Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
#1052
Thread Starter
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Re-Maiden complete. Five flights on the restored plane, all working well. Some minor adjustments to the flap mix and it was flying like it always did.
Having flown my Aero-Works Cub for so long I have really become accustom to how it flies. I can honestly tell ya, the Sig flies better!
I took a photo at the end of the day (Used my phone so it isnt the best). Lets hope it stays in one piece a little longer this time.
Thanks for all the support on this forum to get her rebuilt.
SunDevilPilot
Having flown my Aero-Works Cub for so long I have really become accustom to how it flies. I can honestly tell ya, the Sig flies better!
I took a photo at the end of the day (Used my phone so it isnt the best). Lets hope it stays in one piece a little longer this time.
Thanks for all the support on this forum to get her rebuilt.
SunDevilPilot
#1053
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Congrats on the re-maiden SDP! Really glad it went well and I wish you many happy flights with it!!! Now if I could just complete my Cub...
Take care,
David
Take care,
David
#1054
Banned
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
SunDevilPilot,
Congratulations on your success.
I remember the days when you had given up and we were encouraging you to do a repair job.
Glad of your success.
Zor
#1055
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Way to go SDP, happy for you. Now enjoy the fruits of your labors... BTW, your phone takes some pretty nice photos!
#1056
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Hi SDP. Ditto on the heartfelt congratulations on the rebuild of your Cub. It’s hard to believe it has been almost a year (April). It is a beautiful model and I hope to build one someday. Can you give us more details on its flying characteristics? In an earlier post, #851, you said your smaller 1/4 scale cub flew better than this one but this Sig cub flies better than the Aero-Works. I am wondering why that is.
But thank you again for taking the time to write this build thread. Your writing style is very easy to read and the pictures are plentiful and beautifully taken. I’ve enjoyed it very much and look forward to more in your Nieuport build.
But thank you again for taking the time to write this build thread. Your writing style is very easy to read and the pictures are plentiful and beautifully taken. I’ve enjoyed it very much and look forward to more in your Nieuport build.
#1057
Thread Starter
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
The 1/5th Scale Cub flies really light. It just floats along. The Sig 1/4 Cub, and the Aero-Works Sport Cub, take a bit more speed. You have to work a little harder at flying the bigger model Cubs smoothly. Not sure why... Sig really nailed it with the 1/5th...
Having gotten comfortable with the Aero-Works made me appreciate just how good the 1/4 Sig Cub kit flies. The Sig 1/4 feels somewhere between the 1/5th Scale Cub and the Aero-Works Cub.
Hard to describe....
The pride in the plane is much higher for both my Sig 1/4 and 1/5th Cubs. Anyone can have the Aero-Works.
SunDevilPilot
#1058
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RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
ORIGINAL: SunDevilPilot
The 1/5th Scale Cub flies really light. It just floats along. The Sig 1/4 Cub, and the Aero-Works Sport Cub, take a bit more speed. You have to work a little harder at flying the bigger model Cubs smoothly. Not sure why... Sig really nailed it with the 1/5th...
The 1/5th Scale Cub flies really light. It just floats along. The Sig 1/4 Cub, and the Aero-Works Sport Cub, take a bit more speed. You have to work a little harder at flying the bigger model Cubs smoothly. Not sure why... Sig really nailed it with the 1/5th...
Having gotten comfortable with the Aero-Works made me appreciate just how good the 1/4 Sig Cub kit flies. The Sig 1/4 feels somewhere between the 1/5th Scale Cub and the Aero-Works Cub.
Hard to describe....
The pride in the plane is much higher for both my Sig 1/4 and 1/5th Cubs. Anyone can have the Aero-Works.
SunDevilPilot
#1059
Thread Starter
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Whipped up a caddy for my 24V power supply. Just felt like making something with my woodworking tools. I even busted out the wood lathe to turn the handle, which was made from a block of coyote wood left over from a previous project.
The power supply will be strapped into the caddy when the polyurethane dries keeping it safe and easy to carry around.
The handle got a tenon turned into each end setting the proper spacing between the sides.
Unnecessary but fun!
SunDevilPilot
The power supply will be strapped into the caddy when the polyurethane dries keeping it safe and easy to carry around.
The handle got a tenon turned into each end setting the proper spacing between the sides.
Unnecessary but fun!
SunDevilPilot
#1060
Join Date: Apr 2010
Location: Clinton,
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RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
It may be insignigicant because of the area of the damage, but I noticed that there was no damage in areas that you laminated balsa. Examples are the horizontal stab and the wing tips.
Congratulations!
Congratulations!
