WattFlyer RC Electric Flight Forums - Discuss radio control eflight

WattFlyer RC Electric Flight Forums - Discuss radio control eflight (https://www.wattflyer.com/forums/index.php)
-   WWI Era (https://www.wattflyer.com/forums/forumdisplay.php?f=70)
-   -   Re-birth of an Albatros (https://www.wattflyer.com/forums/showthread.php?t=35856)

7car7 06-17-2008 06:25 AM

Re-birth of an Albatros
 
8 Attachment(s)
So, I had this poor little example of an Albatros DVa. It crashed too many times, was just too heavy for my skills I think.

Here's the full story of the original plane if you're interested.

I decided to give it a second chance.
Peter Rake was so kind to email me some .dwg drawings, and I put them into a drawing program and resized, and made a few alterations for my scale.

My original upper wing was 30 inches, and the new one is 32 inches wide. Of course the chord is larger too. And the lower wing is much larger than my original lower (it was not scale at all). I calculated a 10% increase in wing area.

I then gave the revised file to a friend at work, who just so happens to have a buddy with a lazer cutter! So we cut up the wings, and they went together VERY fast and quite nicely I must say. These wings were originally designed for a much larger Albi, so I changed the spars, and whatnot.

For the lower wing, I added a carbon fiber tube (1/8). I wanted some scale dihedral, so the carbon is split in the middle, and an aluminum tube was used to join them. The spars on both wings are spruce. I really wanted to use balsa, but decided to be cautious. I want the plane light, but don't want it to break when I sneeze.::o It's now at 1.6oz. (edit - 1.3oz, 36grams - must have been a typo.)

The ailerons will be pull pull, like the full scale, and will have one single servo mounted on top of the lower wing, with the horn underneath the lower wings upper balsa skin.

The upper wing is very light, IIRC it's about 1.6oz right now with ailerons. This is no covering. Upper wing is flat.

The whole rear of the fuse is brand new. I didn't like the old one, it was all plywood. Now it's all balsa, with a few 1/64th ply re-inforcements.
It has pockets for the vert, and the skid. They are braced to the outermost sections of the fuse. The fuse now weight 7.3 oz (with ALL the gear inside, except for the battery). Before I cut the whole rear off, and replaced it, it was at 7.7oz. (no covering, no tail group). Not a huge savings, but it is a bit more scale looking, and lighter, so can't complain.

The biggest benefit so far is of course the wings. Since I'd taken tissue and put it over the "monokote", they were pretty heavy. The upper alone was about 4.6oz IIRC. Without the servos.

There is esentially VERY little left of this plane that came with the original Cedar Hobbies kit. If I have one regret, it obviously would be that I didn't just start with a nice KIT from www.AerodromeRC.com or something similar. This build is such a scratch build at this point.

But I'm anxious to see it fly, should be a floater compared to how it was.

If you're still reading all this, thanks!
Chris.

Biplane Murphy 06-17-2008 02:30 PM

subscribed....:)

WWI Ace 06-17-2008 06:08 PM

Looks like you're off to a good start!! Steve

7car7 06-17-2008 06:42 PM

Currently I'm building the struts. Doing the cabanes out of 1/8 carbon tubing.
I joined them together using piano wire. Where there's an intersection, I take a piece of wire, (about 1 1/4 inch long) and bend an angle in it, about 3/16 inch long. Then the other end is bent over on itself, with a very tight radius. This tight radius gets pushed into the tubing that makes the Vertical part of a "T" connection. (hope that makes sense). The other end, with the short angle bend, is pushed into the horizontal part of the "T" thru a small hole drilled into the side of the tubing. The angle is needed so the wire can be inserted in the hole, then turned at a 90* angle to lock it in there. Then I glue everything together with thin CA. Oh, the tubing is "notched" with a small round file to make more surface area also.

Seem to work real well. I did this similar style with the plane before, but just for the ends of the tubing. I would take steel wire and twist it around something to make a ring for a screw to go thru. Then put the twisted part into the tubing. This time I'm using the stiffer piano wire, and just making a ring and puting both parts back into the tube.

This method is very light, in fact when I weighed all the new carbon struts together, they were lighter than the kit's plywood struts all together. But really, it's more for looks - they hardly weigh anything anyway. I'll get some pics of the struts next.

This project is going pretty slow really, I just work on it after the kids go to bed a few times a week.

