Valac 250 Radal

**Ramjet** · 03-08-2019, 09:31 AM

finally found the location for the chassis built plate . just behind the pilots head . next will be to polish the wheel strut fairings , leaving them aluminum ..

**Ramjet** · 03-08-2019, 01:51 PM

finished up the landing gear covers

**Ramjet** · 03-18-2019, 04:54 PM

Hello Roger,
for easy and safe starting the engine, you need separate control of
the pump and the ignition. So you need two switches on the transmitter
anyway and two channels of course.

How to efficiently start the engine in short:

Switch off the ignition
Switch on the fuel pump
Close the choke (make sure it is FULLY closed)
Throttle at low idle
Flip the engine as if you wanted to start it until fuel begins to drip
out of the carburetor and then about 3 flips extra.
Open the choke
Switch on the ignition
Flip the engine, you will see it will 100% start running at the very
first flip, so you can concentrate on this 100%

To stop the engine:
switch off the ignition
switch off the fuel pump

When the engine has already been running before on the same day an
hour ago or so:
Close the choke
Throttle at low idle
Switch on the fuel pump
Flip the engine 2 or 3 times
Open the choke
switch on the ignition
flip the engine it will start the very first time

When the engine has been running a few minutes ago:
Choke is open
Throttle at low idle
switch on the fuel pump
switch on the ignition
flip the engine; it will start the very first flip

This starting technique may sound complicated and unusual, but the
priming is safe and very relaxed because the ignition is not on.
The other advantage is that the engine can also be primed 5 or 10
minutes before it actually needs to be started and then, when you fly
at a meeting your helper and the other people standing around you will
be surprised that the engine starts so effortless and on the very
first touch of the propeller EVERY TIME ...

Cheers,
Gerhard

**Ramjet** · 03-18-2019, 04:56 PM

On 2019-03-18 06:08, Toni Clark Shop wrote:
Hello Roger,
sorry for the bad quality of the manufacturers engine manual. We have
included it with your engine as our own English manual is not finished
and we thought you will not be able to read our German manual.

Here are the important points you must know:
The Valach ignition has the ignition switch integrated. One of the two
JR connectors is connected to a 2s LiPo battery, the other one is
connected directly to a receiver channel just like a servo. This
channel must be set in the transmitter to +50% and -50%. Do not leave
it at the standard setting of +-100%, as on some radios this can cause
malfunction of the ignition(switch). Which connector goes to the
receiver is easy to detect as only one will directly connect to the
receiver, the battery connector won't. Make sure not to mix this up
when you use extension leads.

The ignition does not (need to) detect the throttle setting, but it
knows the RPM and it knows the time (from the microprocessor clock).
If you start the engine at a throttle setting too high, the RPM will
rise rapidly and if the engine exceeds 3000 RPM in less than one
second after startup, the ignition will switch off the HT so that the
engine stops immediately. The ignition then will beep in a rapid
sequence for some seconds. After the beeping ends, you can restart the
engine - at a lower throttle setting.

Do not connect the fuel pump to the receiver battery! Connect it to
the ignition battery using a Y-cable, but make sure to cut the signal
wire in this Y-connector, only the plus and minus wire must remain.
The ignition will not work if the signal wire is not cut and is
connected to the signal wire on the battery connector on the ignition.

The fuel pump is connected to the battery and to a receiver channel.
The receiver channel switches the pump on and off and controls the
speed at which the pump is running. If you use a Jeti central box 200,
like I do, you must set the servo frame rate in the central box to a
fixed value, for example 17 ms, DO NOT LEAVE IT AT THE STANDARD "AUTO"
SETTING.
Nothing is connected to the IGN/PRG connector on the fuel pump, this
connector is not used.

Mount the pump very close to the fuel tank and below the fuel tank.
Please see attached picture of the fuel pump fuel lines.
On my Grumman I have set the fuel pump to a constant 50% power. It is
not recommended to control the fuel pump power according to the
throttle setting as for acceleration from idle the fuel flow will not
be sufficient.

NEVER run the pump dry for more than 3 seconds!

Sorry we actually missed to ship the pushrod tube, we will send it
today.

Best regards,
Gerhard

I should mention that when you turn the ignition on you will hear a series of ascending in tone beeps 5-6 followed by a a repeating beep every 2 seconds (to indicate ignition ON). when you turn the ignition off you will hear the same 5-6 beeps but descending in tone followed by a repeating beep every 4 seconds (to indicate ignition OFF) . pretty cool setup

**Ramjet** · 03-31-2019, 05:30 PM

Just finished the braces for transporting the wings , also made some fixtures so I can reduce the contact points of the flying wires from 14 to 4 points per side . takes about 5 min per side to assemble now . early in the build I changed the wing tube installation to make the wing tubes parallel so the wings could come off together . I will make some big square wing bags to transport them . Had 6" of snow yesterday so still have some time before it fly's.. .49.6 lbs and needed 3 oz tail weight to bring to factory CG .. hoping I have enough clearance with the 34" prop , Gerhard did tell me if I have clearance problems I could use a 32x18 3 blade but don't go any smaller .. This thing must have some monster torque ..

**Lowrider27** · 04-03-2019, 09:40 PM

Heh Roger. Just tuned into this thread. Man , you do beautiful work ! I love all the details you’ve incorporated into that bird.That motor in that plane is going to be a beautiful combination . Good work!