'Happy New Year Everyone!
Jim and I have decided to build new wings for our UC-61. Makes sense to us, as almost everything else has been rebuilt. We're looking for wing jigs so if anyone knows where we can borrow, build or buy, give Jim or me a shout via the internet. Work is progressing albeit slowly. Finding someone with a rolling swedge was a trick. Come to find out one of our local hangers has one. Great news for us, as the trim tab cables are one of the last pieces to go in place before pre-cover inspection. Cheers.
Bob Coon
Jim Chybicki
HB-690 UC-61K
[Non-text portions of this message have been removed]'
Re: Wing Jig for 24's
-
robert Etter
- Posts: 234
- Joined: Tue Feb 27, 2001 7:37 pm
Re: Wing Jig for 24's
'A wing jig would be nice, provided that one exists, but it is not necessary.
I am sure that there may be someone out there that could correct me where I am wrong.
The primary concern would be to ensure that the wing attach fittings (Wing root) are as close to perfectly aligned with one another, front to rear, and the first bay is square, and all subsequent wing bays are square to one another, and the spars are straight.
I used a metal rod installed through both the front wing attach fitting on the fuselage and the rear fitting to verify the alignment of the fittings to one another. What I found was that both fittings were within a couple thousandth of an inch. Considering the airplane had been nearly destroyed once before, I thought that variance to be very good. Then moved that over to the wing with the same rods, to verify the alignment of the wing. The spar spacing shouldn't be a problem considering the way that everything is put together. I checked it for my own peace of mind. It was fine. When I finished the wings and put them on the airframe, the actually fit, and I was pleasently surprised to find only 3/4" variance between the center aileron hinge point and the rudder post.
Be sure when you drill the holes in the spars for the bushings and through bolts, use the longest drill possible. Around 6-8 inches in length would be good. I layer the old spar over the new one, clamped them together and kept them flat end to end. Then using the old spar as a template, I drilled one hole at the butt end that would later be used for a bushing and another at the other end that would be used for a through bolt for the last compression strut. Then I pinned the two spars together. All the while keeping both spars perfectly flat, end to end. If the assembly is bowed when the holes are drilled, you may not be happy with the results. Your may then need to make bushings that have holes that are slightly off center, or you will need to plug the holes and re-drill them. Use extreme care when drilling the holes for the bushings at the butt end of the spars. A few thousandths off on one could magnify into a bigger problem for the other holes.
I think that you will be lucky in one respect. I think that the bushings that were used in the Military wings were all anodized, i.e. very little corrosion. I have most of a set (1 wing) of the original anodized bushing (used).
Most everything else that you will come up against will be straight forward. I did find that with putting the plywood on the leading edge, putting the skin on across 3 bays at a time worked really well for me. I was working alone. The only area of the skin that need to be pre-bent was that at the very nose of the wing. About 4 inches. I first beveled the end the material that would overlay an adjacent section, marked the skin where the bend needed to be. I took two lengths of paper towels, longer than the skin section that I was working with, folded length wise twice and wetted them. Layer one on the front side and the other on the back side of the skin. After an hour or so, I clamped them the wing and let them dry. After drying, you can guess the rest. You can look at it for yourself, I let the glue set up before I glued and nailed the skin to the top and bottom of the spar.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]'
I am sure that there may be someone out there that could correct me where I am wrong.
The primary concern would be to ensure that the wing attach fittings (Wing root) are as close to perfectly aligned with one another, front to rear, and the first bay is square, and all subsequent wing bays are square to one another, and the spars are straight.
I used a metal rod installed through both the front wing attach fitting on the fuselage and the rear fitting to verify the alignment of the fittings to one another. What I found was that both fittings were within a couple thousandth of an inch. Considering the airplane had been nearly destroyed once before, I thought that variance to be very good. Then moved that over to the wing with the same rods, to verify the alignment of the wing. The spar spacing shouldn't be a problem considering the way that everything is put together. I checked it for my own peace of mind. It was fine. When I finished the wings and put them on the airframe, the actually fit, and I was pleasently surprised to find only 3/4" variance between the center aileron hinge point and the rudder post.
