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My new plane

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My new plane

Post  oldguy on Mon Jun 25, 2018 12:09 am

Well I saw a picture a while back of a Quicker the .35 size.  So I started scratch building one, but a .15 size. I pickup a AP .15 and with the muffler on the rear, I thought it would be a good choice for it.
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Re: My new plane

Post  1/2A Nut on Mon Jun 25, 2018 1:38 am

Looks great good job on the build!! Thumbs Up
It should be fast. The muffler will need it's exhaust tip to the side so oil doesn't
collect in the muffler. Down being the best solution for complete oil drain.
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Re: My new plane

Post  balogh on Mon Jun 25, 2018 8:43 am

Looks great!! Please keep us posted on the build as it develops Smile
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Re: My new plane

Post  oldguy on Mon Jun 25, 2018 6:32 pm

Well this is it.


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Re: My new plane

Post  oldguy on Mon Jun 25, 2018 6:35 pm

1/2A Nut wrote:Looks great good job on the build!!  Thumbs Up
It should be fast. The muffler will need it's exhaust tip to the side so oil doesn't
collect in the muffler. Down being the best solution for complete oil drain.

Thanks for the comment.
The plane will be upside down half the time or more so I really don't see the exhaust pointing up being a problem. Only flying it will be the true test.

I have one question, where do you think I should start with the CG?
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Re: My new plane

Post  Ken Cook on Tue Jun 26, 2018 4:28 am

One thing that grabbed my attention is the tank, at least from the pictures it appears as if the engine is sitting on the beams and the tank is shimmed up considerably higher. This could really make the engine go lean when inverted vs upright. Unless you absolutely know where the height of the pickup tube is soldered within the tank I would just be aware to that situation and set the engine off slightly rich. Once you do a outside maneuver, it will become quickly evident if the tank height is set correct. Balance the plane where the front leadout exits the tip. This will almost always place your plane in a nose heavy condition and work from there removing it to make it more maneuverable. When the power cuts, examine the plane's glide path on it's return to the ground. If it's too nose heavy, remove the muffler because it robs about 1500 rpm's. It retains a lot of heat as well.
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Re: My new plane

Post  getback on Tue Jun 26, 2018 9:11 am

She looks really good oldguy , hope to see some fun in the air with it good luck with the maidin
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Re: My new plane

Post  oldguy on Tue Jun 26, 2018 1:52 pm

Ken Cook wrote:         One thing that grabbed my attention is the tank, at least from the pictures it appears as if the engine is sitting on the beams and the tank is shimmed up considerably higher. This could really make the engine go lean when inverted vs upright. Unless you absolutely know where the height of the pickup tube is soldered within the tank I would just be aware to that situation and set the engine off slightly rich. Once you do a outside maneuver, it will become quickly evident if the tank height is set correct. Balance the plane where the front leadout exits the tip. This will almost always place your plane in a nose heavy condition and work from there removing it to make it more maneuverable. When the power cuts, examine the plane's glide path on it's return to the ground.  If it's too nose heavy, remove the muffler because it robs about 1500 rpm's. It retains a lot of heat as well.

Yes Ken I shimmed the tank up some to align with spray bar, I didn't build the tank so I assumed the pickup tube runs straight back along the groove in the outside of the tank.  And yes with the first flight I will see if the height of the tank is going to work where it's at.   And I just checked the balance point and it balances just a tad aft of the front l/o.  So i'm assuming it will need some tail weight eventually.  so you have ran one of these ap .15?  Would you suggest I install just some sort of straight tube off the exhaust port in place of the muffler?

Thanks
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Re: My new plane

Post  oldguy on Tue Jun 26, 2018 2:00 pm

getback wrote:She looks really good oldguy , hope to see some fun in the air with it good luck with the maidin

thanks getback.
I hope to get to try and fly it soon.  I have a new R/M that I haven't had a chance to fly,  a Jr. Flight streak I have flown once that I have made adjustments to, and a new 1/2a size Voodoo shaped plane and then this plane, all scratch built.  The winds here have been blowing for the last month, plus we are under a fire restriction for lack of rain and it is so dry. Not allowed to fly. I will try and get video of them.
Thanks again.
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Re: My new plane

Post  Ken Cook on Tue Jun 26, 2018 3:16 pm

We tried the AP .15's for combat. They didn't offer the same power as the Norvel and the FP .15 were offering. I like them nonetheless. We then used them for some other racing events we were experimenting with. When we ran them, we took off the muffler and left the exhaust just exiting the case. We would RTV a piece of ply to the front of the tank smeared in it to prevent heat on the face of the tank.
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Re: My new plane

Post  oldguy on Tue Jun 26, 2018 3:21 pm

Ken Cook wrote:        We tried the AP .15's for combat. They didn't offer the same power as the Norvel and the FP .15 were offering. I like them nonetheless. We then used them for some other racing events we were experimenting with. When we ran them, we took off the muffler and left the exhaust just exiting the case. We would RTV a piece of ply to the front of the tank smeared in it to prevent heat on the face of the tank.

