Pacific Ace 74 inch
Crashed a trainer last month. My fault before I even started the engine. Was using my old Futaba 7uaf on 72 mhz as I was out of 2.4ghz receivers.
The plane was a pretty touchy on the controls last time out. So I added some expo while waiting in the pitts. Unfortunately I added + expo, not -. What a wild ride to I finally found the ground. And that was that for that bird.
I haven't' had much opportunity to fly since around 1997. To say I am rusty would be an understatement. I have been blessed to find great club about 45 minutes away that caters to vets. 40$ dues, 7000 feet of runway (yep SEVEN THOUSAND). It's an abandoned military runway. But it is the opposite pattern to what I learned and did probably 95% of my flying in. So I do need to build my skills again and get lots of practice with this counter clockwise pattern.
So I wanted a replacement Trainer. And it was just something I sort of just threw together. But I did not want to just build a new version of the one I had crashed. The wife liked the transparent orange I had covered the wing with (what I had on hand). So the replacement seemed it should likewise have transparent covering. So my thoughts turned to Pacific Ace.
I built Pacific Ace 74 inch once before while my ship was swinging on the hook off the coast of Kuwait during the first gulf war (mine clearing). Well I got all the framing done anyway. And then finished it when I finally got home. Learned to fly on it. Did some thermal soaring with it when the engine died. Some fairly long flights.
When the wing survived beyond the fuse I used it for slop soaring. Had some great flights when the wind and slope lift died and was thermalling. Got lots of comments from my buds on the slope.
So I showed my wife the pics I had scanned of the my old Pacific Ace. Showed her the original planes I still have (yellowed and fragile). She loved it. But she loves stick construction anyway.
So that settled it was time to get ready to build a new one. I also just happen to have the plans scanned as well. I tile printed those out and slowly over several days taped them together, but just sections. The Wing the fuse, tail feathers. Much easier to work with.
I hit the hobby shop for some lumber (OUCH$$$) Christmas eve.
Had to make a number of substitutions buying wood, as they did not have what I needed. Bought 1/4" sheets instead of 1/4sqr stick and 6" sheets of 3/32" instead of the 2" sheets I had wanted to buy. But I am blessed with a real nice table saw ) A Delta 5000 series). So I installed my finest blade and went to rip city. Made lots of 1/4sqr sticks and 2" sheets of 3/32" for wing ribs. I then cross cut the 2" pieces into rib blanks. I will stack shape them in one or two stacks later.
I started building with the fuse sides. I did the first one sitting on the recliner sofa with my wife While streaming The New Yankee Workshop. I have a 4' balsa building board. Tools sitting on my laptop next to me. Dog booted from between mama's legs so I got room for the board. Wife's (Windy) tablet on her opposite leg.
So that got one side completely framed up, But that was not going to work beyond that. The second side was pinned right over the first half. Wide transparent tape was put over all of the joints so as not to end up with one double thick side. So for that I worked in the garage. Took a hour for my propane radiant heater to get the garage comfortable enough to work in.
Much of the forward section is spruce. There was no way the bottom spruce stick was going to make the curve. It got soaked in hot water. Then bent and left to dry before gluing. It goes from the firewall to the trailing edge of the wing, and the a 60 degree scarf joint to the balsa back half (epoxied). I found it was easier to over bend the hot wet spruce and let it dry that way. It then sprung back to very close to what I wanted. I was just guessing on how much to over bend it, but i got lucking first try, it really was close. Maybe just a bit over curve. But the vertical and diagonal sticks took care of that.
I, have made some so far minor changes to the structure. I added diagonals every vertical. All of the diagonals are mitered to the vertical and to the top and bottom longerons (correct term?). So there are two miters on each end of the diagonals. Tedious would be an understatement. The plans don't call for that many diagonals. And also I added gussets to every joint, even in between the diagonals. Even more gain tedious.
The gussets have been rounded out. I doubt it saves much weight but it sure does look way better, and they will be visible (transparent covering). Used my dremel tool with a sanding drum for that and a pair of rat tail rasps.
All the vertical spruce joints and the scarf joints are epoxied, the vertical balsa joints are Tightbond 2, and the diagonals are medium ca. All of the diagonals are balsa.
So far that is 4 build sessions. First session with my wife on the sofa, and the rest in the garage. Windy would have been out there with me if we could leave mom unattended for even a few minutes. But mom is 92, senile, virtually deaf and blind, and extremely frail now.
I moved my small disc sander right next to me in the garage. Sure made it a lot easier to fit the parts. And I am real fussy on how tight all of the joints are. Sometimes when the fit was just almost there but not exact, I spun the disc by hand vice turn the switch on so as to take an almost imperceptible amount off a gusset or vertical or the mitered diagonals. Maybe that is a bit anal. But i do believe that it does improve joint strength and beside all of the joints are going to be visible.
Ken