RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Construction pictures,

Introduce the modern elevators of the reconstructed Oldest Taurus on Earth.
It is modern to use Carbon in your plane.
These elevators are filled with gaseous carbon, combined with oxygen in a well known combination.

No the real story of these elevators;

The LE of the elevators are made from 3 mm balsa plywood in which I drill the 3 mm hole for the linking.
Drill these between two hardwood parts and the hole is in the centre.
The TE of the elevators are filled with 1 mm plywood to make them sharp in the future.
Two “spacers” and a tip give the elevators rigidity.
The outside of the balsa sheets 2 mm I make some wet before gluing to keep them straight
I glue all the parts together and sandwich them one on the other between hardwood in a frame clamp.

The whole process looks time consuming but these elevators I can give a sharp backside and the weight isn’t more than massive.
Now it is modern the make the TE square, to enlarge the drag, but Ed didnot know I think!

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents,

Details of the elevator mounting of the Wester Taurus.

First picture , drawing of the cross section of the levermounting in the elevator.

Picture 2 and 4, checking the aligning of mounting.
To adjust the lineup I bend the piano wire ends

Picture 3 the flat top and bottom of the piano wire conform the holes in the elevator
For mounting the mechanic I use 2 component epoxy and binding wire.

BTW
Picture 2 and 4 are the quality control pictures to archive : HANNAPPROVED

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Very Stunteresque Wester.

I've done this on many models, works well!

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Hello Rendegade,

Yes, this is also my preferred method.

Next step is research the best I can use for the elevator pushrod?
First measurements, balsa, to get an impression of variation. The books give 2,5 % max length variation from wet to dry.
Variation depending of relative humidity variation of 60 to 90 % will be around 0,6 % length variation.
The temperature I measure also for the aluminum profile.
Length of the pushrod will be 60 cm 24”, so max variation can be 3,6 mm for the pushrod, and that is I want to know!

Hanna poes is watching the process of course. Measurement outdoor, next is indoor and steam the balsa

The second part of action is the material of the fuselage when the fuse is ready and then calculate the combination?
I will try to find out if it is possible to find a combination independent of relative humidity.

The varnish of the pushrod as show on the picture will be the last part to research.


To give an example of "wet" flight conditions I am in, some pictures I did take on 31 – 12 – 2007 flight picture, other Taurus in winter condition," Smoke on, light on!"
Hope you find this interesting.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents,

For who is interested,


I think Ed neither did use electrical tools so handmade motor bearers.
1 picture of process
2 inspection by Hanna poes
3 equipment and material

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

CAT Audit!

Sometimes Hanna poes does a audit (9001) of the CAD process of the OTOE.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents,

To glue the doublers on the fuselage sides I use vacuum bagging and control the vacuum on 0,4 a 0,5 bar suction pressure, 6 a 7,5 psi.

I use normal “white wood glue??”, but I make the backside of the fuselage side a little wet to keep the sheets “straight” and tape them together.
I make some pinholes in the corner of the bag in the fuse sides to delete the moisture by al little airflow through the bag. A lot of moisture also is exposed by the balsa of the sheets.

The Compressor is an old refrigerator compressor I also use for painting.

Picture 2 and 3 is the pressure controller, made from a bourdon manometer tube with electronic position detector, amplifier and a relay. Modern modelers will take a modern pressure switch I think, but you cannot use that for a Taurus.
Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents ,
Design considerations

In the early days 2,4 V for each direction of movement was used for the reeds but also first proportional servos;
Automatic reducing the speed and torque of every “door” movement.
So the generated forces in the linking of the controls also were automatic reduced.
Also the 45 K & B 0.45 didn’t pump much energy in the plane, the Oldest Taurus on Earth.

Prove?

Three threated hangings each aileron did the job of the Oldest Taurus on Earth, look at the crate picture.
But what happened after that?

One of the first modifications were the switched bridges for the electromotor of the servo so 4,8 Volt (around 1970?). So 2 wires to the battery and no differences anymore in unloading of the cells. Nearly 2 times the torque and 4 times the power, some extra losses by the semiconductors.
Next and not long ago the 6 Volt is used, so again 20 % more torque and 56 % more power available.
It is theoretical but the factor can be 6 times more power to the “doors”

Now we have new, high speed and high torque servos .

Of course there are pilots and planes that uses these power, but what about the Wester Taurus.
Look what’s happening with a high speed high torque “up” action of the elevator!

