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Dec 01, 2020, 07:52 PM
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Mark:

Gliderguide got it exactly right. Using a covering iron is a great way to cheat, gluing down sheets of thin wood.

My own iron is a TopFlite iron for monocote, which I believe is actually forty years old by now. I have no idea what temperature it heats to. There is no on/off switch, just a reostat that rotates from "warm" to "hot". In my case, hot is VERY HOT, and warm is pretty much off. The dial is marked 1-2-3, and I use 2 as a good place for Ultracote. For heating glue, like I did today, I use 3. 3 is plenty hot, and I can use it to glue down thin plywood (up to 1/32" thick, if I am patient) or balsa sheet up to 1/8" thick.

Apply the glue (Titebond or Elmer's works fine). Let it set or not - your option. Place the wood where you want it, and apply the iron with some pressure. I try to nail down an edge, then work toward the free side.

Good luck!

Greg

Yours, Greg
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Dec 01, 2020, 07:56 PM
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Wing Construction - SHeeting


No pictures today. Too boring!

I completed all the rib caps, then finish sanded the left wing panel. It has a nice, airfoil shape. As I expected, the price of joining then sanding means that there is difficulty at the joint getting a good shape. Busywork, that is all.

What remains are the tip and the root rib. I will install the spoiler servo as part of covering.

Tomorrow, I may be able to complete the right wing, then add both tips.
Dec 02, 2020, 02:39 PM
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Gliderguide and Glidermang,
Thank you for the answers to my question. Much appreciated!
Dec 02, 2020, 05:37 PM
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Finishing the Wing Structure


Had a nice today: fog and snow, so, no excuse to stay away from the building table.

I completed sheeting the right wing. Just fiddle work, really. Then I took it out to my sanding table (the sky had cleared. It was cold, but not breezy). It was easy to shape, having practiced on the other wing.

Inside once more, I added the ply root ribs and balsa tip blocks. I taped the root ribs in place, even used 15-minute epoxy (well, why not? I won't use that for anything else). Tomorrow, I can cut down and shape the tips. For now, everything is either taped or clamped, waiting for sticky stuff to set.
Dec 03, 2020, 05:12 PM
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Completing the Wing - well, pretty near.


It is sunny today, so it was possible to work outside, as long as the shadow didn't creep over the work bench.

I left the wings with the root rib epoxied on, and the wing tip blocks glued in place. Today, we make the wing look "real".

The root ribs were easy to sand, to conform to the wing outline.

The tip blocks, though, have a whole lot of wood that must be removed. Also, I got caught up in wondering just how I should shape them. My natural inclination (conform to the airfoil on top, taper from the bottom) didn't make sense, since the tips are not aligned with the airflow. So, I marked a line that extended the leading edge of the wing, then came around to the top of the trailing edge. I determined to taper both top and bottom to within 1/8" of that line, then round off.

Said, then done. The pictures show the sequence, and I like the outcome.

Of course, I had some good tools at hand. My Permagrit block finally got the rough side used for initial wood removal. I refreshed the sandpaper on my 80 grit block, and that finished shaping. A piece of 220 grit polished out all the scratches.

Next time: shape the fuselage.
Dec 03, 2020, 08:49 PM
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That bench gets a good work out from all those gliders you build glidermang ......
Can't wait for the maiden....
Dec 04, 2020, 09:01 PM
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Fuselage - Sanding and Canopy


I got to work on the fuselage today. I have been nervous, because the need to shape some curves for good aerodynamics has never been my strong point.

Came out pretty good, though.

I set up in the sun, and went to work on the fin, first. I tried to sand it until all the steps between sheets of different thickness were gone. I found that a block, wielded gently, actually worked well at blending surfaces. I saved a piece of gently folded sandpaper for finishing.

For the fuselage corners, I first removed all the surplus around the nose, then went to work on the corners. My aim was to transition the rectangular fuselage to octagonal. It is easy this way to make sure the same amount of material is removed: just check the size of the new flats. Once I had removed wood to the point where longerons were almost exposed, I began the rounding process. Finally, I finished overall with a block of fine sandpaper, then went after the the rounded corners with a piece of sheet sandpaper. Just sort of polished out scratches.

For the canopy, I worked from the aft end forward.

The aft canopy started as two pieces of 1/4"X1/8" spruce pieces, sanded to match the curve of the top of the fuselage. Three cross pieces made a little frame, covered with the kit-supplied 1/16" plywood. Some additional sanding brought it rest on the brass tube through fuselage, and conform to the fuselage shape.

