The Explorer had a cracked fillet. The crack survived a few flights on E motors but I wouldn't be confident putting an F in it as it was. I ground out the old fillet, sanded, and then put in a few fillet. I love this rocket and have flown it at many parks and both NCR launch sites. I plan to fly it at the Nov NCR launch (if my Shanelle lets me go).
I'm finally making progress on the Thor. Curtis has been making a lot of noise and I'm even thinking he really is going to get the airframe to me. I used JB Weld to attach the fins to the motor mount tube and am now in the process of putting in large JB Weld fillets. Sometime in the near future, Warren M is going to help me do tip to tip fiberglassing on the fins and then when the airframe arrives it will pretty much just slip on.