blabberon

How about this! Page three and we are finally underway!!

Sure enough Doc, the smell of laser cut wood wafted out of the box!

I started cutting loose the parts for step one. "Wing Construction, Assembling the Wing Cage".



After a "dry-fit" run through I glued the assembly together with wood glue and let it set for the night.



Next I cut loose the ribs and spars and started, "Constructing the Leading Edge Spar". In the photo below the right hand wing assembly is up-side-down.



Jumping way ahead of the game I also marked a trim line on the vacu-formed wing tips by using a red felt marker on its side and sliding it around the perimeter of the part. Then trimmed off the excess with scissors and epoxied in place the outer most wing rib.



All the laser cut parts have fit together snuggly without any additional sanding required. Nice!

theo63

very nice im gonna watch this one thru looks like a great kit and looking forward to seeing more,steve

Flying Foot Doc

My Feedback: (2)

Good move on the wing tips. One of the few places I think I am going to modify is to make light fiberglass repalcements for the plastic wing tips. I've had some frustrating times with plastic ones before. I figure (?) as long as I have the originals, I can use them as a mold and mke plugs to remake my own. we'll see.... Keep going with your great photos and descriptions. Doc

blabberon

That's a good idea Doc about the wing tips but I will give these a try and hopefully not damage them. They seem pretty solid with the rib epoxied in place. Sort of like an egg. Strong until I crush it!!



The above photo is a close up of how the Aileron Cable Anchors are located. The laser cut parts fit like a glove. I used wood glue after a trial fit. There are simular anchors for the Flap Cable.



Here is the left and right wing glued to the "Wing Cage" and the rear spar in place.



And here is a start on the ailerons themselves.

I am trying to not go too fast and do a lot of checking between the manual and the plans. I read over the plans in the morning before I go to work in my shop in the afternoon. Check, check and re-check. The plans are very specific about where to use CA Glue and where to use Wood Glue. Also, right is right and left is left!! Things like that I try to keep in mind!!

wascamp

My Feedback: (1)

Boy Ron, you must have a tail wind because you are making great time. I told you this bird would go together fast. How long do you think it took you to get this far on the wing. I know there is a lot more to do to finish it, but It does go fast , No?

blabberon

Hi Roger,

Welcome back!!

I just got the kit late Monday so the wing only has two afternoons invested into it so far. Everything laser cut fits like a dream. It is up to me to make sure I assemble it correctly!! I glued two Flap Cable Anchors on the wrong side of the rib this afternoon but caught my mistake before the glue set up!!

I need to stay focused while working and know when to quit for the day when I start making mistakes! We are entering the rainy season here in Californie so there really is no reason to rush!!

Have you dusted off your MosquitoBite Tri-Pacer yet?

wascamp

My Feedback: (1)

Ron,
I need to finish the paint and it has been too cold for dope. I will work on it this summer between cutting wood, installing new differentials on my 4X4, and restoring my MGB. Oh, I forgot. Mowing the yard (5 acres this year). Right now I have three planes on the board. I am finishing a P-47 for a fellow back east. It is at the glassing stage. I have an antique Pilot Fighter Forty in tbe bones, and I am scratch building a Cessna 310 B for twin electric power. Mama won't let me dope in the house so that will have to wait untill it warms up. Epoxy is OK so that is what I'm doing now.

blabberon

Here are the finished ailerons. It may not look like it but they ARE right side up!! Interesting!


Then I installed the Flap Support Arms using a .094 rod to align the pivot points.


Flipping the wing over I assembled the Flap Ribs, Flap Horn, Flap Horn supports and Flap Pivot Ribs on the Flap Base and temporarly installed it on the Flap Support Arms to make sure everything lined up before committing to glue.



I did both flaps and they pivot nicely through 40 degrees! Oh Boy!


Here is the overall view. I'm stoked!!.

I did discover I installed one set of Aileron Cable Supports on the wrong side of the rib after all!!
Fixing that will be my starting point tomorrow!

wascamp

My Feedback: (1)

Ron,
Do the flaps get sheeting or are they just covered?

blabberon

Roger,

The flaps get sheeted with 1/16th balsa. Ken at MosquitoBite did a nice job of selecting the balsa for this kit. Light weight but straight grained.

The next procedure, according to the manual is to cover the ailerons and flaps with Ultrakote.

