can i remove a bad dustcap and redo it with a new one or will things go bad fast like the glue focal uses on there things does not come off well at all
this in not a focal sub

 

go ahead itll be fine

 

Describe what is bad about it and we can help better. A picture would help. Only you can judge if you have the skills needed to repair it better than it looks now. If it is only pushed in a bit you may be able to pull it out. Use sticky tape to pull it back out or a vacuum.
Some punctuation would make your post easier to read.

 

dont take it off, just put a new one over the top.

sand the old one down a tad, before you stick the new one on. it will hold better.

 

related question on this topic, what kind of adhesive can you use for caps?

 

carfull if you leave the old one.. If it is loose and you put a large one over it. it will rattle. ...a good acrylic adhesive available at a crafts store.. but good old white glue will work fine also. depents what your dust cap and cone is made out of! paper? plastic? aluminium?