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Old Dec 25, 2006, 09:40 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
The Shape of Things to Come

Sorry this picture isn't very good, but this is the approxomate side view of the fuselage...
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Old Dec 25, 2006, 09:57 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
Center Section

Here's the center section of the wing with the extra D-Tube reinforcement. It's ready for that 3/32" upper sheeting that helps stiffen the section, torsionally. You'll probably notice that the ends are still roughed out and the last ribs are not in place. I will sheet this and then remove the excess sheet from the leading edge. I'll then run it through my table saw... ... set at 4 degrees for the dihedral. I use a carbide, 60-tooth blade, and they come out just about perfect every time. I sand them very gently and finish them out. Then I'll join the wing sections. I cut and bent my joiners today. Remember that the spar slants back as well as up in this polyhedral joint. The joiner will glue permanently into the outboard portion of the wing, and the tube will be in the inboard. If you're an experienced builder, you may of course deviate from any of this to suit your particular style of building... but be careful to use tried and true methods. Also... please don't interrupt the spar / D-tube system in any way.

A word of caution about cutting this. It contains carbon fiber. I do this and the sanding outside, wearng a mask. I hope you will protect your health in the same way... and don't forget those safety glasses...
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Old Dec 25, 2006, 10:09 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
Outboards

Just a glimpse of my outboard panels. They're ready for joining. The joiners and plywood ribs are not permanent, yet. One tip's carved and sanded, the other isn't. I always get a lot of comments about my tips so I thought it might be nice to show just how easy they really are to do. Even though they're mirror images of each other, you really can make them darn near identical... more tomorrow. Gotta go out and check the Gorilla Snot on the main panel. It's pretty cold, but I have the heater running... My electric bill is going to be bigger than my material bill for this build...
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Old Dec 26, 2006, 11:11 AM
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Broomfield, CO
Joined Nov 2004
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Jack Ill be looking forward to your fuselage design progress. I am a fan of of the "straight top" fuse profile myself and im working on a 2meter design utilizing that myself. Im working through some of the building steps before moving ahead on mine. Harley Michalis (sp) used a similar "line" on some of his models including the Jester I believe.

Greg
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Old Dec 26, 2006, 12:01 PM
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Schrederman,
Great job on the thread AND the model so far. As I follow along, I'm either learning something new or validating techniques I've used in the past or considering using in the future. Keep up the good work!!
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Old Dec 27, 2006, 02:59 PM
Silent Wings
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United States, TX, Amarillo
Joined Aug 2005
670 Posts

I just have to throw my 3 cents in here, Jack......however, I think it has been stated before....."DON'T YOU EVER BUILD ANY UGLY PLANES?"
Great build article, and it assists me in my Big Bird build.
Thanks,
Gerald
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Old Dec 28, 2006, 09:48 AM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
Joining Panels

Well, as I said, this portion of the design has changed significantly. I originally wanted to use straight, short joiners. That didn't work out too well because what was used didn't fit with close enough tolerance. That allowed the outer portion of wing to move about some and at speed, that spells flutter. Consequently, I ended up bending 3/8" aluminum rod to 8 degrees. We will then use 13/32 brass tubes for receivers in the main panels. To start, there's a hole in the plywood panel-end ribs that mates up to the spoiler tube holes in the balsa ribs. I used that to index and glue on the center section plywood rib. This starts you on the road to a near perfect joint. I then used some 3/16" long pieces of yellow nyrod inner to index the plywood ribs together. These will later be replaced with some pieces of 1/8 cf rod that will firmly index the panels. I then made everyting fit that scenario, with the joiner epoxied in place. Be sparing with the epoxy, as this is just to get things firmly in place. We'll fill the voids when everything fits and we're happy. Use the same epoxy you're going to fill the void with... no 5-minute stuff... please... Here's what I came out with...
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Old Dec 28, 2006, 09:58 AM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Table Saw Accuracy

The first time I decided to use a power saw to do something like this, I questioned my own sanity... However, if you are blessed enough to have such an animal... you can save a lot of sanding and cussing... ... theh joints seen here were not sanded at all...

