RC Powers T-50 V5 build log - Part 6...finally finished :)

Hi Everyone -

One modified RC Powers T-50 V5 ready to "slip the surly bonds of earth"😊

I may have mentioned in a previous post that I was thinking of doing the black, white and grey Arctic camo scheme like I have on my test bed Mig-35B, but I decided to go with a "blue" theme this time for something different.  I think it turned out OK, either I thinned the paint too much or the Minwax treatment on the DTF where the paper is didn't allow for terribly good paint coverage.  No matter, I could put another coat of paint on, but that would add weight.  I'm more worried about how it looks at 200 ft away (to help my poor old 56 yr old eyeglass assisted MK 1 eyeballs keep track of it😒) than how it looks at 2 ft away😉

My AUW with 2200 3S battery is pretty good, 552 gr/19.5 oz, so I think it should be pretty light and quick.  I decided to put the EMAX RS2306 2750 Kv motor in this plane as it is billed as being pretty fast according to RC Powers, so I might as well give it the motor it deserves😉.  I will run a 6x4 APC prop and 40A ESC.

I mounted my rudder servos in the back first so that I could then run the rudder servo wire outside the prop slot and then back in through the hole where the elevon servo is mounted.  This will ensure no possible interference with the prop by the rudder servo wires.

As I discussed in my servo video, the wires on the 5 gr servos aren't very long, so since I use a "Y" harness to connect my servos to the receiver, I ran the two Y leads out from the electronics bay so that I could connect the rudder servos, then tacked everything down with a bit of hot glue, including making sure the rudder servo leads were secure in the Y harness plugs.

I decided to trim a bit off the rudders themselves as when it was sitting on the table, these were completely flat on the surface, so by putting a slight angle on them, hopefully this won't cause such an abrupt landing as I flare it in.  I probably trimmed about 1/4" off the back and then angled it down to the rudder hinge line.

For durability, I always spread a very thin layer of glue (this glue which is identical to BSI Foam Cure) on the nacelles and along the bottom of the nose.  It dries light, clear and hard like epoxy, but doesn't turn yellow over time like epoxy does.  Fortunately, I can get this at a local dollar store and it is much cheaper than Foam Cure.

A bit hard to see the glue in this picture, but where it is shiny shows the glue.  I darkened this with black magic marker first to help with orientation.

I put a thin layer on the bottom of the nose forward of the small air vent.  Since the T-50 doesn't have a lot of nose clearance off the ground (especially since I lowered the nacelles by 7 mm), I suspect occassionally on landing it may tilt forward as it comes to a stop.  This glue will help the foam from getting gouged and torn.

Although I won't know how the build and my modifications turned out until I get a chance to fly it, I'm quite pleased with how it looks and with my final flying weight, I think with the fairly low profile it will be a pretty speedy little beast.  More to come as I get it in the air and start putting it through it's paces.😊

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

RC Powers T-50 V5 build log - Part 5

Hi Everyone -

My build is starting to look much more "T-50ish" now😊  The vertical stabilizers are dry fit for now and won't be glued on til later on in the build to make installing servos on the bottom easier.  In this current state with no gear, sanded, it weighs 177 gr/6.2 gr which is about what most of my planes weigh at this point.

 I'm very happy with how the vertical stabs turned out, still a bit bigger than scale but I think much closer to the right shape than the stock vertical stabs.

I decided to make the nacelles a bit more scale and lowered them somewhat.  I measured what they would be on the T-50 V1 (which has a 24" wingspan), then converted that number to what it would be on a plane with a 27" wingspan and ended up trimming 7 mm off where it meets the wing plate and also made the rudder less wide as well.  I know you wouldn't know the difference in this picture, but it does lower the profile of the plane considerably.

I remember when we were testing the NAMC Mig-FA which is a concept design my former NAMC partner Stephan designed, the nacelles were similar in depth to what was on the Mig-35, our first plane.  As we dialed down on more "scalish" looks since it was loosely based on the T-50, when we lowered the nacelles, the plane was faster, more efficient and much quicker in the pitch and roll as the vertical profile had been reduced considerably.

Perhaps because I lowered the nacelles down, when I dry fit the motor with prop attached, it was hitting the bottom of the nacelle.  I had to trim quite a bit off to give the prop clearance.  Starting where the pen is pointing in this picture, I trimmed forward about 1 and 1/4" along the outside, just angling in towards the inner part at an angle so as not reduce any strength and structure around the motor mount area.

To taper the leading edge of my wing and LERX, I draw a line about 3/8" back from the squared leading edge and then use this as a guide to trim the foam off before sanding.  Bottom.

Top

 

I have always done a bit of a "sharp edge" on the leading edge of the wing with the KFs.  I have read and heard arguments that this leading edge should be rounded, and maybe I'll try that sometime and see if it makes a difference, but I have done it this way with dozens of plans, so perhaps a case of stubbornness on my part or "if it ain't broke, don't fix it"😏

Finished product, I know it is hard to see with everything being white, but it is smooth and sleek now😉

Holes are cut out for the servos and I have also cut a relief out of the bottom KF so that the elevon and aileron servos can be installed easily.  In the first picture, from left to right will be the aileron, elevon and rudder servos (same on the other side of the plane)

This relief is cut about 3/4" inch away from the nacelle to allow the servos to be installed easily and also allows for the "flanges" on the aileron servo in the front.

