Thread Tools
Jul 07, 2014, 04:57 PM
Registered User
dion9146's Avatar
Thread OP
Build Log

1/4 Scale Hols der Tuefel


Ok folks, this is a reboot of a build log I started a while back over on RC Scalebuilder.com. For various reasons of which I'm sure we have all been there, the build was side tracked on other things (including a growing business) that took away my time. But I have found renewed energy, a fairly clear work bench, and a desire to finish this thing. Plus, I figured by putting a build log on RCG where I spend most of my RC related online time, you guys would keep me honest and moving forward.

If any of you were following the build log over on RCSB, some of this early content will be a repeat, but I've finally gotten to a good place recently to reboot the effort.

So stay tuned for the Hols der Tuefel, my way.
Sign up now
to remove ads between posts
Jul 07, 2014, 05:06 PM
Registered User
dion9146's Avatar
Thread OP
After seeing the following video on YouTube and finding out what the little primary glider was called, I knew I had to build it. As you can see, the Hol's der Teufel is a closed cockpit variation of the good old German primary glider. It's been modeled before, but so have a lot of planes. I can only hope that mine comes in good enough.

Gliders and pilots (13 min 3 sec)
data_player

Luckily, I also found a friend here on RCG as a result of this thread. I am indebted to him an eternally grateful for the support, pics, and documents that he sent to me to get me started. . He was able to supply me with all of the documentation I need to get this build going including a CD full of detailed pics from his own 40% Primary glider build which is now hanging in a museum. I could not have asked for more or better reference material. Thank you Jim.

A little about me by way of intro. I live near Louisville, KY in the heart of no-aerotow country, but maybe ARUP and I can get something going now that there are two of us in the area. I fly with the Louisville Area Soaring Society. A great bunch of guys and a beautiful dedicated sailplane field, but nobody does scale or aerotow for that matter. I've never been a conformist anyway.

I love to build. Probably enjoy it as much as flying, so I'm really looking forward to continuing project. However, I also enjoy other hobbies, namely cycling and enjoying and working on my vintage Porsche. Those two activities usually trump my RC hobby. Oh yes, I also have two kids that keep me extremely active. And finally, I'm a Partner in a management consulting firm which means I'm either really busy and can't get to the workshop for weeks, or I manage to get lots done in large chunks. Either way, don't hold your breath during this build, you might not make it.

Just before putting the build on hold, I managed to have scaled the drawings to where I needed them, taught myself some cad and file conversion programs to help clean things up, and I started the wing rib build process.
Jul 07, 2014, 05:08 PM
Registered User
dion9146's Avatar
Thread OP
To start, I made a wing building jig. The 'frame' is cut out of 7 layer aircraft ply. Under the frame, I have a piece of white MDF shelving material, the rib plan, and a sheet of clear plastic typically used for spiral bound notebook covers. The frame is then screwed into the MDF board for a nice solid jig.
Jul 07, 2014, 05:13 PM
Registered User
dion9146's Avatar
Thread OP
I made a couple of different rib patterns dealing with the leading and trailing edges until I got it right, then started cranking out the ribs. This included building a jig for shaping the leading edge former for all of the ribs.
Jul 07, 2014, 05:21 PM
Registered User
dion9146's Avatar
Thread OP
And that's when things started to bog down. It's tough staying focused while trying to hand build 36 ribs with 4 variations on the same basic rib, but requiring different spacing, etc. And that doesn't count the ailerons yet. More on that shortly.

So the good news is that I finally finished the main set of ribs last night! Now I finally feel like I'm making progress.

Next step, the ailerons....
Jul 07, 2014, 05:32 PM
Registered User
dion9146's Avatar
Thread OP
And finally, to my first question. Why didn't I just build the ribs and cut out the ailerons later you might ask? Well, because of the extreme washout built into the tips of the original glider. As you can see by the attached drawings, the last 4-5 ribs gradually start to sweep up towards the tips providing a ton of washout. You can also see the same thing on some of the full scale pics of other SG-38 primaries, but then others don't have this extreme washout. Pics of the full scale replica of the Hols der Teufel seem to demonstrate at least a little of that built in washout.

I can understand this when it was used as a primary, sling it off of the hill type of glider, but should I also build this into my replica version as well? This isn't going to be a high performance sailplane in any sense of the word, but it sure would simplify some future build steps if I could just induce some of the normal washout into the wing assembly instead of building these ribs like this. Thoughts anyone?
Last edited by dion9146; Jul 07, 2014 at 05:46 PM.
Jul 07, 2014, 06:03 PM
Registered User
Hi Dion! I say 'go all the way' and build the special 'wash-out' ribs! BTW- I bought a tow plane!
Jul 07, 2014, 06:58 PM
Registered User
dion9146's Avatar
Thread OP
Sweet! What did you buy?

Never mind - saw your note on the other forum. Do I need to build floats for the glider too?
Last edited by dion9146; Jul 07, 2014 at 07:39 PM.
Jul 07, 2014, 07:15 PM
SAM Elec GrdChmp04,07,10,12,14
Jay Burkart's Avatar
Ok Dion,

I'm here and watching your building..........
wow built up ribs to start with!
Jay
Jul 07, 2014, 07:31 PM
Registered User
dion9146's Avatar
Thread OP
Hi Jay.

I know! If I would have started to build the fuse or tail or something first, I may have made more progress and stuck with it the first time. But I feel like I've finally climbed that Cat 2 hill and I'm starting the downhill run.

I waved as I rode by last weekend. How's the SAM world going?

Dion
Jul 07, 2014, 07:43 PM
You're serious, aren't you?
Aero Antics's Avatar
Its even more impressive when you get to see the parts up close!
More intricate than a lot of my architectural models.
Awesome work, Dion.

Allen
Jul 07, 2014, 08:32 PM
SAM Elec GrdChmp04,07,10,12,14
Jay Burkart's Avatar
Getting ready to go down to Clarksville next week for a 3 day SAM contest.
Built a new Wakefield model for the Electric Wakefield event, built Lanzo
'39 Classic, a bunch of sticks just like your Primary is.
I had a fellow SAM flyer call me about your Gull, R U ever going to get back to it?
Jay
Jul 07, 2014, 08:55 PM
Registered User
dion9146's Avatar
Thread OP
Uh, yes. The Big Gull. That almost made it back on the board before the HdT. But yes, I will get back to it after this one is complete. I promise.

Good luck next week!
Jul 07, 2014, 08:56 PM
Registered User
dion9146's Avatar
Thread OP
Quote:
Originally Posted by Aero Antics
Its even more impressive when you get to see the parts up close!
More intricate than a lot of my architectural models.
Awesome work, Dion.

Allen
Thanks Mr. president.
Jul 08, 2014, 06:36 AM
Registered User
dion9146's Avatar
Thread OP
Quote:
Originally Posted by ARUP
Hi Dion! I say 'go all the way' and build the special 'wash-out' ribs! BTW- I bought a tow plane!
Michael - me thinks you are right......


Quick Reply
Message:

Thread Tools