Forward drift need help

mvert · 08-19-2012, 10:53 PM

Stumped on this one. New Ar7200bx installed on Align 600 efl. Beast is fine on the ground no drifting. As soon as I get it into the air It starts a forward drift getting worse the longer it is in the air. After I set it down you can watch the swash drift forward After all I have read it sounds like a vibration issue or a radio imput issue. I have another 600 efl with a vbar on it. The vibe chart reads very low on it. So I have been swapping out parts trying to find the problem. By this method I"m pretty positive I have got the vibes to a acceptable level. I have used up to 3 layers of 3m tape. swapped out the motors. swapped out the hole tail boom, with no change. I have increased the deadband all the way up. No change. dx7s radio. I don't have any wires transferring vibes to the unit. I checked and replaced all the bearings. I have checked for trim and subtrim 15 times. What am I missing?

Hendo67 · 08-20-2012, 01:09 AM

Check the main shaft and spindle. Easy way to check the main without removing is to:
1. Cradle the heli horizontally in your arms- head away from you.
2. Grasp the swash in the front and back and apply some side load against the main shaft.
3. Have an assistant spin the head while you feel for movement in the swash. If you have any oscillation at all- replace the main.

Also set all your trim steps to zero. That way you can't accidentally add some trim.

mvert · 08-20-2012, 07:47 AM

I have replaced main shaft and checked spindled. I'll just swap heads to double check. I can't find trim step on a dx7s My dx8 has it and I have turnned the trim step to 0> But I don't think a 7 has that feature.

ahahn · 08-20-2012, 03:22 PM

Quote:

Originally Posted by mvert

I have replaced main shaft and checked spindled. I'll just swap heads to double check. I can't find trim step on a dx7s My dx8 has it and I have turnned the trim step to 0> But I don't think a 7 has that feature.

Well just make sure you have no trim or subtrim in the transmitter for the cyclic and rudder channels.

Whenever you have a drift (I assume the heli is actually rotating forward), it usually means there is some type of vibration getting into the gyro sensors and confusing them, or the BeastX thinks it is being told to move that direction. This latter can be trim, or in rare cases, the transmitter is out of specs or is drifting.

Most likely is vibration, IMHO.

mvert · 08-20-2012, 10:28 PM

I agree everything tells me it is vibs. However i have a vbar on a other heli sitting side by side the vbar chart tells me my vibes are low. I put my hand on the beast and I have less vibes than the vbar heli. Plus I have had 3 other helis with a beast set up and I swear they had more vibes and no problems. Anyway tomorrow I should have time to change out parts untill I find the problem. I will report back.

ronlund · 08-21-2012, 08:40 AM

Just curious. Have you tried adjusting Parameter A?

mvert · 08-24-2012, 08:17 AM

Yes I did adjust "a" That has worked on my other ships in the past. However this is a Active forward moving swash. Like it is getting a command to move forward. I had time to put another brand new beast on it last night. So I should find out if it was a bad set up or a bad beast tomorrow. P.S Great Store you have. Thanks for keeping so much in stock

ronlund · 08-24-2012, 04:54 PM

Okay. I'm anxious to know the results. If the new one does the same thing, it's more than likely a transmitter issue. Would you agree? Or, do you have other models on that transmitter with a Beast?

mvert · 08-24-2012, 09:16 PM

No I don't have any other models on that radio. I maxed out the deadband on the beast with no change at all. I don't have any trim or subtrim . I'm thinking that rules out the radio but maybe not. I just got the set up done on the new beast. Too dark up here for a test flight. Will let you know tomorrow .

mvert · 08-25-2012, 02:51 PM

Problem Solved! We flew the new beast and no drift what so ever. We made no other changes. Same two layers of 3m mounting tape. All the same parts on the original 600 that would make the first beast drift. And all the same radio settings. I hope Horizon will replace the first Beast.

