I am restoring and re-veneering a pair of 4312As. Recently I removed the grille cloth from both grille frames and found that one of them had broken half way up one of the long edges. I think it may have already been broken but the cloth was holding the break together. To prevent the other side from breaking I used Titebond II to (temporarily?) fix the break.

The frames are particle board, and are very thin along the sides (< 3/4 inch). Before I removed the cloth I noticed they were both bowed inward, probably from the stretched fabric pulling the long sides together.

I am thinking about ways to improve the 'fix', or possibly options for replacement.

One option is to use a thin synthetic cloth with CA glue to make a much stronger joint at the break. It's similar to using fiberglass (fibers plus epoxy) and I have read it can work well. Note that gauze is off the table because cotton will react with CA and heat up/burn.

My other option is to look for some 5/8" plywood and try to make new frames. I kind of like making something tougher than the original, and not deformed like the original. But I live in an apartment in Spain, and my tools are limited. No router, saw guides, etc. Just a jigsaw for cutting.

I could also draw it in CAD and try to find a local CNC place but that might be a bit expensive.

What would you recommend?