Thanks for that input. Also can you comment on how the AP .15 compares to the Fox .15?
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Re: My new plane

Post  Ken Cook on Tue Jun 26, 2018 6:33 pm

This is a tough question for me to answer. In addition, my use for the engine was solely combat which isn't the same as stunt or sport. The AP is ball bearing, the Fox .15 slant and steelfin aren't so there's going to be a considerable smoothness and rpm increase using the AP. The AP is also ABC which neither of the Fox's are and that in itself limits the Fox to really being pushed hard. What I can say about the FP and Norvel .15's were that we were seeing 20K plus rpm's using a 7x4. I even think we could've been using the APC 6.3x4 combat prop.  The AP was close but not 20. The Fox .15X isn't afraid of nitro.I don't see 20 K with the Fox.  I have run the engine on 50% nitro and it screams. I don't make a habit of it but I just love those engines and they just impress me for how archaic they really are. Your probably aware that there's a shim under the cylinder liner to decompress the .15X. That can be removed which can almost put 1600 rpm's to the engine. It might need a additional head gasket for piston baffle clearance if removed.

Phil Cartier of Core House products was using the AP engine for about 2 seasons. The crankshaft broke on his engine. The crankshaft diameter is small on this engine. In Phil's situation, this could've been a hard landing, it could also be a result of us running these hard. I never inspected or concluded a decision with the engine. I jumped on it due to the low cost true ABC construction and thought it would suffice for our events.

   It's quite difficult comparing old iron to new technology. I love them both and I favor the new stuff in terms of reliability but I love the old equally even though I might wear my arm out flipping them at times.
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Re: My new plane

Post  oldguy on Thu Jun 28, 2018 12:31 pm

Ken Cook wrote:This is a tough question for me to answer. In addition, my use for the engine was solely combat which isn't the same as stunt or sport.  The AP is ball bearing, the Fox .15 slant and steelfin aren't so there's going to be a considerable smoothness and rpm increase using the AP. The AP is also ABC which neither of the Fox's are and that in itself limits the Fox to really being pushed hard. What I can say about the FP and Norvel .15's were that we were seeing 20K plus rpm's using a 7x4. I even think we could've been using the APC 6.3x4 combat prop.  The AP was close but not 20. The Fox .15X isn't afraid of nitro.I don't see 20 K with the Fox.  I have run the engine on 50% nitro and it screams. I don't make a habit of it but I just love those engines and they just impress me for how archaic they really are. Your probably aware that there's a shim under the cylinder liner to decompress the .15X. That can be removed which can almost put 1600 rpm's to the engine. It might need a additional head gasket for piston baffle clearance if removed.

Phil Cartier of Core House products was using the AP engine for about 2 seasons. The crankshaft broke on his engine. The crankshaft diameter is small on this engine. In Phil's situation, this could've been a hard landing, it could also be a result of us running these hard. I never inspected or concluded a decision with the engine. I jumped on it due to the low cost true ABC construction and thought it would suffice for our events.

   It's quite difficult comparing old iron to new technology. I love them both and I favor the new stuff in terms of reliability but I love the old equally even though I might wear my arm out flipping them at times.
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Re: My new plane

Post  oldguy on Thu Jun 28, 2018 12:38 pm

Ken Cook wrote:This is a tough question for me to answer. In addition, my use for the engine was solely combat which isn't the same as stunt or sport.  The AP is ball bearing, the Fox .15 slant and steelfin aren't so there's going to be a considerable smoothness and rpm increase using the AP. The AP is also ABC which neither of the Fox's are and that in itself limits the Fox to really being pushed hard. What I can say about the FP and Norvel .15's were that we were seeing 20K plus rpm's using a 7x4. I even think we could've been using the APC 6.3x4 combat prop.  The AP was close but not 20. The Fox .15X isn't afraid of nitro.I don't see 20 K with the Fox.  I have run the engine on 50% nitro and it screams. I don't make a habit of it but I just love those engines and they just impress me for how archaic they really are. Your probably aware that there's a shim under the cylinder liner to decompress the .15X. That can be removed which can almost put 1600 rpm's to the engine. It might need a additional head gasket for piston baffle clearance if removed.

Phil Cartier of Core House products was using the AP engine for about 2 seasons. The crankshaft broke on his engine. The crankshaft diameter is small on this engine. In Phil's situation, this could've been a hard landing, it could also be a result of us running these hard. I never inspected or concluded a decision with the engine. I jumped on it due to the low cost true ABC construction and thought it would suffice for our events.

