Most of those old razors have a crack in the handle. If you are lucky, it's small and doesn't affect the function of the razor. Brazing has a very high failure rate. You can google repairing crack in gillette old type for the best fixes. (JB Weld and clamps) done correctly, the crack will be almost invisible. Better yet, that repair isn't considered a value killer for re-sale down the road, imo.
Thanks! Im just afraid if I keep using them it will open more. Im always super carefull when I close it.
I've never heard of the cracks getting bigger from regular use, but I suppose there's a first time for anything.