Slocum

Day 1

Welcome to my Colombo-Anderson Models 27% 300L building thread.

The reason I like doing these threads is that many people these days want to know what is involved with building kits. Many of them think building a kit is a insurmountable mountain. Some kits sure look that way when you look in the box at a pile of sticks. This thread will be broken down in days. These days, are days that I get to work on the plane. My average building session is about an hour and a half. Fortunately my family goes to bed early and I get a lot of sessions.

This kit in particular almost needs a class of its own. It has a bunch of very nicely laser cut plywood for the fuselage. And the wings and empennage are all foam pre-sheeted with balsa. The fuselage goes together like a 3D jigsaw puzzle and the foam sheeting saves a lot of time.

Today I got the box open and cut loose all of the plywood. The laser cutting was great! Step number two was to throw away the awful instructions and down load good ones from: http://www.marcelocolombo.com.ar/Ext...ual27ing_1.htm

The following is a direct quote from the originals: “-Fit with rod crossed of 6x8 mm between F6 and F7, F7 and F8, F8 and F9 in the inferior part and to cross in inverse form in the superior part (Photo24) Then, forming a cross between F6 and F7 because this is the zone of greater torsion of the airplane.” I much of that makes sense to you congratulations but what makes it even better is that it two typed pages with NO PHOTOS! That makes it kind of hard to see Photo 24. The web versions are MUCH better and have very good photos.

Then I got to epoxy the first parts together. There are three parts that are doubled plywood.

From what I have seen, of a friends birds, with sheeted foam wings they fly well and can take a beating that would destroy a built up wing.

To give you an idea of my experience with building here is what I have done so far:

Kits I have built:

OMP 80" Edge 540 Profile
http://www.rcuniverse.com/showthread...0&forumid=107&
OMP Edge 540 Profile
Balsa USA Force One
Tuff Flight Endro
Tuff Flight Predator
Combat Pig (3)
Great Planes Sportster Bipe
Great Planes Trainer 40


ARF’s

World Models P-51
Hobbico Twinstar
Morris Knife (Two, R.I.P.)
Hanger 9 Pizazz
Thunder Tiger Fun Tiger Extra

All photos are © 2003 Roger N. Slocum commercial uses by permission only. Much high resolution images are available..

Slocum

Here is all the foam.

Slocum

On closer examination of the instructions, the English is better but they are still greatly lacking.

At this point I have the sides together and the engine box sub assembly. Of course the engine box is clearly labeled left and right. I noticed when I saw left on the right side arg! I should be able to make it work though.

Slocum

This is the part that is just like putting a three-dimensional jig saw puzzle together. I found that using rubber bands on the bulkheads did a decent job holding most of it together. To help make sure that it was straight I put a piece of ¼ inch basswood in the center stringer hole. This made it a lot easier to see if it was straight.

Shortman

My Feedback: (21)

i love this! great information comes from people like you who take time to take pictures and explain it... im looking at there 31% for my next project

Slocum

Today was a shortened building session for two reasons.

First and best!: I wanted to make my plane a copy of the American Fire Birds Blue Fire bird. They have a nice web page at http://www.firebirdairshows.com but all of the photos are realitively small. So I was able to contact Jack Knutson, one of the pilots, and he sent me HARD COPY PHOTOS! This of course sent me scanning. I have posted the photos along with my build photos at: http://home.insightbb.com/~rogerslocum

Second I set up this page finally.

Tonight I got the bottom stringers on and one of the floors. The instructions make it sound like there is wood that will fit from F3 to the back. Since there wasn’t anything that long I spliced some. The rest tonight was very straight forward.

Thanks again Jack

SMALLFLY-

My Feedback: (19)

Hope your doing the red one. The blue one looks too much like mine . If I can find room I'll bring it to olney tomorrow. My 24% is ready

Slocum

I am doing the Blue one, CapThis was going to do the Red one.

MinnFlyer

My Feedback: (4)

Keep us posted Roger, it looks beautiful!

What engine are you planning to use?

Slocum

It doesn’t look like a lot got done, but it did. I put in the ¼” balsa bulkhead reinforcements. It is really surprising how this stiffened up the fuselage. Today’s photo shows a typical bulkhead with top and bottom ¼” square and side ¼” triangle. In trying to translate the instructions on this step I looked at all of the photos and noticed something. The next step, which is to put in diagonal braces between bulkheads, show the stringers off! It would make more sense to put them on after all of the braces are in. I should be able to get them in but it would be easier with out the stringers.

A note about instructions: Normally I assume that who ever wrote the instructions knows more about the kit then I do and I follow them very closely. Clearly if you do that with these, you are making a major mistake. Due to the quality of materials in this kit it should be easy enough that a first time builder should be able to build it. But due to the quality of instructions of this kit, I would only recommend it for a somewhat seasoned builder.

WreckRman2

My Feedback: (5)

Not trying to criticize your work however you don't need to add the 1/4 sq on the bottom and the tri on the sides to each former. The bottoms have the stringers to help strengthen them, the sides interlock into the ply sides so the tops are really the only side the needs the 1/4 sq reinforcement.

You also got to be careful not to get ahead of yourself. If you add those on the bottom you may not be able to set the rudder servo tray and the rx tray into the fuse bottom.

Your building it to fly not to withstand a crash so the less weight the better it flys.

