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Posted by Ken59 | Mar 20, 2013 @ 04:00 PM | 2,740 Views
Ok, I was bored and waiting for the 2700kv motor to come in. So, I went ahead and pulled off the DDVP unit and replaced it with a Direct Drive 2000kv motor I had laying around. I did a rough wiring on it and put it on the test bench. At half throttle on the main, it almost kept up with the prop in the picture. At 8volt average, this motor is turning at 16000 rpm at no load. The 2700 will be at 21000 rpm! It might hold then. If not, Turnigy makes a little 3500kv motor, but it will have to come from China. This was with the gyro gain max out on the Turnigy 9x. It may come down to just the right prop to run. As you can see, I mounted the motor on the left side. This way, air is blowing into the motor for better cooling. The middle of this tail is pretty strong and should hold very well, especially since the motor with prop is under 20gram. What I really wanted to find out was the weight balance with the 2200mah battery. I put just a little bit of putty in the nose (approximately 3/4 inch diameter ball) and it is now nearly perfectly balanced. I am confident the weight bias problem is solved. Pictures are below!
Posted by Ken59 | Mar 12, 2013 @ 11:38 AM | 2,593 Views
Ok, here are the pictures of the mods. First let me say, I had parts laying around and was bored. Would I recommend people doing this, only if your bored and have the parts or money. Every since I bought the 9104, I have been trying to improve it and have learned quite a bit. Sure it cost me, but the knowledge I picked up is how they say "priceless". Would I buy another 9104, NO WAY. Would I buy anything with a brushed main and brushed tail in this type of heli? No. The folks who buy the MJX F45 are having the same issues with the main and tail motors burning out too quickly and thus they are modifying. The first mod they tend to do is the brushless main. Well, I just ditched the entire PCB and experimented with Honey Bee 3n1 with the brushed motor. It was more dependable, but did not solve the problem of bad motors. It is just hard to find a good brushed motor for these helis. Mine was shelved for a while, but I finally dusted it off and did the mods I wanted to try.

Below is a list of what I used and what I had to make.

Swashplate: 450 close plastic It is for a 5mm shaft so I found a solution. On the 9104 frame, where the lower frame attaches to the upper, are what appears to be spacers. These are just cosmetics, but they are a perfect 5mm outer to 4mm inner reducer for the 450 swashplate to made it work on the 9104 main shaft. I just put a little locktite on it when I inserted in the swash. I am not sure if it will hold and it may...Continue Reading
Posted by Ken59 | Jan 21, 2013 @ 09:09 AM | 2,339 Views
I have built a DDVP and will be testing shortly. It is a very good build and I will be posting vids and pics soon. With a 9ch TX/RX, I can mix it into a pot and run at a constant rate. Motor is a very strong 1700kv which I think, after running a few times, may be way to much for a 450, even at only half throttle. I have a 1500kv to run, also, with testing down to 1200kv to run at WOT. I built the unit with a metal HK tail holder and with a plastic also. I do prefer the metal and looking for the same tail holder at quantity discount. If you read this, let me know via this discussion, a PM, or an email. Thanks!