For what it's worth

On installing our kitchen units, I ended up with a couple of corner cupboards where I wanted to limit the angle of opening for the doors to a right angle (ie 90 degrees) rather than the 107 degrees that the hinges allow. The manufacturer of the units eventually came up with special clips which limited opening to 86 degrees - and these do the job nicely (as long as you put the clips on each hinge - one per cupboard is not enough). The clips are specific to Blum hinges, but those look to fit standard fixing holes for doors and units) so it could be worth changing hinge type if you hit this problem. I had found it very difficult to track down either the clips or instructions for their use, so here is a link for anyone who finds this posting from a search.