Picture 1 fig. 1.1 a snapshot of the twisting of the wing of the Oldest Taurus on Earth
In these picture we can see what is happening when the axle of flexibility is behind the point the lift forces affect. An old wing construction without a D tube.
Because this can happen in a glitch of the radiocontrol for safety I use the D tube.
It is not difficult to see that this can be the first movement of the wing followed by “flutter” in high speed conditions, because the angle of attack increases which enlarges the lift forces again.

Picture 2 fig.1.2 a snapshot of the twisting of the wing of the Wester Taurus with a D tube in the future.
The axle of flexibility in front of the lift force.
This is for me the second reason to use the D tube I did tell you before, we see the angle of attack decreases which reduces the forces.

This isn’t new, that’s why I also show a project of me, the Fokker D VIII, many crashes caused by the same problem during the introduction of the real plane in the first world war in 1918 by using the wrong dimensions of the two spars (front and aft) in the wing, and bad construction, so also a axle of flexibility behind the lift forces in certain flight conditions.
Also in this scale model 1 : 4 I will use for safety reasons the D tube.

So let us learn from the past and use a D tube in the Wester Taurus.
BTW this is all the way I think about this and explain on the most simple way, of course others will have another opinion I think.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents,

Reconstructing the Oldest Taurus on earth First didn´t show me much problems.
First I thought It would also have the long tail and the same stab.
But measurements later did show me the tail wasn´t long but short and the dimensions of the stab were about 85 % of the original. The area 72 %.
What to do?

First I thought I just use the same position of the CG on the wing just like the TF Taurus, and my own Taurus. But was that still the right position?
No I could not take the risk anymore.
I did do a simple check and show you the two pictures

First picture is the RCM E Taurus, the same as the Top Flite Taurus, so an original.
I did calculate the AC of wing and stab and the position of the neutral point (NP).
The distance between this NP and the AC of the wing is 145 mm.
The CG of the standard Taurus is on 23 % of this distance, on 33 mm from the AC of the wing.

Second Picture is the Wester Taurus.
The distance between the neutral point and AC of the wing is 83 mm.
The get the same stability the CG has to have a distance to the AC of the wing again of 23 % of the distance between the AC of the wing and NP.
For the wester Taurus this distance is 19 mm., so the Wester Taurus has to have the CG 14 mm more to the nose of the plane.
This is no problem to do, but important not to forget.
When I should use the position of the standard Taurus the plane would be half as stable but flyable and that is important to know.
During the first flights it is also important to know the position of the netral point.
Picture 3 is of my Orion, with the marks on the bottom of the wing


Maybe again we see the key of the success of the Taurus in the past, the enormous distance between the AC of the wing and the neutral point, you do have to make great mistakes in the position of the CG to make the plane instable, and so the fuel consumption did not change the stability much. and that all was important when flying with the reeds.
In that way of view the Wester Taurus is 75 % more critical to handle and trim, but again, maybe better for contest!

Thinking what to do with the position of the maingears, Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

IMHO, the mains should be positioned so that with an empty fuel tank, the plane will almost but not quite sit back on the rudder when the tail is pushed to the ground.

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

WEDJ,

We are going to use that, so first the drawing of the Standard Taurus to check.
The green dash is your :"almost but not quite sit back on the rudder" WEDJ, thank you that will do!
The construction drawings I will change the same way. But I will take a look if the wings were interchangable with the standard Taurus fuse then, just Ed did in Belgium?
Maybe hit did bent the maingear?
We will see!


Cees.

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Cees, If you are using the original RCM&E drawing to compare your T2 fuselage length, be aware that this Taurus is one inch (25mm) shorter than the Top Flite/Kazmirski Taurus. You should be able to use the same cg, percentage wise, but adjust the mainleg as WEDJ suggests.
Evan.

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Thanks for warning Evan,

The dimensions of my plane are all different from the other taurusses, TF and RCM&E.
The differences are more than I expected.
That’s the reason I do recalculate the CG again, the difference are too big to use the positions of the other planes.

In my post I did show you the way I do.

I need the indication of the calculated CG because I found that saver. And an better point to start. The indication of the neutral point gives me an indication what I do when adjusting the CG later and make corrections.
The calculation I do again when the plane is finished with all the real measured dimensions. That results I point on the plane like I show you the Orion.

