The Shielded Double Crochet Hook: Two Sizes That Slide Out of One Tube

"When the device is not in use the double ended hook member is entirely within the shield and the cylindrical section 4 thereof is frictionally engaged by said projections 10 whereby the hook member is held against any accidental movement with respect to the shield. By grasping sleeve 7 either end of the hook member may be projected beyond the shield as shown in Figs. 3 and 4, pin 8, or 8a or 8b moving through the slot 2 until it reaches one end thereof after which the combined sleeve pin and hook may be turned to seat the pin in the extension 3 of the slot, this holding the hook member in position with respect to the shield."

Cut 150 mm of 3/8" brass tube. Mark a line along it and cut a 2 mm slot on it with the rotary tool's cut-off disc from 15 mm to 135 mm, with a 5 mm turn at right angles at each end. Deburr with needle files.

Sand 40 mm of hardwood dowel until it slides freely in the tube. Drill each end on the axis for a hook's shank. Cut two hooks of different sizes from the set to leave 50 mm each, and epoxy one into each end.

Cut 20 mm of 1/2" brass tube for the sleeve and drill a 1.5 mm hole through one side. Slide the member into the shield, the sleeve over it, and push a 1.5 mm steel pin through the sleeve and slot into a 1.5 mm hole drilled in the dowel's middle.

With the member centred, tap a light dent inward with the centre punch on each side of the slot at mid-length, until the dowel is gripped but still slides.

Instead of brass and bought hooks, print the parts in PLA at 0.12 mm layers, 100 % infill for the members: - the shield, 150 mm long with its slot and right-angled turns (/uploads/blueprints/shielded-crochet-hook-shield.stl) - the knurled sleeve (/uploads/blueprints/shielded-crochet-hook-sleeve.stl) - a member for your yarn: 3.5/4.5 mm for fine yarn (/uploads/blueprints/shielded-crochet-hook-member-3_5-4_5.stl), 5/6 mm for medium (/uploads/blueprints/shielded-crochet-hook-member-5_0-6_0.stl), 6.5/8 mm for bulky (/uploads/blueprints/shielded-crochet-hook-member-6_5-8_0.stl) Every member has the same 10 mm core, so one shield takes them all. Print members standing upright, then join sleeve, slot and member with a 2 mm steel pin, as in step 6.

US 1,269,014 drawing sheet, public domain (expired patent).

Pull the sleeve with the force meter to unstow the member; note the force. Lock each hook out, shake it hard ten times, and check it has not moved. Crochet a 20-stitch chain with each hook and time it.

**Warren H. Stansbery** of Grand Haven, Michigan, filed US 1,269,014 on 27 February 1917; it was patented 11 June 1918. His sleeve has a knurled surface, convenient for grasping in crocheting; he showed a screw, a headed connector and a straight pin through the slot, and wrote that the straight pin "is the way that the device has been actually constructed." **Honest limits.** He gives no sizes; ours are examples, and a dowel with two bought hooks stands in for his one-piece member. Your forces and times are the result.