building 120" Don Smith Corsair from Kitcutters
 

Kitcutters now has a short kit for Don Smith Corsair 120" and I have the first kit

I don't know if this is the place to start a build log for the Don Smith 120" Corsair but I am sure someone will tell me. I am Gary Sorensen and I have been flying RC sense the late 70's
In the early years most built from plans or kits. I can't tell you how many planes I built but in the 80's my first wife told me I was spending too much. In 1996 I was taking flying lessons in a 152 Cessna and some how I found out about Oshkosh. That year I went and then decided I could build a real airplane. It looked just like building a model to me. On the 2 year going to Oshkosh I arranged to test fly some of the factory planes. I flew a 3 different company planes and decided on a Lancair ES and if you google n1169g you will find I did it. I had to sell it in 2003 do to loss of income. I built that plane in 4 years and did it all myself. As for models I have spent more than 150K over the years on them. I am a flight ip instructor, leader-education, leader-flight,turbine-fixed, and contest director with AMA. I am now 68 and want to build this Corsair to maybe be the last plane I build. I have no intentions on making it a contest entrant. I just like big planes.
Let me start I have the plans and I was able to get KitCutters cut a short kit. So now I am the test builder for the short kit and the plans that Don Smith made.
I am starting with the center section of the wing as it will be the hardest to do.
I have epoxied the 3 wing braces together I use West epoxy with fast hardener. I know this epoxy and I have the best results with it.
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wing braces
I then put the wing ribs in there slots but not glued.
I come to find I had to make some slots longer as they were not cut enough. By the way I am in touch with Kitcutters and tell them things I would change.
I also found there is no passage way for wiring or air lines. I will be doing that shortly . I looked at this for a long time and decided that the wing spars will need to be pre bent or it will be very hard to put in place without putting stress in the wing.
I took the wing brace ant traced the shape on a piece of 3/4" ply and took a 1" pvc pipe and caped the bottom and put 2 of the 3/8" X 1/4" spars in side with hot water and let soak for 1 hour the clamped on the top of the brace. I will do the same on the bottom and on the top and bottom of the rear brace.
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Then I looked at the plans and noticed the main spar does not go all the way to the end so for the last three ribs it just has the top and bottom wing spar and 1/32 ply to the back of the spar.
In this section has the wing tube. To me that's not right the spar should go to the end. When I traced the rib on the plywood I extended it out to the end of the wing at rib 12 I know I will have to slot the 10 ,11,12 ribs to fit
I want to have a strong plane and just did not seem right to be weak in the area for the wing tube.
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I sill work full time so I will be doing more later.
n1169g is online now Report Post Today I had a little time to work on wing. I made lighting holes in the ribs and a 3/4" hole near the back for a path for servo wiring . I found thin wall hose at Lowes to use for conduit. As you can see I made a 1/8" ply extension to the main spar this will take it to the end of the wing like I suggested earlier. I CA the ribs starting at the center on the main spar and worked my way out. I did it with the wing sitting on top of the front spar to keep it straight. the wing as it is shaped putting it over the plan's won't work. It came out well rib #5 needs some adjustment I believe it is a mistake in the rib drawing. I will let Kitcutters know to correct. Also rib 6 and 7 need to have the wheel wells cut in. the plans only show it on rib 7 but the wing drawing shows it in 6 also. I am glad I pre bent the spars. they did not stay full shaped but it was easy to put in place than if I didn't . I did install the main bottom spar.
Now I am as far as I can go on the wing till I get the wing pole that I ordered and the retracts that I ordered from Carf. I want the tube in place before I glue the rest of the ribs in.
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Sense I am waiting on the wing pole to get here I am making the left wing panel today. The attached photos show you how I have done it so far today. The brown glue is west epoxy with fast hardener.
I did use 1/8" light ply for the web's I did not have any 1
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/32 ply here. Remember to put the grain up and down. remember to apply glue to both sides for the best results. The slots for the wing spar are good and snug fit again thanks to Kitcutters for the great job.
I also added a 3/8 sq balsa to the leading edge to give it more support to the ribs.
n1169g is online now Report Post

I have been having delays getting some needed parts in. But I did get the main retracts in from Seara . I have been working on that part. I did have to cut out ribs 6 and 7 as the angle and spacing was not going to let me get them in. I made new ribs and mounted them straight in the wing with 1/2X 3/4 rails . The Seara are quite large but very well made. I am sure this is the right gear for this plane. I am still waiting for the wing pole. the wrong one was sent and I am waiting for the replacement so I can finish the outer ribs.
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I am still waiting for the wing tubes to come in I hope next week. I had some free time from work so I started the body. The plans show to make it half at a time . I have never liked that method so you will see that I put the half's together and build a jig to hold them in the required locations.I find this way it comes out very straight.
the parts are not glued in yet. I like to check the fit with it all together before I glue them in. Harbor Freight had the c clamps on sale last week.
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First I marked the ribs on 1" angle then screwed the angle to my building board
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I then screwed more angle at each rib location. on the plans always the center line is even with the bottom of the plans. I measured from the bottom of the plans to the bottom of the rib and clamped in place
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next week I should get the tail wheel retract so I can fit it then I will start gluing

The tail wheel retract made me glad I have not glued the fuse yet. I took out F13 and made a mount for the retract. The retract came without a way to mount the air cylinder to the unit. i took two pieces of alum angle and mounted it to the frame of the retract so it would be able to come out in one piece.
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I will have more photos and text after the holidays. I hope you all have a good Christmas

I have been working on the elevator section some. I found the ribs are at full length and must be cut for installation
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I did it in 2 half as the plans suggest.
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I installed the servo wire before closing
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I put a old carbon wing tube in for wire and air line to the tail
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I am now starting to plank the fuse. I found that Velcro straps help hold it to shape. Getting CA to hold balsa to ply hard to do so I am using epoxy slow set. It takes longer but I know it will hold.

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The engine has arrived. More incentive

I am trying to get back to the progect but I have to help my son finish his first so he can fly this year. I have picked at it wile he is working on his .
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