How to harden cardboard

Hi everyone!  I want to make the initial of a name as a door decoration for my first granddaughter.  The letter is made of cardboard and I want to make it stiff so it doesn't bend with time.  I am going to use wool thread to cover it.  Appreciate any help given!!

johanx42 months ago

Glue several layers of cardboard until you get the desired thick. Use liquid glue, avoid those bars glue. Imagine that if you are using 1/4" card board, you only need 4 to get 1", which would be more than enough for what you need to do.

caitlinsdad2 months ago

Just glue on several more layers of cardboard so you have a thick lamination. If you have a 3D shape with hollow insides, just glue in lots of cardboard partitions to act as braces and support for the outside "box" or shell. You can coat all over with glue to finish it off. If you really want to do the work, you can paper mache your base letter form and give it a few days to harden up when it completely dries. Good luck.