I worked with a builder assist program and I learned a few things.

So the great thing about builder assist is that you get to speed build your plane, usually the empennage. You also get practice at riveting around a bunch of guru plane builders. So, in like 9-10 days business days you will have months of work done.

There are a few things that are bad about this program in my opinion. There will be mistakes. Even the pros have issues. You have to make sure they build the plane the way you want it done. The BIG problem. The real big problem is that are your parts are cut, buffed and primed for you. You show up and they lay out the parts and have you rivet everything. You really just do what they say and they help. This is great, right? Not exactly! When you go home you have to measure cut, drill, buff, prime, and rivet your parts, BUT you have never done this before. So really you are starting from scratch. Learning how to make parts with proper edge distances for rivets can be tough, as first. You won’t learn this with builder assistance.

The plans require many of the plane parts to be cut to within 1/32 of an inch measurements. So if you are slightly off cutting or buffing then you have to build the part over or do a repair. You also need to learn how to think like a plane builder and this takes time and practice. You need to learn to think about where the part is getting installed and what other parts are going to be connected to it. I’ll try to get a pic of a good example.

For now, here is an example. If you have a longeron, angle iron that attaches to the top of the sides of the body, that needs a notch cut out on the top to fit around the bulkhead and mess up that measurement by a 1/32 you will have a problem. So you cut it and put the bend in the back to match the curve of the body. You cut the notch out. Looks great. You drill all the holes of the fuselage to it. Then you haven’t thought about what attaches to that longhorn and realize that a plate goes over the top of the longeron covering to the notch you made. See you haven’t learned to think like a plane builder and now realized that a river gets installed right near the notch on the top. The 1/32″ mistake actually used up the side clearance margin and now it is too close (out of spec) to install a rivet. If you had a plane builder mindset you would have thought about how that part functions and made a more conservative notch cut to start with. These are the things cutting building your won parts teaches you.

Truth: All builders have extra parts bins. We all have rebuild the parts a few times. No big deal and move on!