Upscale Gyroc With A Twist

[Gary Byrum]

I guess it all depends on your mood but lately I have been up scaling some kit designs and this is another in that league. I have never built an Estes Gyroc before and I have some new angles I hadn't seen in other build threads. Maybe it will answer a few of the questions asked about them darn hinges! We'll get to that later.

First off, I am going with an airframe BT 55 and a 24mm rear ejection motor mount with it's own streamers. There's good reason for this too. Pictured below is the airframe, motor mount with 3 fiber centering rings, a 50/55 bulk CR (which is going to be the motor mount block) The block of balsa wood in the clamps will be the nose cone. I glue hard cardboard to both sides to secure the wood in the lathe so it doesn't chew up the wood. Just ignore that down scale Cricket/up scale Swift...take your pick. It's not important. That motor mount block was hollowed out a bit on the inside to allow the motor mount to pass through easily but block the MM from any forward access, Everything fits like a glove with a very small recess of the aft ring barely inside the airframe.

 

[Gary Byrum]

Next is the raw cut of the fins. Those got sanded to conform with each other. Later afterwards they got their share of sanding sealer on one side.

 

[Gary Byrum]

That block of balsa in the clamps? Looks like this now and is drying as we speak with sanding sealer. I call it a BNC 55B in honor of it's lil brother the BNC 20B.

 

[LW Bercini]

That block of balsa in the clamps? Looks like this now and is drying as we speak with sanding sealer. I call it a BNC 55B in honor of it's lil brother the BNC 20B.

Did you embed a dowel inside the nose tip like you said you would?

 

[fyrwrxz]

"GYROC with a Twist"-ya just gotta hand to this guy-luv it! LOL!

 

[Gary Byrum]

Did you embed a dowel inside the nose tip like you said you would?

That step takes place today. I guess I could have done that before I sealed it.

 

[Gary Byrum]

I drilled a 1" deep hole in top of the nose cone and secured a hard dowel which was later cut and shaped. This will be an advantage to the nose when it hits the surface. It got it's 1st coat of filler putty also. The fins and flaps got their 2nd coat of sealer yesterday and were sanded this afternoon. That little white card was a template for marking the rudder fins which was done also.

 

[Gary Byrum]

Now to eliminate any issues regarding the history of the hinges, I opted to go with some brass hinges. These were placed how you see them and traced. The back side of the fins and flaps are held together with some blue tape so they don't slip.

 

[Gary Byrum]

It was pretty easy to fold the flaps back and cut the inlay sections out with my preferred cutting device. Took a squared off sanding stick and cleaned up the edges and the surface of all inlay slots.

 

[Gary Byrum]

It was now time to mount the rudders. :eyepop: OMG! My mark is off by 1/4 inch! YIKES!. OK, go with line of sight and mount them where they are spose to be.

 

[Gary Byrum]

The rudders for the other side of the fins got mounted, the glassine on the airframe was removed where fins mount and got some pre-glue. The hinges got scuffed up on the side that mounts because I thought it might be wise when I epoxy them in the fins. And they might be hard to see but up front are 2 flap retainers. These are double sided and will mount on the motor mount. Since the MM is rear ejection and not secure, it could take a notion and turn. This is why I am not using the old single tab method. A brace on both sides just make sense to me. The nose cone got a second filler coat and was sanded also. It's finished.

 

[Gary Byrum]

"GYROC with a Twist"-ya just gotta hand to this guy-luv it! LOL!

Are you starting to see the twist?

 

[Eric1]

Gary, May I ask where you found the hinges? I've been wanting to upscale a Gyroc myself!

 

[Gary Byrum]

Got mine at Lowe's. Picked out the thinnest ones I could find. I won't be using the screws in this build though. You'll find them in the decorative hinges area along side of the regular hinges.

 

[Eric1]

Thank You Bro

 

[Gary Byrum]

Thank You Bro

Eric, Just 1 note about the hinges. I had one that was a little tight and the cuff around the pivot rod had to be manually tweaked. Those rudders are angled at 62* and it would be wise to have them all pivot freely at 90*. Just a heads up.

 

[Gary Byrum]

Today was a bit challenging. It was time for hinges to be installed and I needed to epoxy those. So I taped the flaps to the fins for alignment and applied the hinges. Thought it might be a good idea to prop the flaps slightly just in case some epoxy worked it's way between the fin & flap. Next I shaped the flap braces by sanding a curve into the root edge for a snug fit and all edges therein. OK, satisfied with that. That roll of orange caution ribbon will be the streamer material. With a 1/16" space to play with, I have room for a mile of this stuff. Those hinges, btw, are flush with the surface of the balsa.