Be sure when you drill the holes in the spars for the bushings and through bolts, use the longest drill possible. Around 6-8 inches in length would be good. I layer the old spar over the new one, clamped them together and kept them flat end to end. Then using the old spar as a template, I drilled one hole at the butt end that would later be used for a bushing and another at the other end that would be used for a through bolt for the last compression strut. Then I pinned the two spars together. All the while keeping both spars perfectly flat, end to end. If the assembly is bowed when the holes are drilled, you may not be happy with the results. Your may then need to make bushings that have holes that are slightly off center, or you will need to plug the holes and re-drill them. Use extreme care when drilling the holes for the bushings at the butt end of the spars. A few thousandths off on one could magnify into a bigger problem for the other holes.
I think that you will be lucky in one respect. I think that the bushings that were used in the Military wings were all anodized, i.e. very little corrosion. I have most of a set (1 wing) of the original anodized bushing (used).
Most everything else that you will come up against will be straight forward. I did find that with putting the plywood on the leading edge, putting the skin on across 3 bays at a time worked really well for me. I was working alone. The only area of the skin that need to be pre-bent was that at the very nose of the wing. About 4 inches. I first beveled the end the material that would overlay an adjacent section, marked the skin where the bend needed to be. I took two lengths of paper towels, longer than the skin section that I was working with, folded length wise twice and wetted them. Layer one on the front side and the other on the back side of the skin. After an hour or so, I clamped them the wing and let them dry. After drying, you can guess the rest. You can look at it for yourself, I let the glue set up before I glued and nailed the skin to the top and bottom of the spar.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]'
-
ROBERT COON
- Posts: 26
- Joined: Sun Aug 24, 2003 11:39 am
Re: Wing Jig for 24's
'Bob,
Thanks for the great information. Sure is a good feeling to know their are folks out there who are going through or have gone through some of the same experiences we are. Your suggestions are great and we'll use them. No doubt, we'll be back for additional information and input as we progress. Thanks again. Bob
Robert Etter wrote:
A wing jig would be nice, provided that one exists, but it is not necessary.
I am sure that there may be someone out there that could correct me where I am wrong.
The primary concern would be to ensure that the wing attach fittings (Wing root) are as close to perfectly aligned with one another, front to rear, and the first bay is square, and all subsequent wing bays are square to one another, and the spars are straight.
I used a metal rod installed through both the front wing attach fitting on the fuselage and the rear fitting to verify the alignment of the fittings to one another. What I found was that both fittings were within a couple thousandth of an inch. Considering the airplane had been nearly destroyed once before, I thought that variance to be very good. Then moved that over to the wing with the same rods, to verify the alignment of the wing. The spar spacing shouldn't be a problem considering the way that everything is put together. I checked it for my own peace of mind. It was fine. When I finished the wings and put them on the airframe, the actually fit, and I was pleasently surprised to find only 3/4" variance between the center aileron hinge point and the rudder post.
Be sure when you drill the holes in the spars for the bushings and through bolts, use the longest drill possible. Around 6-8 inches in length would be good. I layer the old spar over the new one, clamped them together and kept them flat end to end. Then using the old spar as a template, I drilled one hole at the butt end that would later be used for a bushing and another at the other end that would be used for a through bolt for the last compression strut. Then I pinned the two spars together. All the while keeping both spars perfectly flat, end to end. If the assembly is bowed when the holes are drilled, you may not be happy with the results. Your may then need to make bushings that have holes that are slightly off center, or you will need to plug the holes and re-drill them. Use extreme care when drilling the holes for the bushings at the butt end of the spars. A few thousandths off on one could magnify into a bigger problem for the other holes.
I think that you will be lucky in one respect. I think that the bushings that were used in the Military wings were all anodized, i.e. very little corrosion. I have most of a set (1 wing) of the original anodized bushing (used).
