Getting Ready For Bending

It was an unusually cool day for August in Texas, so I spent all day on the plane. Once the last side of the last FAP panel is completed (Monday?) we will be ready to use the Hinged Panel Tool to fold the sides up on the fuselage. Before that could happen I needed to correct a mistake. We had accidentally applied epoxy, but not cloth, to an area that needs to bend, and I needed to remove that layer. Even without cloth there was no way that area of the panel was going to flex like it needed to. Ordinarily that would been sand paper and a lot of elbow grease, but I have The Machine, the 4'x8' CNC router table I built. I built it because I was originally planning on building a metal airplane and wanted to make my own 'kit' rather then using tin snips. The Machine is what I have been using to cut out my foam panels accurately.

 After aligning the panel on The Machine's bed and measuring the X and Y coordinates of the area I needed skinned, a software package I use with The Machine was only too happy to create a tool path for the router to follow. I chucked in a 3/4" mortising bit and, with my hand hovering over the emergency stop button, let The Machine skin off  the 1/25 of an inch thick layer of epoxy. It worked out perfectly.

 
I next let The Machine trim and straighten all of the sides of the 3 finished panels. Basically I had it make multiple passes along each side, each maybe 1/100" deeper than the last pass until I was happy with the resulting edge. Four passes was usually enough. Here is a before/after pair of pictures. The Machine only needed to remove 0.040" to get that edge clean and dead nuts straight.

Lastly, I mixed up some micro (epoxy and glass balloons mixed into a putty) and joined the 3 finished panels together on the HPT. The screws and fender washers are to keep the seams tight as the micro cures.

Time Spent Today: 8.0 hr

First Side of Last FAP Panel

There are four FAP panels, each with two sides. Each side must be sealed with slurry and then layered with one ply of UNI and one ply of BID. This is side number 7...  one more to go!

Time Spent Today: 4.0 hr
I realized today that I have been totaling clock hours and not man-hours, so I am making an adjustment to account for my wife's added time. All future hour reports will be man-hours.

Time Adjustment: +12.0 hours

Starboard Fuselage FAP Panel Glassed Other Side

Kinda skipped out of the groove there for a bit. WE are now in a full-on push to get the other fuselage panel done and the whole thing on the HPT and folded into a basic airplane shape.

It takes two people  about two hours to pre-cut the fiberglass cloth (one ply each of UNI & BID), seal the foam with slurry, and then position and wet out the cloth.

One picture shows the excess epoxy being squeezed out of the layup by the use of a vacuum bag.

Time Spent Today: 2.25 hr

Starboard Fuselage FAP Panel Glassed One Side

Laid on the UNI and BID on one side and then vacuum bagged it.

Time Spent Today: 1.5 hr

Back in the Saddle

Haven't done any work on the plane in almost 4 weeks.  A SCUBA diving vacation to Honduras took up 3 weeks of that; one week to prepare, eight days there, and one week to get back to normal.

Things are back to normal so today I got back to work by getting the starboard fuselage FAP panel ready to lay up, including cutting the UNI and BID to shape.

Time Spent Today: 2.0 hr

Second FAP Panel Glassed Both Sides

Same job as yesterday, just the next FAP Panel aft. There are two FAP panels left. The first two form the cockpit and baggage area (both now finished) and the next two form the tapering part of the fuselage back to the tail. There is a port one and a starboard one.

Time Spent Today: 2.0 hr

First FAP Panel Glassed Both Sides

Finally back in the shop.  I ran out of bagging film and it took a week to get more. I need to get better at keeping items 'in stock' to prevent useless delays like that.

Not much to say tho, we just glassed most of the inside of the forward-most HPT panel. We didn't glass all of the inside, just the parts that are not going to bend when the sides of the HPT are hinged up. This will make sense later.

Time Spent Today: 2.0 hr