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Old Jun 13, 2012, 09:55 PM
That's so classic you.
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United States, NC, Stokesdale
Joined Jul 2006
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MK Skymaster 20 build

I've always wanted to build one of these little jems. I was able to work a trade here on RCG and now I have one on my bench.
Power will be an OS. 25VF DF, special Hatori header and a Macs 1220 muffled pipe. Retracts may or may not be Eflites as I'm not sold on thier reliability.

Comments and suggestions welcome.
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Last edited by Generic Member; Jun 13, 2012 at 10:01 PM.
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Old Jun 14, 2012, 01:09 AM
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Great find!
Are you planning a build thread?


DM
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Old Jun 14, 2012, 06:37 AM
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United States, GA, Alpharetta
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A nice find indeed. Have fun.

David
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Old Jun 14, 2012, 08:45 AM
That's so classic you.
Generic Member's Avatar
United States, NC, Stokesdale
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Quote:
Originally Posted by AURORA60 View Post
Great find!
Are you planning a build thread?


DM
Yes Sir!
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Old Jun 14, 2012, 08:49 AM
That's so classic you.
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United States, NC, Stokesdale
Joined Jul 2006
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Instructions

A very nice gentleman sent me a scanned copy of the plans which saved me a trip to Kinkos.
The "instructions" are isometric views of each assembly step with some writing in Japanese which I'm sure just says "glue these parts together as shown".

I made jpegs of each assembly step and printed them out for easy reference.
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Last edited by Generic Member; Jun 14, 2012 at 01:34 PM.
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Old Jun 14, 2012, 08:50 AM
That's so classic you.
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United States, NC, Stokesdale
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Wing

Wing and stab.
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Old Jun 14, 2012, 12:54 PM
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Joined Mar 2004
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Had one back in 96', one of my smoothest 25size patternship. Flown with an OS25FX w/9x6 APC, mini servos and fixed landing gear.
I remembered I placed a 1/64 ply doubler on fuse sides for added reinforement. Good luck on your build!
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Old Jun 15, 2012, 10:35 AM
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Yes! This is going to be one sweet looking little pattern bullet.

Jeff, remind me, are the tank front and rear formers the same width? I seem to recall they weren't but they must be. Is the 25 VF a drop fit on to the bearers? I didn't get to those measurements yet.

Coming along quickly!

David
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Old Jun 15, 2012, 11:01 AM
That's so classic you.
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United States, NC, Stokesdale
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David,
Formers F3 and F4 are the same width. I haven't tried to fit the 25VF yet. This weekend I'm planning on finishing the fuselage assembly including fitting the engine and nose retract.

I need to pick up some fuel and a coupler so I can bench run the 25VF.

Looks like I need a new camera. The pictures look fine on the camera display but look odd once posted.
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Old Jun 15, 2012, 11:26 AM
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Originally Posted by Generic Member View Post
David,
Formers F3 and F4 are the same width. I haven't tried to fit the 25VF yet. This weekend I'm planning on finishing the fuselage assembly including fitting the engine and nose retract.
Makes sense. You wouldn't have built the fuse that way if they weren't. I guess it will be time to revisit the plans over the holidays. Hopefully I can get things finished up.

Have you settled on the etracts for the time being? You could always refit 602's later if you decide against the etracts. I'm pretty sure the rail width in the wings would be the same.

Quote:
I need to pick up some fuel and a coupler so I can bench run the 25VF.
What fuel do you plan to run? #8 plug? 8x7, 9x6? It's gonna be loud!

Quote:
Looks like I need a new camera. The pictures look fine on the camera display but look odd once posted.
Yea, the white balance looks a little off. Maybe not a great sensor. Some of the phones take great pics these days but they cost more than actual cameras. The Canon and Sony cameras have good sensors - nice warm colours.

Are you building on cork on a glass top? The material under the fuse looks unusual.

David
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Old Jun 15, 2012, 01:16 PM
That's so classic you.
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United States, NC, Stokesdale
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Quote:
Originally Posted by doxilia View Post
Makes sense. You wouldn't have built the fuse that way if they weren't. I guess it will be time to revisit the plans over the holidays. Hopefully I can get things finished up.

I attached a jpeg of the F3-F4 formers.

Have you settled on the etracts for the time being? You could always refit 602's later if you decide against the etracts. I'm pretty sure the rail width in the wings would be the same.

I'm going ahead with the Eflites.

What fuel do you plan to run? #8 plug? 8x7, 9x6? It's gonna be loud!

