Hans K

I had made the wing to fit my ESM Spitfire, and the trailing edge did not fit this fuselage. The bottom of the fuselage needed 2 patches and some sanding.




I can not find any pictures from the different parts of the fairing, but here you can see that I made a bottom piece laying flat on the wing, and a second piece, curved on the broomstick, against the fuselage.




The full fairing.

Hans K

Before I finished the fairing, I thought it would be time to see if it would fly. So that is the video that I opened this thread with.




I made 4 flight that day, and it went great. I needed just a little trim but other than that it flew great. Stable and easy but a little slower than I wanted. I did not have enough ailerons to do a easy roll, but it was enough to make turns and keep it level. It landed nice and slow. Later I mixed in a little up with the flaps to land even slower. I also moved the aileron pushrods to the closest holes on the aileron horns and upped the rates a little bit. Now it is still rolls slow, but comfortably does a rol, even 2 in a row. I went to a slightly faster propeller, it still is not the fastest plane on the field, but goes a good scale speed. It flies good upside down. All in all, what more do you want. Well actually I want it to look like this.



I will start the finishing shortly I promise, but I want to fly it in the mean time.




So from now on this build is in real time.

alex5

the fairing is basically the fillet sliced at a very oblique angle,not quite perpendicular to the tangent of the same fillet,about 5 degrees off of 90.

Hans K

One side of the fairings finished and filled the other side prepped.




The other side also glued in place.

Hans K

Now it is time to start painting this thing. During construction I have used 2 different ways to prepare for this. On the wing I have used a mixture of baby power and water based polyurethane. It worked very well to smooth over nicks in the foam. I was very happy with the results. However after a while I got a lot of little cracks in the finish. I have sanded it several times, but new cracks seemed to show up after a while. I do not yet know what to do with that yet. So I used just water based urethane on the fuselage. That seemed to leave a nice hard surface area. I sanded and sanded and it became very smooth. From what I understood you could use spray paint over this surface without hurting the foam underneath it. Well that did not work out too well.




I think I sanded in some spots through the polyurethane and at the places where I layered pieces of foam there seemed to be areas of the glue that got really eaten up by the paint. So It will take a lot of filling to fix all the damage done by the paint.

Hans K

I sanded most of the silver paint off. I tried my hand at filling but with mixed results. A lot to the filler seemed to sand out, so I decided that I would just paint with latex paint and not be too fussy about the finish. I have spent enough time on it and I normally just want the plane to fly good no matter how it looks. I think next time I do this I will fiberglass the plane. The foam is too soft and gets dinged up too easy by it self.






So, Now the plane is just one shade away from white. I should have chosen something a little grayer, but the nice thing about a lighter color is that you see less of the imperfections.

Hans K

I also spent some time to prepare for the spinner. The top of the nose is a little too square for the spinner, so I glued some pieces of foam in the corners.




Now the nose is nice and round and the spinner fits nicely. I am going to fly this morning, but I did not put the spinner on. I want to wait with that till I have the mufflers in place. I am planning to make them hollow, so I would get some air to the motor. I do not know how I will do that but that is the plan. The motor gets very warm, so I am worried to put the spinner on.

Hans K

I have a projector. I put some photo's on a USB stick and projected it on the fuselage. It took a bit of arranging to get everything lining up. But it made it look real good.


490

Then with little pieces of “Frog tape” I went around the lettering and the flag on the tail.




Unfortunately the frog tape did not do so good.




So the other side I just marked out the flag and the roundel.




I free handed the left flag and both roundels. It is not perfect, but it is better than the tape. Now I have to find a way to do the letters.

Hans K

By the way, all this painting is putting the C.G. further back. It is still acceptable, but it is a little more touchy. Yesterday I flew 4 times, the 2[SUP]nd[/SUP] landing I almost stalled and the last landing I nosed over in the end. I touched down just fine, but hit something in the runway. The plane wanted to nose over, so I pulled elevator. Too much, the plane came of the ground, I gave a little throttle the plane settled back, but with the tail high, and nosed over. I will put some fiberglass on the nose to make this stronger, and more resistant to scrapes. It will also help the C.G. I was happy the spinner was not on!

gerritkuhne

Looks Great!

Hans K

I have done very little on the spitfire this week other then flying. I fixed the nose from the nose over and prepared the prop further for the spinner.. I also played with options for the exhaust stacks. Someone from the hobby barn gave me a canopy. It is a little too small but I put it on any way. This way it looks a little more finished, and people at the field are bugging me about it.


Some fiberglass on the nose. It is also painted.


