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79CJ
01-07-2010, 05:22 PM
I got a round metal cowl probably about 15 years ago and have had it ever since. I have finally decided to do something with it, so I got some free Camel plans off the internet and had them blown up 152% at Kinko's to fit the 4" cowl. The WS will be 31.9". I'm trying to build light, especially the tail obviously.

I am partly doing this thread because I think I'll have some questions along the way, I've never built a model without a kit before, so this is a bit new to me.

First question, I've never been happy with how the top wing attaches on bi-planes, it always comes off so easily when you just nose over on landing. How do you guys attach them? It doesn't need to be removeable, this will be small enough.

degreen60
01-07-2010, 06:17 PM
I got a round metal cowl probably about 15 years ago and have had it ever since. I have finally decided to do something with it, so I got some free Camel plans off the internet and had them blown up 152% at Kinko's to fit the 4" cowl. The WS will be 31.9". I'm trying to build light, especially the tail obviously.

First question, I've never been happy with how the top wing attaches on bi-planes, it always comes off so easily when you just nose over on landing. How do you guys attach them? It doesn't need to be removeable, this will be small enough.

I found a metal cowl from a Berkely Beaver I use to have. I filled it with plaster of paris and made a plaster master. Now when I need a cowl I put the master in the top of a 2 liter plastic bottle and heat shrink in the oven. Makes a light weight cowl and I can make all I need. I find it fits some ARF WW1 planes too. To attach the cowl I cut a piece of the foam that is used to make flat 3D foamies(tough and don't break) just slighty larger than the dia of the cowl, glue it on the front of the fuselage and slide the cowl over it.

I attach my top foam wing on my scratch builds by just cutting a hole in the wing and glueing the wooden strut in the hole. If it comes loose the wing is easy to glue back into place.

79CJ
01-11-2010, 07:32 PM
I am thinking of running a pull-pull setup because it is light and looks cool to boot. The rudder seems fairly straightforward, but I have a question about the elevator. Do you run a control horn on one side the elevator, and have both strings going to that one side, and have left and right elevators connected? Or, do you have a horn on each side and run lines to each side? If it is connected in the middle, this would be redundant and more difficult to rig.

Thanks.

degreen60
01-12-2010, 01:11 AM
I am thinking of running a pull-pull setup because it is light and looks cool to boot. The rudder seems fairly straightforward, but I have a question about the elevator. Do you run a control horn on one side the elevator, and have both strings going to that one side, and have left and right elevators connected? Or, do you have a horn on each side and run lines to each side? If it is connected in the middle, this would be redundant and more difficult to rig.

Thanks.

I have pull-pull on most of my WW1 planes. I no longer connect the elevator in the middle but have control horn on both sides. Here is how I do it. First I run about a 3 inch string through a hole on one side of the servo horn then under the servo attaching screw(may need a washer so it clamps the line) and through hole in other side of servo arm. I tie a bead in each end of the string. Tighten the servo arm screw clamping the string about in the middle. Now run a string from top side horn through one of the beads and to other top side horn. Hold elevators with just a little bit of up and even and tie strings to horns. Now run the bottom string the same way but through other bead. Now tie one end then pull tension in the lines and tie the other end, don't worry about where the elevators are. You don't need much tension. Now make the two sides of the elevators even, the beads let the strings slip. When even glue strings at the beads. Now loosen servo screw and set elevators level. If you need to retrim the elevator after test flight just loosen the servo screw and move the elevator and retighten screw. Don't worry, it still drives me nuts everytime I install the pull-pull keeping the strings from lapping over each other. Sometimes I have to install them and look down the inside of the fuselage to see if when I move one set if another set is pulled sideways. I also glue the plastic handle from a cotten swab in the fuselage for the string to run through. Its a lot of work, but is light and looks nice.

79CJ
01-12-2010, 12:44 PM
Thanks for the description, I think I understand the layout. So, in essence, there is a string from the top and bottom of the servo horn with a bead on each end, then the linkages to the elevator go through the beads so the upper and lower controls both form sort of a Y shape?

degreen60
01-12-2010, 03:34 PM
Here are a couple of pictures the pull-pull strings on my Bristal M1C. The outer 2 strings run from each end of the rudder servo arm to each side of the rudder. The two inside strings have black beads on them and run from each end of the elevator servo horn and have the two V lines from the elevator going through the beads. This does make a Y. I think you have the idea. Just make sure you glue the strings at the beads so they can not slip or your elevator will not work. I have bought some double ended horns but it is easy to make your own. I start with a square corner of plastic. Cut it into a 1 inch square. Cut out a 3/4 inch square leaving an L with 1 inch legs 1/4 inch wide. Drill hole in each end of the L. Lay the L on the control surface with the holes alined with the hinge line and that is how far back you want to install the horn. You want both holes on the hinge line when installed so the system is blanced. To be perfect the lines should run same angle from the control horn but I don't even try to come close to that. If you want that you need to install control horn at a 90 degree angle to a straight line from the servo to the hinge line.

