I have been around this thing for a long time and this subject keeps coming up. I think that the consensus is that the single bolt, with spacer, is the way it should be done. However, I will bet that there are at least as many done with a bolt in each attachment as there are with the single bolt and spacer, and in neither case, has there been a wing failure at the attachment. So in practice, it is most likely a mute point.
I use a bolt for each attach point, because getting a single bolt through both, with a spacer in between, would be an impossible task on my plane, unless I line bored the holes oversize. The alignment must be perfect to start with, or I think you will do more harm than good. Also, some people are just better at doing things like that, than are others. Your results will vary. See N64KR at http://KRBuilder.org - Then click on the pics See you at the 2011 - KR Gathering in Mt. Vernon, Il - MVN There is a time for building and it never seems to end. Daniel R. Heath - Lexington, SC
