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        Build Log A-1H Skyraider Build at 1/8th scale

#1 J Morgan Mar 11, 2012 03:22 PM

A-1H Skyraider Build at 1/8th scale
 
5 Attachment(s)
Decided I wanted to replace my A-1H( that DCobra has now:)) and do it in a larger scale too. This one will be 1/8th scale, 75" ws and ~ 58" long. Against my better judgement:rolleyes: it will have retracts, flaps, 4 bladed prop, and maybe even the capacity for dropping bombs. Would like to keep it around 8-9 lbs but it won't matter if I go over that, at this size it will handle a lot of weight.
I've learned from the previous two that I built that it is essential to keep the tail as light as possible. The short nosed Sandy can require a bunch of weight to balance.
Power plant TBD, I have several motors in the shop that would work I think.
We all know that foam airplanes don't like the sun. I have yet to find an easy way to protect them and using dark paints only compounds the problem. Only thing I have come up with so far is building the airframe in foam and then skinning it with balsa and glassing. I will use 3/4 oz glass/epoxy for finishing.
Let's get started:
I used a good 3 view and my overhead projector to make top, side, and front views of the Skyraider. It only had 4 cross sections so I will be relying on a 1/48th scale plastic kit for more information.
With all the foam fuses that I have carved and hollowed, I have yet to find the "best" way to hollow. A Dremel wire brush works and creates a heck of a mess, a soldering gun with copper wire works but stinks and is slow. Plus I've burnt up a couple of nice soldering irons using them that way.:rolleyes: So I wanted to use foam blocks to create the front portion of the fuse so that hollowing would be a minimum. Used the hot wire to square them up and then the fuse templates on each end to help with visualizing the carving of it.
Just got it sort of close and then hot wired it in half and hollowed out the middle.
Pics show how I started, I'm further along and will post some more progress shortly.
BTW, I don't expect this to be too quick a build as SEFF is coming up and I have some things to get ready for it so that will slow me down. Plus we will be at SEFF for 8 days.:)

J

#2 Wilfor Mar 11, 2012 03:36 PM

Cant wait to see this :D

#3 Waltjg Mar 11, 2012 03:47 PM

I'm here! Glad you got back home safe! :D w.

#4 peter24 Mar 11, 2012 04:28 PM

I feel another awesome build coming on, ill have to keep an eye on this thread, as no doubt it will be full of good info and ideas as usual. Keep up the good work j.

#5 matthew73 Mar 11, 2012 04:32 PM

Way to go J. Another great build to enjoy. I love the way you do your builds. Always giving me inspiration to try new things. Cheers.

#6 Willsonman Mar 11, 2012 06:43 PM

Subbed.

#7 docrob Mar 11, 2012 08:05 PM

This one's going to be a beast.....watching closely.
Best of luck with the build, J, and have an awesome time at SEFF.

Doc

#8 J Morgan Mar 11, 2012 09:50 PM

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Thanks guys. I'll try to keep it progressing until SEFF interrupts the build for a bit.;)

Hey Doc!
You have been much too quiet. Thanks, we will have a great time at SEFF. All you have to do is tell them that you have a seminar in Atlanta and hop on a plane. Sound plausible? ;):cool:

Moving on:
I used the hot wire to cut 1" thick pieces for the rear fuse section. Then using the side and top view, glued it up. Strengthened that section with a top horizontal bulkhead and left the bottom open for now.
Decided to make a FG cowl for it and I think I will make a mold for it. So I cut out two 3" thick foam cylinders, glued them together and used the drill press ( to make sure that it is perpendicular)to glue in a dowel. Spun the drill press and sanded the cylinder "nose". Made a foam sanding block the shape of the side view, it formed the cowl nose quickly. Used Dremel tools to cut out the cowl opening. Spackled, sanded it and checked for fit on the fuse. Now it is ready for glass to start the mold process.
More progress tomorrow.:)

J

#9 Sammy70 Mar 11, 2012 10:16 PM

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Looking forward to watching this one take shape J!

My uncle served our great country in Vietnam by working on Skyraiders, so I've always had a liking for these birds.

#10 gmwahl Mar 12, 2012 12:19 AM

Wow J, too cool! I have a skyraider also that I'm building right now. Mine has a 60" span to start and if it is a success, then I want to build a 1/5 scale one. It would have a 10' span and easily be the largest foamy warbird I can think of. I currently have the fuselage, wings and tail built, and was about to start the cowl. After seeing how you did the cowl plug, I think I will do the same thing, except I will use a giant plastic PET pickle jar and heat shrink a cowl for mine instead of fiberglass. I am excited to see another skyraider being done, and will be following this one closely!

Best of luck!
Mike

#11 FlyDave Mar 12, 2012 01:35 AM

Yahooooo , a new thread by John !

I can't start my day in office without a cup of coffee and the new posts on J threads :-)

#12 J Morgan Mar 12, 2012 06:25 AM

Our thanks to your uncle for his service Sammy.
Those poor old Able Dogs looked like they were rode hard and put up wet, don't they.

Good luck with yours too Mike. Feel free to post some pics of it if you desire.

Just be careful Dave, make sure it's on break times.:D

J

#13 J Morgan Mar 12, 2012 08:37 AM

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The rear blocks forming the top of the fuse are tack glued on. Once the shape is finished I will pull them off and hollow. Got to keep it light back there.

J

#14 J Morgan Mar 12, 2012 08:52 AM

5 Attachment(s)
Decided it was time to go to the wing center section so I could cut out the wing saddle. I hand draw all my airfoils. This one is a thick one just like the A-1 had and is semi-symmetrical. Hopefully that will help with a reduced need for down thrust on the motor. I love the Clark Y but with it's flat bottom increased climb with added power is a nuisance.
Drew the airfoils and made templates for root and tip ribs from 1/8" ply capped by copper tape.
Cut the blanks from two pieces of 2" white foam glued together with spray adhesive. I normally use 4" thick white foam but am running short of it. There is actually a plus to this way because the seam between the two gives you a clearly visible line around the blank. Saves having to measure and mark a 4" thick piece for the middle reference lines.
Cut the core and then sheeted with 1/16" soft balsa using Gorilla glue spread VERY thin.
Plenty of weight to compress the wing beds.
Once the center section was trimmed I used it to cut out the wing saddle in the fuse. The wing will be set at 1 degree positive.
I also have two layers of 3/4 oz glass on the engine cowl and will give it an add'l two coats of epoxy to protect it from the hot glue I will use to glue on the parting planes for the mold.
So this is where we are now.

J

#15 docrob Mar 12, 2012 09:50 AM

Quote:

Originally Posted by J Morgan (Post 21007554)
...

Hey Doc!
You have been much too quiet. Thanks, we will have a great time at SEFF. All you have to do is tell them that you have a seminar in Atlanta and hop on a plane. Sound plausible? ;):cool:

J

Heh :p, I'll give it a shot. Problem is, there's no "them". As the boss man, I have to lead by example :rolleyes:

Doc


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