GP Stuka A.R.F. build
07-08-2005, 07:27 AM
#27
RE: GP Stuka A.R.F. build
The cowl is done! I used Rustoleum primer and Sunburst Yellow. The primer said it was for automobile use also. USE THE PRIMER! I sprayed it, waited 4 hours, and sanded it (next time I would wait over night). It sanded really smooth and the primer was like a glass shell. I started with 260 grit and finished with 400...LIGHTLY! Then put on about three thin coats of paint. Make sure you sand down the paint lines before the primer between the black and the green or they will leave lines like in the first photo.
07-08-2005, 06:36 PM
#31
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RE: GP Stuka A.R.F. build
Wheel pants are too much trouble on our grass field. Its just too rough in spots and they catch and poke backwards so I don't install pants any more. I hope bending the gear forward hasn't screwed up the pants installation for you?!?[
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07-10-2005, 10:52 PM
#32
RE: GP Stuka A.R.F. build
TAKE YOUR PANTS OFF! Not literally but on the grass field on the first flight I had an engine out and had to do some unusual attitude flying to get her to the runway and I landed on the threshold and a little sideways and one of the pants got a little damaged so I took them off.
This thing flies excellent. If anyone is past the trainer stage and had a couple other planes, low wing or such, this would be a good start into warbirds. I will try to get some video next time. First take off run was a little ruff but by the third I ran it along the runway for a while to see how it tracks and it was excellent. After the tail comes up just fly it with the rudder and when you get ready just pull back a little and it is smooth! The engine gave me a lot of problems though. I tuned it a couple days ago but then I put a Dubro exhaust extension on it and I think it messed up my settings.
All I can say about the JR 9303 is AWESOME! The flaps take a full 4 seconds to come down. At first I had them linked with the elevator and had too much down elevator which was almost desasterous. When the elevator is linked with the flaps they both move at the same slow speed (unless you give the elevator some other movement).
I need to explain that the remote glow is NOT because the engine is at a 45 degree down, it's just because I had it, I like tinkering, and thought it would be fun and since I'm still new to tuning engines I came in real handy not to have to search for my ignitor.
When you set up the plane initially go with 60% on the off side of the dual rates if you have them. The books recomendation is WAY to much for me right now. But then again I may have made a mistake when I set them up.
The third landing was equally as good as the takeoff run. I used half flaps which helped slow the plane down since the engine was idleing too high and the landing was good, not great yet but good.
I had some bumpy landings the first two times but besides the wheel pants it took it great. It was nothing like what I read about in the Warbird colum with all of the damaged landing gear.
This thing flies excellent. If anyone is past the trainer stage and had a couple other planes, low wing or such, this would be a good start into warbirds. I will try to get some video next time. First take off run was a little ruff but by the third I ran it along the runway for a while to see how it tracks and it was excellent. After the tail comes up just fly it with the rudder and when you get ready just pull back a little and it is smooth! The engine gave me a lot of problems though. I tuned it a couple days ago but then I put a Dubro exhaust extension on it and I think it messed up my settings.
All I can say about the JR 9303 is AWESOME! The flaps take a full 4 seconds to come down. At first I had them linked with the elevator and had too much down elevator which was almost desasterous. When the elevator is linked with the flaps they both move at the same slow speed (unless you give the elevator some other movement).
I need to explain that the remote glow is NOT because the engine is at a 45 degree down, it's just because I had it, I like tinkering, and thought it would be fun and since I'm still new to tuning engines I came in real handy not to have to search for my ignitor.
When you set up the plane initially go with 60% on the off side of the dual rates if you have them. The books recomendation is WAY to much for me right now. But then again I may have made a mistake when I set them up.
The third landing was equally as good as the takeoff run. I used half flaps which helped slow the plane down since the engine was idleing too high and the landing was good, not great yet but good.
I had some bumpy landings the first two times but besides the wheel pants it took it great. It was nothing like what I read about in the Warbird colum with all of the damaged landing gear.
07-10-2005, 11:23 PM
#34
RE: GP Stuka A.R.F. build
Here is the remote glow device I made. It's a micro servo that pushes a small arm switch to turn on the glow when the throttle is below 20%. The 9303 is able to slave another channel, I used Aux. 4, and still be able to use the switch for that channel (although it's not recommended because it could be undesirable) or inhibit it. In my case when it was turned on it allowed the servo to press the switch when the throttle was lowered but when I turn the switch off it will move the servo arm about 90 degrees in the other direction so it can't trigger the glow...so it's an on off switch. I also mounted another slide switch next to the MPI battery checker/charger to turn off any power getting to it. Because of this extra weight and (mostly) the engine I used I had to add 10 pieces of weight to the tail. It's on the outside now but I'll epoxy or CA it inside after I make a hatch to access it incase I change engines later.
