2ND QTR 2005           •   •   • 
04/20/05 1.5 794.4 Back to work!  Why am I working on the rear instrument panel?????  To start out I need to locate the rear instrument panel mounting tabs on the fuselage. The rear ones are already tacked in, but the front side of the inst panel, that goes right behind the passengers head is a little more complicated. Kevin normally mounts that panel flush with the crossmember and at the same angle of the seat back, see pic. I plan to use Microair radios which are a little longer than the panels allow, so I have to move the forward panel out a little on the sides to make room. Rather than making some sort of pop-out I decided to have that panel come forward from just outside of the shoulder harnesses, kinda like the rear panel but opposite.  So...I'll need to use a couple of tabs on the longerons just like the rear panel, but need to figure out where they go. I've also decided to get the panels made up and assembled so I can get the canopy lift strut installed and working. To start out I drew out the front panel in Autocad, then plotted a pattern to make two hammerforms. I'm making my own rear inst panels because I want them bent a little differently than they came from Kevin, plus I want to be able to make spares as needed. Paper plots taped together to make pattern
04/28/05 1.5 795.9 Cut out the rough plywood forms and .050 6061 sheets over on Ken's bandsaw. I then used my oxy-acetylene torch to anneal the aluminum sheet, what a mistake! The heat totally warped the material and its pretty useless. I called Jimmy for advice and he offered some 5052 which would be soft enough to work with without annealing.
05/05/05 1.0 796.9 Cut a new hammerform out of oak which will stand up better. Also sanded a 7 degree overbend into the pattern to allow for springback of the aluminum. Oak hammerform
05/06/05 3.5 800.4 Made a visit to see Jimmy to pick up the 5052. There I learned that the two panels I got from Kimball Ent were made out of 6061-T6 which they must have formed over a steel hammerform without annealing. After I got back I used a piece of scrap 5052 to do a test run with the oak hammerform. With some patient work I was able to get a decent looking flange bent into the panel. Also I ended up increasing the spring back allowance to 9 degrees in the oak hammerform to get a nice 90 in the flange. However I discovered that there's some difference between the front and back panels that make up the rear instrument panel assembly. The rear panel is .35" lower at the height of the radius than the front panel. I need to get Kevin's advice, before I proceed. Just starting to form flange over the oak pattern More forming work done
Flange close, but more springback allowance needed in the oak pattern Differences between Kimball rear instrument panels
05/12/05 3.0 803.4 Took all my radios & instruments on my Maui layover and drew them all into autocad. Came home and plotted them out full scale so I could get an idea what my panel layout might look like. Regarding the question of the two panels, they are different in height because the front panel is leaned back like the seat. I've decided after sitting in there, that having it vertical will not be a problem and they both can have similar heights, but I need to make two hammerform patterns because the forward panel will be slightly wider to match the longerons. I then reinstalled the canopy so I can design my hammerforms to make panels that work with the canopy exactly like the Kimball panels do. See rear instrument panels drawing here. (3/7/07 - See final version of this drawing) Paper instruments on possible panel layout
05/17/05 3.7 807.1 Did several measurements on the areas where the panels go and then revised my rear instrument panels drawing. I plotted them out full scale using my laser printer, which took many sheets of paper cut and taped together, then went over to Ken's and sawed new hammerforms and aluminum blanks with his nice big band saw. After sanding in the extra 7 of bend into the oak forms I then applied cyanoacrylate glue to the edges to harden the wood and increase its resistance to compression. Kevin says to use 6061-T6 on the panels and only anneal the edges, but I'll do that later, I'm going to make some blanks first with the softer 5052 that Jimmy gave me. I suspect the 5052 panels will hold up ok as long as I never let 250lb guys pull themselves out of the rear seat with the panel alone. Hopefully I'll be able to make panels out of both materials before my hammerforms get too hammered. I loaded the fwd panel in and got it ready to go, but didn't think it wise to start hammering away in the garage at midnight. Hammerforming components
Ready to beat on the first fwd panel
05/18/05 2.0 809.1 Cut relief into the flange where the panel will be bent forward, then formed it over the oak. Note that I left the panel flat in the area of the front seat backboard. I will have to make cutouts for the shoulder harnesses there and didn't want a flange interfering. After forming the panel I test mounted it to see how far forward the bend would have to go to allow room for the radio and transponder. I sat in the front seat and found that even without a back cushion the vertical panel didn't bother me, still I didn't weld the tabs on the fuselage yet, I want to think about it for a couple days. Relief cuts New panel test fit
Closeup of mounting tab Transponder is longer than the comm radio
05/05/05 1.8 810.9 Got out the 6061-T6, the rear panel hammerforms and the oxy-acetylene torch and went to work forming the rear panel. I could really tell the difference in ease of forming the aluminum after annealing the edge each time. I heated the edges once before starting to pound on it and then 2 other times before finishing, I was also able to do it without burning the wood. The oak form looks pretty good afterwards, I can't see any crushing yet. Annealing edges of the panel Flanges formed Panel ready for trimming and bending
 2ND QTR 2005           •   •   •