That brings me to the question I have had in the back of my mind for several months. Let me pose it to this forum.

What are the most visible colors for a RC model this size? (72 inch wing)

I do not see as good as I used to. I scare myself sometimes with my UltraStick 40 when I make a turn on final because it will disappear on me for a heart beat or two during the turn. (We have to make our turn and decent with a hill of Redwood trees in the background. The small profile of the Stick doesn't help.

I have heard Red and White are the best all around colors for visibility but I'm wondering if maybe stepping up to some DayGlow, "Coast Guard Orange" color accent on white might help.

I know the Robin is a S.T.O.L. plane and should be a great, close in, slow flier but I will probably also want to see if the 80 mph claim by Andy Lennon will make it possible to keep up with the "Go fast. Turn left" guys in our club!! Just as an experiment, you understand!

wascamp

My Feedback: (1)

Actually it's called International Orange. Coast Guard orange is actually called Coast Guard Red. go figure! White is the color with the best all around visibility. I did a Sig Kadet in all white with orange on the wings from the tip in about 6 inches. I put the orange on the upper surface only so I could tell if the plane was turning toward me or away. I too have problems with orientation and that seemed to work for me.
Bright orange works just fine. Day glo fades for some reason. In a season or two it will look like hell.

Flying Foot Doc

My Feedback: (2)

Since you asked about colors. For my purposes, I find very contrasting colors the best. I like a solid top color wing like Red with big 6+" or more white wing tips. For the bottom of my Robin I'm strongly leaning to a checkerboard pattern. I've had translucent...couldn't tell which side I was looking thru. I had one with one big color change stripe on top & 2 big color stripes on the bottom. I got it into a spin & I thought it looked like it was getting mixed in a blender. Came away for the rapid decelartion event with the ground just like all those little pieces had been in a blender. One guy in our club puts a thin reflective stripe along the leading edge to help orient the oncoming wing. Keep up the good work, Doc

Cdallas2

It's not so much the colours as it is the shape. I have a great link for a website directly related to this:

http://www.ultimatecharger.com/color.html

Check out the Pattern guys airplanes as well. They are meant to be seen in the air - not pleasing to the eye on the ground

Flying Foot Doc

My Feedback: (2)

Very well done paper, with very good logic and science. I think I can recall almost all of teh color mistakes you mentioned. Doc

blabberon

Thanks guys for the color and pattern ideas. Speaking of contrasting colors, my father used to have a black and white 1955 Packard Clipper. No trouble with orientation but I remember half of it was always dirty!!

I covered my Pete n Poke in Black and White but I did the fuselage the other way round; black on top and white on the bottom contrary to Doc (2)'s suggestion. I'll have to give it some thought. Thanks!

While I think about color and pattern let me confess something.

Truth be told. I am an idiot! I discovered I didn’t glue the Flap Cable Anchor on the wrong side of the rib. It IS correct. The problem is I built two right hand flaps!! (Pay attention Doc!!)

Yes, there is a wee difference between the right flap and the left flap! The actuator arms are located about a quarter of an inch off the center of each flap!! If it wasn’t for that wee offset the flaps would be almost identical!! Fortunately I had not glued on the 1/16th thick, balsa sheet, top half of the flaps so I was able to remove the flap ribs, flap arms and the actuator piece, flip the Flap Base over and glue these parts on to the “correct side”.

Now both flap actuator arms line up with the flap cable anchors!

I then installed the top sheeting on both flaps. This is a bit tricky and I highly recommend sorting through the 1/16th sheets of balsa and picking two sheets that will wrap around the flap curve somewhat easily.

Next I put them temporarily on the wing. I sanded out a bit of flap gap interference by sliding some sandpaper between the flap and the wing trailing edge (grit towards the T.E.) to get the flaps to close to 0°. It didn't take much and now they are perfect. No gap when closed and a nice even slot when opened.

I like it but it took all Friday afternoon!

On Saturday and Sunday we fly, weather permitting and the weather permitted!! Our flying field is only accessible on weekends because it is on logging property. Monday I have to make a run to San Francisco. Tuesday I will resume the Robin Build.

Onward!

blabberon

Okay, where were we?

Typing is sort of weird with CA on my fingers!!

