Help on GP Cap 20L-80"
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Help on GP Cap 20L-80"
I purchased a Cap 20L kit, great planes version with fiber fuse that came out sometime in the 80's. The kit calls for a one piece elevator joined through a ply connector plate. To avoid having to break the elevators apart if something went wrong or I needed to get to the throws for adjustment, I wanted to mount the servos on the fuse instead and make a 2 piece elevator, 1-servo per surface. I would also like to do the same for the rudder, (fuse mounted servos R and L). If I cut the holes out in the FUSE, 4 total, shoud I be concerned about comprising the integrity of the fuse, if so, what type of reinforcing is recommended??
This is my first larger plane and with gas power, It advises that once together, should weigh 15-18#'s, I was thinking about going with a DA-50. I flew 2 25% patty wags, one with the brisson 3.2 and one with the da-50, the da-50, not completely broken in yet TOTALLY stomped the Brisson, any opinions on the the DA-50 and reliability??
Also, I have a 6 channel JR. Cant really afford to jump up to the 8 yet. This kit will be running 7 servo's. With elevators having separate servos, am I configuring it with a Y harness and then running it into one channel on the reciever? Same with the Rudder? If so, am I looking at a reversing/trimming issue due to lack of tx ability as far as getting servos to run in the correct direction simultaneously?? IE) one servo needing to be reversed but the other not??
One last question. all my planes are currently glow, 60 size and under, the servos are just regular 517's and a couple 531's: Any suggestions on servo, reciever combo that would fit this application, preferrably JR???
Thanks in advance.
This is my first larger plane and with gas power, It advises that once together, should weigh 15-18#'s, I was thinking about going with a DA-50. I flew 2 25% patty wags, one with the brisson 3.2 and one with the da-50, the da-50, not completely broken in yet TOTALLY stomped the Brisson, any opinions on the the DA-50 and reliability??
Also, I have a 6 channel JR. Cant really afford to jump up to the 8 yet. This kit will be running 7 servo's. With elevators having separate servos, am I configuring it with a Y harness and then running it into one channel on the reciever? Same with the Rudder? If so, am I looking at a reversing/trimming issue due to lack of tx ability as far as getting servos to run in the correct direction simultaneously?? IE) one servo needing to be reversed but the other not??
One last question. all my planes are currently glow, 60 size and under, the servos are just regular 517's and a couple 531's: Any suggestions on servo, reciever combo that would fit this application, preferrably JR???
Thanks in advance.
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RE: Help on GP Cap 20L-80"
boogalloo:
Let see if I can help...
Question #1) Yes, this can be done and although I don't think you'll compromise the fuse, make sure the holes are staggered. Another thought is to reinforce the holes with a bit of fiberglass. And a even better solution, make your servo holes on the bottom of the elevator stabs like any other plane. Then for the rudder, use a pull-pull system. This way there's no holes to make in the fuse (except the holes where the pull-pull cable comes out, and they are small.) Follow that?
Question #2) This one's a no-brainer...Go with the DA50
Question #3) Use 'Y''s where you can, and if you put those rudder servos in the tail end of your fuse, since one will be on one side and the other on the other side, they will be back to back and won't have a direction issue as you can put the servo arm in the direction you need. One side will pull and the other side will push (and vs versa). Same with the elevator, if you mount the servos under the stab then there's no direction issue, just 'Y' them.
Question #4) If you don't want to go digital, but still have very good, strong servos try the JR 8101's. These should be plenty for a plane of this size (I think, 90oz torque.)
Here's a picture of where your servos should be placed if you stick to your design and don't use a pull-pull for the rudder (you'll see that there's only 2 servos in the fuse and they are for the push-pull rudder).
Let see if I can help...
Question #1) Yes, this can be done and although I don't think you'll compromise the fuse, make sure the holes are staggered. Another thought is to reinforce the holes with a bit of fiberglass. And a even better solution, make your servo holes on the bottom of the elevator stabs like any other plane. Then for the rudder, use a pull-pull system. This way there's no holes to make in the fuse (except the holes where the pull-pull cable comes out, and they are small.) Follow that?
Question #2) This one's a no-brainer...Go with the DA50
Question #3) Use 'Y''s where you can, and if you put those rudder servos in the tail end of your fuse, since one will be on one side and the other on the other side, they will be back to back and won't have a direction issue as you can put the servo arm in the direction you need. One side will pull and the other side will push (and vs versa). Same with the elevator, if you mount the servos under the stab then there's no direction issue, just 'Y' them.
