Standard Line Copies

Engraving 50% larger than the above can be produced on "CX" and "CXL" machines

with Pantographs operating at 1:2 reduction.

NOTE :- The above image is NOT actual size, click the image for a full size one, and one that will print at correct perspective.

page 9

 

 

Copy Section

COPY is used on the Engraving Machine to determine the path of the pantograph style and the cutter.

Generally, the most useful copy is a metal plate engraved with a V channel or track adapted to fit a style with a 90 degree conical point which the operator moves along the track. When the style is maintained with a good outline on its point, such copies last for a long time ; and the angular section prevents lateral slackness even though the copy be worn.

Line Copy Fig.7 (1)

Sunk Copy Fig.7 (2)

Raised Copy Fig.7 (3)

 

Line Copy - Fig.7 (1)

In Line Engraving, a pointed style is used, matching with a Vee-groove forming the outline of the character. With such copy, the width of line on the letter being engraved can only be varied by changing the size of the cutter, or by

using what is known as multiple Line Copy, where thick and thin lines appear in the same letter. In multiple Line Copy, the space between the lines must be such that in using a certain reduction, with a certain size of cutter, the metal between the lines is cleared away.

Sunk Copy - Fig.7 (2)

Sunk Copy is basically of the same form shown, but can have varying widths of line, such as may be required for Roman, Old English, Script, etc.

Raised Copy - Fig.7 (3)

This Copy is basically of the form shown, but here again the width of line or face may be varied to produce counterparts of the copy referred to under the heading "Sunk Copy" - taht is, Roman, Old English, Script, etc.

Copy of this kind of course necessitates clearing away surplus metal around each of the characters , and for this reason, therefore, some consideration must be given to this particular point when considering the engraving of letters say on a circle without complete set copy.

For instance, if a Post Office Stamp is to be engraved letter by letter, then it must be realised that metal must be left on which to engrave the next letter. Quite often certain letters are very close together, so close in fact that they do not permit that passage of a cutter right through, and if the work is of this character, then it is generally considered desirable to make one complete "Set" Copy, consisting of all the characters mounted on one piece of metal in the correct relation to one another.

Styles or Tracers

In Fig.7 (1), a 90 degree conical style is used, which nominally fits the groove of the copy.

In Fig.7 (2) and (3), a flat-ended style is used, which wants to be as large as possible consistent with its ability to pass through the smaller apertures in the Copy where they are varying widths, such as Roman, Old English, and Script, etc. Where the reduction is small, and the copy is small, it is possible that just the flat-ended style will suffice, but where the copy is large, it may be found necessary to use "rollers," which my not pass through all the spaces

page 10

 

Section-II