I was to the point of putting on the leading and trailing edge "skins", D-tube style, when I noticed things were not straight. There was a bit of a "S" shape when sighting along the main wing spar from one end to the other! Not a lot but more than I wanted to "lock in".

I called my flying friend and asked if I could use his big flat table and could he maybe help me get this wing jigged into straight and true.



So, today that is what we did. Screwed some 90 degree angles to his building board and then measured and shimmed and clamped where necessary to get the wing straightened out.



Then I glued on the 1/16th sheeting from the rear spar to the trailing edge, from the main spar forward and down to the leading edge and then added the rib cap strips.

Tomorrow I will lift it out of the jig and flip it over for the bottom sheeting.

I'm glad I went to the trouble to take the 1/8th inch wow out and make sure the dihedral and incidence were the same, end to end.

I had heard the MosquitoBite Tri-Pacer wing could be built in a bench vice but that's not a good idea for the Robin wing.

By the way, I bought a DX-7 radio today for the Robin because that transmitter has a three position flap switch on the left hand side!!

Flying Foot Doc

My Feedback: (2)

Nice job and good info on the wing alignment. I have to figure where I'm going to have to do the wing alignment in my shop/garage. Are all those clothes pins clamping the sheeting or just acting as weights to hold the leading edge down? You are really motoring on this build. Doc

blabberon

Morning Doc,

I used wood glue on the ribs and 1/4" leading edge piece. Then CA-ed the sheeting to the balsa spar to hold it in place, then wrapped the sheeting down to the leading edge and clamped it with clothes pins.

Today I will use wood glue to attach the bottom sheeting to the leading edge. That way the leading edge should be easier to sand to its final shape.

Anyway, that's my plan and I'm sticking to it!!

fordboy76

I really like this plane and am excited to see someone building one. I have yet to build a kit and was wondering if this would be a reasonable kit to start off with.
Sadly, I am finishing my basement and cannot build just yet, but I have designed a sweet hobby room/office that I plan to have comepleted in may. After that, I will fly the guts out of the planes I have and start with a kit. I have toyed with the idea of a red star yak, skyshark dauntless or stuka, or the robin. I am leaning toward the robin as it sounds like it flies just the way I want. A nice sunday flier that has a good dollup of spirit. The fact that it will be unique from the normal crowd of ARFs is definately a plus. Seems the only guys with the unique stuff come on weekday mornings.

Keep up the great work.. I am relying on you to keep me from catastrophic mistakes

blabberon

I don't think this would be a good "first kit". I'm sure there are folks on this kit building forum that could recommend a good "first kit". I have built several kits, my last one a Great Planes Pete n Poke, which I love but this Robin kit is quite a hand full. Just the wing is keeping me on my toes!! But maybe it's just me. I'm getting older!!

Today I installed the lower forward sheeting. Once again I held the wing straight and true with jigs before adding the outboard sheeting for the the NASA Droop and then the regular inboard wing sheeting.



The NASA Droop has under-camber so I used a combination of CA here and wood glue there to get the sheet to hold in place while the wood glue set up. I used wood glue on the leading edge so it will be easer to contour when the time comes. I had to use pins this time as clothes pins would no longer work.



Inboard looking out.

Here is what the designer, Andy Lennon, had to say about the NASA Droops.

"Ahead of the ailerons, the E197 airfoil is modified to NASA development leading edge extensions and droop that do three things; the stall is delayed a further 9 degrees, aileron control at high angles of attack is effective and there is no tip-stalling, important for STOL landings."

Tomorrow I have a bunch of filler pieces to install to enclose the space in the wing just ahead of the flaps and the area just ahead of the ailerons. Then the lower rear skin and the lower cap strips can be installed.

Thanks to my friend Dick for helping me get this wing straightened out. "Next time" I would build it over the plans even though it would have to be up-side-down because, right-side-up the NASA Droop and the Flap brackets are in the way.

Tricky business!! [>:]

blabberon

I moved the Robin wing back to my shop.



Using some tracing paper I traced the outline of the leading edge of the NASA droop and the inboard leading edge from "Sheet Two" of the plans, then contacted cemented the tracings onto some thin plywood stock. I band sawed them out and hand finished to shape. Using these templates I contoured the inboard and outboard leading edges.