I'm going to use PowerMaster 15%, OS 8 plug, and a 8x6 MK Glass prop to break it in, then either the 8x7 or 9x6 MK Glass prop. I'm guessing the .25VF DF can spin the 8x6 well over 18K. Loud? Yeah, and FAST!


Yea, the white balance looks a little off. Maybe not a great sensor. Some of the phones take great pics these days but they cost more than actual cameras. The Canon and Sony cameras have good sensors - nice warm colours.

Are you building on cork on a glass top? The material under the fuse looks unusual.

My bench is 3/4" ply with 1/2" glass. I have a pressed fiberboard (ceiling tile) on top.

David
Response in blue.
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Last edited by Generic Member; Jun 15, 2012 at 03:11 PM.
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Old Jun 18, 2012, 09:51 AM
That's so classic you.
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United States, NC, Stokesdale
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More fuselage work.

Made quite a bit of progress on the fuse this weekend.
With the exception of mounting the deck (because I haven't got it back from Don yet) and mounting the tail feathers, the fuse is more or less complete.

The OS .25VF DF fits perfectly between the engine mount rails.

The plans show a MK 150cc "oval" tank which was not included in my kit. I noticed Singpore Hobbies lists that particular tank, but when I went to order it, it's not availible to order. I just happen to have a Tettra 150cc "crank tank" in my box of fuel tanks, so I'm using it. I had to make some minor modifications to the F3 bulkhead. For some reason I had a number of different mfg's 6 oz tanks. None of which would fit with the exception of the Hayes 6oz "slim" and the Tettra.

I'm going to wait to do any more sanding and shaping of the fuse until I get my deck back.

The Eflite 15-25 size retracts are a perfect fit. The only down side is the length of the "servo" lead. I'm going to open them up and solder on longer leads.

The spinner in the photos is a 2" which is slightly oversized. A 45mm spinner is listed on the plans so I'll need to order one of those.

Not shown in the photos are the throttle and nose wheel steering pushrods. I'm going to mount the servos (Hitec HS-82MG's), before I set the fuse aside and work on the wing.
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Old Jun 18, 2012, 10:37 AM
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Outstanding work as always Jeff.

It's good to see that the Macs muffled pipe fits nicely on the fuse top even with no header trimming. I suspect that with the 9" props little if any header trimming will be needed but perhaps you'll prefer running the higher pitch 8" props.

The Hayes slim 6 oz tanks are a key fit and replacement for the 150cc MK tanks in many of the MK 20 size kits. The 6 oz are also a better volume when using 32 size engines on the larger models (e.g., Aurora, Cosmos). I redrew formers pertaining to the tank area using the Hayes tank. It's good to see that the Tettra is also an option as none of the other 6 oz tanks seemed to work being either too wide, too tall or both. I also modified the nose formers slightly to allow more convenient use of 2" spinners in the "imperial" plans.

The short leads on many of the etracts are a little inconvenient but on the other hand they keep the coupling connections in a more easily accessible area. The three lead connector should be long enough to connect to the nose gear as well as the receiver. The main gear on the other hand would benefit from the single long leads you mention so they exit the wing top center and can connect to the forked lead with a single connection (well, one per unit).

By the time you are done with the wing and gear installation, hopefully Don will be finished with the mold.

Are you thinking of painting fuse and deck or deck only?

David

PS You got a new camera!
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Last edited by doxilia; Jun 18, 2012 at 11:51 AM.
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Old Jun 18, 2012, 11:03 AM
That's so classic you.
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United States, NC, Stokesdale
Joined Jul 2006
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Thanks David.

I decided to go ahead and lengthen the servo lead for the retracts. The process was pretty painless and only took about 30 min. I didn't like the nose retract connector residing under the fuel tank. Now it's long enough to make it back to the radio compartment.

As for finishing, the wing and stab will definitely be Monokote. I haven't made up my mind in regards to the fuse. I know the deck will need to be painted. I plan on more or less going with the box art for design. The problem with painting is getting Monokote matching paint. If I'm just painting the deck, it's just white and what ever color I want to use for the "canopy". The fuse has white, red and dark blue. On a positve note, none of the colors on the wing, touch the fuse so a less than perfect color match wouldn't be noticeable. I could also substitue black for the dark blue which would only requre a matching red.
Lots to contemplate.
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Last edited by Generic Member; Jun 18, 2012 at 11:06 AM. Reason: Added retract modification photos.
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