79CJ
01-12-2010, 03:43 PM
Thanks for the explanation and pictures. They were both helpful. I've got a while in the build until I get to that part, but I didn't want to build too far so I no longer had access to what I wanted to do.

79CJ
01-18-2010, 09:30 PM
I've gotten along on the build a bit this weekend, so here it is.

I have covered the tail surfaces after I added some shape to them to make the ribs stand out at bit more. Saw that on here somewhere, thanks to whoever that was.

I have put together some landing gear as well, they are a bit beefier than the real ones, but with my landings its a necessity. They are made from basswood for added strength.

Finally, I have built all 4 wing sections and joined the top two. I just started covering, have to wait for it to dry to add more. For all the covering I'm using silkspan.

79CJ
01-21-2010, 12:37 PM
A couple more update pics.

79CJ
01-21-2010, 12:41 PM
I found a metal cowl from a Berkely Beaver I use to have. I filled it with plaster of paris and made a plaster master. Now when I need a cowl I put the master in the top of a 2 liter plastic bottle and heat shrink in the oven. Makes a light weight cowl and I can make all I need.

Can you explain your heat shrinking process? How hot, how long? How to convince your better half you're not an idiot for putting plastic in the oven?:D

degreen60
01-21-2010, 03:48 PM
Can you explain your heat shrinking process? How hot, how long? How to convince your better half you're not an idiot for putting plastic in the oven?:D

We been married over 40 years so my better half has known for a long time I am an idiot.

I wait till wife uses oven then before the oven cools I put my the masters in the neck end of a close fitting bottle. Set the back end of the master on something(I use old tin can) so the plastic can not touch the hot tray. I put it in the oven and turn the oven even hotter(400 to 500) and watch for the plastic to shrink(about 5-10 min) I make cowls ahead so I don't have to heat the oven just to make a cowl. If you make a master you can make other plastic parts. If you need a clear canopy you only have to make a master. You can use plastic cup(I haven't tried it yet) but understand you have to clamp the cup at the bottom of the mold or it will shrink upwards. I have seen a really nice cowl for the GWS Tiger Moth made from a cup. The pictures are of a cowl in a green bottle ready to be put in oven. A cowl out of oven and ready to be removed from plaster master. I cut the neck of this bottle off before molding to see if it formed better, answer no, leave the neck on. 3 cowls I have on planes made from one master.

degreen60
01-21-2010, 04:02 PM
If you leave the neck on the bottle you can use an aircompresser to remove the cowl from the master.

79CJ
01-25-2010, 07:04 PM
Thanks for the info degreen. I've made the plaster negative, and I'm about half way through a bottle of 7up to make the cowl.

When you painted it, did you scuff it up so the paint would stick better? The plastic seems like it would be smooth and flexible, both not conducive to paint adhesion.

degreen60
01-25-2010, 07:37 PM
Thanks for the info degreen. I've made the plaster negative, and I'm about half way through a bottle of 7up to make the cowl.

When you painted it, did you scuff it up so the paint would stick better? The plastic seems like it would be smooth and flexible, both not conducive to paint adhesion.

I just grab any spray paint I have on hand to paint the cowl. I don't sand it either. Some of my cowls do have paint spots missing where I had a ruff landing. If you use a clear bottle and paint the inside the paint is protected. I install my round cowls by cutting a piece of EPP(?) foam just slighty larger than the inside of the cowl and glueing it on the front of the fuselage. Slide the cowl over it for a tight fit. Makes the cowl easy to remove. On one plane I wrapped masking tape behind the EPP foam cause the fuse was smaller just enough the cowl would move.

79CJ
01-26-2010, 12:53 PM
delete...

79CJ
01-26-2010, 01:00 PM
Painting the inside is a clever idea, thanks.

