Apogee Draco BG

[Simon Auty]

Went to Apogee site today to get myself a Draco BG.
Unfortunately out of stock and no indication of when they will be back.
To anyone who got one, I'd be very interested in a build thread.
Thanks in anticipation!

 

[kuririn]

Showing in stock now.
If you snooze you lose.

 

[Simon Auty]

It’s on its way -about half an hour after asking for a restock notification I got the email.
I ordered it that night.
Still would like to see a build thread.
Otherwise will post mine here

 

[Rktman]

Just read Apogee's latest newsletter (Peak of Flight #609) detailing the development of the Draco. There was far more concepting, engineering, testing and modification involved in the final iteration than I realized, and it gave me an increased appreciation for this kit. It's not just a cool looking BG or glammed up over-hyped glider. They really did a LOT of debugging and fine tuning to ensure this variable-geometry glider will perform reliably as well as being an impressive crowd pleaser. Give the article a read, it's fascinating.

Really looking forward to a build thread on this one, especially knowing the reason behind every component shape in the sliding mechanism, wings and booster coupling is for.

 

[TXJeff]

I've got one and am part way into building it. A brilliant design, excellent instructions. After the build comes trimming, so this won't be rushed to the oad.

 

[burkefj]

The design looks neat, priced more than the FF NCR F-117 retail price...... wonder how popular it will be.

 

[TXJeff]

I have been severely constrained by work-work... so the build is going very slow. I am at the exact half-way mark in the instructions: booster is done and I'm working on the wings.
I'll say it again - the design is impressive, brilliant - and complex. Kudos to the designer!
Before you start, read the instructions thru to the end, and then reference ahead as you build because it's not always apparent why some things might be as they are. This is a level 5 build, and don't second-guess the instructions. Measure twice and pay attention to the glue requirements.
Lay out all the parts carefully, use trays or some sort of containers to hold and classify all the parts. I lost two days because I thought I had lost two *tiny* nylon sleeves onto the floor.... actually I had marked them and set them aside and fortunately found them (and could not find replacements anywhere, which fortunately I didn't need once they turned up). My mistake, and my workbench now has a raised edge just in case.
What I don't know is how to prep the balsa wood - since my return to the hobby after 20 years off I haven't built anything with balsa fins - so I built a small Red Max with balsa fins just for learning purposes and had a warping issue (I wish I'd built it with plywood, like I did with my 4" Mega Der Big Red Max, because these inherently weak balsa fins will never last).
The fins here need a prep and paint; there are parts which slide against each other as the wings unfold and the instructions caution against potential friction or binding. The painting has to be done on some of the assemblies part way thru the build so I need to figure this out next. A wrong choice could wreck it so I will test on more balsa bits.
Next club launch is in a week and a half... it won't be ready, and it would be a mistake to rush it to the pad.

 

[Klatuso]

Well, a lot to process here. Assuming the balsa is extra thin, go with sand paper at 400 grit and higher with a light touch. Make it smooth like plastic. If you are worried about the strength of your fins you could "paint" them with thin super glue (thin CA glue). Before sanding or after, you have to sand and it can be tough. Patience. We tend to move faster than we need. And for the expense of this kit, I'm hoping it gives me weeks of exploration and contemplation in my rocket lab.

 

[TXJeff]

The design has several features to keep the overall weight lean yet strong. Here are stiffeners for the main win (overlay) and the stay wing (plywood insert).
If you read the history article that Apogee provides, you'll see the Draco was developed iteratively, with improvements at each iteration. Very impressive!
My build below is just at the gluing stage, no sanding yet. That comes in a few steps when an airfoil is to be added.

 

[Voyhager3]

I hope to see some good flights with these, there was a guy who “flew” one the other day.
It just banked over on take off, then slammed into the forest. It was a shame, he did a real good job painting it

 

[TXJeff]

Finally got some time to work on this. These are the 3 tail wings on the glider - as per the instructions, I am measuring the thickness as I am sanding.
Use of Apogee's sanding tools, both the T and the leading edge rounding tool, are a big advantage.
HELP NEEDED: this balsa is thin and when sanded is really thin in the trailing edges. What can I coat or paint these with to help strengthen them? Seems like the usual West System 105 would be too thick and heavy, and would curl the thin balsa. Or maybe Thin CyA on the edges, but that doesn't seem to add much strength.
I was thinking of using sand-able automotive etching primer to smooth these out, but that won't help with the strength.

 

[Rktman]

I use 50% thinned lacquer, a coat or 2 brushed on and sanded between coats. Soaks into the balsa and adds enormous strength.

 

[neil_w]

Or maybe Thin CyA on the edges, but that doesn't seem to add much strength.

In my experience thin CA greatly increases hardness, making the balsa much more ding-resistant.

@Rktman, how does the thinned lacquer compare to thin CA?

 

[TXJeff]

What brand of lacquer, and what thins it? Something I can get at Home Depot for example?
I'm all out of thin CA... not that I want to rush anything. 2 launches in the next week and a half should not drive my finish date... I keep telling myself that I know better than to rush this.
But the wings will be ready to on soon... so I need something to finish them with before that. Got to have it's paint or whatever before trimming begins.

 

[Rktman]

In my experience thin CA greatly increases hardness, making the balsa much more ding-resistant.

@Rktman, how does the thinned lacquer compare to thin CA?