#1061
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Location: SorrentoBritish Columbia, CANADA
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RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
I finally got around to putting the Robart gear on my Sig 1/4 Cub ..What a difference this makes to an already wonderfull plane .. It only took me about 6 hrs so I don't know why I kept putting it off...I can hardly wait to try it out...I feel like the little kid with the new running shoes.. This gear is 2.5" narrower than the original gear was . I hope that doesn't have a negative effect on its take off roll... I do know that when I put this gear on my GP 1/5 Fabric covered Cub it improved how that Cub handled so much that it was like a different plane on the ground...
#1062
Thread Starter
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
I'm still playing with the metal lathe I recently got and I am trying to learn as much as I can. Today's project was to make some wing studs. New skill, tapping using the lathe to align the tap.
Worked perfect.
Now I can install the wings, minus the struts, without tools. The studs were turned from a piece of 3/4 aluminum. The center was tapped with 8-32 threads and a bolt was permanently installed with red locktite through the middle.
SunDevilPilot
Worked perfect.
Now I can install the wings, minus the struts, without tools. The studs were turned from a piece of 3/4 aluminum. The center was tapped with 8-32 threads and a bolt was permanently installed with red locktite through the middle.
SunDevilPilot
#1063
Banned
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
ORIGINAL: SunDevilPilot
I'm still playing with the metal lathe I recently got and I am trying to learn as much as I can. Today's project was to make some wing studs. New skill, tapping using the lathe to align the tap.
Worked perfect.
Now I can install the wings, minus the struts, without tools. The studs were turned from a piece of 3/4 aluminum. The center was tapped with 8-32 threads and a bolt was permanently installed with red locktite through the middle.
SunDevilPilot
I'm still playing with the metal lathe I recently got and I am trying to learn as much as I can. Today's project was to make some wing studs. New skill, tapping using the lathe to align the tap.
Worked perfect.
Now I can install the wings, minus the struts, without tools. The studs were turned from a piece of 3/4 aluminum. The center was tapped with 8-32 threads and a bolt was permanently installed with red locktite through the middle.
SunDevilPilot
Edited to add he following paragaph
I am now figuring that you have nuts ofsome kind in the wing roots andyou turn the aluminum pieces by hand inside the cockpit to screw in the wing roots.
Zor
#1064
Join Date: Aug 2008
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RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
Maybe this was easiest way to bolt wings. Sorry but those bolts does not go with this beautiful plane.
Also maybe, it is better to make (buy) plastic bolts. They handle much better vibrations.
Also maybe, it is better to make (buy) plastic bolts. They handle much better vibrations.
#1065
Thread Starter
RE: Sig 1/4 J3 Kit converted to PA-18 Super Cub (Build)
You got it right. There are blind nuts installed in the root ribs. You slide the wings on and from inside the fuse tighten up the bolts. The aluminum I added makes each bolt its own screwdriver. Function over Form is my method. I also dont hide control linkage because functionally it seems better exposed.
Much easier to work with than reaching in there with an allen key.
Attached is a photo of the root rib showing the bolt holes where the blind nuts are.
And... No need for plastic, there is no vibration, it's electric.
The plane has always had the bolts, they just needed an allen key to tighten them before I added the aluminum.
Also attached is a photo of the original bolt setup with the wings roots still attached to the fuselage. (Ouch! Photo taken during the repair process!)
SunDevilPilot
Much easier to work with than reaching in there with an allen key.
Attached is a photo of the root rib showing the bolt holes where the blind nuts are.
And... No need for plastic, there is no vibration, it's electric.
The plane has always had the bolts, they just needed an allen key to tighten them before I added the aluminum.
Also attached is a photo of the original bolt setup with the wings roots still attached to the fuselage. (Ouch! Photo taken during the repair process!)
SunDevilPilot
#1067
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Join Date: Dec 2013
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The 1/5th Scale Cub flies really light. It just floats along. The Sig 1/4 Cub, and the Aero-Works Sport Cub, take a bit more speed. You have to work a little harder at flying the bigger model Cubs smoothly. Not sure why... Sig really nailed it with the 1/5th...
Having gotten comfortable with the Aero-Works made me appreciate just how good the 1/4 Sig Cub kit flies. The Sig 1/4 feels somewhere between the 1/5th Scale Cub and the Aero-Works Cub.
Hard to describe....
The pride in the plane is much higher for both my Sig 1/4 and 1/5th Cubs. Anyone can have the Aero-Works.
SunDevilPilot
BTW excellent work on the original and repaired Cub. I knew you would be happy if you repaired it. If you had thrown it away you would have moved on and probably not looked back but if you rebuilt it you would be very happy you didn't!!! It's good you had subscribers to encourage you.
