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Wildthing
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Cutting out my parts today getting ready to dry fit them
F35-B plans.

You will love the way that guy flies.

Just a foot note, most designers already have their official thread started so you really don't need to start a new one for every plane that way all the hints and tricks and builds are all in one place and easy to find. This is the last posting for the NAMC Mig-35B http://rcpowers.com/community/threads/namc-mig-35b-fulcrum-f.19069/page-97#post-286862 so I would start posting your build progress there.

Cheers
Jeff
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Butch1953
Tha
Quote:
You will love the way that guy flies.

Just a foot note, most designers already have their official thread started so you really don't need to start a new one for every plane that way all the hints and tricks and builds are all in one place and easy to find. This is the last posting for the NAMC Mig-35B http://rcpowers.com/community/threads/namc-mig-35b-fulcrum-f.19069/page-97#post-286862 so I would start posting your build progress there.

Cheers
Jeff

thanks sorry about that!
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TxTH
OK, so I am finally going to build the Mig 29 V5. I have had the plans printed out since way back in May of last year so I figured it was time. I don't get in a rush much since I retired a couple or three years ago.

So the first thing I did was trim the plans (printed large format at FedEx) and laid the first sheet out on my sheet of MPF and...oops, plans are for Depron.

So I have a question for you designers out there. I am too lazy to cut the plans apart and spread things out, plus I really want the wingplate to be a single piece. 27" vs 24" means I need to reduce the plans to 88.888% so they will fit my MPF. To make it simple I am going to print at 85% of the original. I know a lot of design work, testing, and analysis goes into these models so my question is, what happens when you reduce the size of plans like this to all of that testing and data. Are the expectations still pretty close to the same since I am only reducing them 15%? What should I expect when I take it out to fly, with the prescribed motor and electronics from the plans? Just curious. Thanks.
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SukhoiLover
You may need to reduce the overall weight, too, or end up with a faster plane (cruise, stall, landing, etc.). We tried that with an 80% F-15 V5 and it was a bit "hotter" than the 100% F-15 V5, but manageable. If you keep the battery size a little smaller (e.g., 1300 vs. 1800) you may be able to make it work out okay.

But keep ALL the weight down. I'd go with elevons only until you're more comfortable (less weight of servos, hinges, control rods, etc.). You can always add ailerons, rudders, etc. after you get used to the airplane.

I have seen some of the wizards in here reduce their airframes and get spectacular results. Alas, that is not me--but I'm sure some of them will respond, too, and share their magic.

One last bit. If you do make the wing plate two-piece but do a good glue/packing tape seam AND run carbon across the seam, I don't think you'll notice any reduction in strength.

Good luck and fly safely,

SL
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TxTH
Thanks SL. I had figured on the lighter weight and planned on using my 1300 batteries. I actually prefer to fly, for my style (crazy and erratic), with only two servos, usually set up in 4x4 mechanical with the ailerons. It's kind of like the turn signal on a lot of peoples cars, I never use the rudder anyway so why bother setting it up.

I don't usually mind the two part wing plate but just wanted to experience the simplicity of a one piece wing.

Some of the questions I was wondering about involved things like wing loading, stall speeds, etc. The smaller scale means smaller wing area, but also less weight so does the wing loading stay the same or is their some math curve involved when reducing things? Will the basics of the aerodynamic preformance be the same since the design is unaltered except for the size? I mean, none of it really matters other than my scientific curiosity because I will definitely build it and I know it will fly. I taught AP Computer Science for several years and I have always had a keen interest in how things work.

Thanks for your suggestions!
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SukhoiLover
If the wing loading is the same, the way the airplane flies that is BASED on wing loading should be very similar. I believe that the aerodynamics should be close, too, but there are some subtle things (airflow curves, control surface interactions, etc.) that may not quite "scale." But with the small differential you're talking about I do not think you're going to have any real adverse problems to solve. The designs seem to be quite flexible and forgiving.

Sometimes the weight reduction will not be equal to the size reduction (expressed as a percentage). For example, it is possible to end up with an airplane that is 88% size but 93% weight. As a starting point find out what the design wing loading on the 100% airplane is and use 88% of that (or less) as your build weight target.

