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Old Dec 31, 2009, 10:45 PM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
Build Log
Lavochkin La-5FN

I've just started a build of a 1.2m span Lavochkin La-5FN. I intended starting it 12 months ago for the scale buildoff, but work got in the way. So the smell of balsa dust and CA is my Xmas present to myself.

Its going to have retracts and flaps. I've bought all the hardware:
Hacker A30-14L for power
3300 3S Zippy lipo
Spekrum AR7000 receiver
Hyperion mechanical retracts

I used 3-views from a russian website and drew it up with my trusty non-digital 0.3mm pencil. I also found some video from a Soviet training film which helped me get the shape right.

The target weight is 1150g which will give me 120 watts/pound and 14.4oz/sqft loading.

I've attached a picture of the colour scheme I propose. I'm going to attempt some scale weathering for the first time.
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Old Dec 31, 2009, 11:49 PM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
I started with the tail surfaces. Conventional built up construction to give a symetrical airfoil.

The wing is a classic D box structure. The pic shows the first panel assembled over the plan. Note the feet on every second rib, used to get the washout right. I'm using 2 degrees. Profili2 draws these feet for you. Most critical is having the washout right when you add the D box sheeting. Once that top sheet is glued on the washout is locked in for all eternity.

The airfoil is a Ritz 2-30-14 at the root and a 3-30-14 at the tip
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Old Jan 01, 2010, 12:09 AM
I eat glue
Canada, NS, Yarmouth
Joined Jul 2006
3,409 Posts
Very nice. Does this bird have split flaps?
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Old Jan 01, 2010, 02:20 AM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
That's the plan. They will just be made from 3mm sheet. Nothing fancy.
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Old Jan 01, 2010, 03:37 AM
UAS Pilot/Tech Instructor
CryHavoc's Avatar
United States, CA, San Diego
Joined Apr 2000
1,464 Posts
The LA-5 and -7 are one of my, if not my most, favorite Warbird. As far a Russian birds go they just look the part, down and dirty knife fighters. So, I'm always on the look out for kits and such.

I've got the HET-RC LA-5 kit as well as a WarbirdsRC LA-7. But, they are both a tad small for what I like right now and neither one have landing gear which my field needs. So when I recently stumbled upon this one, I ordered it right away;

http://www.cloudmodels.com/lavochkin.html

It'll be shipped out monday after the holiday. I don't know if I'm going to add flaps but I am going to add retracts and convert it to electric.

Good luck on your build,
Mike
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Old Jan 01, 2010, 09:20 AM
I eat glue
Canada, NS, Yarmouth
Joined Jul 2006
3,409 Posts
Just let us know when this one's available.
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Old Jan 02, 2010, 12:08 AM
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Glong-flyer's Avatar
Ballarat, Australia
Joined Jan 2007
347 Posts
Scaledown I like your line of thought with the Russian aircraft.
Mike, big call picking a favorite Warbird. The list is so long and so many things to consider. I still love the I-153 Chaika but then the Mig-3 but what about the I-16 Rata. Love them all.
Great subject and good luck with the build. I will be following alone for sure.

Pete
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Old Jan 02, 2010, 08:23 AM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
Cryhavoc
My brother has a Cloud Models Mosquito. Its a heavy plane because its got a lot of plastic, but it flies really well.

Pete
I seem to be attracted to Russian planes too. I've got an I-153, an IL-2 and a Mig 3. Perhaps its because they've got real combat credentials but they aren't over-represented on the flying field.

Here's a few more pics. The wing is coming along nicely. I'm trying to get a lot done this weekend because when I go back to work on Monday this build will slow down.
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Old Jan 03, 2010, 08:22 AM
Registerd Beaver
Smokin' Beaver's Avatar
Australia, WA, Warwick
Joined Jul 2003
3,564 Posts
Nice!
This will be a good one to watch.
I'd been wondering what your next one would be...

phil
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Old Jan 03, 2010, 11:28 PM
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WTFLYR's Avatar
West Central PA
Joined Dec 2008
2,140 Posts
I've always wanted to build an LA5 or 7. I sold my Alfa LA7, back when I knew I'd kill it. That was the last plane I should have sold, as my 190 is the best "grab and go" I have. Still, at this point I'm not adding ARFs to the collection, so an LA 5 or 7 build would be an excellent addition. I have no Soviet planes. A Sturmovik would be nice too, but the LA5 is better looking.

