Making and mounting a hooked pin
There are two recipes here: one for a basic mounted hooked pin and one for the new improved Washington hooked pin.
The basic mounted hooked pin
You’ll need a headless entomological pin. If you don’t have any headless pins, snip the head off a headed pin with wire-cutters. Holding the pin firmly in pliers, press the point hard against a pane of glass and drag it to one side, keeping it at about 90º to the glass. Examine the tip under the microscope to see if you have rolled a satisfactory hook onto the end. You might need a few goes. Surprisingly, this causes no perceptible damage to your windows!
Larger pins can be mounted in the Watkins & Doncaster needle chuck (D431 Universal needle holder). But you might just as well mount the pin in the end of a matchstick, a piece of thin dowel, or an old pencil. Holding the pin with pliers again, push the non-hooked end into the wood. To make it easier, you could make the end of the pin sharper by snipping it diagonally with the wire-cutters. Once you’ve made a hole, take the pin out again, dip it in superglue or epoxy resin and then glue it back into place.
The Washington hooked pin
Clive Washington writes: “I have never been a fan of the plain ‘hooked pin’ for extracting genitalia. It is generally too springy and can easily catapult the specimen across the room [too true!]. It’s also easily damaged or bent, and when mounted in a pin chuck feels badly balanced and clumsy. I thought it would be a good idea to have a much thicker stiff pin with a very fine end. These are actually available from specialist microscopy suppliers for a frightening price.
My solution to this problem has been to use a syringe needle as a handle for a hooked micropin, with an appropriate length of the micropin protruding from the hollow end of the needle. In my case I use a B3 micropin which has been hooked by brushing it across a glass plate, then I put a bend of about 30 degrees in the centre of the pin. Using fine-nosed jeweller’s pliers I then push this kinked pin into the sharp end of a 27g 0.5 inch long syringe needle. When the bend on the pin enters the needle it will of course take quite a lot more force to push it into the needle (that’s what holds it in of course) so be careful not to slip and impale yourself. My preference is to leave about 2mm of the hooked micropin sticking out of the syringe needle end. You can make different sized versions but this small one suits me. I’m quite comfortable holding the syringe needle by its plastic hub but if you want a larger grip then the needle can be mounted on any sized plastic syringe barrel.
Since making this tool I have dissected several dozen Stenus, various Staphylinini and some flea-beetles and have not yet lost a specimen. The needle is much stiffer than the plain pin and handles sensitively. It’s still in good, unbent condition and when it does start looking tatty then it is the work of a few minutes to replace the whole thing afresh.”