D4 Servo Woes

dibble34 · #1 07-06-2009

Hi all

Having a few problems with my d4 destroying servos and wondered if anyone has had similar problems or could offer any advice.

I have gone through 2 (cheap acoms) servos in 3 weeks

. The first one failed quickly as i discovered the servo saver was solid. I took this apart and greased it all up and made sure it had give in it. Things seem much better but again today it killed another servo. Is there a trick to these servo savers and knowing how tight they should be?

I figure my other option is to get a metal geared servo. Any advice gratefully received

Cheers

Dave

Si Coe · #2 07-06-2009

You don't need a metal geared servo, you just need a decent servo. The cheap Acoms ones aren't very good at all.
I'm not running metal gears in my D4 - I've got a plastic geared KO. Its a high end servo, just not metal. Before the D4 it lived in my Cat'98. I removed it from the Cat for the D4 and replaced it with an Acoms AS7 I had lying around. It lasted less than 4 mins. The Ko has been in there for years !

dibble34 · #3 07-06-2009

Thanks, i figured the acoms might not be high enough spec for the D4. I can't get a KO as out of my price range, but i'll look into getting something a bit better. I think Hitec do some tougher servo's. Car has such good steering i just went for a cheap servo, didn't occur to me about it not being tough enough.

mikeyscott · #4 07-06-2009

I mate, KO servos rock. However I killed mine today after finding the servo saver glued up in my B4..

I'd look at KO, Savox or Sanwa. Going to run a Savox in my B4 when I get it back and KO the Losi (fingers crossed my 1001 fet.)

dibble34 · #5 07-06-2009

Quote:

Originally Posted by mikeyscott

I mate, KO servos rock. However I killed mine today after finding the servo saver glued up in my B4..

I'd look at KO, Savox or Sanwa. Going to run a Savox in my B4 when I get it back and KO the Losi (fingers crossed my 1001 fet.)

Ouch mate sounds expensive. Just purchased a 2nd hand hitec for £7 posted from the bay, looks quite good so fingers crossed.

Gonna also make sure the wheels don't turn too far as i guess that won't help!

dibble34 · #6 09-06-2009

Hi All

I now have a replacement servo, looking at the D4 Manual I have to make sure the steering arm is pointing straight up when fitting to the servo. Looking at the manual it should then be able to move 90 degrees right and left. Is this right? Seems like a lot of travel to me?

Any advise gratefully received, desperate not to destroy servo number 3

Cheers

Dave

jim76 · #7 09-06-2009

the servo won't need to move the full 90 degrees. Do you have any end point adjustments on your transmitter so that you can adjust the servo to stop when the car is at full lock?
If not then you may have to play with different length servo horns to stop the servo pushing when the wheel is at full lock as this is what can do a lot of damage.

dibble34 · #8 09-06-2009

Quote:

Originally Posted by jim76

the servo won't need to move the full 90 degrees. Do you have any end point adjustments on your transmitter so that you can adjust the servo to stop when the car is at full lock?
If not then you may have to play with different length servo horns to stop the servo pushing when the wheel is at full lock as this is what can do a lot of damage.

Hi James

Yes i can adjust the end points, what sort of angle should i look for at full lock. One of my suspisions is that the lock is too far and this is putting too much pressure on the servo if i hit something

mikeyscott · #9 09-06-2009

I've reduce the range of my servo on my helios & EX-5 so that it doesn't travel too far etc.

jim76 · #10 09-06-2009

just fit your desired servo horn, then adjust the end points so that the servo stops when the wheels acheive full lock in each direction. i usually set mine to continue a fraction more after they first reach full lock so that it can hold the wheels in full lock under hard cornering.

dibble34 · #11 09-06-2009

thanks, will give it a go

telboy · #12 09-06-2009

Yeah keep an eye out on fleabay for some good bargains, also on the for sale section on here. I just bought a KO servo off mr Skelding for £30.
I also bought a couple of Futaba low profile High speed metal geared ones of Ebay for about £30 each, and they've done 2 years worth of racing in the D4/Cat/Cyber.

When you think about what you've spent on the Acoms servos, you could have bought a decent one by now.

So worth keeping an eye out.

I used to buy cheap servos, but only buy good ones now. Its worth it in the long run.

jim76 · #13 09-06-2009

very true. both of my KO 2123s are from here or ebay for around £30. lasted me the last 3 years and still going strong. I also have an 18 year old KO1003 in my micro!! they go for ever, great investments