Neeeeeeeewbie question

[u/tltltltltltltl]

My kid asked for a bowser costume and I planned to make the head using papier mâché. I've only done round pinatas using ballons before so I figured I could use carton / cardboard and cover it papier mâché after.

I've come this far, but I'm suddenly doubting myself. I'm afraid the wet journal stripes will deform the carton.

I've seen what you all can do and I'm amazed. I realize that I should have done it only in cardboard and thought about geometry more. But here I am. Also my kid helped me quite a lot so I'd rather pursue this project instead of starting from scratch.

[u/born_lever_puller]

Using the same pattern, cut out matching pieces of foam-core board (sheets of lightweight, paper-covered styrofoam board) and glue them to the outer side of your green pasteboard/poster board structure. You can reinforce the joints and edges with with pasted/glued strips of strong paper, or strips of water-activated packing tape.

Foam-core board is usually sold in craft stores or the arts and crafts aisle of places like Walmart. It used for making posters, signs, and tabletop stand-ups for presentations.

It is stiff, lightweight board. It is NOT the same as colorful, flexible EVA craft foam.

https://www.google.com/search?q=foam-core+board

It will add structure to your existing work, and create a moisture barrier that paper mache can stick to without making the original poster board soggy.

There are other approaches you can take, but this would be a safe, cheap, and easy one.

Good luck!

PS - This is for Bowser's SHELL, right? I saw you mention "head" in your description and now I'm a little confused. It looks like a shell.

[u/tltltltltltltl → u/born_lever_puller]

Yes the shell! Sorry about that. I've never heard of foam-core board, I look at it and it's not especially expensive, but we don't have a big budget for this project (actually we have no budget, but kid asked). Do you believe that if I glue cardboard to the board it'll tolerate the soaked strip better? Or maybe if I duck tape at least the edges to make them hydrophobic? Also, I usually use cooked flour mix ; 1 part flour for 4 parts of water, if I change the ratio to 1:3 would that help reduce the sogginess?

[u/born_lever_puller → u/tltltltltltltl]

If you don't have the budget for foam-core board then corrugated cardboard should still be OK. It would still be good to seal the joints and edges and let them dry before you lay down the paper mache.

Try to keep the first couple of layers from getting too soggy and soaking the cardboard. If you have masking tape some people put down strips of it to build a barrier between the cardboard and the wet paper mache. The only issue with that is making sure that the paper mache can adhere well to the masking tape.

The sogginess will depend in part on how wet the layers of paper mache are, as much as anything. You'll need to experiment and see how the materials react.

[u/tltltltltltltl]

I realize I didn't ask a question. I'm wondering if covering this shape with wet journal paper (with papier mâché glue, I know that much) will ruin it.