How to Fix A Broken Latch on a TA-1/PT Field Phone Case
This one's for my homies in the One Shepherd community, the Brushbeater community, or anyone else who still appreciates the value of the venerable USGI TA-1/PT Field Telephone. Easy to use, easy to fix, produces no RF signature, and as of early 2021, you can still buy these on ebay for $75ish. Problem is that they've often had a very hard life.
I bought one on ebay and its black plastic carrying case came with a busted latch. The lugs that hold the latch shut have cracked off, a common problem I suspect.
Left: an intact latch. Right: my broken latch
Common latch on weatherproof cases, the metal bar catches the hooks then cams downwards, yanking the lid on tight.
Fortunately it's an easy fix. You'll need a #6-32 x 3/4 inch round head machine screw, a screwdriver, and a power drill with some drill bits.
Start by snapping/cutting off any bits of the old plastic lugs still on there. Next, drill a hole directly between where the two lugs were, about level with where their bottom edges met with the surface of the plastic case. See my photo of the broken latch above to see where to drill.
Start off with a bit slightly smaller than the machine screw, like 5/64. Drill all the way through the lid. Try to screw in the machine screw. The goal is to drill a hole that the screw can thread itself into. You may need to make the hole bigger. I re-drilled it with a 3/32 drill bit, and then used a 1/8 drill bit but only went a millimeter or two deep.
Once the hole is big enough, screw the machine screw into the hole, leaving 1/4" to 1/2" including the head sticking out. You may need to screw it in and out to get it right.
And there you go! The latch will hook onto the head of the screw, and cam correctly, holding the lid shut.