On my 3 UCD's, all of them had the gear block area come loose,the 2 formers come loose too. You can add tri stock vertically to the formers and then I also put in a big block of hardwood in the middle of the 2 formers to lock them together. I used Pro Bond polyurethane expanding glue,lighter than epoxy& less is needed,fills any gaps. Part of the problem can be oil-if any gets on the glue joints, the glue used during assembly will soften & peel off,I coated all the joints with thinned epoxy to keep the oil off.