For the Orion I did need this method because this plane is 10 pounds with only an ENYA 60 4C. With a deadstick the plane still flies.
With the CG on 25 % of the wing I am afraid it’s over.

For who is interested in scratch build constructions.
Retracts are always interesting and on the pictures of the Orion you cannot see much of it, I did find contructionpictures on my old computer, maybe it is interesting to show.
The legs ar highly modificated but the retract mechanisms are still the same. Spring and gravity return, 8 mm axles on ball bearings for each leg.
You also recognize the Taurus spars in the wing the retracts are directly bolted on. Spruce!! No balsa!! The bottom spar has a doubler for the retracts.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents,

Last pictures of the vacuum bagging.

I did need better plastic to prevent leakage.
The piece of textile prevents blocking of the airstream near the tube connection

The extra pressure vessel to get a smooth working pump, it lowers the frequency of switching.

Pressure during the first hour -0,5 bar, equivalent on 200 kg / 440 pound on my two little doublers, second hour -0,35 bar, last hour 6 pinholes on the bag around the plywood doublers to remove the moisture.
Last picture gluing the motor mounts against the fuselage side. In mirror image to check the alignment.
Near the engine room I use epoxy 2 comp. Near the tank compartment white wood glue.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Gents

The fuselage sides, prepared to build together with the formers I must make now.

May I also introduce you Quick Swim. From a home she wasn’t loved anymore. From a quick Fly owner.
Did swim all the way over the ocean to Europe.

Pet, don’t worry, Quick Swim already experienced she is loved here, especially by Hanna Poes.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

I use paper towels as breather material. I would place them over the wood and then draw the vacuum. No need to try to "control" moisture draw from the bag by pinholes in the bag. It happens automatically

MattK

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Hello Mattk,

What you write will be true,
Last time I did glue doublers the wood wasn't completely dry.
Before gluing I did make the sheets some wet, maybe too much,
This time I did use less water and the pinhole maybe are not necessairy then.
Some moisture, also on the side of the glue makes the process easier. It's a way of trying.
Results is always very good again this time.
I think Quality of the bag is important. In is important for the duty cycle of the pump not to overheaten.
What do you think Mattk is the plastic bag breathing with 0,5 bar pressure differece?
Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Cees,

You might want to go online to CST or ACP websites and look at their bagging stock. The tube is nylon, about 3mils thick but very tough. It comes in two flat widths, 18" and 30". Bags don't have to leak and theirs do not. ACP has a nifty way to seal them also. Losing 1/2 atmosphere of vacuum is not necessary.

Vacuum will naturally draw moisture from the wood and discharge it out through the pump. Breather stock helps do that better and is a must for even vacuum application without dead spots. This is especially true for wing skinning, to apply even lamination pressure to the skins

MattK

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Hello MattK,

That's all clear, thanks for info.
About the naturally way of drying through the pump is also clear. That probably has to do with the better evaporation under low pressure (evaporation pressure, dampdruk).
Wing skinning I never did but, maybe in the future? I will not forget.
I will look for the info.

For people who follow the thread, formers of the fuselage under construction and under quality control.
The firewall I made of three separate 3 mm (1/8) plywood so the spars/girders will not end in the engine room to keep them free of fuel.
I glue them later together to 1 firewall 3/8 thick.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Cees,

You can use vacuum to laminate the firewall. The applied pressure is extremely even on the whole face producing the best bond.

Don't understand why you need 3 layers of 1/8" ply. I typically will use one layer of 1/8" aircraft ply for fairly large firewalls and large engines such as Webra 160. Alliance has been around for 6 years and has 800 flights and Temptress 5 years and 1800 flights. Engines are soft mounted so maybe that's the reason

MattK

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Hello MattK

Why I use a laminated firewall.

First of all 3 mm plywood is cheap, I also use 1 mm but from a building marked just as 3 mm ply balsa. All the other balsa from the model shops.
Laminating also does not have disadvantages beside some more time to make them. I also try to be a perfectionist.

Pro is!

All spars and ridges will suck fuel when there is a little hole in the coating so a laminated fire wall (with fuelwall, see picture) protects these end grains against damage by tools in the engine room (for example that schrewdriver when mounting the nose gear), and the bottom of the fuse for FOD

Next point is the bottom bearing of the steerable nosegear has a better “background” for extreme forces towards the bottom of the tank compartment. The wing also has the same construction near his former so the tankbottom is between two formers.