I don't know what's wrong with this engine, it likes to run fine out of the cowl...maybe it's closter phobic? I should be able to tinker with it till I get it right this week, may have to remove cowl again or put a larger exhaust deflector on.
I don't know what's wrong with this engine, it likes to run fine out of the cowl...maybe it's closter phobic? I should be able to tinker with it till I get it right this week, may have to remove cowl again or put a larger exhaust deflector on.
07-10-2005, 11:28 PM
#35
RE: GP Stuka A.R.F. build
Warbirds can be turned perpendicular to the ground really quick so try to square off your landing pattern to give you some room. If you got use to flying in close I wouldn't because unless you are comfortable turning a plane perpendicular it's really scary. It wasn't until the thrid flight that I felt a little comfortable with this but my flights were short because of the engine. I flew for maybe 10 minutes total but it was great. I was so nervous I had to ask my wife how it looked because I was just trying to fly.
07-11-2005, 08:09 AM
#36
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RE: GP Stuka A.R.F. build
Glad to hear that you are enjoying the plane! The road to our field got flooded out and I haven't been able to fly for about 3 weeks now.[]
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07-11-2005, 09:19 AM
#37
RE: GP Stuka A.R.F. build
Although I haven't flown that much with it, it did seem to have a problem pitching up when I added throttle. I also noticed the engine is pitched up. Have you experienced this? Once I get the engine tuned I can fly a little longer to see what's up.
07-11-2005, 12:38 PM
#38
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RE: GP Stuka A.R.F. build
I haven't noticed any pitching up with throttle problems my self. Never checked the angle of the engine. Jst bolted it on and took it to the field. [8D]
07-11-2005, 03:08 PM
#39
RE: GP Stuka A.R.F. build
I'll get it tuned up so I can fly longer than it takes to trim it out[:@]and maybe it will be fine...thanks!
Has anyone had any heating problems? The engine sticks out enough that the head fins are out of the cowl but not the cylinder body...'maybe over thinking it though.
Has anyone had any heating problems? The engine sticks out enough that the head fins are out of the cowl but not the cylinder body...'maybe over thinking it though.
07-12-2005, 02:10 PM
#40
RE: GP Stuka A.R.F. build
I asked the alignment question to Hobbico and they sent back the location of the data. It is suppose to be 2 degrees down and two to the right too so I'll re-shim it this week. I'll take a picture of it from a distance from the side and put it on CAD so I can determine how far it is out. I just got a new carb for the ST because, through the engine forum, we figured out the needle valve assembly has some issues and I didn't know if it's the housing or the assembly so for $34-no guessing!
07-12-2005, 03:39 PM
#41
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RE: GP Stuka A.R.F. build
The instructors at our field curse to themselves when they see a new flyer looking for help and there is an ST engine on the front of the plane. It seems you spend a lot of time trying to get the engine to run great. Then you do the takeoff, make the first turn and blaaat, the engine suddenly quits! The carb barrel also tends to suddenly jam in in 1 position. I also had this happen on another brand. Now I remove the carb barrels on all my new engines and check for rough spots. OS is an exception, the barrels are super smooth, never a problem. 
07-12-2005, 04:02 PM
#42
RE: GP Stuka A.R.F. build
It seems everyone fears the unknown. I know a lot of people that swears by them but there are those that swear at them. I found out I was adjusting the wrong screw! The carb seems worn around the needle valve assembly so I bought a new one at lunch and this time I'll screw with the right setting. Like I said, it ran fine out of the plane but I know I messed with the idle screw during installation...thanks. I'll let you know how it runs after I change the bad carb out (I didn't know if the needle assembly was loose because of the carb housing or if the brass insert was worn so it's getting a new one - that's were I found I was adjusting the wrong one, I looked at the instuctions).[:@]
07-19-2005, 11:46 PM
#43
RE: GP Stuka A.R.F. build
Ok, now I'm swearing at the ST! I get it running smooth on the ground, flies good for 5 minutes and then starts to crap out. I retune it, it flies for a while and starts running poorly. I'm sure some of it is my abilities, some from the engine might have some internal issues, there might be a over heating problem because covering some of the extra holes in the front seems to help (it has more opennings in the front than the back as far as volume). Anyway I made a deal on a new Saito 91 for a really good deal and I'm thinking I'll mount it wholey inside the cowl inverted so I don't have to cut extra holes.
