500 My Trex500 just showed up in the mail.
- Thread starter zenmetsu
- Start date
zenmetsu
Member
I found that to be best . . . also for cooling
That was my thought as well. I will likely flip mine around so that the motor leads come out the front and the battery leads out the rear.
There is not much noise/RF coming from the battery leads, but the motor leads are a different story all together. I would like to keep them as far from my receiver as possible, just in case.
On another note, my Castle Phoenix 100 had a manufacturing defect. They have a plastic casing around the unit, and they pinched the 3-wire cable for the throttle connection (going to receiver) between the plastic and one of the filtering capacitors. The wire was pressed very thin and although no copper was showing, I felt that the wire had been compromised and some of the conductors were probably broken. I snipped an inch off of the cable and re-soldered it.
While I was in there, I noticed that there are pads for a second 3-wire connector. Maybe I will experiment in the future.
zenmetsu
Member
CoG is important, but the most important thing is that the helicopter is dynamically stable. Static stability is not a big deal. Most helicopters are not statically balanced; the tail rotor is on one side for instance.
Even while in flight, dynamic forces are such that there is an imbalance that requires correction. Most of the time this involves adding cyclic to offset the thrust of the tail, so the ESC really should be mounted on the tail side if anything so that gravity will cant the helicopter. From an energy standpoint, this is much more efficient than adding cyclic and introducing aerodynamic drag.
This is why many helicopters are built with an off-center main shaft. A classic example being my favorite whirlybird, the Mi-24 Hind. With the tail being on the left, the main rotor is offset to the right of the fuselage centerline and thus CoG so that the helicopter will naturally tilt to the left and counteract the thrust of the tail without having to waste energy on cyclic deflection.
Even while in flight, dynamic forces are such that there is an imbalance that requires correction. Most of the time this involves adding cyclic to offset the thrust of the tail, so the ESC really should be mounted on the tail side if anything so that gravity will cant the helicopter. From an energy standpoint, this is much more efficient than adding cyclic and introducing aerodynamic drag.
This is why many helicopters are built with an off-center main shaft. A classic example being my favorite whirlybird, the Mi-24 Hind. With the tail being on the left, the main rotor is offset to the right of the fuselage centerline and thus CoG so that the helicopter will naturally tilt to the left and counteract the thrust of the tail without having to waste energy on cyclic deflection.
zenmetsu
Member
Man, I just cannot catch a break.
My CC ESC had a minor defect: fixable by snipping a wire and re-soldering. No problem.
My T-Rex 500 however, I have noticed a defect in the swash plate. There is a lot of bearing play and the upper/lower halves of the swash have almost 1mm of play. Looks like from the reports that this is the norm nowadays and that going to a 3rd party swash with dual races is the only way to get around it. >.<
I wish that there was a way to tighten up the bearing in the swash.
My CC ESC had a minor defect: fixable by snipping a wire and re-soldering. No problem.
My T-Rex 500 however, I have noticed a defect in the swash plate. There is a lot of bearing play and the upper/lower halves of the swash have almost 1mm of play. Looks like from the reports that this is the norm nowadays and that going to a 3rd party swash with dual races is the only way to get around it. >.<
I wish that there was a way to tighten up the bearing in the swash.
heli-maniac
New Member
just go to the DFC set up and flybarless and you will not have to worry about that
zenmetsu
Member
Except that I've read that the DFC heads are flawed at the moment and anything bigger than a 450 is playing with fire. They implemented a workaround by using super hard dampers, but you might as well just machine the rotor hub with a smaller hole to eliminate the need for the dampers all together.
I think I'll just fly this swash plate until it poops itself and then decide if I want to go to DFC or not. Maybe they will come up with a new head design by then.
