Help. MH20GT won't turn on when tube is fully screwed tight

Flashlight Modding and DIY Parts
1

Hello,

I have an old MH20GT which unfortunately won’t turn on when the battery tube is tightened past ‘99%’. So completely tightening, or tightening to what would be considered a normal amount won’t allow it to turn on. It’s become a very fine art tightening it the right amount to enable powering on.

Does anyone know what the issue could be or how I can troubleshoot?

Thanks all

2

If you can, loosen all retaining rings, jiggle/reseat whatever they’re retaining, then snug ’em back up.

3

This is quite common if light it left unused for prolong period. I would suggest to thorough cleaning for all metal contacts including battery.

4

Yep, oxidation, “flexing”, etc., can loosen contacts and make things go mental after a while.

Plus, inadvertent loosening after repeated screw/unscrew operations, even lockouts.

I had a TK05 (AA) go mental for no reason after literally just trying a few cells 2-3 times. The RR on the tailcap just loosened to the point it almost fell out.

5

I used to add a tiny drop of Loctite for my own custom Convoy.

6

Thanks, what would the Loctite do, and where would I apply it, the threads? What solutions do ya’ll recommend for cleaning the contacts?

https://www.bunnings.com.au/wd-40-specialist-290g-fast-drying-contact-cleaner_p6100409 would this work? or i’d need a high purity alcohol?

7

For cleaning? Scuff with fine-grit, wipe with an alcohol pad like you can get at CVS or whatnot. Or just IPA on a tissue.

Me personally, I don’t bother with loctite and just snug up any rings with ring-pullers (“snap-ring pliers”). I don’t like anything that might “pollute” the threads, but you decide if you want it to be semi-permanent or not.