As far as the mounting, you will probably have to add an extra (thick= 1mm) washer under the top to increase down thrust because this helped a lot with mine.
It has much better glide than I expected from a war bird but you can not float it in on a dead stick. Keep the throttle up till about 1 foot above the ground and flare and let the ground effect settle it in and it lands beautiful.
I'll add the motor and do final photos later. (I'll try to do some video if I can get a capture card).
As far as the mounting, you will probably have to add an extra (thick= 1mm) washer under the top to increase down thrust because this helped a lot with mine.
It has much better glide than I expected from a war bird but you can not float it in on a dead stick. Keep the throttle up till about 1 foot above the ground and flare and let the ground effect settle it in and it lands beautiful.
I'll add the motor and do final photos later. (I'll try to do some video if I can get a capture card).
07-25-2005, 02:48 PM
#44
RE: GP Stuka A.R.F. build
I got the Saito 91 mounted and this time I went with a 15 degree from down or 255 degrees. This put the air flow completely away from the engine so I wanted to dam up the scoop but didn't want a straight piece so I fabricated another one. I skipped the microballons -big mistake- because I didn't want it to be too heavy (the procedure is not that heavy but I was counting grams because I hate adding weight) but I was able to take all of the weights off the tail and now I need nose weight. I didn't know the ST was that much heavier than the Saito but it sure sounds sweet. I think I'll always try to put a four stroke in from the beginning.
07-25-2005, 09:10 PM
#45
RE: GP Stuka A.R.F. build
Pitching up problem solved...now with the Saito I can fly around more than 2 times around the pattern before the engine dies. The problem is that it flies with a little down elevator. With this it doesn't pitch abnormally when the power is changed but I will still add another washer on the top two mounting holes behind the mount.
07-28-2005, 10:44 PM
#46
RE: GP Stuka A.R.F. build
Finished the new cowl. It looks a lot better and cooling should be better. I flew with the new engine last week and tomorrow I'll fly it with the new cowl and hopefully I'll get the decals on next week. The extra hole on the right side of the picture is for the exhaust.
08-17-2005, 11:21 PM
#47
RE: GP Stuka A.R.F. build
Ok, final post. It flies great! After getting it dialed in it is very predictable and easy to fly. I was wrong about the angle of the fire wall, it does not need to be tilted. It is a not a fast war bird but it isn't slow either. If you use the Saito 100 and keep the battery foward you may not have to add any weight and it can be flown out of some low airspeed take offs without stalling. I've come close to this on occation with the Saito 91 and it was fine. It's not as forgiving as a trainer but it is no where as unforgiving as a war bird.
It is a favorite everywhere I go but I would suggest the two modifications I did: aileron servo hatches were easy and will come in handy but the cowl works excellent and the cooling is much better but not necessary.
If you are planning on your second plane and plan to fly war birds start with this one. If you have some different low wing models under your belt with some speed you might want a P-47 or Sea Fury.
Happy Flying!
It is a favorite everywhere I go but I would suggest the two modifications I did: aileron servo hatches were easy and will come in handy but the cowl works excellent and the cooling is much better but not necessary.
If you are planning on your second plane and plan to fly war birds start with this one. If you have some different low wing models under your belt with some speed you might want a P-47 or Sea Fury.
Happy Flying!
08-18-2005, 09:05 PM
#49
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RE: GP Stuka A.R.F. build
rangerman have you figured out what to do about the whistle?....i just picked up a GP stuka in good condition with 4 servos for $60..i'm thinking about putting a YS 1.10 with a 3 blade prop
08-18-2005, 10:12 PM
#50
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RE: GP Stuka A.R.F. build
txaggie08, the Stuka would make a great first warbird! If you have some bottom wing experience the plane shouldn't give you any problems. I also have a Zero and a Sea Fury. They aren't hard to fly but they are more tricky than the Stuka and both land faster by quite a bit. When you join the prebuilt wing sections of the Stuka the result is the wing has a fair bit of dihedral. This means that the plane is quite stable and acts like a trainer in that if you let go of the sticks the plane will self level like a trainer. The plane is also easy to takeoff and land. Only problem you might have is finding one. I read that they aren't making the plane any more. []
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