Thin CA may be equally as strong or stronger. I find it more difficult to control and apply an even coat vs lacquer (it's basically dope) so I think it's more a matter of preference.

 

[Rktman]

What brand of lacquer, and what thins it? Something I can get at Home Depot for example?
I'm all out of thin CA... not that I want to rush anything. 2 launches in the next week and a half should not drive my finish date... I keep telling myself that I know better than to rush this.
But the wings will be ready to on soon... so I need something to finish them with before that. Got to have it's paint or whatever before trimming begins.

Minwax Clear Brushing Lacquer. Available at Lowes and Home Depot. Thins with ordinary lacquer thinner.

 

[TXJeff]

Excellent... will be buying this tonight and applying it to test balsa in the AM. THANKS!!!

 

[Rktman]

Excellent... will be doing this in the morning! THANKS!!!

If referring to lacquer, I'd suggest the gloss version, as it's better at sealing out humidity and moisture than matt. I've never had balsa warping problems with my gliders despite the high humidity here in the south during the warmer months.

 

[TXJeff]

The Minwax very very slightly warped the wing frame... but didn't warp the main wing or stay wing.
Wondering how I might unwarp it... . Don't know yet.
I already did a little sanding for the stay tie so that it slides smoothly.
Otherwise I'm prepping to assemble the wing mechanism, and simultaneously painting the body. After the paint then I will check the slide of the stay tie again.
This is a very very cool kit and challenging fun to build. Again, read the instructions, read ahead, don't try to rethink them, and read them again.
Last launch of the year is this Sat: winds forecast with gusts to 48, rain 25% and the wind in the wrong direction. So I am not rushing and will fly it in January. It's going to take some serious trim time anyway.

 

[Rktman]

If you've only added a single Minwax lacquer coat, a little heat from a hair dryer on the side away from the direction of the bend may allow any trapped moisture to escape, making the balsa shrink and rebend in the opposite direction. Place it under some weight after heating.

 

[TXJeff]

Apogee is about to release 17 assembly videos for the Draco BG, the first 9 next week. So I am going to stop here and wait until those are released and viewed. There won't be any opportunity here to fly it anyway until January.

 

[kuririn]

Assembly videos parts 1-9 are on the Apogee website now.

 

[kuririn]

Parts 10 - 17 are up.
Impressive product.

 

[CatServant]

I ordered one a couple of days ago and have watched all 17 parts of Apogee's build video series. I like how they used balsa only where weight savings were important and plywood where needed for structural strength. I'd be interested in a video on flight trimming of the glider.

 

[Cape Byron]

“Way too much glue.”

I like that Tim is as messy as I am with these things.

 

[JayB]

A Draco BG happened to be under the Christmas tree this year! Very excited to build it and also very glad that these videos are available before we take on the build.

 

[TXJeff]

After thinking about the *very* slight warping of the wing frame I described above, I proceeded with the next step which is to glue the wing frame to the body. I decided to not to use wood glue here, but instead JB Weld because the it is critical that it hold well (the alignment tabs are IMHO way too short)... which also should un-warp the very slight warp of the wing frame.
As you can see I am holding it very rigid for a day as it dries, having checked and adjusted it so that the frame is level. Also, I put the stay tie in now (rather than after it dries) as an additional check that the wing frame is parallel and that it can slide correctly.
At this point in assembly there is no going back, or correcting anything.
I'd recommend that anybody with better experience with balsa than I consider well ahead of time how you are going to finish all these balsa parts. I had tested some Minwax on spare balsa bits and only later found warping to be a problem on the wing frame (Minwax did indeed seal the balsa, which was the point of using it). But any more warping than what I had would be the ruination of the build.
Also - after Minwax and before that warped the wing frame - I painted all the parts their recommended colors. The wings are not perfectly smooth from a lot of filing and sanding for example. This is not show quality. That will affect performance.
And I really wonder how much my finished assembly will weight against other people's.
Building was a nice exercise, and as I said above follow the instructions very carefully and read well ahead. But finishing the balsa was above my skill level... I haven't done any balsa work since my original stay in the hobby in '68-70s. I knew how to finish balsa then (and inhaled a lot of balsa dope) and do not know how now. But then you have to (re)start somewhere.
I will say again, undeniably, the design of this kit is simply brilliant! Kudos to Apogee!

 

[TXJeff]

Wings on - now it gets dramatic and you can see that it is all going to work. Just need to add the stay wings next.
There is a little stiction from the paint... might use a little wd-40 for that. Of course the rubber band will overcome that but slight stickiness might add some time to deploying.


So, final assembly, a little paint touchup, fix the stiction, and then trimming it for flight. And launch next month IF the wind cooperates and the temp is reasonable. No rush.
Might slip in a Marco Polo GPS right at the balance point... give up some altitude in return for getting it back?

 

[Rktman]

Wings on - now it gets dramatic and you can see that it is all going to work. Just need to add the stay wings next.
There is a little stiction from the paint... might use a little wd-40 for that. Of course the rubber band will overcome that but slight stickiness might add some time to deploying.
View attachment 624166
View attachment 624167

Really looking great! The wingspan looks a whole lot longer in your shot than in the videos and static informational photos.

 

[TXJeff]

Stay wings still need to go on.
It's a fairly large glider and the lift of those wings will be significant. I'm really looking forward to trimming it soon (when it's warmer)!

How is everybody else coming with their builds?