I built my own supers. Many of them are suffering from the same problem as shown in these photos:
https://imgur.com/a/d7rekACI've noticed that the joint is the weakest part of the super. It's probable that water is able to seap in through here. That, added with all the weight from the honey, seems like it's causing my supers to split apart slowly over time.
I used glue and nails initially to fix the sides together. It seems like I used a poor quality glue as over time it's appeared to shrivel up and not actually help the sides stick together. I tried to redeem this by adding screws, which has helped but regardless over time they're still bending apart as seen in the photos.
I'm not sure what to do at this point in time. I could tear apart the supers, take off all the sides and then put them back together with fresh glue, nails and screws. I'm not sure if it's going to be possible to straighten out the bends much. I could also try using a clamp to apply pressure for it to push back into itself, then use a screw to hold it in place.
I figure though that if I was to do this, in a few years time I'll have the same problem. I've been thinking about getting scrap pieces of metal, to put around these corners to not only apply some physical structure to hold it in place, but to act as a physical barrier to mitigate water ruining the corners.
I'm pretty unsure and inexperienced when it comes to this stuff so any feedback is appreciated.