The semi-former F4A went on next, and the hatch now rests on Former F4, with the ply piece hooked over it. I marked a hole in the F4 bulkhead and drilled that for the wood dowel that locks the canopy down.

Now comes the aft block of the massive nose canopy. I had to trim 1/16" off the aft end, and with the seconf F4A attached, it fit perfectly. Drill that block, and insert the 1/8" dowel. It all fits, now.

Finally will come the forward block (tomorrow) and final sanding.
Dec 04, 2020, 11:40 PM
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gliderguide's Avatar
Nice work and a great build thread as always Greg. You will enjoy the flying too. A little different to your recent 2m RES bird’s I suspect....
Dec 05, 2020, 02:35 PM
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Such a great looking plane. Mine came out heavy as lead (I was like 17 at the time) but I did put a cool color scheme on it...all black except for red, orange, and yellow wedge stripes on the tips of all the flying surfaces. Wish I had a photo!

Really have enjoyed your build thread.
Dec 07, 2020, 07:44 PM
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More Fuselage Work


I had to take a day off, just for the rest. Also, to help get the house ready for Christmas! We got a tree yesterday, and everything.

Anyway, this kit continues to amaze and delight me. The designers solve so many problems in ways that I would never have thought of. Sort of explains why I am not a designer, of course.

I did a lot of sanding on the fuselage today, then finished the "hatch". It came out mush nicer than I anticipated. In fact, about 15 minutes into the shaping of the hatch, I was pretty sure it was not going to work at all. But, it came out fine. The hold-down plate was easy to fabricate, and even was useful before gluing as a way to determine whether the block was properly mounted. Once in place, I went to work on the hatch itself, smoothly blending it into the fuselage.

One extra thing I did: there was a slight gap between the hatch and the fuselage sides. I cut strips of wood from 1/32" sheet, and glued these to the edges of the plywood fuselage. Sanding them smooth was easy. No more gap, either.

At the same time, it was easy to finish smoothing off the brass joiner tubes, where they slightly protruded from the fuselage. They protrude no more.

It is time to choose: prepare the wing for covering (by installing the spoiler servos), or cover the fuselage. I think: prepare the wing!

It turns out that I had settled on opaque whit and transparent blue for this airplane. However, a guy in another forum is building a Sagitta 900 with the same color choices. He beat me to it, no doubt of that. I hope he doesn't mind me using the same colors.
Last edited by glidermang; Dec 08, 2020 at 06:09 PM.
Dec 07, 2020, 07:59 PM
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Glidermang, I have been quietly watching your build and am enjoying it ! I really like that full flying stab, pretty cool ! The wing is really nice, as well ! Have fun, Mike
Dec 07, 2020, 08:00 PM
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Dec 08, 2020, 06:25 PM
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Spoilers


Boy, I sure wish this sailplane was still in production. It has turned out not at all like I feared it would. The designers sure solved all the construction questions in ways that were/are new to me, and I have enjoyed it no end!

Today, after the morning spent flying in cold but sunny weather, I prepared the wings for covering. That is, I figured out how to actuate the spoilers and got everything ready for spoiler installation. I ran out of daylight (necessary for my workroom), so tomorrow, I can just glue in the spoilers, attach lead extenders, and then... Then, what? Why clean up the workroom, of course, so I don't compromise the covering with dust and debris.

For the spoilers themselves, the instructions suggest using left-over trailing edge stock. I toyed with making some myself, but whoa! They've been right so far. So, trailing edge stock it is, cut to length. But because I made the openings a wee bit too large, I added 1/16X1/14" strip to the leading edge. Fit is now just right.

Instead of the cumbersome strings and internal servo, I'm using a pair of Futaba S3114s. Light, and they fit, and they have been great servos for me. Moving spoilers on a 2-meter looks to them like child's play. I still have to add servo extensions, which I intend to buy. Gotta keep Hobby Proz in business!

Tomorrow, covering begins with the spoilers, using covering material to hinge them in place. Then, simply glue the servos in place, and good to go.
Dec 08, 2020, 06:26 PM
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Check this out! We both started a Sagitta build at nearly the same time.

https://www.rcgroups.com/forums/show...-version/page8

Yours, Greg
Dec 09, 2020, 12:05 AM
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The fuselage looks so good I feel like building one for my mantel.


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