I managed to get done what I hope will be a series of useful diagrams/pictures and supporting info on my latest Mig29 V4 NAMCV3 build. It is an ambitious set of modifications, so the diagrams may seem a little busy and complicated at times, but I hope they are usable if you want to duplicate them.
Since one of my main goals in this project was to morph the Mig29 into a Mig35, I used this diagram of the Mig35 for reference for my wing and elevons since I had to free hand draw the curves somewhat.
I will start at the rear of the plane and move forward. I drew my mods on a set of untiled plans from the print shop but they should work on tiled or untiled plans. If you right click on any of the photos in this post, you can save them so that you can enlarge them at your convenience, or if you e-mail me at migsrus@outlook.com I can email them all to you.
Elevon/back plate mods
Unfortunately I am not that computer gifted, I tried to make a template that might be usable for you to print off and lay over the stock plans, but that did not work as well as I would have hoped... :/
Edit 01 November
I added this picture of a tracing of my NAMCV3 elevon mod that I scanned into my computer. Perhaps if you are more technically gifted than I (which is very highly likely... :) ) you can make it work for you. When re-sizing and printing the picture, it is important to ensure your hinge ling measures as close as possible to the 6 and 13/16" as shown in the picture.
This first picture shows in yellow the modified elevon, hopefully you can follow all the measurements and angles. For the two corners at the tip of the elevon I hand drew in the curves using the diagram above as a reference. What I might recommend is to print off the pages you need from the tiled plans, do the drawing on that, make yourself a template from some scrap foam or cardboard to ensure you have it shaped the way you like and then trace that on your final plans to ensure everything lines up OK. This is an extra step, but will allow you to do what changes you need before cutting out your final parts for your build which should hopefully save you some foam and frustration... :/.
This second picture shows that I moved the tab on the side of the back plate back 1" since I am going to be moving the back part of the fuselage forward by 1" and I also like to move the back of the prop slot to the rear. I didn't draw in how I like the rear of my prop slot to go, I'll leave that to you. Mine is a pretty big hole in the middle of my plane, but when I put the NTM motor on my plane, the prop will be moving back about 5/8" from where it is with the Focal Price motor, so I wanted the extra room in my prop slot.
There is a lot going on on the whole rudder/vert stab/side fuselage/nacelles intake piece, this piece shown below. It might be easiest to print off the tiled plans to do all your drawing and reconnecting before cutting the final pieces out. I made a template out of scrap dollar store foam and then laid it over the plans before cutting out my final pieces.
I found it easier to do this whole piece in steps, starting with whatever vert stab/rudder mod you want to do.
Vertical stab/rudder
To accommodate the type of rudder style that I like and to make it look more "Mig35ish" which was my goal, I went with the same rudder and vertical stab setup I used on my Mig29 NAMCV2. You can use whatever rudder size you like, but if you want it to look "Mig35ish", I would keep the outer dimensions and angles of the trailing edge of the rudder and the vertical stabilizer. The black "squiggly" lines are of no use to the mods, just to divide the different mod areas up on my diagram to denote the different sections as there are essentially three mods on the same piece of this plane. I found it easiest to do all this drawing first before moving onto the next step of shortening the rear fuselage.
Shortening rear fuselage
This is a pretty busy picture with lots going on, so I broke it down into three steps to hopefully make it easier to follow.
Step 1
Measure and cut out the area outlined in orange. This needs to be taken out to accommodate moving the motor further forward by 1" and shortening the rear fuselage by 1".
Step 2
Measure and cut out the area outlined in yellow. Do not cut out/off the area marked with the * as leaving that there will make it easier to line things up and tape them together in step 3.
Step 3
Line up and tape line A to line B, this will then shorten your rear fuselage by 1"
I didn't make this a step, but you will note at the bottom of the picture, you will need to move the tab on that inner part of the nacelle forward by 1/2".
Curved/"ski tip" front of intake mod
This is an optional mod depending on what you like, I found from my first 10 flights it makes landing much less abrupt as the front of the intake does not dig into the ground. Once you measure out the angled parts as shown, you will want to move the leading edge of the middle part forward to ensure that it is long enough when you bend it forward to make the "ski tip".
Wing/aileron mod
I made these mods to give it the "Mig35ish" look. If you look at the diagram at the very start of the post, you will note that the wing on the Mig35 is kind of "F15ish" where the wing is 90 degrees to the fuse for the first bit, then it angles back slightly and the tip is slightly curved. The inside edge of the aileron starts 3/4" from the wing root to accommodate running the elevon pushrod on the outside of the fuselage. You may have to kind of free hand the curved wing tip, I extended the tip out by 1/4" at the centre of the tip and then curved it gently back into the leading and trailing edges. Again, you can use my drawing below or the Mig35 plan view above as a guideline.
