Mechanick exercises: or the doctrine of handy-works. Applied to the arts of smithing joinery carpentry turning bricklayery. To which is added Mechanick dyalling: ... The third edition. By Joseph Moxon, ...

MECHANICK EXERCISES: OR, The Doctrine of Handy-Works.

Applied to the ART of TURNING.

§ XV. Of Turning Hard Wood, and Ivory.

IF the Wood be very hard, as Ebony, Lignum Vitae; or if it be Ivory, Bone, or Horn they are to Turn; they neither use the same Tools they do for soft Wood; because their edge is to tender: Nor do they use their other Tools as they do soft Wood. For the Tools made for Hard Wood are made with a stronger Point, Edge, &c. than they are for soft, as was said in Turning § 5. And they use them differently, because for Turning Soft Wood, they hold the Edge of the Gouge and Flat Chis|sel, at some considerable Distance from the Rest, mounting the Edge at such an Angle as will best cut off from the Work, as a great Chip as they can, or desire. And as they Turn the Work smaller, they guide the Chissel to follow the Work: But for Hard Wood, they raise the Rest near the Horizontal Plain of the Axis of the Work, setting it as close as conveniently they can to their Work, and lay their Tool flat and

steddy upon the Rest; which being hard held in this position, does by the comming about of the Work, cut or tear off all the Extuberances the Tool touches in the sweep of the Work. So that (as I said before) as in Turning soft Wood the Tool does somewhat follow the Work; in Turning hard Wood the Work comes to the Tool: And therefore you may perceive a great reason they have to keep the Tool steddy: For should it in one sweep of the Work be thrust nearer the Axis in any place, it would there take off more than it should.

Having prepared the Work fit for the Lathe, either with Hewing, or as some Hard Woods and Ivory may require, with Rasping, they pitch it between the Pikes, as before has been shewn, or such Work as it may be, as Boxes, and generally all Hollow Work, they fit into Collers, either by screwing the Mandrel on an Iron Axis; or fitting it with some other of the Mandrels described in Turning § 6. as is proper for it: As sometimes they fit the Work tight in|to an Hollow Mandrel, and the tight fitting in holds it whilst it is working upon: And some|times, if the Work be very thin, they fix it on a Flat Mandrel with Cement; But they are al|ways either to chuse one of the Mandrels descri|bed already in Turning § 6. or else contrive (as they often do) some other Mandrel conve|nient to the opportunity that accidentally their Business may require. For the Work (whether it be pitcht on the Pikes, or fitted into Hollow Mandrels, or otherwise) must run very steddy and tight.

But having thus fitted it into the Lathe, they begin to work with the Sharp-pointed Grooving Tool, or else with the Triangular Groowing Tool,

[figure]

and with the point of either of these Tools break the Grain of the Wood, by laying small Grooves upon its Surface, till they have pretty well wrought away Extuberances, and brought the Work tollerably near an intended shape, by streightning, hollowing, and leaving Risings in their several proper places.

Afterwards with edg'd Grooving Tools of a pro|per Breadth, they cut down and smoothen away the Extuberances left by the Sharp-pointed Groo|ving Tool, or the Triangular Grooving Tool, and bring the Work into a perfect shape. Which done, they smoothen the work with the Edge of a piece of a Blade of a broken Knife, basil'd a|way, by following the Work with it: That is, holding the basil'd Edge of the Knife close against the Work while it comes about: For then its sharp Edge scrapes or shaves off the little rough|ness the grosser Tools left upon the Work.

Lastly, they hold either a piece of Seal-skin or Dutch Reeds (whose outer Skin or Filme somewhat finely cuts) pretty hard against the Work, and so make it smooth enough to polish.

Hard Wood they polish with Bees-wax, viz. by holding Bees-wax against it, till it have suffi|ciently toucht it all over; and press it hard in|to it by holding hard the edge of a Flat piece of hard Wood made sizable and suitable to the Work they work upon, as the Work is going a|bout. Then they set a Gloss on it with a very dry Woollen Rag, lightly smear'd with Sallad Oyl.