Most everything else that you will come up against will be straight forward. I did find that with putting the plywood on the leading edge, putting the skin on across 3 bays at a time worked really well for me. I was working alone. The only area of the skin that need to be pre-bent was that at the very nose of the wing. About 4 inches. I first beveled the end the material that would overlay an adjacent section, marked the skin where the bend needed to be. I took two lengths of paper towels, longer than the skin section that I was working with, folded length wise twice and wetted them. Layer one on the front side and the other on the back side of the skin. After an hour or so, I clamped them the wing and let them dry. After drying, you can guess the rest. You can look at it for yourself, I let the glue set up before I glued and nailed the skin to the top and bottom of the spar.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]'
Thanks for the great information. Sure is a good feeling to know their are folks out there who are going through or have gone through some of the same experiences we are. Your suggestions are great and we'll use them. No doubt, we'll be back for additional information and input as we progress. Thanks again. Bob
Robert Etter wrote:
A wing jig would be nice, provided that one exists, but it is not necessary.
I am sure that there may be someone out there that could correct me where I am wrong.
The primary concern would be to ensure that the wing attach fittings (Wing root) are as close to perfectly aligned with one another, front to rear, and the first bay is square, and all subsequent wing bays are square to one another, and the spars are straight.
I used a metal rod installed through both the front wing attach fitting on the fuselage and the rear fitting to verify the alignment of the fittings to one another. What I found was that both fittings were within a couple thousandth of an inch. Considering the airplane had been nearly destroyed once before, I thought that variance to be very good. Then moved that over to the wing with the same rods, to verify the alignment of the wing. The spar spacing shouldn't be a problem considering the way that everything is put together. I checked it for my own peace of mind. It was fine. When I finished the wings and put them on the airframe, the actually fit, and I was pleasently surprised to find only 3/4" variance between the center aileron hinge point and the rudder post.
Be sure when you drill the holes in the spars for the bushings and through bolts, use the longest drill possible. Around 6-8 inches in length would be good. I layer the old spar over the new one, clamped them together and kept them flat end to end. Then using the old spar as a template, I drilled one hole at the butt end that would later be used for a bushing and another at the other end that would be used for a through bolt for the last compression strut. Then I pinned the two spars together. All the while keeping both spars perfectly flat, end to end. If the assembly is bowed when the holes are drilled, you may not be happy with the results. Your may then need to make bushings that have holes that are slightly off center, or you will need to plug the holes and re-drill them. Use extreme care when drilling the holes for the bushings at the butt end of the spars. A few thousandths off on one could magnify into a bigger problem for the other holes.
I think that you will be lucky in one respect. I think that the bushings that were used in the Military wings were all anodized, i.e. very little corrosion. I have most of a set (1 wing) of the original anodized bushing (used).
Most everything else that you will come up against will be straight forward. I did find that with putting the plywood on the leading edge, putting the skin on across 3 bays at a time worked really well for me. I was working alone. The only area of the skin that need to be pre-bent was that at the very nose of the wing. About 4 inches. I first beveled the end the material that would overlay an adjacent section, marked the skin where the bend needed to be. I took two lengths of paper towels, longer than the skin section that I was working with, folded length wise twice and wetted them. Layer one on the front side and the other on the back side of the skin. After an hour or so, I clamped them the wing and let them dry. After drying, you can guess the rest. You can look at it for yourself, I let the glue set up before I glued and nailed the skin to the top and bottom of the spar.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]
[Non-text portions of this message have been removed]'
-
robert Etter
- Posts: 234
- Joined: Tue Feb 27, 2001 7:37 pm
Re: Wing Jig for 24's
'I think that I may have stated some wrong.
Before you disassemble the wings, check the relationship between the first compression strut and the spars, you may find that the strut and the spars are perfectly square one to the other. That will also have the wing attach fittings right where they should be.
When I put my wings back together, I went through allot of extra steps in order to help elevate my confidence in what I had done.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]'
Before you disassemble the wings, check the relationship between the first compression strut and the spars, you may find that the strut and the spars are perfectly square one to the other. That will also have the wing attach fittings right where they should be.
When I put my wings back together, I went through allot of extra steps in order to help elevate my confidence in what I had done.
Bob Etter
PO Box 974
Tonopah, NV 89049
775-482-6820
rletter@citlink.net
[Non-text portions of this message have been removed]'