From: Mark Byrd
* The wood used for the base is Jatoba, which is similar to Mahogany in appearance, but denser. I do the simple finish - 3 or 4 coast of rub-on gloss poly, followed by a couple of coats of satin spray poly.
* For the crystal detector cup, I purchased a brass fitting from Harbor Freight (Item 47986) that converts an air hose down to an airbrush size hose. I turned it by chucking it in my drill press, using a file and then progressively finer sandpaper. To remove the threads on the inside, I used a cylindrical diamond carving bit for my Dremel tool. I just held the bit it in my hand and worked the inside while spinning the brass fitting on my drill press.
* For the detector stand post, I used 3/8" solid brass rod. I made about 10 at once. I started by boring the horizontal hole 3/4" from the end, then clamping the rod vertically in my drill press vice to bore a hole from the end to intersect the horizontal hole. I threaded this hole with an 8-32 tap. I cut this section off (total of 1") with a hacksaw and smoothed the ends on a disk sander. Repeat for additional posts if desired. Inside the stand is a small ball bearing and spring held in place by the bottom mounting screw. This gives excellent stability/stiffness when adjusting the detector arm. The detector arm is just a rod, threaded on both ends. The cylindrical threaded brass nuts that hold the cat whisker are simply brass nuts turned round again on the drill press.
* I have purchased the 1/2" Delrin from a couple of suppliers. It costs about $30/sq ft, and you can make two of these radios from one sq ft.
* The Delrin cuts well on a table saw with a 40 to 50 tooth blade. I used a scroll saw with a 12 tooth blade to cut the semi-circle.
* I used forstner bits to recess all screws in the panel, the crystal detector base and the wood base. Most holes in the Delrin are tapped.
* The terminals are brushed nickel plated brass, readily available from my local electronics store (ACE electronics in Houston)
* The tuning capacitors are Pilot Capacigrads. They were cleaned using Mike Starcher's method - first in an ultrasonic cleaner, then dipped in Klean-Strip Phosphoric Plus with one part clean water plus a tablespoon of Downey fabric softener. Then coated with clear satin spray poly.
* The coil form is a 3" paper-based phenolic tube, purchased from a model rocket store, then painted with a mocha colored paint (not my favorite). In my current project, I'm staining the same tube with mahogany stain, followed by a coat of satin spray poly. The windings are 25AWG silk-covered wire supplied by Kustomwire (frequently selling this wire on eBay).
* Wiring is 0.064" square bus wire available from Antique Electronic Supply.
* The vernier dial is a 4" BMS dial.
I built a very simple coil winder, with a turns counter, for winding the coils. The cones on the winder were made from a boat trailer bow guide, purchased at Academy Sports for $4.