But Ivory they polish with Chalk and Water, and afterwards dry it with a Woollen Rag, and a light touch of Sallad Oyl; which at last they rub off again with a dry Woollen Rag, and so set a Gloss on it.

If there be a Screw to be made upon the thin Edge of an Ivory, or Hard Wood, or Brass Box, they use the Screw-Mandrel, and its Socket, de|scribed in Turning 6. ¶ 4. and 5. as is shewn at the latter end of that Section.

§ XVI. Of Turning long and slender Work of Ivory.

SOme Turners to shew their Dexterity in Turn|ing, and make others that know not the way how it is 〈…〉〈…〉 the•••• Skill, T••rn long and slender 〈…〉〈…〉 Ivory, as small as an Hay-stalk, 〈◊〉〈◊〉 perhaps a Foot or more long: Which 〈◊〉〈◊〉 they cut a piece of Ivory to its intended l••ngth, but strong enough to bear working till they bring it to as small a Cilinder as they can; which being thus forwarded, they place a Joint Coller (as is described in Turning § 17.) made small and fit for their purpose, just in the middle of their Work: Only that their Work may Bear at a smaller length, and consequently be stronger for being thus supported while it is Turned yet smaller. Then they place other Collers between the Piles, and the middle Coller, and Turn the whole Cilinder slender ••et. And thus by placing Collers where ever they find the Work buckle, they (as aforesaid) with Sharp Tools, tender touches▪ somewhat a loose and fine String, weak Bow, and great care and diligence work the whole Cilinder down as small as they list, either with Moldings, or other Work upon it, as best likes them.

The properest Lathe to Turn this slender Work in, is the Turn-Bench described § 18. Plate 16.

§ XVII. Of the Brasiers Lathe and Turning Tools; and their manner of using them.

BRrasiers that Turn Andirons, Pots, Kettles, &c. have their Lathe made different from the Common Turners Lathe, as you may see in Plate 16. at A, where the Cheeks, Puppets and Rests, &c. are much stronger and the Pikes stron|ger and longer than those the common Turners use. Their Edge Tools which they call Hooks, are also of a different shape, as the Figures of them described at B 1, B 2, B 3. in the said Plate shew, as being bent backwards and forwards towards the cutting end, somewhat like an z. And as the common Turners work with a round String made of Gut, as hath been described in Turning § 1. ¶ 14. The Brasiers work with a Flat Leather Thong, which wrapping close and tight about the Rowler of their Mandrel, com|mands it the easier and more forciably about. Their Thong runs between the Cheeks of the Lathe.

The whole Lathe, and its parts, are made so strong, because the Matter they Turn being Met|tal, is much heavier than Wood, and conse|quently with forciable coming about, would (if the Lathe were slight) make it tremble, and so spoil the Work; as hath been said before.

The reason why the Hook is so turned back|wards, and again forwards, towards the end, is, that they may the better direct the Edge of it as much below the Horizontal Plain of the Pikes as they list, the better (in many cases) to come at the Work: For contrary to Soft Wood, Hard Wood and Ivory Turners, they always dip the end of their Hook below the Rest, that so the Hook resting very steddy upon the Rest, and also against one of the Iron Pins standing upright in

the Rest, and held very steddy forwards to the Work, the strong coming about of the Work a|gainst the strong Edge of the Hook, scrapes off the extuberant Mettle lying in that Sweep.

I need no further describe the Lathe, and other Tools that belong to Brasiers Turning; or more of the manner of using them; because, by the whole proceeding Discourse, these Arguments are largely and sufficiently handled; especially considering I have given you the Figures of them in Plate 16. as aforesaid.