 

[Gary Byrum]

I picked up the card stock I mixed the epoxy on to see how stiff it was because I wanted to remove the tape from the fins. It was drying well but still a bit malleable. Once I did that I tried to fold the flaps into position only to find THEY WERE NO LONGER ALIGNED WITH THE FINS! They were riding a little high and I almost panicked! So I went into gear and broke out the clamps and wide popsicle sticks.I clamped those buggers on both sides of the rudders to flatten everything like it was spose to be. GAWD! I hope by morning (or whenever I get my AIG) to go up there, that they survived the trauma. Keeping my fingers crossed. Would you look at my bench? What a nightmare!!!

 

[Scotty Dog]

I guess Ive been snoozing cuz I missed this thread.
Looking good Gary. Cool bird to upscale
I havent gotten glue on my fingers for awhile now.

 

[Gary Byrum]

I guess Ive been snoozing cuz I missed this thread.
Looking good Gary. Cool bird to upscale
I havent gotten glue on my fingers for awhile now.

I have spells also Scotty. Sometimes I go weeks without any inspiration. I suppose going to the last ROSCO launch in SC got me in gear again. All of a sudden I have a plethora of makes and mixes going on. Hope you get your groove on soon. Been a long time since I saw a new build outta you.

 

[Gary Byrum]

Fortunately my clamp job worked and yesterday I mounted the fins. That sat a few hours and I was able to get a putty filler coat on.

 

[Gary Byrum]

I would have sanded all this off for the 2nd coat but I didn't have time to do that. And for those curious eyes that see the upside down Lil Cricket in the background, it's only masked paint stripes drying. This Gyroc is starting to look like a Gyroc.

 

[Rocket86]

Would you look at my bench? What a nightmare!!!

The Gyroc is looking great. IMO your bench is far from a nightmare, as you can still see it.

 

[Gary Byrum]

The Gyroc is looking great. IMO your bench is far from a nightmare, as you can still see it.

I do a little maintenance before a photo shoot. Generally, it's a cluttered mess. I have 1 sq ft of space I work in on a bench that is aprox. 3.5 X 5'. It ain't much but I know if it were bigger, so the clutter would be.

 

[T-Rex]

I am a little curious about the hinges. What made you go with the brass instead of nylon from a hobby supplier?

Looks great. Been many many moons since my Gyroc ('74 or so....) Your ailerons look bigger, might actually rotate like it's intend

 

[Gary Byrum]

I am a little curious about the hinges. What made you go with the brass instead of nylon from a hobby supplier?

Looks great. Been many many moons since my Gyroc ('74 or so....) Your ailerons look bigger, might actually rotate like it's intend

Terry thank you. Everything was scaled up accordingly so there shouldn't be any variances. As far as hinges go, I opted to use what was more conveniently available. The brass hinges actually work very well and I have used the same kind in a Rotoroc spinoff I build several years ago with helicopter recovery and they are still working great. They are very light and I can get them at Lowe's. No need to order anything.

 

[Cookie the Dog's Owner]

I've been feeling a Gyroc coming on myself for a while now. I shall be very interested in how this one turns out.

 

[Gary Byrum]

I've been feeling a Gyroc coming on myself for a while now. I shall be very interested in how this one turns out.

Cookie, the last couple of days it's been fill & sand. I just filled fins again today and will sand tomorrow. I should have a pic or two to post sometime tomorrow. I didn't wanna bore anyone with a usual 'least favorite' part of the build. We all know EVERYBODY LOVES TO SAND! :eyeroll:

 

[Gary Byrum]

All of the putty filler sanding is done...YAY. It ain't easy to sand a Gyroc with hinges. I had to use 3-4 different sanding jigs to get the job done. And since I like to let the filler dry over night it took 2 days to get this done. OK....so everything is moving right along.

 

[Gary Byrum]

You notice there's a letter "A" on the engine mount next to the flap brace which, btw, both were installed today. That "A" will match up with another "A" drawn on the main body tube. The need for this was because my fins aren't exactly 180* from each other. One is slightly angled wrong so now the braces are designated. It's not enough to matter a whole lot in the big picture, but it does require the need to be installed accordingly. After I glue the nose cone it'll be about time to prime it.