I got some more work done, started building up the hump with paper and thin balsa. I used an idea from someone on this forum and made some vickers machine guns with paper and put ridges in the cooling jacket with a ball point pen.

7car7
01-26-2010, 04:05 PM
I used an idea from someone on this forum and made some vickers machine guns with paper and put ridges in the cooling jacket with a ball point pen.

hmmm, I have no idea what you're talking about. ;-)

Plane is looking great!

One thing that will help sometimes with paint adhesion is to spray the plastic with MEK or even Acetone, and just about imediately spray on a light coat of your paint. The MEK or Acetone softens the plastic, sort of eats into it. If you spray while it's still damp, then the paint will fuse into it.

Ron
01-26-2010, 05:24 PM
Nice job on the Camel............man I wish I could build small stuff like that..I'd have it crushed or broken every time I handled it during the build.

degreen60
01-26-2010, 06:37 PM
Nice job on the Camel............man I wish I could build small stuff like that..I'd have it crushed or broken every time I handled it during the build.

I built a DVII and a DR1 about the same scale. I keep breaking the balsa in the fuselage where I grip the plane to hand launch. With age I have lost some of the feeling in my fingers and probably cause of that I grip a lot harder than needed.

79CJ
01-26-2010, 07:04 PM
Yeah, 7car7, I have copied some of your ideas from your S.E. 5 to the best of my abilities. Thanks for the heads up on painting too.

It is delicate in spots and I have had my fair share of breaks while reaching to do other things. I have also punctured the tissue in a few spots, but it's super easy to fix. I imagine it's still far easier than a 1/4th scale DR.I!

I built Guillows and Comet kits when I was a kid with my dad, but I really haven't done any modeling in about 10 years. It is nice getting back into it, this scratchbuild allows me to be creative. Also, growing up and getting some patience works wonders on models. I built some control line profile models that were pretty bad when I was young. No sanding, just glue them tegether and throw some dope on them.

79CJ
02-11-2010, 01:11 PM
I have been waiting for some stuff to arrive in the mail to move the build along, and it got here this week, so hopefully I can start getting the electronics in soon.

Here are some pics of the progress - I had worked up the area around the cockpit some more and test painted some roundels and the tail. I am using water based paint which is a first for me on a model. One is a cell phone pic, so it's kind of crummy.

Ryan Flyer
02-16-2010, 06:07 PM
Nice Plane! I just started to build one from enlarged free flight planes. It is my firs balsa scratch build. Wish me luck!
Patrick

79CJ
02-16-2010, 11:33 PM
Great - post some pictures up when you get it going.

I have been busy lately so no progress, I hope to start getting the servos and stuff in this weekend though.

Ryan Flyer
02-17-2010, 12:11 PM
Ok I will. Its going pretty slow right now because I have to mod the plans for rc.

79CJ
02-23-2010, 01:04 PM
Camel Update. I put the servos in and hooked up the pull-pull for the rudder and elevator.

Biplane Murphy
02-23-2010, 05:14 PM
subscribed.

:)

79CJ
03-02-2010, 03:05 AM
Thanks to degreen I have molded my 1st cowl. I've still got to trim it up, but it looks good so far. I used the air compressor to get it off the mold, worked great.

I'm continuing to cover, getting around everything including the PP lines is taking a while.

79CJ
03-16-2010, 01:00 PM
It is coming along slowly, but surely. I have pretty much all the building done, now I am working on the detail work.

I bought some lightweight wheels and covered them with paper to make them look fabric covered, and then put them on a sprung axle. There isn't much give to the axle, but there is some, probably about 1/4".

I also have finished up the roundels and pained the covering white where the unit markings will be. It won't be 100% right, but I am going for the look of Billy Barker's early Camel. The underside is all painted as well.

Finally, I have installed some small aluminum tubing around the wing struts for the bracing lines to go through. That will probably be last so I don't break them all while working on it.

79CJ
03-28-2010, 12:29 AM
I've got the topside painted now. I tried my best for a good British green, it's a little light, but I'm happy with it.

79CJ
05-17-2010, 04:01 PM
Doesn't seem to have been much movement of the board recently, I guess everyone is out flying, hopefully having better weather than here.

Anyway, I've pretty much finished up the Camel. I'm pretty pleased with it, it's my 1st non-kit build. I'm learning to fly past trainers on my GP Fokker D.VII because it is A LOT tougher than this one. I'm getting better, hopefully I'll have the guts to fly the Camel by the end of the summer. It's easier on the stomach to crash an ARF than a homebuilt plane, you don't have the same connection with it.