WWI Ace 06-18-2008 12:51 AM

Sounds cool!! I would like to see the pictures of the assembly. Steve

scalercflyer 06-18-2008 02:09 AM

Rebuild
 
Excellent work. :D Nice and light! :) Just don't cover it red! ;) Martin

7car7 06-18-2008 03:23 PM

1 Attachment(s)

Originally Posted by scalercflyer (Post 426723)
Excellent work. :D Nice and light! :) Just don't cover it red! ;) Martin


Thanks! No, rest easy, there'll be no red. Probably do same scheme as last time - it was really cool looking when flying - lot's of contrast...

Percyflyer 06-23-2008 11:56 AM

Hey 7car7,

What paint did you use to simulate the wood fuse??

thanks
steve

www.hoosierdawnpatrol.com

7car7 06-23-2008 04:29 PM

replied in the other thread ;)

7car7 07-14-2008 06:52 PM

mini post
 
I haven't been very good at updating this, sorry. I always marvel at some of you guys that put a new picture up every day or so!

No pics yet, but very soon.

I finished building the tail group, came out great. Quite a bit lighter than the original scratch built tail group (that was very out of scale). I haven't covered it yet, but will soon, and I'll have some weights for that.

I covered the lower wing, and have covered the bottom of the upper wing. I'm using Silkspan and Butyrate dope. I sent the tissue through the printer, and put Lozenge patern on it. Very time consuming, and a pain in the but, but worth it I think. I'm not completely happy with it though. The colors bled quite badly, and because I'm not puting it over Mylar film like last time, it is very transparent. I also think the mylar (monokote type film) from last time helped to keep the colors from bleeding as bad. But it still has the basic look of Lozenge, and that's good enough for me. Has dark on top, and light on bottom. I think with the transparency, it will look all the same in the air, so I'll have to add some Chevrons to the bottom or something for orientation.

I must have had a typo earlier up above, because I said the lower wing was 1.6oz. It was actually 1.3oz, or 36 grams before covering. (Hope my scale isn't different each time, I'm starting to wonder - will have to test it. It's been consistent in the past.)

I sprayed the tissue with water, then tacked down the edges with dope. When the water was dry, it weighed 41 grams (1.4oz). Tissue added 5 grams to the lower wing. Then I finished the doping, and it still weighs 41/4.1. Kinda wierd. Perhaps there was some left over water in the wood, not sure. Point is, total covering job is Pretty light! I'll be treating this plane very gently in the hanger. I think some small wing tip skids are in order. Not scale, but I don't like torn up planes!

For those that have never tried using Dope on a plane, I highly recomend it, it's kinda fun, and has a great vintage look for these type of planes. Hope to get that upper wing done tonight, then I'll photograph them both, and get some pics up!

7car7 07-16-2008 03:00 PM

Latest pics
 
9 Attachment(s)
here's the latest pictures.

The tail group is made mostly of 1/32 balsa, in 3 layers, going different directions of course.
I just couldn't build them without puting the little raised strips on to give it some shape.

The V struts are made of 1/32 plywood with 1/16 balsa attached to both sides.

The underside of the upper wing shows where the rigging will be attached. At the cabanes, I used wire, going through the spars, (last photo) and on the outer ends, I used Polyester wipping twine (very strong stuff) tied in a loop, and going around the spars. You can see that in the second to last picture.

So, as you can see, the covering is very transparent, but when viewed at an angle, you almost can't tell. Fortunatly, only the lower color seemed to really bleed. Top didn't seem to as much.

The original LOWER wing was 1.9oz, this new one is about 2 inches longer, and weighs only 1.4! I'm getting very excited to see this one done.

I'm very happy with the covering job, hope ya'll like it!

scalercflyer 07-17-2008 12:04 AM

Very Sweet! :D Excellent job Pal! :) Keep it coming! :cool: Martin. BTW, I NOTICED!

7car7 07-17-2008 02:28 PM


Originally Posted by scalercflyer (Post 442830)
Very Sweet! :D Excellent job Pal! :) Keep it coming! :cool: Martin. BTW, I NOTICED!

Thanks! I'm all better now, done whining!

Percyflyer 07-17-2008 03:11 PM

Good looking Albi. BTW your paint process was way too complex for me. I'm lazy. But I did come up with a brown at a craft store that will be close enough and I can add darker streaking to simulate the grain and think it will come out OK. Your Albi fuse looks great!!

steve

7car7 07-17-2008 08:28 PM


Originally Posted by Percyflyer (Post 443130)
Your Albi fuse looks great!!

steve

Thanks! I get to do it all over again! Should be fun.