Also, a smaller airframe going the exact same speed as a larger airframe will APPEAR to be moving faster because the human eye tends to judge speed of an object (at least in part) by how long it take to cover its own length. A Cassutt going 200 mph looks a LOT faster than a B-747 flying at 200 mph.

Hope that helps. Fly safely,

SL
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Wildthing
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Thanks SL. I had figured on the lighter weight and planned on using my 1300 batteries. I actually prefer to fly, for my style (crazy and erratic), with only two servos, usually set up in 4x4 mechanical with the ailerons. It's kind of like the turn signal on a lot of peoples cars, I never use the rudder anyway so why bother setting it up.

I don't usually mind the two part wing plate but just wanted to experience the simplicity of a one piece wing.

Some of the questions I was wondering about involved things like wing loading, stall speeds, etc. The smaller scale means smaller wing area, but also less weight so does the wing loading stay the same or is their some math curve involved when reducing things? Will the basics of the aerodynamic preformance be the same since the design is unaltered except for the size? I mean, none of it really matters other than my scientific curiosity because I will definitely build it and I know it will fly. I taught AP Computer Science for several years and I have always had a keen interest in how things work.

I think with only a 15% reduction you will be just fine even with a 1800 battery. It will probably come in a little hotter on landings but it should be quite a bit faster then the 100% one, that is with the same power setup, you may have to go down in prop size.


Thanks for your suggestions!

Quote:
Thanks SL. I had figured on the lighter weight and planned on using my 1300 batteries. I actually prefer to fly, for my style (crazy and erratic), with only two servos, usually set up in 4x4 mechanical with the ailerons. It's kind of like the turn signal on a lot of peoples cars, I never use the rudder anyway so why bother setting it up.

I don't usually mind the two part wing plate but just wanted to experience the simplicity of a one piece wing.

Some of the questions I was wondering about involved things like wing loading, stall speeds, etc. The smaller scale means smaller wing area, but also less weight so does the wing loading stay the same or is their some math curve involved when reducing things? Will the basics of the aerodynamic preformance be the same since the design is unaltered except for the size? I mean, none of it really matters other than my scientific curiosity because I will definitely build it and I know it will fly. I taught AP Computer Science for several years and I have always had a keen interest in how things work.

Thanks for your suggestions!
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TxTH
That all makes sense. I had heard about the 747 comparison many years ago and being reminded of that makes me understand how it relates even to the other models at the airfield. I know probably the biggest impact is that even though I am reducing the size and weight some, the power and thrust is not being reduced so that should translate into a faster and perhaps more responsive (sensitive) plane.
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Johan121264
My new Rcpowers  Mig 29 v5.1. IMG_20190329_180113.jpg  IMG_20190329_180044.jpg  IMG_20190329_180100.jpg   
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Wildthing
Johan121264 wrote:
My new Rcpowers  Mig 29 v5.1. IMG_20190329_180113.jpg  IMG_20190329_180044.jpg  IMG_20190329_180100.jpg   


Well done, that looks gorgeous 
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SukhoiLover
Can't get the MiG-29 v4 up and running, so I'm gonna leave this one right here . . .

I was a little timid about the MiG-29, with it being so fast and all. But I have to tell you it's a hoot! I've got a simple setup (elevons only, 2200 kV with a 700mA 3S) and it is great. Climbs really well, isn't too fast (yet!), and is a sweetheart to land. Don't know why I waited so long.

I also took advantage of the Corona Virus sale. The plans in here and at FRC Foamies are a deal on a regular day, but with half off they go from deal to steal. What's in your workshop?
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crshbandit
I want to try building one of your planes but I'm lost on how to get started. I have a good supply of depron foam but where do I start?
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Sidewayskiwi
crshbandit wrote:
I want to try building one of your planes but I'm lost on how to get started. I have a good supply of depron foam but where do I start?

Print off the plans , trim and tape together use a low tac style spray adhesive or glue stick and stick plans to foam 
Cut out mark scorelines with firmly pressed pen or pencil so marks transfer to foam 
Cut out parts remove paper template 
Tape reinforce opposite sides of score cuts ( control surfaces , fuselage , engine pods--anything that requires folding)
Wing platform is usually built first , then engine pods --fit servos etc as needed for access , fuselage then tails 
On RCPowers site there should still be "How To" vid logs etc
You will make mistakes we all do , just dive in and start learning
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