Here's an example of just how accurate you can be. Remember, I use a 60-tooth, thin-kerf, carbide-tipped blade. I've seen 80-tooth blades, and will buy one some day...
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Old Dec 28, 2006, 12:55 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
Tips on Tips

I really love the aesthetic beauty of a sailplane. The lines are often like some nice sculpture, or more often, mimmic the lines found in nature. I have seen wing tips go from pretty boring back in the '70s to really nice stuff like we see on the full scale stuff today... and on the moldies and other ARFs available in the hobby market.

Consequently, I've been carving my balsa tips to imitate these for the last several years. Just thought I'd share my methods, here, to maybe help beautify the fleet...

First, is to cut the tips from whatever thickness balsa you want to use. I like to cut them at the same time, slightly oversize, and sand them, again at the same time, to ensure the same shape from a top view. I then drag out the old, broken and glued French curve... no telling how many pieces of sheet balsa and Monokote have been cut around this thing... I place it on the trailing edge of the tip block, and move it until I have the curve I want. Then I mark the Fench curve with a couple of tics from a permanent marker so I can flip it and get the exact curve segment for the other side. Using a black, ballpoint, I mark the curve on the trailing edge.

Here's what we have so far...
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Old Dec 29, 2006, 02:14 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Bottom First

I always do one to near finished, and then mirror it with the other. There's no substitute for going slowly and checking often. You can make it smaller... but the only way to make it bigger is to start over... which you may have to do on the first couple that you try. I recommend that the bottom be rough shaped first. You'll probably notice that on mine, the actual tip is about 3/16 behind the straight trailing edge of the wing... it's just a little sexier that way... don't you think?
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Old Dec 29, 2006, 02:23 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Tools of the Trade

I like to use a sharp, 1/2" wide chisel, and a piece of 60 grit paper either on a block, or something round, as is necessary. Again, I stress using very sharp tools, and be safe here... no cutting towards yourself and keep those fingers out of the way... And again... check progress often.

Did I mention checking progress. If you remove too much, it won't be right and you'll be starting again... don't ask me how I know...
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Old Dec 29, 2006, 02:32 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Top's Next

Being very careful not to gouge out too much, I use the chisel to shave out the countour.
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Old Dec 29, 2006, 02:41 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
Rough in Complete

After rough sanding, and switching to 150 grit, it looks pretty good. At this point in the process, they're getting pretty delicate. With a little CA glue in the right places, they're not so bad. I have flown my Houston Hawks for over 400 hours and haven't broken a finished tip, yet.

If you look closely, however, you'll notice that one looks a little off colored at the very tip. I knocked it off right after finishing it and had to glue a little piece on...
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Old Dec 29, 2006, 02:52 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
7,793 Posts
About Ready

At this point, the tips really match the rest of the wing, needing just a bit of finish shaping and final sanding. It will be a while before I start the fuselage and empennage due to company, New Years, etc... Hope you're enjoying it.

Remember there's no shame in starting over on these if it's your first time... who's gonna know? Just take your time and be sure before taking any more material off. Also remember that this is the way I do this, and not the only way to do it. Experiment... you may be able to teach the rest of a thing or two. Just remember from the first pane in this thread... if you add a lot of beef... it'll fly like a cow...
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Old Jan 01, 2007, 11:00 PM
Hot Dawg Glider Pilot
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United States, TX, Weatherford
Joined Nov 2002
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Weight... up to now...

I was able to stack the completely finished panels on my postal scale today. It read 1 6.1. That's 22.1 oz. of not-finish-sanded wing. I figure to sand off more than I'll add with 2 spoiler blades. I still have to glass the center bottom where it will meet the fuselage, but that won't add much.

I haven't decided yet as to the fuselage sides. I really like the laminated sides that Ray uses on his Bird series, but they won't round out very well. I am trying to keep the aesthetics up on this ship... just because I like that in a model. I did find some 1/16" basswood at Hobby Lobby the other day that looked promising, but I want to keep it kit friendly. I considered rolling a plywood boom with some cf reinforcenment... between 2 layers of 1/64" ply... but I want the kit to be buildable for the average builder... so that's out... What's an old free-flighter to do?

Actually, the details are worked out, I just need to get on with it... You should start seeing fuselage / empennage details soon. I'm working up the fin / rudder and stab ribs this evening. The biggest problem with all of it is that I have to go back to work in the morning... and play catch up...

Jack
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Last edited by schrederman; Jan 24, 2007 at 08:57 PM.
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