O••ly, their way of Whetting their Tools being different from the Whetting of other Turning Tools, I shall say somewhat to: For they Whet their Ho•••• upon a broad Flat Slate, holding the Hook almost perpendicular, that the Basil of its Edge 〈…〉〈…〉 with the Flat of the Slate; with 〈◊〉〈◊〉 the upper end of the Handle in their left 〈…〉〈…〉 the heavier on it, and clutching 〈…〉〈…〉 of the Blade near the Hook-end in the 〈…〉〈…〉 hand, to guide it: And thus with Spittle, 〈◊〉〈◊〉 Water, rub forwards and backwards on the Slate, till they have sharpned the Edge of the Hook. But if it be a round end Hook they whet▪ they chuse a Groove in the Slate fit to comply with the round edge of the Hook (for they have dif|ferent sized Grooves in the Slate for that purpose) and so in it rub forwards and backwards as afore|said.

§ XVIII. Of Turning Small Work of Brass, or other Mettle.

SMall Work in Mettal is Turned in an Iron Lathe called a Turn-bench. The Figure of it is de|scribed in Plate 16. at C. when they use it they screw it in the Chaps of a Vice, and having fitted their Work upon a small Iron Axis, with a Drill-Barrel fitted upon a square Shank at the end of

the Axis next the left hand, they with a Drill-bow and Drill-string carry it about, as was shewn in Smithing fol. 6. with this difference, that when a Hole is drill'd in a piece of Mettal, they hold the Drill-bow in their Right Hand; but when they Turn Small Work, they hold the Drill-bow in their Left Hand, and with their Right Hand use the Tool, which is commonly a Graver, or sometimes a Sculpter, fit to such Moldings as are to be made on the Mettal.

They begin to work first with the sharp point of a Graver, laying the Blade of it firm upon the Rest, and directing the point to the Work, and lay Circles upon it close to one another, till they have wrought it pretty true: Then with one of the broad Edges of the Graver they smoothen down what the Point left, and afterwards with Sculpters, Round or Flat, or great or small, they work their intended Moldings.

The Circumstances and Considerations in the choice of a Drill-bow and Drill-string for Turning, are the same with what you find in Smithing fol. 6, 7. for Drilling.

§ XIX. Of laying Moldings either upon Mettal, or Wood, without fitting the Work in a Lathe.

I Had, soon after the Fire of London, occasion to lay Moldings upon the Verges of several round and weighty flat pieces of Brass: And be|ing at that time, by reason of the said Fire, un|accommodated of a Lathe of my own, I inten|ded to put them out to be Turned: But then Turners were all full of Employment, which made them so unreasonable in their Prizes, that I was forc'd to contrive this following way to lay Mold|ings on their Verges.

I provided a strong Iron Bar for the Beam of a Sweep: (For the whole Tool marked in Plate 16,

is by Mathematical Instrument-makers called a Sweep.) To this Tool is filed a Tooth of Steel with such Roundings and Hollows in the bottom of it, as I intended to have Hollows and Round|ings upon my Work: For an Hollow on the Tooth, makes a Round upon the Work; and a Round upon the Tooth, makes an Hollow on the Work; even as they do in the Molding-plains Joyners use. Then I placed the Center-point of the Sweep in a Center-hole made in a square Stud of Mettal, and fixed in the Center of the Plain of the Work; and removed the Socket that rides on the Beam of the Sweep, till the Tooth stood just upon its intended place on the Verge of the Work, and there screw'd the Socket fast to the Beam.

To work it out, I employ'd a Labourer, di|recting him in his Left Hand to hold the Head of the Center-pin, and with his Right Hand to draw about the Beam and Tooth, which (accor|ding to the strength) he us'd, cut and tore a|way great Flakes of the Mettal, till it receiv'd the whole and perfect Form the Tooth would make; which was as compleat a Molding as any Skillful Turner could have laid upon it.

Having such good Success upon Brass, I im|prov'd the invention so, as to make it serve for Wood also. And make a Plain-Stock with my intended Molding on the Sole of it, and fitted an Iron to that Stock with the same Molding the Sole had.