Next next important point is, after a crash or damage the wood is less sucked by fuel and better reparable especially when using wooden engine bearers.
Most of the glue I do with 2 comp, so also the firewall has 2 fuel barriers inside.

When using a nylon or metal motor mount the fuelwall is the former in most forward position and protects also all the end grains also the fuselage sides against handling damage.
In that case during a crash it can be a profit the radio equipment is better separated from the backside of the engine because the fuselage sides are also behind the fuelwall.

These all are believable reasons, but maybe most important reason of all again , it is cheap, typical Dutch, 3 mm from the building market to make 6, 9, 12 mm plywood whatever I need, also in litttle parts.

What you say is always right MattK, a good mounted firewall of 8 mm that fit and constructed well is good for many years and flights.

A picture from my D VIII , an example of a fulnerable construction is which I can have much profit of a laminated wall.

I will use again the vacuumbagging and did that before, not for the Fokker!

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

[quotethe Orion I did need this method because this plane is 10 pounds ][/quote]

10 llbs !! Ain't that kinda heavy Cees. That gives a wing loading of 33 ozs/sq ft. The original Orion weighed 6.25 llbs for a loading of 21 ozs/sq ft.

Ray

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Ray,

When I did start building a second Taurus I also did think about making this with retracts.
The Orion was the taildragger so better to use for that experiment.
That’s the reason the dimensions are of the Taurus wing changed in the Orion wing with frise ailerons, the ribs were finished already on that moment of change.
The dimension of the fuselage I did change to get the overall dimensions of the Orion.

So it looks like an Orion, has the (wing) dimensions of the Taurus and a wingloading of a DC3.

I did weight the plane for you AND DID NOT TURNED ON ZERO ADJUSTMENT OF THE INSRUMENT.
Wing, nearly 2 kg, 1900 gram
Fuse with empty tank 2250 gram
Checkweight 2500 gram picture 3.

Total weight empty plane 4150 gram. Nearly 280 gram fuel makes 4430 gram is 156 ounce..
Wing is 4,796 sqft, loading is 156/4.796 = 32,5 ozs/sq.ft.

II love it to fly the plane and it has it’s restrictions but, the low drag of the fuse with the fairings and the retracted gear gives the plane enormous speed nevertheless the thick wing because his weight.
The engine also does not have any problem to pull the plane also not with the start. Keeping speed is than most important. Because of the heavy wings everything goes slow, rolls and turning , just like a real plane. The frise ailerons make flying easy but acrobat impossible.
Flying even with a deadstick is really no problem, when not possible to land on the field I make a belly landing.
The engine rocker hatch has a protection behind it for that see picture post 25.

The legs have the same suspension as the noseleg of my Taurus as I did show in the Ed Kazmirski’s Taurus, but a much heavier construction now..
I start and (always try to) land on grass with the Orion.
Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

Update
Interesting, ready with preparing the parts of the fuselage to assemble the fuse I read in the new thread “Old wise and skillful” a post from Tom: I'm not much of a handyman, but balsa doesn't really require 'woodworking' skills. It cuts like butter.(Post4)

Look Tom, it doesn’t require ‘woodworking skills’, but I do not know restrictions in using my tools. The metal grinding wheel to remove the “too much” wood from the inside of the outsides. When do it this way do it carefully!!

In the firewall the holes are drilled for the pushrods for steering and throttle, also in the former of the tank compartment
The fuselage sides are already bent in steam, it makes the job easier..
Formers are ready and the top is prepared so the tank has his place and the weight is reduced by removing some wood of the frame.

All the details are drawn in the construction drawing.

Next step is gluing the parts together. I allways take my time for that important activity.

Cees

RE: Redesign and reconstruction of the Oldest Taurus on Earth
 

For who is interested.


Mounting of the fuselage:

In steps from around 30 minutes.

1 most important is the right position of the firewall. The fuse wideness near the firewall is the same as near the first former. So the fire wall has to be square mounted.
BTW my vice I did find in the garbage some years ago.

2 former near the LE of the wing glued square.

3After some time the second fuse with 2 component on the firewall side again. Vertical in the vice to harden the two component of the firewall , NO PICTURE

4 harden and drying also the LE former on both sides

5 de result to dry/ harden for some time.

The 2 comp epoxy does harden in 10 minutes.

Cees