7car7 08-08-2008 03:11 PM

Another round
 
6 Attachment(s)
Here's another collection of shots.
Doesn't seem like I'm getting a lot of progress, this plane is taking forever! But I am getting approximately 1 hour per night on this thing believe it or not!

I had to completly rebuild the horizontal stab, this is now the THIRD ONE I've made for the rebuild, so I guess you could say it's the FIFTH one this plane has seen!
The second one, after doping, turned out like a "Pringel" Potato chip! I think the combo of the thin outer frame, and lack of spar(s), well, it was weak. The new one came out VERY strong, and, amazingly, same weight as the second one.
This new one has a wider 1/16 thick outer frame, and I used carbon fiber tubing (1/8) as spars. The rearward one with the "V" shape has a short (about 3/4") piece of wire bent to the shape, then glued inside. This "V" puts the spar into the stronger/thicker part of the rear of the fuse, and it helps with the airfoil shape. The ends of the tube are notched, and clamped down to the outer rim to make them flat. No twist, whatsoever!
Whole stab with covering and paint is 10 grams. Not super light, but I'm happy considering this is a very hard shape to get light. Square frames are easy and strong.

The fuse is mostly painted now, and I have yet to do the gray around the nose and engine. But I wanted to show the wood finish. The fuse is covered in Silkspan, (like everything else), and then given the wood look treatment. It's slightly darker than what I wanted, yet I've grown to really like it this way - looks more like an antique plane, rather than a brand new - from 1917 - plane.

Last pic is the cabanes. I mentioned them earlier, but never gave a photo - they're carbon tubing, with piano wire "hooks" put inside to lock everything together. Need to paint those too.

Thanks for looking!

scalercflyer 08-09-2008 03:52 AM

Excellent
 
Excellent work 7car7! :) Keep the pics coming. Martin

WWI Ace 08-09-2008 09:30 PM

I like it!! Steve

7car7 09-02-2008 06:10 PM

10 Attachment(s)
Well, it's ready to fly. After crashing my SE5a, and finally fixing it, I'm going to warm my thumbs up on it before I send 3 months averaging an hour per night up in the air.

Still have some little details to work on, like a cockpit padding, and of course the pilot, and a re-do of the nose area painting. I want to eventually put some pilot artwork on too. But most important, I've GOT to replace that engine and guns - don't quite live up to the level this plane has become IMHO....

First 2 pics show the single servo PULL PULL with differential. I was told "It won't work" "can't do that" etc... Well, it does work. No slop, no binding.
Pic one shows at rest, Pic 2 shows at full aileron. Any questions on that, just ask.

Third thru fifth pic shows the deflection of the ailerons - more up than down. Note the washout.

Sixth shot shows the wheels. I took light foam wheels from Hobby City, and applied paper cones to them. They have a hub of carbon fibre tubing.

7car7 09-02-2008 06:32 PM

more
 
8 Attachment(s)
some more.

Covered up the aileron servo with tissue and dope - shouldn't need in there again - I hope.

Some details showing the rigging and aileron pull-pull setup.

barmonkey 09-02-2008 10:17 PM

Fantastic work and engineering on the Aileron control. It's hard to believe that it's the same Plane! Well I guess 30% of it is...

Are those wheels the yellow ones with five spokes? Those wheel covers look great.

I hope you have better luck with it this time around!

7car7 09-02-2008 10:22 PM


Originally Posted by barmonkey (Post 467752)
Well I guess 30% of it is...

Thanks! I'd think more like 10% if that! Really only about 3 inches of the fuse where the cabanes attach! All new forward and aft, and outboard, and under and over that part!

scalercflyer 09-03-2008 11:06 PM

Cockpit coaming
 
7Car7/Guys here is a neat way to make great looking real leather cockpit coaming. I save old shoe tongues and well worn wallets for the thin leather they contain. Figure out how long a piece/pieces you need. Cut the leather into thin strips. If needed stuff with a small piece of fuel line tubing or something similar. Start sewing the coaming to the sides of the fuselage with wide stitches. End up with a stitch or two on the end if needed or tie together the ends. Study pics of the real thing for more detail. This method produces a really cool cockpit coaming. Martin

scalercflyer 09-03-2008 11:09 PM

DVa
 
Beautiful work 7CAR7! The Albatros is my next favorite German fighter next to the DRI followed by the DVIII. Can't wait for the flight report. Martin

WWI Ace 09-03-2008 11:14 PM

Very nice rebuild!!!


All times are GMT +1. The time now is 03:49 PM.

Powered by: vBulletin
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.

Page generated in 0.06817 seconds with 7 queries