Through the sides of this Stock I fitted an Iron Beam, to do the Office of the Beam I used for the Sweep, viz. to keep the Plain always at what po|sition I listed from the Center (for thus the Iron in the Plain wrought about the Center, even as the Tooth in the Sweep (before rehearsed) and to that purpose I made a round Hole of about

half an Inch Diameter near the end of the Iron: Then in the Center of the Work I fixed a round Iron Pin, exactly to fit the said round Hole, put|ting the round Hole over the Pin, and fitting the Iron into the Stock commodious to work with. I used this Plain with both Hands, even as Joyners do other Plains: For the Iron Pin in the Hole of the Beam kept it to its due distance from the Center; so that neither hand was ingaged to guide it.

But note, The Stock of this Plain was not straight (as the Stocks of other Plains are) but by Hand cut Circular pretty near the size of the Diameter of the intended Molding: And yet was made to slide upon the Beam, farther from or ••earer to the Center, as different Diameters of Verges might require.

§ XX. To Turn several Globes or Balls of Ivory within one another, with a Solid Ball in the middle.

YOu must first Turn your Ivory Ball or Globe truly round, of your intended Diameter: Then describe a Circle exactly through the mid|dle, or Equinoctial of the Globe: Divide that Circle into four equal parts, and pitch one point of a pair of Compasses in one of those Divisi|ons, and extend the other point to either of the ••ext Divisions, and describe with it a Circle r••und about the Globe. Then remove the stand|••ng point of the Compasses to either of the next Divisions in the Equinoctial, and in like manner describe another Circle round about the Globe.

But Note, That the moving point of your Compasses must be somewhat bended inwards; for else its point will not describe a Circle on the greatest Extuberances of the Globe, but will slide off it.

Thus shall the Ball or Globe be divided into eight Spherical Quadrants: Describe as great a Circle as you can in each of these Quadrants, and each two Centers of every two opposite Circles shall have an imaginary Axix pass between them: And if the Globe be successively pitcht upon all the rest of the Centers, so as the imagined Axis pas|sing between it and its opposite Center, lye in a straight line with the Pike and the Center of the Coller it is Turned in, the working out of all the Hollows on the Ball will be but common Turners Work, as you will find hereafter. This is in brief the Theory: But to the Practice.

You must use an Hollow-Mandrel, made fit stifly to receive the convexity of the Globe in its concavity, so as it may stick firmly in the Man|drel, in its position: And you must take care that in pitching the Globe into the Mandrel, that the imaginary Axis of the Globe (which is the Line passing between the two Centers of the two op|posite Circles as aforesaid) lye in a straight Li••e with the Axis of the Mandrel; which you may know by examining whether the Circle described with your Compasses (as aforesaid) on the Center (aforesaid) wabble not in a whole Revolution of the Globe, from the point of a Tool applied sted|dy to it.

Having thus pitcht the Globe true, and fixt it fast into the Mandrel, you must begin to work with the Triangular Grooving Point (described in Tur|ning § 5. and Plate 15.) placing the point of it pretty near the Center of the Circle, and work into the Ball with the Grooving Point, and so by degrees make a Hollow in the Ball so deep, and so wide, as you think convenient, I mean so deep from the Superficies of the Globe towards the Cen|ter of the Globe, and so wide from the Center of the Circle described on the Superficies of the

Globe towards that Circle, as it may have a con|venient Substance between this Hole, and the next intended to be Turned.

Thus must every one of the eight Circles de|scribed on the Globe, be successively by the same Rule, and after the same manner be pitcht out|wards, and fixt into the Mandrel, and then Hol|lowed out as the first was. Where Note, That every Hollow is to be Turned to the same depth and width exactly as the first was: Which to do, you must use a Gage made of a thin Plate of Iron or Brass, as is described in Plate 17. Fig. D. whose two sides from a the Bottom of the Gage, to b the Shoulder are the depth of the Hollow from the Superficies of the Globe towards the Center: bb. is the width of the Hollow at the Superficies of the Globe; and aa is the bottom width of the Hollow; and the concave Arch between aa is an Arch that the Convexity of the little solid Ball to be Turned within all the Spheres must comply with. So that when each Hollow is Turned, the Gage must be put into it to try how the sides of the Hollow complies with the sides of the Gage, and also how the Arch in the bottom of the Gage, complies with the surface of the Solid Ball in the middle.