KF Airfoil mod
I used KF4s (top and bottom) on my Mig29 which is what I would recommend for best speed and stability. Because I altered the wing shape somewhat, I moved the trailing edge back to make it approximately 40% of the wing chord which I find works the best on the Mig. How I did this was I extended the trailing edge back 7/16" at the root and 1/4" back at the tip. You will also want to ensure you trace the curved portion and slightly extended wing tip on your new "Mig35ish" wing. You can do this by laying the wing plate over the KF and then just trace it before you cut the KF out of the paper. The drawing on the plans is quite confusing in my opinion. Where it is labeled "KF4 airfoil (optional)" and "KF2 airfoil (optional)" should be reversed. The large piece including the portion that covers the leading edge extension goes on the top (KF2). Then if you use KF4, you cut out the smaller airfoil using the dashed line for reference.
What I like to do is make one of the KF2 airfoils, dry fit it, then use that as the template to make my second KF2 airfoil. Once I am happy with those, I then cut along the dashed line, ensuring I continue the long dashed line all the way back to my new trailing edge, then use that as the template for my bottom (KF4) two airfoils. Hope I haven't made this too confusing. The important thing about KFs is to ensure the wingtips are uniform, therefore the trailing edges should be equal as well.
Motor mount mods
In order to move the motor 1" forward, you will need to move the front of the prop slot and motor mount area all forward by 1". It might be hard to see as on the plans the dark line where they suggest the wing spar goes covers up where the new front of the prop slot will be, but hopefully you get the idea. You will also note that I moved the two slots that accommodate the tabs from the inner part of nacelles 1/2" further forward so you have a good solid gluing area.
Since the area then gets a bit tight for space to put in your carbon fibre wing spar, I ended up putting my spar across the two slots as you can see below. I then had to cut little notches in the tabs that go into them, but it worked out well and there is no loss of structural integrity.
In the picture below, I show adding about 5mm to the top of what will be the back of the motor mount. The reason being (I found this out the hard way... :/) is because you are shortening the back of the front fuselage, the angle is different so when you put the battery hatch door down, there is a pretty good gap between the hatch door and this piece where you would put your magnets to secure the door. I ended up gluing a scrap piece of dollar store foam on the top of mine to make it all work, so I put this in as a mod so you can modify it before putting into the plane then if you find it too high, you can shave it down a bit.
Shortening front fuselage
Since you will be moving the motor mount forward by an inch, you need to shorten the front fuselage accordingly. You can see how I moved everything (including the slots where the fuse slides onto the wing plate) by 1". These are how the pieces are laid out on the untiled plans, you need to do that large fuselage piece as well as the top piece that is the top of the fuselage.
Nose former/bulkhead mod
Depending on how you lay out your components, you may or may not need to worry about this mod to have the extra room in the electronics bay, but if it means lightening the plane up a bit without compromising structural integrity, why not? :)
So if you choose to do this mod, you will want to move the three slots that accept the tabs on the bulkhead forward by 1" as well as the rectangular air vent so that you have more room to apply Velcro. I made what will be the side slots for the bulkhead a bit shorter so that I didn't have such a thin bit of foam between the bottom of that slot and the slot that accepts the tab from the front of the leading edge extension (LERX) of the wing plate.
Then I just measured and cut 1" off the back of the nose former piece.
Then I adjusted the tabs on the side of the bulkhead to ensure they fit properly into the new slots I made on the sides of the fuselage.
Edit 06 Nov 2014 - nose tip mod
I forgot to mention this when I wrote the original post and it is completely optional since I did it more for aesthetic reasons to make the canopy appear a bit more further forward and the front nose section a little shorter. I actually made a mark 1/4" from the end of each "finger" on the nose and then as I cut it out I carefully cut in to that mark to make the nose section about 1/4" shorter once it was all glued together. Again, purely aesthetic, not necessary unless you want that look as well.
So hopefully this has been somewhat useful to you, some of what I did may also be explained in the walk around part I did in this video.
If I have confused you or you have further questions, please post them below or if you don't have a Google account, please e-mail me at migsrus@outlook.com and I will do whatever I can to help you out. As I mentioned earlier, it is an ambitious set of modifications, so I would suggest taking your time, measure carefully and don't hesitate to ask questions... :)
Cheers,
Scott
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