Quickly flipping through all the possible that have been given one thing comes to mind when drilling the hole the tube does not need to be a tight fit in the blank as all you are doing is to rub of the adhesive therefore giving little to stick the two together. The tube should slid through the blank but not to the point of it moving about to much, like Flexi I measure each tube and find a bit to suit and don't rely on the said sizes by manufacturers.
I use either epoxy resin glues or the polyurethane expanding type glues and found that I don't usually have any problems unless I do something stupid. Getting a catch can break a bond either as you have found or the blank just breaks up completely