Pilot RC 35% (106") Extra 260

[ghoffman]

Use anything other than a 7950, whatever you pay for it will be a waste of that amount of money. It does not put out anywhere near the advertised torque, and it shakes worse than most of the people here that are just waking up now from last nights' festivities.

 

[gyro]

Use anything other than a 7950, whatever you pay for it will be a waste of that amount of money. It does not put out anywhere near the advertised torque, and it shakes worse than most of the people here that are just waking up now from last nights' festivities.

Uh oh... I just bought 2 HS-7950TH's for the Ailerons (they're setup for single servos)

 

[ghoffman]

Can you send them back?

 

[gyro]

Can you send them back?

Lol, no, I'm going to give them a shot.

 

[ghoffman]

Hitec claims 486 oz-in torque, but in this TBM test you can see they start out at 385 then go down fast from there to about 350 oz-in . My experience was similar in flight and it shook badly on the rudder. It resulted in rudder blowback on my 104 AJS, so I sent it back and Hitec said they did a firmware change. When it came back it still shook badly. So, at last year's WRAM show I went to the Hitec booth and asked a gentleman if he was Mike Mayberry. The guy said he was MM's boss. I told him about the lack of results of the change and he said oh well, it worked on the test bench. I gave it away for free after telling the guy the whole story. Even for free I did not want to screw a friend.
http://youtu.be/IqcGvJZkfp8

 

[gyro]

Hitec claims 486 oz-in torque, but in this TBM test you can see they start out at 385 then go down fast from there to about 350 oz-in . My experience was similar in flight and it shook badly on the rudder. It resulted in rudder blowback on my 104 AJS, so I sent it back and Hitec said they did a firmware change. When it came back it still shook badly. So, at last year's WRAM show I went to the Hitec booth and asked a gentleman if he was Mike Mayberry. The guy said he was MM's boss. I told him about the lack of results of the change and he said oh well, it worked on the test bench. I gave it away for free after telling the guy the whole story. Even for free I did not want to screw a friend.
http://youtu.be/IqcGvJZkfp8

While I can definitely see why you're not a fan, and had that happened to me, I wouldn't be either. Hopefully I don't have the same experience. Thanks for trying so save me the trouble you went through!

 

[ghoffman]

Well, I hope they have been improved by now and work well for you. If they don't, you can skip to the last step in this story (there was an intermediate chapter) and get Futaba BLS-157's!

 

[Drew]

Gary, you will need at least 450 on those wings running the single servo........

 

[gyro]

Gary, you will need at least 450 on those wings running the single servo........

7950s on 2s LiPo will work. I don't plan to go for 60 degrees deflection, so I'll gain some torque by using the inner holes on the arms. They're rated at 486 oz/in on 7.4v (power supply continuous voltage)

I just re-watched the TBM torque test linked above, and I have a couple of observations: They did it on a 1" arm, I plan to use 3/4". Their battery wasn't fully charged, only reading 8.3v. Also, their battery wasn't very good, dropping nearly .8 - 1v under a small 5a load.
I believe their test was more for demonstration purposes, rather than scientific benchmarking.

 

[nebwake]

I think you will still have blow back. I am running 2 7955's on my 122" pilot 260 and am getting some blowback at speed. I am probably switching them to something stronger.... But we'll see how much cash I have to spend this year on airplanes.