Having thus Turned all the Hallows in the Globe, you must provide several thin and narrow Arching Grooving Tools, whose convex and concave Arches comply both with the Convexity and Concavity of each Globe, or Sphere, to be Turned within the outermost: So that begining at the bottom of the Hollow, you Turn just half way of the Solid Ball loose from the Sphere it is contained in, viz. as far as the Equinoctial of the Globe; and in thus Turning it, you must take great care, that the Solid Ball on its Convexity and the Concavi|ty of the Sphere it is contained in, be both at the ••ame time Turned exactly Spherical.

Thus one half of the Solid Ball being Turned loose, you may in like manner Turn the next Sphere it is included in half loose also: And so successively as many Spheres as you list.

Having thus Turned one half of all the Spheres loose, you must take the whole Globe out of the Hollow-Mandrel, and pitcht and fix the Globe a|gain into the Mandrel, so as the imagined Axis of the H••llow opposite to the last loosned Hollow lye in a straight line (as before was taught) with the Pike and Center of the Coller the Man|drel runs in, and then Turn the other half of the Solid Ball and Spheres also loose, as the first hal•• was Turned.

§ XXI. To Turn a Globe with several loose Spheres in it, and a Solid Cube, or Dy, in the middle of it.

THis is Turned after the same manner the f••r|mer Ball was Turned; only instead of di••••••ding the Equinoctial of that Globe into four equal parts, the Equinoctial of this must be divided but into three equal parts, and their Semi-Circle draw through the divisions into either Pole of the Globe▪ So shall the Globe be divided into six equal parts▪ or Segments; in each of which parts must be de|scribed a Circle, as was described before in the Globes of eight equal parts; and in these six C••r|cles must be made six Hollows, as before there was eight: But instead of working the Bottom of each hollow Spherical, now the Bottom must be wrought Flat: So shall the Cube when these six Hollows are thus made, be formed: And the Hol+lows being exactly of the same depth, and flat in the Bottom, the Cube or Dy will loosen, and each of the six Flats in the Bottom will become the six sides or Faces of the Cube.

The manner of loosning all the other inward Spheres, is as the Former: Only, that was loos|ned with twice pitching the Ball in the Mandrel, because the Centers of the Hollows lay opposite to one another; but to loosen this Ball will re|quire three Pitchings into the Mandrel; because the Centers lye not opposite to one another.

§ XXII. To Turn a Cube, or Dy, in an Hol|low Globe, that shall have but one Hole on the outside to work at.

THe Outside of this Globe must be Turned Round, viz. Spherical, as the former, and fixed in an Hollow Socket (as before hath been taught.) Then must an Hole be Turned in the Globe so deep and so wide as you please, as in the former Globes, and the Bottom of that Hole Turned flat, for one side, or Face of the Cube, or Dy: Then with a Semi-circular Tool loosen the whole Core, or middle of the Ball, and pitch the Core with the point opposite to the Center of the already flatted face of the Dy, outwards against the Hole in the Globe, and so fasten it in this position, by powring in some melted hard Wax, or other Cement; and then with a flat Tool Turn the foreside, (viz. the side opposite to the first side) flat also: Which done, loosen it out of the Wax, and successive|ly pitch the other sides to be Turned flat care|fully against the Hole, so as all the sides have right Angles to each other, and fastning them with Wax, or Cement (as before) Turn them by the same Rule flat also.

Now to make this Thing more admirable to the ignorant Spectator, you may make the Dy as big as you can, and the Hole you Turn it at as little as you can; that it may the more puz|zle the Wit of the Enquirer to find how so great a Dy should have Entrance at a small Hole, unless the hollow Ball were turned in two Halves, &c.