To All, I love magnetic coins, but the problem with most is that when CLAD you can see the black if you aren't careful enough. Some put "MAG TAPE" over their magnet trying to make the coin look all silver inside which works till the tape begins to wear out & starts to bunch up. Funny thing is I handle my gaffs well enough not to flash, but I am wondering where I can get that "MAG TAPE" that some use to help out just in case? Anyone have a clue/answer?

To start off, I think we need to clarify some terminology.
By "magnetic coins", I usually think of full-thickness, "normal" coins that have a magnet hidden inside. There are also shimmed coins that are the same but with a ferromagnetic piece, rather than a magnet.

From your description, it sounds like you're more referring to split coins?
But then wouldn't it be seeing copper inside, rather than black?

I think of Mag tape as being quite thick - which would be rather unfortunate if combined with a split, as it would then be 1.5-2x the width of a normal coin. Where do you see that suggested?
Better might just be some grey tape of some sort, but that's still not great.

Other folks use coin-patterned stickers - there's a lot of conversation about this in the DFSTC thread, which does exactly that. You could use it to do an intentional color change to a different "coin", or you could use a sticker of the same coin, for casual displays, but it still wouldn't pass a close inspection. The stickers are sometimes metallic, but not always, and preferences vary.
But paper can increase friction, and then still other folks use optically clear teflon tape on top of the stickers.

It's all about what works for you ... but if you don't have any problem not flashing, then it might be reconsidering whether you actually need a solution for it.

Marty G,
I believe I understand your question and PM'ed you several links to products that address the cosmetics, functionality, and the long term reliability for the "look" that you are asking about.

Is that something that needs to be secret? I imagine future readers would be interested in similar answers - I know I'm curious to learn about what you recommend.