I had a hard time tightening up the propeller, it would slip at the last bit of tightening. It is always a problem putting on the spinner if you can not hold the motor. I used the prop adapter to drill 3 tiny holes in the prop, 1/4” deep. Then I put 3 pieces of piano wire in them. These pieces of wire fall into the heads of the allen screws of the prop adapter. I assume that the prop manufacturer will not support my way of doing this, but I hope that it will not affect the hub of the prop too bad.

Hans K

This is how it looks at the moment. As you can see I nosed over after the fiberglass.

Hans K

Yesterday I put the blisters on the top of the wing and did some paint work. Unfortunately the cracking that happened from the mixing of the water based urethane with baby powder really shows up.






But after 2 coats and if you stand back It looks not too bad. I will have to sand some more and paint some more.

Hans K

Today I put in the exhaust stacks.




They are made over a balsa mold out of heat shrink. Light quick and easy.



The Brian Tayler plans had the rounding of the cowling around the stacks on the top. This is clearly different on this spitfire.

The stacks are open to let air move out from around the motor. Later I will make the air intake also functional and hope that in that way I will keep the motor cool enough. It gets pretty warm without the spinner, so I need all I can get.

gerritkuhne

I think it looks great!

Hans K

I just notice that the Brian tayler plans had the rounding of the cowling around the stacks the right way. I must have screwed it up somehow.

Hans K

Someone at the field claimed that if the spinner was metal it would function as a heat sink so the motor might be not as hot as I would expect. So I tried this out and put the spinner on. The spinner still needs to be painted but it looks good just shiny.


I drilled 3 little holes in the spinner back plate to accommodate the 3 little pins in the propeller with the help of the propadapter. With 3 little pieces of piano wire that fall in the allen head screws the propeller doesn't spin while you tighten it up.



So I flew with it this way, and the temperature was not too bad. It used to be under 150° F while flying, and creeping up to 165°F after. The 3[SUP]rd[/SUP] flight was the warmest. The Temperature got to 165°F while flying and 10 degrees warmer after.

Hans K

To keep the temperature as low as possible I made the Air intake scoop functional. I do not know how good it works, but every bit helps.



The intake is open and on top of the battery hatch now has a duct on it so the air gets moved to the front. It seems to take about 10 degrees of the temperature while flying. It stays at 152-155°F. But it still wants to get too warm just after flying. It got to 177°F after the, that is too close to 180. It was close to 100°F outside, and a short while after the 3[SUP]rd[/SUP] flight. I might have to cut a hole in the front of the plane, under the propeller. I was hoping to prevent this.

Hans K

I flew again yesterday, and someone suggested to fly slow just before landing. I tried this out and it made a huge difference. Here is the log file. Isn't the Taranis transmitter wonderfull!



As you can see, I started out at 86° F (green line), The max temperature was 150° F flying full throttle (red line). I droped the throttle to about ½.. The wattage drops then to about 250 watt (blue line), and the temperature starts dropping almost immediately. After 1½ minutes I land with a temperature of 128° F, and then creeps up to 142° F. That is a very acceptable temperature. It might not be the ideal way to keep the temperature down, but not a very bad way either. I do not have to cut a hole in the nose.
The All Up Weight has been creeping up. At the first flight it was 11.5 Lbs 5,2Kg. Now it is 12.6 Lbs 5,7 Kg. That is more than a pound in the spinner and paint, and I am not finished!

Hans K

I flew again yesterday, and someone suggested to fly slow just before landing. I tried this out and it made a huge difference. Here is the log file.



As you can see, I started out at 86° F (green line), The max temperature was 150° F flying full throttle (red line). I droped the throttle to about ½.. The wattage drops then to about 250 watt (blue line), and the temperature starts dropping almost immediately. After 1½ minutes I land with a temperature of 128° F, and then creeps up to 142° F. That is a very acceptable temperature. It might not be the ideal way to keep the temperature down, but not a very bad way either. I do not have to cut a hole in the nose.

Hans K

Now I was working on the Hispano Cannons. I decided to try to make them out of Heat shrink. First I made a 3/4” dowel in the shape of the cannon on my elaborate lath.


A piece of heat shrink on the front an d back, then one over the whole thing, and this is the result.

Hans K

I found an other 72inch spitfire out of 1/4" foam. http://www.rcgroups.com/forums/showthread.php?t=1592598
This one is also lighter than mine! Good job eflightray. It looks and flies great.

Ram-bro

My Feedback: (101)

Might have to try this.

Hans K

Try it, it is not as difficult as the results make it look.

sidgates

My Feedback: (2)

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I am always interested in alternate building methods. This one is intriguing but looks time consuming. I am building a 3 Axis CNC router which I plan to try out cutting the inside of a foam fuselage first. Then applying a thin glass cloth, add bulkheads for stiffness if needed then flip the block over and cut the outside shape. Next glue the two fuse halves together. Then cover the outside with glass cloth. If any one has tried this I would like to hear from them.
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