Next, I started cutting and fitting 1/16th balsa sheeting between the trailing edge ribs to close off the space ahead of the flaps. They will also support the lower trailing edge. Six pieces per wing.



And here the trailing edge piece is cut to size and fitted.

Lots of fiddly work and it sure ate the afternoon! []

Flying Foot Doc

My Feedback: (2)

Great idea on the templates. Your work is definitely taking shape. Keep up the good work, Doc

blabberon

Thanks Doc,

This wing is taking a lot longer than I thought it would. Getting it straight to begin with would have saved a couple of days! Now that it is straight I find there is a lot of piece work involved with the trailing edge area, sanding the trailing edges to fair and getting the gap correct on the flaps. I am learning the straighter I build parts to start with, the easier additional pieces will fit. Let me say it again... the flaps are tricky.



I gave the wing tip a trial fit. It looks like it will fit just fine. (The trailing edge is not sanded to length, yet.)



I also delved into installing the Golden Rods for the Aileron and Flap cables. I soldered on the Sullivan Link to the cable that actuates the flap. The wing is upside down in this photo and I have the flap and wing spaced apart to illustrate how it is set up. A "push/pull" action deploys and retracts the flaps. It works because the flap pivot points are located about an inch below the wing. (The Golden Rod, cable and Sullivan links came with the kit)



This is the routing of the aileron and flap cables out from the central servo tray. Laser cut holes were already in the ribs to locate the Golden Rod. Sweet!

Flying Foot Doc

My Feedback: (2)

Blabberon, is there an access hatch to the clevis goldenrod area after the whole assembly is together? Good looking construct so far. Doc

blabberon

Doc,

The clevis attachment points on the flaps and ailerons are accessible but hopefully not needed once assembled. As for the attachments of the flap and aileron cables to the servos, yes, they will be fully accessible.

Now then……

Since I seem to be the one breaking ground on this build let me confess my mistakes so others can avoid them. Note: I am what I would call, an average builder (maybe I’m optimistic), smarter guys and gals will have enough foresight and wisdom to avoid these mistakes!

On page seven of the manual the instructions say “…after assembly of the aileron, cover the aileron with Ultracoat”.

Well, hey! I had not decided on what color Ultracoat to use so, I skipped that part.

Yesterday that decision came back to bite me because yesterday I temporarily taped the Ailerons in place, retracted the Flaps to 0 degrees, made a template of the chord length of the wing from the plans and set about trimming the wing to length. Simple. Constant chord. Nice and straight. Perfect!

I then removed the Ailerons and looked into covering them with Ultracoat (which I now have). In the process I discovered I had about an eighth of an inch “overhang” where the aileron hinges to the wing!! If I had finished and covered the Aileron when the manual recommended I would have noticed this and trimmed off the overhang before I “finished” the wing to length!

Now, with the ailerons trimmed to length, they are shorter than the flaps by an eighth of an inch! Now, I have to re-cut the flaps to the new shorter length or add to the ailerons trailing edge. Either way it isn’t much but…. Dang!

It has also become apparent it would be best to finish and Ultracoat the Flaps when they are assembled back there on Page 5!

My other mistake… I cut one flap actuator cable too short by an inch and a half! I had “assumed” (there’s that word again) both right and left flap cables would be the same length. Wrong! The flap and aileron servos are side by side, either side of the centerline and so one flap cable needs to be about an inch longer than the other.

I fixed my mistake by adding cable by using a brass sleeve and solder. That brass sleeve, now visible in the servo tray area, will serve as a permanent reminder to, “check, check and double check”!

Another interesting feature, which is not mentioned in the manual but noticeable on the plans, is the way the aileron cables attached to the aileron servo arms. I will have photos soon but be aware that there are (two) holes laser cut in Rib A and Rib B for the ailerons and (two) for the Flaps. They are labeled A 1 and A 2, F 1 and F 2. The Left Wing is 1. Right wing is 2. All this because the cables come into the servo tray “over and under” for the Ailerons and “forward and back” for the Flaps. The aileron servo uses two arms of a Dubro four arm servo arm. They are 90 degrees to each other facing forward; like a V. The left aileron attaches to the right arm. The right aileron attaches to the left arm! One to the topside of the servo arm and the other to the bottom side of the other servo arm. This way they won’t interfere with each other where they cross.

The end result is proportional ailerons! Cool!