08-19-2012, 10:53 PM	#1
mvert Registered Users My HF Map location Join Date: Jun 2009 Location: Montana	Forward drift need help Stumped on this one. New Ar7200bx installed on Align 600 efl. Beast is fine on the ground no drifting. As soon as I get it into the air It starts a forward drift getting worse the longer it is in the air. After I set it down you can watch the swash drift forward After all I have read it sounds like a vibration issue or a radio imput issue. I have another 600 efl with a vbar on it. The vibe chart reads very low on it. So I have been swapping out parts trying to find the problem. By this method I"m pretty positive I have got the vibes to a acceptable level. I have used up to 3 layers of 3m tape. swapped out the motors. swapped out the hole tail boom, with no change. I have increased the deadband all the way up. No change. dx7s radio. I don't have any wires transferring vibes to the unit. I checked and replaced all the bearings. I have checked for trim and subtrim 15 times. What am I missing?

08-20-2012, 01:09 AM	#2
Hendo67 Registered Users Join Date: Jun 2008 Location: Minneapolis, MN	Check the main shaft and spindle. Easy way to check the main without removing is to: 1. Cradle the heli horizontally in your arms- head away from you. 2. Grasp the swash in the front and back and apply some side load against the main shaft. 3. Have an assistant spin the head while you feel for movement in the swash. If you have any oscillation at all- replace the main. Also set all your trim steps to zero. That way you can't accidentally add some trim. __________________ Synergy N5c : Synergy E7 : T700

08-21-2012, 08:40 AM	#6
ronlund Registered Users Join Date: Apr 2004 Location: Corpus Christi, TX	Just curious. Have you tried adjusting Parameter A? __________________ To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. 800-321-9909

08-24-2012, 04:54 PM	#8
ronlund Registered Users Join Date: Apr 2004 Location: Corpus Christi, TX	Okay. I'm anxious to know the results. If the new one does the same thing, it's more than likely a transmitter issue. Would you agree? Or, do you have other models on that transmitter with a Beast? __________________ To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. 800-321-9909

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

08-20-2012, 07:47 AM	#3
mvert Registered Users Thread Starter My HF Map location Join Date: Jun 2009 Location: Montana	I have replaced main shaft and checked spindled. I'll just swap heads to double check. I can't find trim step on a dx7s My dx8 has it and I have turnned the trim step to 0> But I don't think a 7 has that feature.

08-20-2012, 10:28 PM	#5
mvert Registered Users Thread Starter My HF Map location Join Date: Jun 2009 Location: Montana	I agree everything tells me it is vibs. However i have a vbar on a other heli sitting side by side the vbar chart tells me my vibes are low. I put my hand on the beast and I have less vibes than the vbar heli. Plus I have had 3 other helis with a beast set up and I swear they had more vibes and no problems. Anyway tomorrow I should have time to change out parts untill I find the problem. I will report back.

08-24-2012, 08:17 AM	#7
mvert Registered Users Thread Starter My HF Map location Join Date: Jun 2009 Location: Montana	Yes I did adjust "a" That has worked on my other ships in the past. However this is a Active forward moving swash. Like it is getting a command to move forward. I had time to put another brand new beast on it last night. So I should find out if it was a bad set up or a bad beast tomorrow. P.S Great Store you have. Thanks for keeping so much in stock

08-24-2012, 09:16 PM	#9
mvert Registered Users Thread Starter My HF Map location Join Date: Jun 2009 Location: Montana	No I don't have any other models on that radio. I maxed out the deadband on the beast with no change at all. I don't have any trim or subtrim . I'm thinking that rules out the radio but maybe not. I just got the set up done on the new beast. Too dark up here for a test flight. Will let you know tomorrow .

08-25-2012, 02:51 PM	#10
mvert Registered Users Thread Starter My HF Map location Join Date: Jun 2009 Location: Montana	Problem Solved! We flew the new beast and no drift what so ever. We made no other changes. Same two layers of 3m mounting tape. All the same parts on the original 600 that would make the first beast drift. And all the same radio settings. I hope Horizon will replace the first Beast.