Hi Ixion. We met at Erias park and I think I had my Parat then. I've had her for 4 years now and when I'm home I use her every Sunday at Llanberis. I can't help with the Spectrum issue but may assist in other ways. I've added a pic on the bottom of this post showing how I've arranged the servos. First off Graupner make really nice kit but they missunderstood how a VS tug actually works. They specify a 60A ESC. This is way over the top. I run 2x12V7Ah batteries in parallel through a 20A switch and a 20A fuse driving one 25A Mtronics ESC driving both motors in parallel. I had to change over the wires on one motor so that the starboard unit turned clockwise (viewed from above) and the port unit turned anticlockwise. I run them both flat out at full speed (Graupner 150%). They get quite warm but if I spit on them they don't spit back. Never blown a fuse or had motor failure. Max current, units in water on max pitch, 6.5A. These motors are massively geared down. I haven't counted the teeth though so not sure of ratio.They work! Tug is not over powered, even when towing. The ESC isn't strictly needed. On the full size tug we don't adjust the revs, they are always full speed and the governer looks after the load. For delivery jobs we prefer to run on minimum RPM and maximum pitch (we are usually range critical and this way we get the greatest distance for our fuel load). We can't do this on Voiths unfortunately, the system won't let us. So on the model all that is required is an r/c switch or even an external manual switch. Fit an ESC by all means as you can have fun reducing the RPM to a minimum and learn a bit more slowly. They can seem a bit violent when you start off.
Next bit. Graupner specify 4 servos (2 for each unit). It CAN be done this way but makes handling much more complicated than it need be. The full size tug has only 3 controls viz. 2 levers, which alter ahead and astern pitch(and thus thrust)(these are the 2 servos on the center line which move the little lever athwartships at 90 degrees to the thrust), and a wheel which alters the athwartships pitch on BOTH units simultaneously. As the motors contra rotate if you move one little lever forward and the other aft both units will thrust in the same direction at 90 degrees to the centerline of the tug. The photo shows the athwartship servo in the port servo mounting opening. It is fitted with a 90 degree crank with one arm driving the port little lever and the other arm driving an idler rod across to a 90 degree idler crank in the starboard servo mounting position (You could substitute a stripped out servo with just the output shaft fitted). the other arm of the idler crank drives the starboard unit little lever in the opposite direction to the port one. (little lever is what I call the actuator pin in the center of the big wheel, but I can't remember what it's really called).
On the Tx I use ch 1 (right lever fore and aft) for stbd unit F & A thrust.
ch 3 (left lever F & A) for port unit F & A thrust.
I made 2 circular blanks from the Voith cutouts from the hull into gates for the Tx levers so the only move F & A. These gates have a notch in the center and a tightish fit on the lever arms so the levers stay central and need a little force to move F & A. I screwed these to the Tx case and they are removeable when using other models. Ch2 and 4 not used.
Now the tricky bit. I have a Graupner Tx. Ch 5 is controlled by a Pot mounted top right of Tx case. I use this channel for RPM. Ch6 is also controlled by a Pot also mounted top right next to Ch 5. I use Ch 6 to drive the athwartships servo. So Ch 6 is the wheel and used for steering. The advantage with this layout is that whichever direction you are going (forward or astern) if you turn the wheel to stbd (clockwise) the boat will turn to stbd. If you can't fit the extra pots then you can remove Ch 2 and 4 pots from the levers inside the Tx and mount them as I have said and just add knobs. If that doesn't suit you then leave the pots where they are and use Ch 2 for steering and Ch 4 for RPM. In my head that would be a bit complicated though!
As to how much throw on the little lever. Max range servo travel on my Tx is +150% to -150%. I find you don't need more than 50%. If you go too much they get noisy so I set the units to full speed (150%) and while running set the throw until max lever travel on Tx results in silence then back off 10% more. This is because when max lever and max steering are put on together they will get noisy again. Noise is strain!
A bit long winded but you can't really get simple with Voiths. PM me if you want a chat.
Hope it helps.
Jerry.
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Topic: Anyone set up Voiths with Spektrum DX6i (Read 6039 times)