Question #4) If you don't want to go digital, but still have very good, strong servos try the JR 8101's. These should be plenty for a plane of this size (I think, 90oz torque.)
Here's a picture of where your servos should be placed if you stick to your design and don't use a pull-pull for the rudder (you'll see that there's only 2 servos in the fuse and they are for the push-pull rudder).
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RE: Help on GP Cap 20L-80"
Quote, Question #3) Use 'Y''s where you can, and if you put those rudder servos in the tail end of your fuse, since one will be on one side and the other on the other side, they will be back to back and won't have a direction issue as you can put the servo arm in the direction you need. One side will pull and the other side will push (and vs versa). Same with the elevator, if you mount the servos under the stab then there's no direction issue, just 'Y' them. Unquote.
With the hookup shown in the picture I don't believe a simple Y would work as the elevators would move in opposite directions. In order to work, one pushrod would have to be moved to the opposite side of it's servo arm.
RJ
With the hookup shown in the picture I don't believe a simple Y would work as the elevators would move in opposite directions. In order to work, one pushrod would have to be moved to the opposite side of it's servo arm.
RJ
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RE: Help on GP Cap 20L-80"
RJConnet:
Caught me! Your correct. The picture was more or less to show him where to put the servos, rather than to put all 4 in the fuselage. In the picture I use a servo reverser, but like you said, 'In order to work, one pushrod would have to be moved to the opposite side of it's servo arm.'
Critical, but point well taken. If he followed the picture exactly it wouldn't work. Thanks for pointing that out.
Caught me! Your correct. The picture was more or less to show him where to put the servos, rather than to put all 4 in the fuselage. In the picture I use a servo reverser, but like you said, 'In order to work, one pushrod would have to be moved to the opposite side of it's servo arm.'
Critical, but point well taken. If he followed the picture exactly it wouldn't work. Thanks for pointing that out.
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RE: Help on GP Cap 20L-80"
Boogallo,
I also have a GP Fibreglass Cap20L NIB and plane to fly it. Here is what I have learned about it.
1. This plane has a history of flutter. If you go dual servos make them 100 oz each per wing.
2. The plans do call for a single elevator and they did this for a reason. Albiet its not a good one.
Notice the plans call for a Quadra 35 a boat anchor, this plane will build tail heavy per the plans.
if you install a DA-50 (to me thats like installing a Offenhauser in a VW bug) make sure you pay particular
attention to weight and balance. I am planing to split the elevators but have not decided on the motor set
up. I think starting at the fire wall and working my way back will allow me to install a good bar stock motor
and not have to worry about tail heavy. I plan to use internal dual servos and rods supported with rigid
foam inside for support worked on my Yellow AC cap 10b should work here too. Pull pull on the rudder
with digital all the way around.
3. Kitty Hawk Aviation has taken over the model and they no longer have Fiberglass fuses just canopies and
cowlings. Dont wreck what ever you do......you may not be able to get any parts.
4. The landing gear is weak. the wire too small the attachement too weak Beef it up. (more weight)
5. The wings can be glassed but if you want light cover them with ultra coat.
That's all I can think of, I copied a write up in MAN from years ago and have copies if you want. May be usefull I dont know.
Thats my story and I'm stick'n to it
jds
I also have a GP Fibreglass Cap20L NIB and plane to fly it. Here is what I have learned about it.
1. This plane has a history of flutter. If you go dual servos make them 100 oz each per wing.
2. The plans do call for a single elevator and they did this for a reason. Albiet its not a good one.
Notice the plans call for a Quadra 35 a boat anchor, this plane will build tail heavy per the plans.
if you install a DA-50 (to me thats like installing a Offenhauser in a VW bug) make sure you pay particular
attention to weight and balance. I am planing to split the elevators but have not decided on the motor set
up. I think starting at the fire wall and working my way back will allow me to install a good bar stock motor
and not have to worry about tail heavy. I plan to use internal dual servos and rods supported with rigid
foam inside for support worked on my Yellow AC cap 10b should work here too. Pull pull on the rudder
with digital all the way around.
3. Kitty Hawk Aviation has taken over the model and they no longer have Fiberglass fuses just canopies and
cowlings. Dont wreck what ever you do......you may not be able to get any parts.
4. The landing gear is weak. the wire too small the attachement too weak Beef it up. (more weight)
5. The wings can be glassed but if you want light cover them with ultra coat.
That's all I can think of, I copied a write up in MAN from years ago and have copies if you want. May be usefull I dont know.
Thats my story and I'm stick'n to it
jds