Your 3-view computerized pencil is my favorite building method. I've always said that a good 3-view with formers is almost a plan.
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Old Jan 05, 2010, 03:19 AM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
The Sturmovik has a generous wing area, so you can make it into a parkflier, but its not the prettiest plane. The La-5 has the big ugly air scoop on the top, but its the ugly bits that add character to a fighter.

Most people tell me I'm mad for not learning CAD. I'm just too lazy I think.
The biggest boon to the scale modeller is the prevalence of photocopiers that enlarge to any scale. I just take my three view drawing to work, type in the scale factor and run off a set of A3 sheets before the boss notices what I'm doing. I tape the sheets together and slide it under the translucent drafting film then trace my design over it. I often make the wing 5% to 10% oversize to lower the wing loading a bit.
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Old Jan 19, 2010, 07:27 AM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
I've done a bit more work on the wing. The flaps and ailerons are done including the servo installation. I bought a digital servo for the flaps which I programmed to operate slow. I won't know if the flaps operate at the exact same deflection until I glue the torque rods in after I cover the wing.
I'm installing the retracts now.
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Old Jan 19, 2010, 03:03 PM
Charged up and buzzing
vampire67's Avatar
Germany
Joined Aug 2005
531 Posts
Real nice contruction sheme.
Quite fast too

Quote:
Originally Posted by Scaledown View Post
I won't know if the flaps operate at the exact same deflection until I glue the torque rods in after I cover the wing.
I had some doubts but it might work if the angle of the rods corresponds with the angle difference on the servo attachment.

Quote:
Originally Posted by Scaledown View Post
Most people tell me I'm mad for not learning CAD. I'm just too lazy I think.
CAD is only helpfull when you want to cut parts directly with CNC.
3D is mostly a lot slower when using only moderatly priced systems and with the low training level of a hobbyist.

You seems to do well and quickly without computer, so why bothering.
The only benefit would be to get plans for publishing your designs.

Peter
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Old Jan 19, 2010, 03:10 PM
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WTFLYR's Avatar
West Central PA
Joined Dec 2008
2,140 Posts
Quote:
Originally Posted by Scaledown View Post
The Sturmovik has a generous wing area, so you can make it into a parkflier, but its not the prettiest plane. The La-5 has the big ugly air scoop on the top, but its the ugly bits that add character to a fighter.

Most people tell me I'm mad for not learning CAD. I'm just too lazy I think.
The biggest boon to the scale modeller is the prevalence of photocopiers that enlarge to any scale. I just take my three view drawing to work, type in the scale factor and run off a set of A3 sheets before the boss notices what I'm doing. I tape the sheets together and slide it under the translucent drafting film then trace my design over it. I often make the wing 5% to 10% oversize to lower the wing loading a bit.
Not at all. I used Pro-E for a number of years in mechanical design, but haven't found the desire to use it for model design. Sure it would be a good design enhancement tool, but the problem is that I would lose interest in building, if I were to sit at the computer. I like to get right to the balsa. Also, after enough builds, many of us can readily transform a 3-view into a design, and then a subsequent build, without the need for CAD. If anything, it's the design experience gained from designing with CAD, that helped reduce the desire for me to use it as a model design too. With a good outline, we literally form the design in our heads. For me, just the time spent getting the desired enlargement, printing, and taping all the sheets together is almost enough time away from the building table to cause me to lose interest in the build.
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Old Jan 20, 2010, 06:39 AM
It must have a machinegun
Scaledown's Avatar
Perth, Western Australia
Joined Sep 2004
1,267 Posts
I certainly don't have the skill to build straight from a 3 view (unless its a profile foamy!). I quite enjoy drafting, but if say I decide late in the design to move the wing back 10mm, there's an awful lot of lines I need to rub out and redraw. I presume that would be easier in CAD.
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