Last edited by Ingrahal; 02-27-2014 at 08:03 PM.
#1068
Senior Member
Your wing bolts look excellent, I know the pain of reaching in with the wrench, especially on the right wing where you have to reach in and back. it's the most time consuming part of field assembly for me.
#1069
SDP thank you for this very informative build, I like your building style and classic fit up of parts. While I haven't read the whole thread yet but will, I'm pleased you included the Balsa kit differences with the Sig, I'm building the Balsa USA kit hoping to get as scale in details as can be expected on the super cub from a J3 kit, I know there is going to be things to alter and I have been studying the 1/3 scratch build plans of this plane which I have already and have alot of Ideas on changes. I'm sure your build will aid me in some decisions I will have to make.
Sorry about the crash, I haven't got to that yet but am intrested in what caused it and will address that when I build mine if need be.
Great thread and a very nice build, thank you,
Leroy
Sorry about the crash, I haven't got to that yet but am intrested in what caused it and will address that when I build mine if need be.
Great thread and a very nice build, thank you,
Leroy
#1070
My Feedback: (49)
Leroy Gardner Quote:
Sorry about the crash, I haven't got to that yet but am interested in what caused it and will address that when I build mine if need be.
Great thread and a very nice build, thank you,
Leroy[/QUOTE] If I remember correctly (short term memory being as it is) I believe SDP mentioned some thing about running out of Air Speed, Altitude and Ideas, Pretty much in that order. SDP see ya in 31 days ... say Hi to the Big Fella for me. Keep the greasy side up. OH don't that applier anymore with "Lectrics"
Sorry about the crash, I haven't got to that yet but am interested in what caused it and will address that when I build mine if need be.
Great thread and a very nice build, thank you,
Leroy[/QUOTE] If I remember correctly (short term memory being as it is) I believe SDP mentioned some thing about running out of Air Speed, Altitude and Ideas, Pretty much in that order. SDP see ya in 31 days ... say Hi to the Big Fella for me. Keep the greasy side up. OH don't that applier anymore with "Lectrics"
#1071
Thread Starter
Operation Get The Lead Out has begun.
I'm really happy with the Cub but every time I fly it I think it feels a little too heavy. So I am going to try and get a pound out of the plane by taking at least 4 ounces out of the tail. If you go with 1oz in the tail equals 3 oz in the nose ratio it should be possible. If I can get my 4oz then I should be able to get 12 in the nose. 16oz in a pound.
I got the thread cutting attachment when I originally purchased my Sherline Lathe. Honestly, I was a little intimidated by it and didn't think cutting threads would be very easy. I was really wrong, it was super easy.
The only thing I had to look up was the diameter of an 8-32 bolt (.1640) and I was all set. Using the Sherline Manual to set the gearing and there was no issue.
Everything was done on the lathe, with exception of the "Screwdriver" slot, which was done with a slitting saw on the mill.
Aluminum I used is 6061-T6 which is 1/3rd the weight of the steel bolts they replaced.
I think the real weight loss will come when I replace the 4-40 tail brace wires, which is next.
Couple photos of the process.
FYI, I looked all over the internet for Aluminum bolts, at least 1 3/4" long and I was not able to find any. So, I made them.
SunDevilPilot
I'm really happy with the Cub but every time I fly it I think it feels a little too heavy. So I am going to try and get a pound out of the plane by taking at least 4 ounces out of the tail. If you go with 1oz in the tail equals 3 oz in the nose ratio it should be possible. If I can get my 4oz then I should be able to get 12 in the nose. 16oz in a pound.
I got the thread cutting attachment when I originally purchased my Sherline Lathe. Honestly, I was a little intimidated by it and didn't think cutting threads would be very easy. I was really wrong, it was super easy.
The only thing I had to look up was the diameter of an 8-32 bolt (.1640) and I was all set. Using the Sherline Manual to set the gearing and there was no issue.
Everything was done on the lathe, with exception of the "Screwdriver" slot, which was done with a slitting saw on the mill.
Aluminum I used is 6061-T6 which is 1/3rd the weight of the steel bolts they replaced.
I think the real weight loss will come when I replace the 4-40 tail brace wires, which is next.
Couple photos of the process.
FYI, I looked all over the internet for Aluminum bolts, at least 1 3/4" long and I was not able to find any. So, I made them.
SunDevilPilot
Last edited by SunDevilPilot; 05-19-2015 at 06:12 PM.
#1074
Thread Starter
I knew when I posted those photos you'd enjoy seeing the chips all over the place. However, you can rest assured those were promptly cleaned up and the lathe is once again in pristine condition, ready for next time.
SunDevilPilot
SunDevilPilot