Remember I'm not trying to criticize your work, I'm just sharing from my own experiences...

Also you are correct on the stringers... I wouldn't add them until everything else is complete on the fuse just because they are easy to break if not careful.

Great work and I look forward to more pics. I started covering mine last night.

rcavi8ter

My Feedback: (19)

This is what the 27% looks like all put together. I have about 9 flights on this bird and all I can say is WOW. I love this thing wgeffon flew my 27%, the prototype 31% and a recently completed 38% and he says they all fly the same. He says the 27% flies like a bigger plane than it is. I have flown the 31% and think it is just awsome. I have a ZDZ50 in my 27% and the flying weight is 13lbs. This is the best 3D airplane I have ever flown in the 80" span. I will have mine at the internet fly-in, in june and it will be all graphiced up by then. If you want to have something in the air quick that is not a cookie cutter ARF. This is the bird for you and they have it in 5 sizes so finding one to fit your needs will not be hard.

Chris Puckett

Slocum

Today consisted of putting the cross braces on the tail. This would have been easier for the bottom if the stringers were not on yet but I worked from the top and did the bottom first and did not have any major problems.

Snag Number 1: I was missing a piece of the 6x8mmx900mm balsa. Fortunately I had some stock and cut my own.

David on the bulkhead reinforcements, this is about the only thing in the instructions that has been clear. They say to do it. The construction photos show all of them except the bottom piece. This was not a crash proofing addition. I am a great believer in build to fly not crash but I try to go with the design the first time.

InsaneFoamie

My Feedback: (2)

HOW ABOUT SOME MORE BUILDING PICS.. OR ANY PICS OF THE 27% I'M WAITING ON MINE IN THE MAIL

WreckRman2

My Feedback: (5)

Here are some of my building pics, hope you don't mind me posting this in your thread.

http://www.********.net/caextra27



BTW, if your directions say to add all those extra tri stock stuff then maybe the changed the instructions and provided some tri stock do to if with. Mine said to do only the top and it didn't provide any tri stock either. Either way it's just a little extra weight if you don't mind it...

Slocum

Here is how the current instructions read:

"15. Using 6mm x 6mm balsa, reinforce the upper and lower part of each former. This is done by running the balsa from one side of the fuselage to the other, along the former. Remember to do this on both the top and the bottom.


16. Glue all the 6mm triangles to the formers and the fuselage sides, to reinforce them. "

If the instructions changed, Maybe there is a Reason!

otisflies

I have two different sets of instructions for my 31% that are quite different so it wouldn't surprise me if you guys had two different versions.

Slocum

I got to fondle some of the sheeted foam today. The turtle deck went on and boy does that balsa feel good, my wife should be jealous. I used wood glue and taped it down securely. I like to use strips of over long masking tape. This lets me fold over the end and make a tab, very easy removal results. Then I went to get my epoxy and found that I was effectively out. No problem I ordered some from Tower a while back and have not even opened the bag yet. It was hard as a rock! I went ahead and used wood glue to attach the cabin floor and hatch cover. That left me stuck for the night letting everything dry.

otisflies

Looking good. That photo is funny. I thought I was the only one who used that much tape! Here's a shot of the business end of mine so far.

Terry

SMALLFLY-

My Feedback: (19)

Roger. You will probably want to start saving for some taller gear. My 24% only has 1" of ground clearance and another thread says his 31% only has about 1 1/4" clearance. at the very least use a short tail wheel. it is taking long rollouts to get mine airborne

Slocum

Tonight was a major flash back to the late 70’s. Back in those days I flew a lot of .049 foam and balsa planes and there was no CA in my world. Five minute epoxy was king and let you build fast. I was back there again tonight gluing balsa to the side of the hatch. First I cut the balsa for the side but it quickly became apparent that the hatch would be too short. The instructions did not mention balsa on the back, but a close examination of some of the construction photos show some. I also used some plywood disks, left over from my last project, to make ears that will be how I will hold the hatch on latter. Tonight’s photo shows the hatch upside down from the back. I stopped at this point to let the epoxy cure so that the major sanding job that is coming goes well.

Slocum

Tonight I got to do about two hours of sanding, lucky me! The hatch was left blocky yesterday and needed to be sanded to match the ply bulkheads. First I epoxied the ply to the front of the hatch. Then epoxied the posts in that hold down the front of the hatch. After that I sanded all of the nice square wood in to curves.

A word about sanders. My favorite single tool is a Perma Grit sanding block! It has permanent sanding compound in the metal. One side is coarse and the other fine. This thing ROCKS! It can be seen on the table just to the right of the fuselage.

InsaneFoamie

My Feedback: (2)

is proving to be a tougher task to put in the 27% plane than i thought.

WreckRman2

My Feedback: (5)

Looking great...

One question, do you think using epoxy to glue everything will greatly increase the weight of the plane? I used Probond glue because I was scared epoxy would add alot of extra weight. The Probond is great but it sucks waiting 24 hours to make sure it is completely dry.

Slocum

The primary project for today was to create the hold-downs for the hatch. For some bizarre reason the designed method is to put a bolt in the center of the cockpit floor. That is right boys and girls, inside the canopy! Sure you could cut a hole in the top and drop a bolt in but that is not for me. I used side mounts. The photo below I think shows the method well.