Here's the inside of the battery compartment, and you can see the threads in the hole... just enough thickness to make a good strong fastener. Nylon on styrene should last a long time.
Outside of the battery door. You can see I didn't deburr the hole (yet) and it looks oblong, but its not. Also note - thats how far the door sticks out with the two bottom rear tabs broken off (on EACH of two flashes... jeeze!)
There's the thumbscrew in place. Yes... its a little Frankenstein looking, but serves well, and... if I want I can capture it on a little piece of fishing line so it won't get dropped accidentally. Yes, I'll carry a spare - its two for 75 cents at Home Depot.
Broken tabs. You can see they broke outward, as if the batteries were pushing excessively on them. Thats exactly what happened! No abuse. Literally both units were on my desk, bench, or coffee table as I tested them for use together. Both flashes had remnants of broken tabs (before I took the pictures or considered a fix) that clearly showed the force was from within - pushing out.
With the case halves pulled apart, thats the pin that must be finagled out of its hole to change the door. Best way is to scrape along the pin next to the spring with an Exacto blade... so that you can have the end of the pin peek out of its hole, then grab it wtih tweezers. This procedure is not needed if you just plan to add the screw!
Two pictures of the screws that need to be removed if you plan on taking the case apart. Those two, plus the ones on the shoe have to come off to open up the case. I only did so out of curiosity - to see what changing the door would entail. Note the one screw has an anti-tamper date code sticker over it, which I destroyed in the fix. These screws only need to be removed if you're changing out the door.
Lots of real estate space inside the flash... no problem fitting the screw, or later on, putting in a power jack for 6v power.
Shoe off. Notice the very nice build quality, neat job they did with the wiring. This is so typical... they put a lot of engineering thought into the real working guts of the unit, and its production, and totally missed on the tabs that keep the battery door closed.
Two of the four bottom screws that need to be removed to get the shoe off.
Technically... the shoe need not be removed to make the hole, and tap it for the screw. But, you'll see some black wires in there that "may" get in the way of a drill bit or tap. Better to remove the shoe, hold the wires clear while making the hole. I did my "drilling" by hand, putting the drill in a miniature chuck and just used hand pressure and rotation to make the hole. The relief hole in the door was 5/32 inch. The hole in the body (and orignally in the door) was whatever was provided in the tap/drill kit from Home Depot.
I hope this saves some of you blokes 'n birds a bit of grief, and allows you to keep on shooting. Been told as well that the YN565 has the same issue at times. Again... not the best of fixes perhaps, but it certainly gets the job done and keeps you shooting for another bit of time.
Now... off to Biketoberfest for the big test of this Franken-rig of a lighting setup.