I think RANS should have followed the manufacturer guidelines on fastener size. However, since I also already have the #8 nutplates in place, I will drill the motor to that size and hope for the best. I expect there will be no issues as long as the screws aren’t over tightened.
I took the holes up in as small increments as possible. Looks ok, I’m just not a fan of that little real estate on the corners. I added a washer between the screw head and servo body.
@@s-21project92 I hear you, but given the direction of the forces, I am not too worried. You could completely break off the corners and the servo would still be constrained well in the shear direction so I see little concern. And using washers will distribute the clamping force well. I doubt these servos are capable of more than a few pounds of force so I suspect there is little concern.
Yeah that’s true. But still not a fan of the way they did that. Plus they spec a #20 hole for the 8-32 screw. I think that’s too tight and will also lead to cracking at the corners and should be a #19. It feels a lot better with that size.
@@s-21project92I am installing my servo today so am revisiting this. I agree that #20 is on the small side for a #8 screw, particularly if the holes in the nut plates aren’t precisely aligned with the holes in the servo body. Better to not put a lot of stress on the housing. I believe Ray Allen’s web site says that the housing is glass-filled plastic so it is much less likely to crack than is unreinforced plastic. Just for grins, I decided to call Ray Allen. The friendly man on the phone said they prefer to keep the screw size at #6, but he was very tactful and said he wouldn’t say that RANS was wrong to use #8. When I explained that I already had #8 nut plates installed and they would be very hard to replace, he said that he “would have no concern flying in an airplane with a trim servo attached with #8 screws.” 😁. So, I am not going to mess with the nutplates unless I have issues in the future with the servo case cracking. And even then, I won’t mess with the nutplates, but will instead fabricate a square metal ring that will go around the full perimeter of the actuator and then screw the ring to the nutplates. That will definitely hold, but would have the hassle of requiring a rebalance of the elevator. I really don’t foresee a problem though given the material used in the actuator body.
Just making note of this. If you knew beforehand, would you have installed #6 screw nut plates from the beginning? Maybe a recommendation to Ran’s to change that in the instructions.
Yeah, I would have done a 6-32 on all four from the beginning. The Ray Allen instructions don’t specifically say to NOT drill for an 8-32, but the way they say if needed to carefully size it up to a 6 implies to me that 6 is the largest they want you to go. Another weird thing in the text manual is it says to drill it #20 for the 8-32 screw. I think it needs to be a #19. The #20 hole makes it a really tight fit for the screw and seems like it would lead to a crack in the housing out to the corner.
@@s-21project92After reading this in the Ray Allen FAQ, I’m not too worried about strength of this material even with the larger holes. “We know of our actuators that are used successfully inside cowlings, but we are hesitant to recommend it. Although the DuPont Minlon® brand nylon we use is the same basic type that is used in BMW valve covers, the strength of the nylatron gears inside get weaker as temperatures climb above 180 degrees F. Try to keep the servo in a ventilated location under the cowl away from exhaust pipes or better yet, behind the firewall and use our B6 actuator.”
Looks good. Looking forward to the balance part.
Your videos are the bomb.
Thank you!
I installed and ran mine today off of a 12V ATV battery. I was surprised how loud that actuator is.
I think RANS should have followed the manufacturer guidelines on fastener size. However, since I also already have the #8 nutplates in place, I will drill the motor to that size and hope for the best. I expect there will be no issues as long as the screws aren’t over tightened.
I took the holes up in as small increments as possible. Looks ok, I’m just not a fan of that little real estate on the corners. I added a washer between the screw head and servo body.
@@s-21project92 I hear you, but given the direction of the forces, I am not too worried. You could completely break off the corners and the servo would still be constrained well in the shear direction so I see little concern. And using washers will distribute the clamping force well. I doubt these servos are capable of more than a few pounds of force so I suspect there is little concern.
Yeah that’s true. But still not a fan of the way they did that. Plus they spec a #20 hole for the 8-32 screw. I think that’s too tight and will also lead to cracking at the corners and should be a #19. It feels a lot better with that size.
@@s-21project92I am installing my servo today so am revisiting this. I agree that #20 is on the small side for a #8 screw, particularly if the holes in the nut plates aren’t precisely aligned with the holes in the servo body. Better to not put a lot of stress on the housing. I believe Ray Allen’s web site says that the housing is glass-filled plastic so it is much less likely to crack than is unreinforced plastic.
Just for grins, I decided to call Ray Allen. The friendly man on the phone said they prefer to keep the screw size at #6, but he was very tactful and said he wouldn’t say that RANS was wrong to use #8. When I explained that I already had #8 nut plates installed and they would be very hard to replace, he said that he “would have no concern flying in an airplane with a trim servo attached with #8 screws.” 😁. So, I am not going to mess with the nutplates unless I have issues in the future with the servo case cracking. And even then, I won’t mess with the nutplates, but will instead fabricate a square metal ring that will go around the full perimeter of the actuator and then screw the ring to the nutplates. That will definitely hold, but would have the hassle of requiring a rebalance of the elevator. I really don’t foresee a problem though given the material used in the actuator body.
Good info. Thanks!
Just making note of this. If you knew beforehand, would you have installed #6 screw nut plates from the beginning? Maybe a recommendation to Ran’s to change that in the instructions.
Yeah, I would have done a 6-32 on all four from the beginning. The Ray Allen instructions don’t specifically say to NOT drill for an 8-32, but the way they say if needed to carefully size it up to a 6 implies to me that 6 is the largest they want you to go. Another weird thing in the text manual is it says to drill it #20 for the 8-32 screw. I think it needs to be a #19. The #20 hole makes it a really tight fit for the screw and seems like it would lead to a crack in the housing out to the corner.
@@s-21project92After reading this in the Ray Allen FAQ, I’m not too worried about strength of this material even with the larger holes. “We know of our actuators that are used successfully inside cowlings, but we are hesitant to recommend it. Although the DuPont Minlon® brand nylon we use is the same basic type that is used in BMW valve covers, the strength of the nylatron gears inside get weaker as temperatures climb above 180 degrees F. Try to keep the servo in a ventilated location under the cowl away from exhaust pipes or better yet, behind the firewall and use our B6 actuator.”