Ways to install a removable base

[Stormrider]

I have these two methods for attaching the base of my panel. It will be a board made of iron: 57 cm x 27 cm x 2 mm. Have you tried any of them? The one on the left has a problem. Apart from the fact that it's a little big, although usable on my 19 mm MDF board, I've tested it and sometimes, when you unscrew, the female piece comes up together with the screw. I suppose adding some glue will be the solution. The other one has the problem that you cannot have the screws installed in a very low level, like with the first one. Here's the photo:

[rackoon]

Why do you want to remove the base? I think if you add some more info you will get more responses .