I've put in a carstock Clerget that rotates with the motor, looks cooler sitting that running, can't really see anything but a blur. I've also hooked up some flying wires, finished painting, and made an access hatch for the underside. The only thing I'm not happy with it the paint. I wanted to use dope, but couldn't find anything but clear at any hobby shop. I guess they don't make it anymore? I ended up using acrylics, I feel like they turned out looking like I painted it with kids paint and it was very difficult not to make it look blotchy. Any difference in thickness is noticeable. I don't think I'll be using them again.

degreen60
05-17-2010, 05:39 PM
I would think blotchy paint would be correct for a WW1 plane. Most of mine are blotchy from crashes and painting only the repairs. Having a engine that rotates only shows when flying if the cowl is open at the bottom. I put the rotating engine in my Eflite Nieuports but desided it looked better attached to the cowl instead of the motor because of motor offset. My MS-L looks good with the rotating engine out the bottom of the cowl and I think my DR1 will too when finished.

Ryan Flyer
05-17-2010, 06:19 PM
Nice pics 79! I will be really happy if mine comes out half as good as that:)

7car7
05-17-2010, 08:38 PM
Love your landing gear! Wheels look great too. I saw the first pics of the tiny wheels, and was hoping you were going to change them!

Is it just the pictures, or is your top wing showing negative dihedral? (anhedral?)

79CJ
05-17-2010, 08:59 PM
Love your landing gear! Wheels look great too. I saw the first pics of the tiny wheels, and was hoping you were going to change them!

Is it just the pictures, or is your top wing showing negative dihedral? (anhedral?)

Thanks. Yeah, they were some spare Guillow's plastic ones I had lying around that I just threw on to get an idea of what it would look like.

Yes, it does have a bit of negative dihedral, but the wings are not exactly ridgid and when I lift it by the wings to balance it, the top wing straightens out. I feel like it looks exagerated in the picture, but there is slightly. It bothers me when I look at it, but I'm not sure there is much I can do about it now outside of removing the top wing and shortening the interplane struts. I think when I put the outer struts on I pulled the bottom wing into dihedral, and accidentially pulled the top wing down a bit.

degreen60
05-17-2010, 10:26 PM
If you shorten the landing wires it should pull the top wing flat. You will probably have to remove the flying wires first.

79CJ
05-18-2010, 01:20 PM
degreen - your suggestion would work if my rigging was more functional, but it is just one length on each side that is run through each strut. It's only under light tension to keep it taught.

Do you all think the slight negative dihedral will affect it's stability very much?

degreen60
05-18-2010, 03:09 PM
degreen - your suggestion would work if my rigging was more functional, but it is just one length on each side that is run through each strut. It's only under light tension to keep it taught.

Do you all think the slight negative dihedral will affect it's stability very much?


Sense you can lift the plane by the wing tips and the wing flattens I would think you could redo the rigging to pull the wing flat without much trouble.

79CJ
05-18-2010, 08:44 PM
Sense you can lift the plane by the wing tips and the wing flattens I would think you could redo the rigging to pull the wing flat without much trouble.

I think you're right. I'll give it a shot and let you know how it turns out.

hillbillynamedpossum
05-19-2010, 03:52 AM
Doesn't seem to have been much movement of the board recently, I guess everyone is out flying, hopefully having better weather than here.

Anyway, I've pretty much finished up the Camel. I'm pretty pleased with it, it's my 1st non-kit build. I'm learning to fly past trainers on my GP Fokker D.VII because it is A LOT tougher than this one. I'm getting better, hopefully I'll have the guts to fly the Camel by the end of the summer. It's easier on the stomach to crash an ARF than a homebuilt plane, you don't have the same connection with it.

I've put in a carstock Clerget that rotates with the motor, looks cooler sitting that running, can't really see anything but a blur. I've also hooked up some flying wires, finished painting, and made an access hatch for the underside. The only thing I'm not happy with it the paint. I wanted to use dope, but couldn't find anything but clear at any hobby shop. I guess they don't make it anymore? I ended up using acrylics, I feel like they turned out looking like I painted it with kids paint and it was very difficult not to make it look blotchy. Any difference in thickness is noticeable. I don't think I'll be using them again.


Take a look around this site. This dope runs about $22 a quart for colored butyl.
http://www.aircraftspruce.com/catalog/cspages/randolphcolors.php


Possum