Mechanick exercises, or, The doctrine of handy-works by Joseph Moxon.

§ VI. Of Mandrels. And ¶ 1. Of Flat Mandrels.

MAndrels are marked F 1. F 2. F 3. F 4. in Plate 15. There are different Sorts of Mandrels, and the sizes of them also different, according to the sizes of the Work.

1. Broad Flat Mandrels marked F 1. in Plate 15. with three or more little Iron Pegs, or Points, near the Verge of its Flat: And these are used for the Turning Flat Boards upon. For the backside of a Board placed Flat upon it, will when screwed up tight between the Pikes, by help of the Iron Pegs, remain in its place and position, whilst the Flat side of the Work is working upon.

Behind the Backside of this Mandrel (and indeed all other Mandrels) is fitted a long Shank, or Rowler, for the String to be wound about while the Work is Turning. This Rowler must be so large in Diame∣ter, that the String wound about it may command the Work about. If the Work be large and heavy, the Rowler must be bigger than if the Work be light; for else the String will not command it about: But if the Diameter of the Rowler be smaller, the Work comes so much swifter about. The Rowler must also be so long between its Shoulers, that it may conveniently contain so many Diameters of the String as shall be necessary to wind about it.

This whole Mandrel is marked F 1. in Plate 15. •• The Round Flat, or Face, of the Mandrel. b The Row∣ler. cc The Shoulders of the Rowler. ddd The Pegs.

¶ 2. Of Pin-Mandrels.

2. MAndrels are made with a long Wooden Shank, to fit stiff into a round hole that is made in the Work that is to be Turned. This Mandrel is cal∣led a Shank, or Pin-Mandrel, and is marked F 2. in Plate 15. And if the hole the Shank is to fit into be very small, and the Work to be fastned on it pretty heavy; then Turners fasten a round Iron Shank, or Pin, of the size of the Hole it is to be fitted into, and fasten their Work upon it, These Mandrels with Iron Shanks are used by Turners that Turn Bobbins, or such like Work: Because a Wooden Shank to fit the small Hole though the Work would not be strong enough to carry the Work about.

¶ 3. Of Hollow-Mandrels.

3. THere is another sort of Mandrels called Hol∣low Mandrels, described F 3. Plate 15. It is both a Hollow-Mandrel, and also used to Turn Hollow Work in it. This Mandrel hath but one Center-hole belonging to it, viz, at the Rowler End, or Neck; but it hath a Shank, which supplies the Office of another Center-hole, a the Hollow, b the Shank, or Neck. The Hollow is made so wide, that the Work intended to be Turned Hollow in it may fit very stiff into it, and so deep that it may contain the intended Work.

When it is used, it is pitcht upon the Center at the farther end of the Rowler, and hath its Shank put in∣to one of the Holes of the Joint-Coller described in Plate 13. fig. G. that will best fit it: which Hole stand∣ing directly against the Pike in the hinder Puppet, and

receiving the Shank into it, guides the Mandrel about, as if it were pitch upon two Centers: And the Work being forced stiff into the Hollow of this Mandrel, will be carried about with it, exposing the Fore-side of the work bare and free from the Joynt-Coller, and not im∣peded by Spikes from coming at the work: So that with the Hook, Grooving-Hook, Gouge, or Flat-Chissel, accord∣ing as your work requires, you may come at it to Turn your intended Form.

Hollow Mandrels are also used in Collers that open not with a Joynt; but then the Spindle is made of Iron, and hath a Screw just at its end, upon which is screwed a Block with an hollow in it, made fit to receive the work stiff into it.

¶ 4. Of the Screw-Mandrel.

4. ANother sort of Mandrel is called the Screw-Mandrel, and is marked F 4. in Plate 15. a the Rowler of the Mandrel, b the Shank, or Screw, is made of Iron, having its two ends Round, and in the middle between the Round ends a Square the length of the Rowler, and this Square is fitted stiff into a Square Hole made through the middle of the Rowler that it turn not about in the Square Hole. In each Flat-end of this Iron Shank, or Spindle, is made a Center-Hole, whereinto the Pikes of the Puppets are pitcht when this Mandrel is used. This Iron Shank, or Axis, must be made very straight, and ought to be turned upon the two Center-Holes, for exactness; Because on one of the Round ends, or sometimes on both, a Screw, or indeed several Screws of several Di∣ameters is made. That Screw next the end of the Shank is the smallest, viz. about three quarters of an Inch over, and takes up in length towards the middle

of the Shank, about an Inch, or an Inch and an half; and so far from the end of the Shank it is of an equal Diameter all the way: And on this portion of the Shank is made a Male-screw of the finest Thread. The next Inch and half (wrought as before) hath another Male-screw; but about half a quarter of an Inch more in Diameter than the former, and hath its Threads courser. Another Inch and half hath its Diameter still greater, and its Threads yet courser. And thus you may make the Shank as long as you will, that you may have the more variety of Sizes for Screws.

These sorts of Mandrels are made for the making of Screws to Boxes, and their Lids, as shall be shewed in the next Paragraph.

¶ 5. Of Sockets, or Chocks, belonging to the Screw-Mandrel.

TO this Screw-Mandrel belongs so many Sockets as there are several sizes of Screws on the Shank. They are marked F5. in Plate 15. a the Socket, or Chock: b b, the Wooden Pin, c the Stay, d d the Notch to slip over the Male-screw.

These Hollow Sockets have Female Screws in them, made before the Notch to slip over the Male-screw of the Screw-Mandrel is cut. The manner of making Female-screws is taught Numb. 2. fol. 29, 30, 31. on∣ly instead of a Tap (used there) you use the several and different sizes of Screws made on the Screws-Man∣drel to do the Office of a Tap into each respective Socket; which Sockets being only made of Hard Wood, it will easily perform, though the Shank, or Axis, be but Iron.

Therefore (as aforesaid) to each of the Male-screws on the Screw-Mandrel is fitted such a Socket, that you

may chuse a Thread Courser or Finer as you please: But this Female-screw is open, or hath a Notch on one side of it, that it may slip over the Male-screw, and the Threads of each other fit into each others Grooves; and when they are thus fitted to one another, the fur∣ther or open side of the Male-screw is gaged in, or pin'd on the Female-screw with a Wooden Pin thrust through two opposite Holes, made for that purpose in the Cheeks of the Wooden Sockets, that it shake not.

When the Treddle comes down in working, and the Socket is fitted on its proper Screw, and pinn'd stiff upon it, and the Stay held down to the Rest of the Lathe, then will the Socket, and consequently the Stay slide farwards upon the Male-screws; so that a Tool held steddy on any part of the Stay, and applied to the out or inside of your Work; that Tools point will describe and cut a Screw, whose Thread shall be of the same fineness that the Screw and the Shank is of.