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Old Jun 06, 2011, 06:07 PM
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Twin Het 700 motors, next to almost identical Neu 1515.

The above Neu is a warranty replacement, the original 1515 had a defective stator, shorted out in my MiG-21, set the 120A controller on fire and burned part of the tail section of my MiG, including most of the tail wiring. The Het 700 that replaced it has worked fine so far in the MiG-21

Motor weight is roughly determined by required continous power under very good cooling conditions, 2500W / (7 W/g) = 360g approximately, which puts it in the 700-68 class.

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Old Jun 06, 2011, 06:09 PM
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Twin 90mm fans ready for installation in the Me-262,

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Old Jun 08, 2011, 02:51 PM
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Thanks to Thunder's excellent picture of the AW fan formers, I should be able to make some progress quickly in the fan installation department ...

The elevator and aileron servos are finally in and tested. The elevator servos are mounted asymmetrically to avoid the use of mixers or mixing functions in the transmitter. A single y-connector is used in the tail, as well as one for the ailerons.

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Old Jun 09, 2011, 07:30 PM
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These brakes are hydraulic, and require a specific type and shape of wheel inset. Not sure I will be using these particular designs; well made and lightweight but not necessarily a good fit to the Robart rims & wheels ...

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Old Jun 09, 2011, 08:42 PM
Lee Liddle
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I've noticed that some hydraulic systems are starting to be offered. They will probably be easier to make work smoothly because the pressure variation will be more exact with fluid as opposed to air, but can you imagine the mess if you get a leak? Also normal brake fluid is very corossive and will remove paint. Could get ugly.
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Old Jun 10, 2011, 02:55 PM
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Cool project.
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Old Jun 10, 2011, 06:01 PM
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Yes in principle hydraulic brakes should be much smoother because of the incompressibility of oil (some even use water, but does not seem a such a great idea to me since it evaporates).

I thought though this was more an internet flying kind of project, but then my friend Gregg F has oil brakes in a BVM Fury and he says they work fine. If Gregg says they work, then they work ! I suppose once you put the oil in, you are done for life...

They work quite differently from the BVM and Robart Uni air (pneumatic) brakes, which make an o-ring expand against the rim. There when air pressure is released, the o-ring returns to it's previous state, hopefully unlocking the brake.

On the other hand the above oil (hydraulic) disk brakes rely on the servo activated piston to push in, and then pull back the disk away from the wheel.

I noticed a number of things:

1) The brakes are made by UMS where you can see what a full system entails , http://www.umstech.in/view_products....ssories&page=3

2) They say on RCU 3-in-1 oil, or jack oil, works fine (I suppose it's ok with the o-rings).

3) The plunger can be made very simply with an insulin syringe, or use the smc one with a strong digital servo. Each brake has an air purge valve. Filling the brake circuit sounds like fun.

4) I am not sure what wheels fit these brakes, besides the UMS 90mm ones. It's not clear to me that the Robart aluminum hubs will work. The brakes apparently need 55mm rims.

5) I am thinking of just ordering a pair of UMS alu hub 90mm wheels, so I don't have to figure out how to fit the wheels to the brakes.

6) All of the above makes the Robart Unibrakes look very attractive in spite of the price .

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Last edited by Herb; Jun 16, 2011 at 03:38 PM.
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Old Jun 10, 2011, 06:28 PM
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Hello Herb,

Thought you might appreciate these pics I got today. Not something you usually see on the ramp at your local airport. Apparently this is the 262 that was donated to the Collings foundation and they are flying off the time required by the FAA here in Sacramento!

-hutch
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Old Jun 10, 2011, 06:47 PM
Lee Liddle
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Three and one oil would be much more user friendly than automotive type brake fluid. That would be nice to have proportional brakes instead of the almost on/off function of the air brakes. You also have plenty of room inside the plane to be able to access the system if you ever needed to.
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Old Jun 13, 2011, 04:07 PM
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Hutch, thanks for posting the Me-262 twin seater pictures ! Outstanding

Regarding the oil, there's probably a better choice but I don't know ... Gregg F was telling me that the larger Skymaster ones use such a system ... will have to check when I find the time.
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Old Jun 15, 2011, 01:43 AM
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3in1 is the same as sewing machine oil. Thin light viscosity.
Motorcycle fork oil is excellent stuff, the thinnest used to be 5 weight but they have 0 weight nowadays.
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Old Jun 16, 2011, 03:45 PM
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The motors have now been installed in the fans.

There's four solid screws at the front, secured with silicone, and four supports glued in with silicone at the back.

All the shaft adapter screws and nuts have been loctite'd.

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Old Jun 16, 2011, 03:46 PM
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I was also able to get a bit of work done on the motor/fan installation.

The fans fit perfectly in the nacelle opening, with no play. The front of the nacelle looks really solid, so that would be half of the motor mount.

The second half is a former that supports the fan assembly at the back. Then on the sides there will be two additional supports. Finally two ply braces will go from the rear former to the wing mount.

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Old Jun 16, 2011, 03:48 PM
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Here's btw a picture of the wing mounts for folks that did not get a set with the kit,

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Old Jun 16, 2011, 03:50 PM
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Amazon.de also delivered today a very nice book on the Me-262, with lots of color & bw pictures

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