Still a bit more fussy work to do, I will apply the oil-based Minwax to the paper on the bottom of the plane and let it dry overnight, then paint the sides of the nacelles, install all the servos and pushrods so that all the work on the bottom of the plane will be done.  Once that is done, flip it over, glue on the vertical stabilizers and then treat the paper on the top of the plane and ensure that is completely dry before painting the rest of the plane, installing the motor and it should be ready to "slip the surly bonds of earth"😀

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

RC Powers T-50 V5 Build log - part 4

Hi Everyone -

In among all the holiday cheer, I managed to putter away a bit on my T-50 V5, mostly getting things ready before mating the fuselage to the wing plate.  One thing I like to do is mark where my elevon control horns will go.  Knowing that where I will be connecting the pushrod to the servo is approx 3/4" out from where the servo will be mounted in the side of the "nacelles", I use the slot that marks where the nacelle will fit into the wing plate as shown in the second picture.

Then using one straight edge as guide, I make a mark on the elevon on both sides so that I remember where the control horn will be mounted.  I rarely use the control horn marks that are indicated on the plans as they rarely line up with where I want to put my control horns.

I used 150 grit sandpaper to taper the trailing edge of the wing, the leading and trailing edge of the prop slot, the leading edge of the horizontal stabilizer and all around the outside edge of the elevons to help keep things sleek.  I like to do all this sanding before mounting the control horns, but I forgot to take a picture of that😏  While I can lay the wing plate flat is also when I sand the hinge tape on the ailerons and elevons so that it is no longer shiny and paint will adhere to it much more easily.

I also tapered the outside edge of the vertical stabilizers and added some bamboo skewers for extra reinforcement.

Before being able to join the fuselage to the wing plate, I needed to glue the front part of the wing plate on.  You may remember that this part was cut out separately so that I could get the wing on a 20x30" sheet of Dollar Tree foam (DTF).

I start by taping the two pieces together as shown below.

I then hinge these two pieces open, exposing the edges of the foam as shown in this picture.

Then using 5 minute epoxy, I spread a fine layer on each side of the foam, then lay it flat with the tape down (I always put wax paper under it so that I don't have any ooze out and glue my wing plate to my work table).  If any excess epoxy oozes out on the top as shown here, I take some scrap foam and spread it smooth ensuring any gaps between the two pieces of foam are filled.

Then another piece of wax paper goes on top of that seam and I weight it down with something so that the joint dries nice and flat.

In the next picture below the video, you can see that I have put the "insurance" tape on the bottom of the elevon hinge as I describe in this video at about the 7:50 mark.

Control horns mounted using epoxy.  

So lots of "fussy" work done now, it is just a matter of mating the larger parts of the plane together, finish constructing the fuselage, attach the "nacelles" and "under rudders".  

Still coming together, slow but sure😊

Happy New year for 2018 everyone🎉🎆

Park Jet noise...the "other" sound of freedom😎

Cheers,

Scott

RC Powers T-50 V5 build log - Part 1

Hi everyone -

As I wait patiently for all the quad motors I have ordered to show up, I decided I might as well pass some time when the weather isn't conducive to flying building a new plane, at least one that is new to me😊  So I decided on the RC Powers T-50 V5.

On their website, RC Powers claims "this one is even faster" so I assume they are comparing it to the F-22 V5, my favorite of all the V5 series thus far.  So I'm game for the challenge, plans are printed off already to build it at 95% just like I did with the F-22 so hopefully once everything is taped together my wingspan should be about 27".

I plan on building with a combination of Dollar Tree foam (DTF) and Depron to minimize weight and drag while maximizing strength.  Like most of the V5s, once I have everything cut out the build should not take too long as they have a fairly low parts count.

Like I did with the F-22, I will move the motor forward at least 1" if I can to help compensate for the weight in the back end of the paper left on the DTF.  I will probably make the vertical stabs out of DTF to keep those thin and make the elevons from Depron to reduce build hassle and the amount of reinforcement needed to keep those strong.

I will know better what other mods I want to make once I get the plans taped together and get an idea of proportions of everything.  I suspect I might be reducing the vertical stabs a bit to help the scale look and to reduce some drag.  Ailerons will be increased in size to be similar to those on the F-22 and I may fashion the "boom" between the ailerons like on the real T-50, now being referred to by Wiki and most of the rest of the world as the Sukhoi Su-57  However, I will continue to refer to it as the T-50 to prevent confusion😉

I will also be modifying the prop slot and the nacelles so that I will be able to run a shorter quad motor in this plane like I have with my last few builds.  I will continue to update the blog as I make progress, hopefully passing along my thought process for why I am doing certain things the way I do and lessons learned as I go along😊

Should be fun!

Park Jet noise...the "other" sound of freedom!

Cheers,

Scott