Very pleased with the bike carrier I created for my car, I decided to take my bike into work with me today for a noon ride. Less than 2 minutes into my commute, one of the two handlebar grip brackets failed catastrophically. The plywood I used to build the holders delaminated along a plane containing a wood knot. Fortunately, I had the foresight to add a safety strap to my design which prevented my bike from spilling into traffic. It was my plan all along to replace the rather crude looking prototype wood blocks with an elegant 3D printed part from a MarkForged printer. Looks like I will need to do that sooner rather than later paying particular attention to part strength which is clearly going to be an issue.