Turnbuckles and Bottle Screws

This article was published in The Model Yacht, Vol 5 No 2, Fall 2001
See the Step-by-Step article “Turnbuckles” from The Model Yacht, Vol 24 No 4, Summer 2023
As you may have gathered from John Snow’s article, the A.J. Fisher Co. is no longer in business. This deprives us of our only source of vintage fittings. Many fittings, such as Braine quadrants and goosenecks, can be made with greater or lesser effort. Turnbuckles and bottle screws, which are used to tension shrouds, are another matter. We have two items to help until we are able to develop another source of supply. One is a an article by Jack McKie that tells how to make a simple bottle screw from K&S and Special Shapes material sold at most hobby shops and MicroMark. The other is a self-explanatory set of drawings by Vic Smeed on simple tensioning fittings.

A turnbuckle, strictly speaking, has two threads, one right-hand and one left-hand. A bottle screw has one. Most people use the term “turnbuckle” for both.

A Simple Turnbuckle

Jack McKie

Not a beautiful fitting but cheap and relatively easy to make and I think very functional. This might help some folks get boats in the water until we have a new source of Fisher type turnbuckles.

Materials:

  • K&S 5/32-in Brass Channel
  • K&S 1/16-in Brass Rod
  • K&S 1/16-in Internal Diameter Brass Tube
  • Special Shapes 1/8” Square Brass Stock
  • Solder

Tools:

  • Drill press or very good hand/eye coordination and
  • Dremel tool w/chuck.
  • Solder, Flux, and Torch
  • .070 Drill.
  • 2-56 tap and wrench 2-56 die and die stock
  • X-ACTO® saw

To Make:

  1. Cut length of channel for body and set aside.
  2. Cut a short length of 1/8-in square stock ~1 in for ends.
  3. Smooth off end of square stock. Mark center of square stock.
  4. Center punch location of hole fit in drill press vise.
  5. Drill.070 hole about 5/16 in+ deep.
  6. Cut two 1/8-in pieces with hole in center. Use fine file to clean up burrs.
  7. Solder 1/8-in pieces in ends of channel. Mind the hole orientation and use minimal solder.
  8. Use 2-56 tap to put threads in one end. Cut length of .081 rod. Clean up the end and cut 2-56 threads.
  9. Using a hammer and blunt punch smash one end of the threaded rod and drill hole for stay.
  10. Cut length of tube about 1/16 in long. Solder piece of tube to the 1/16-in rod end.
  11. Cut 1/16-in rod with tube so that it is just short enough to fit between ends and insert through the unthreaded end.
  12. Form eye in 1/16-in rod to suit.

A simple turnbuckle, made from sheet stock and fasteners

Vic Smeed

The above sounds harder than it really is. It takes me about an hour to make four. What I would really like to see is real looking turnbuckles with lost wax cast bodies at a reasonable price. The only tough part is finding left-handed taps and dies.

Afterword

Small Parts sells telescoping hexagonal brass tubing, which means that you could use a brass 2-56 nut and save the tapping step. Likewise, they sell 2-56 threaded stainless rod; this would require heating to red hot to form the flat on the end, but would save the trouble of threading. Small Parts is also a source of high quality taps and dies, both right and left handed. If you come up with a design of your own for a home-made turnbuckle, let us know and we’ll run it in an upcoming issue.