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Whirlybird
Member
Nice thoughts on the CoG 
Another point is that the ESC is not that heavy and very close the the helicopter's centerline to have any significant effect on left/right static balance . . . much would go the same with having a muffler on oneside of a nitro
Another point is that the ESC is not that heavy and very close the the helicopter's centerline to have any significant effect on left/right static balance . . . much would go the same with having a muffler on oneside of a nitro
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Tony
Staff member
another thing is, CoG is not "as" important on a helicopter as it is on a plane. A helicopter can easily trim out slight differences in weight pretty easily. However as I'm sure you know, this puts unneeded stress on parts of the helicopter and can wear out parts a little faster.
zenmetsu
Member
Yeah, I am thinking that the amount of CoG offset is negligible.
I just made a rather comical discovery. I mounted my receiver on the upper tray, far from the ESC, figuring that my gyro could go in the lower one. The GY401 that I have from my 250's early days is too tall to fit on top of the lower tray because it will hit the tail servo. I cannot mount it on the underside of the lower tray because of the aluminum support bracket that the lower frame attaches to. Funny that my tiny 250 was more accommodating of large gyros than this beast.
I'll grab some pics to show where I have stuff mounted. The anticipation of flying this thing is killing me.
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As far as the canopy is concerned, I have painted a few layers, but now I am getting to some of the tricky stuff and I am going to be experimenting since I do not yet have an airbrush. More on this in a sec.
I am finding myself needing to cut small circles in a masking film or masking tape, and find that it gets somewhat hard to make a perfect circle with an X-acto or a pair of fine scissors. Maybe I am just not the artistic type.
I am going to try a really crazy approach. Since this layer is black, I am going to attempt laserjet toner transfer and see if I can get the toner (plastic) to stick to the paint when heated. If so, then I can simply print all sorts of intricate designs and have a simple method to getting them onto my canopy. I'll post the results shortly.
I just made a rather comical discovery. I mounted my receiver on the upper tray, far from the ESC, figuring that my gyro could go in the lower one. The GY401 that I have from my 250's early days is too tall to fit on top of the lower tray because it will hit the tail servo. I cannot mount it on the underside of the lower tray because of the aluminum support bracket that the lower frame attaches to. Funny that my tiny 250 was more accommodating of large gyros than this beast.
I'll grab some pics to show where I have stuff mounted. The anticipation of flying this thing is killing me.
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As far as the canopy is concerned, I have painted a few layers, but now I am getting to some of the tricky stuff and I am going to be experimenting since I do not yet have an airbrush. More on this in a sec.
I am finding myself needing to cut small circles in a masking film or masking tape, and find that it gets somewhat hard to make a perfect circle with an X-acto or a pair of fine scissors. Maybe I am just not the artistic type.
I am going to try a really crazy approach. Since this layer is black, I am going to attempt laserjet toner transfer and see if I can get the toner (plastic) to stick to the paint when heated. If so, then I can simply print all sorts of intricate designs and have a simple method to getting them onto my canopy. I'll post the results shortly.
callsign4223
Staff member
Geek points +1000
callsign4223
Staff member
+5000 for making your own pcb.
I am starting to feel behind the curve, I need to go do something geeky like setup a VMware server or something.
I am starting to feel behind the curve, I need to go do something geeky like setup a VMware server or something.
zenmetsu
Member
Don't talk to me about vmWare, lol. That's practically all I do at work. >.<
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BTW, this trick is working well. I try to get as much of the paper fiber off of the toner after the transfer, but it still dries and the fiber is white. When I hit the area with clear coat, however, the paper fibers go transparent again.
This may be a much better method than I first thought. Surprised that no one else has been doing this.
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The rough, decayed look is what I was hoping for, so I am rubbing the toner a bit to flake some off. I am really excited now.
Luckily I have access to a color laser printer... this might get good, fast.
- - - Updated - - -
BTW, this trick is working well. I try to get as much of the paper fiber off of the toner after the transfer, but it still dries and the fiber is white. When I hit the area with clear coat, however, the paper fibers go transparent again.
This may be a much better method than I first thought. Surprised that no one else has been doing this.
- - - Updated - - -
The rough, decayed look is what I was hoping for, so I am rubbing the toner a bit to flake some off. I am really excited now.
Luckily I have access to a color laser printer... this might get good, fast.
