Obsidian plinth dust cover adjustment

Definitely, my SH10-B3 dust covers are raised all the way without falling.
Have you tried checking for loose screws?

There are screws on both hinge sides (the opposite of the cover
''legs'') but I was not able to strengthen the (possible) springs
 with those screws. The dust cover functioned long time as it
should but ''weakened'' later on. The only solution then was to
remove te cover during the play and (re) install back thereafter. 
As I already wrote my solution was to use adhesive tape on the
cover ''legs''. This way the ''thickness'' of the ''legs''  increased
somewhat and this solved the problem. Anyway so far.
My assumption was that ''many'' (?) of our members own 
Obsidian plinth but this assumption was obviously wrong.
There is no sense in asking advice if one can solve the problem
by himself (grin).

You can change the dust cover holders, not everyone use or even have a dust cover, so they could swap the holders with you. You could get a better dust cover holders this way. Just my advice. 

I am working on restored obsidian plinth now for local friend, his obsidian plinth does not have a dust cover, but the cover holders are still there on the plinth (useless). I could ask him. 

@nandric

From the photos I am attaching you will see the hinges broken down and made up of multiple items of the Technics base SH 10 B3.

The bottom screw you see should serve to adjust the spring preload, you should adjust that screw by screwing it or unscrewing it to make the cover dust rise.
Also in the hinges of the plinth of the JVC QL7 there is a similar screw; if you tighten it too much, the lid does not remain raised and slides to the ground if it remains completely "unscrewed" the lid remains raised without any problem.
You just have to try to adjust that screw.

https://postimg.cc/rd3hBbQh
https://postimg.cc/r0P1rk2c

Dear chakster, I lost any hope when our encyclopedic member 
from Russian Federation was silent. One should not believe in
miracles or omniscient persons. Thanks for your specific advice
but I don't need one more  couple of those Obsidian hinge(grin).
Dear best-groove, When I purchased Technics SL 1000,mk2 
there was no user manual included. Despite of this I improved
the Obsidian plinth by removing its mediocre feet and provided 
with Technics pneumatic ''towers''. I was then very proud of myself. That was also the reason why I waited so long to ask for help...
Thanks for your ''input''.