   It's quite difficult comparing old iron to new technology. I love them both and I favor the new stuff in terms of reliability but I love the old equally even though I might wear my arm out flipping them at times.

Ken I really didn't expect the Fox to be equal to the AP. Question I like to fly fast with my stunt planes and such, should I be using a 7x4 prop on my Fox's? Would the 7x4 be faster than a 8x4? What a 7x6 prop? You know I have a few 15x's and have had afew more in the past, I have never seen a shim under the cylinder liner. I quess the previous owners could have removed them. I run them on 25% nitro.
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Re: My new plane

Post  Ken Cook on Thu Jun 28, 2018 3:45 pm

Very good questions. I will start by saying I have never found the Fox's to be happy on a 8" prop period. Fox's like 7" props and if you have wood even better. If your using a 7x6 your going to have more speed but this is also going to taxi the engine in the maneuvers. If your hearing the engine sag a little in the maneuvers, then I would drop to a 7x5. There's nothing wrong with a 7x4 but I wouldn't use a G/F series 7x4 on a Fox due to a very thin blade area. Fine for newer Schneurle ported engines but the Fox likes a bit of a load which is true of most Fox's. Now if you have a older wider bladed 7x4 Master Airscrew all the better. Taipan 7" props work very well if you can source them. It comes down to experimenting and lending your ear to the engine and paying attention at or nearing 1/2 tank as the head pressure in the tank lessens and the engine leans out. This is about 2.5 minutes into the flight and the plane should be really going faster than when launched at this point.

Many of them have had that shimmed removed. I'm not even certain what years they were offered or always offered. I just know that I take them out. It's good to see that your using them. Many have formed such a negative opinion in regards to that engine.
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Re: My new plane

Post  oldguy on Thu Jun 28, 2018 5:37 pm

Ken Cook wrote:        Very good questions. I will start by saying I have never found the Fox's to be happy on a 8" prop period. Fox's like 7" props and if you have wood even better. If your using a 7x6 your going to have more speed but this is also going to taxi the engine in the maneuvers. If your hearing the engine sag a little in the maneuvers, then I would drop to a 7x5. There's nothing wrong with a 7x4 but I wouldn't use a G/F series 7x4 on a Fox due to a very thin blade area. Fine for newer Schneurle ported engines but the Fox likes a bit of a load which is true of most Fox's. Now if you have a older wider bladed 7x4 Master Airscrew all the better. Taipan 7" props work very well if you can source them. It comes down to experimenting and lending your ear to the engine and paying attention at or nearing 1/2 tank as the head pressure in the tank lessens and the engine leans out. This is about 2.5 minutes into the flight and the plane should be really  going faster than when launched at this point.

              Many of them have had that shimmed removed. I'm not even certain what years they were offered or always offered. I just know that I take them out. It's good to see that your using them. Many have formed such a negative opinion in regards to that engine.

I don't know why people don't like the little Fox .15 I have had nothing but good experiences with them, unless it's a totally worn out engine. One more question and I will leave ya alone for awhile. Why are the wood props better?
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Re: My new plane

Post  Ken Cook on Thu Jun 28, 2018 6:37 pm

Most of your older engines tend to do better with wood props. It's easier on the engine because they're lighter therefore the rpm's are a tad higher vs a heavier composite prop. I also strongly believe that the lighter prop not only keeps the CG aft, it allows the plane to turn quicker just because of the gyroscopic forces at work. The other thing is that most of the wood props are a bit lighter on pitch than what is printed on that prop. Rev-Ups for instance if you checked them with a pitch gauge usually come out a 1/2 pitch lighter than what is stated. These props tend to just let the engine run happy throughout the run. Newer props such as APC work very well because of their shape and the fact that their pitch is usually true. In this situation, it's better to drop a size in pitch when using them because it will absolutely load the engine when pushed into hard cornering maneuvers.
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Re: My new plane

Post  oldguy on Thu Jun 28, 2018 10:07 pm

Ken Cook wrote:       Most of your older engines tend to do better with wood props. It's easier on the engine because they're lighter therefore the rpm's are a tad higher vs a heavier composite prop. I also strongly believe that the lighter prop not only keeps the CG aft, it allows the plane to turn quicker just because of the gyroscopic forces at work.   The other thing is that most of the wood props are a bit lighter on pitch than what is printed on that prop. Rev-Ups for instance if you checked them with a pitch gauge usually come out a 1/2 pitch lighter than what is stated. These props tend to just let the engine run happy throughout the run. Newer props such as APC work very well because of their shape and the fact that their pitch is usually true. In this situation, it's better to drop a size in pitch when using them because it will absolutely load the engine when pushed into hard cornering maneuvers.

Thanks Ken
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