Well today I ordered my winter project, a 1/5th scale Sig Piper Cub J3. This is an 84.5" wingspan and weights about 7.5 lbs...I am expecting the build to come in nearer to 9 lbs with the modifications. I selected the Sig since it is the only one I could find with split wing. And Sig quality is well known. But the price point was a lot higher than the GP plane. I was unable to find any Super Cub Kit that I liked....Would of had to stick build it from plans, and I am nowhere near having the equipment or knowledge to take on that sort of build.
I have seen a dozen colors schemes and will go with the Military colors since 1) It will work on Warbird Day, 2) Super Cub was actually more associated with the military.
I will be adding full lighting, Robart articulating landing gear, Dubro Cub wheels.
Power system is still up in the air...But I am looking at RimFire .80 with 75Amp Pheonix Ice ESC, 6S6000, spinning a 15X6 prop...This is overkill for land, but is needed if I plan to later put floats.
To modify this to a Super Cub, I will be adding Flaps to the J3 and adding the landing headlight in the cowl. I am still trying to decide if I will put the cylinder heads poking out the cowl..A J3 thing that is not on the Super Cub...But can be made to look great if you put a bit of work into it.
Both tail surfaces will be Pull-Pull with the Servos up front for weight distribution.
I welcome any input on this...I have built a few plane in my life, but nothing as big as this. I will update with Pics as the build progresses....A lot of the Idea's I will be using I saw in post on other builds.
Steve
Sweet more Cubs ;D
Steve,
I'm not familiar with the Sig 1/5 scale Cub, but I like your choice over the Great Planes Cub as I believe the Sig Cubs are more accurate and generally much lighter.
I look forward to seeing the plane at TEMAC next summer.
Robert
I was nice to see Glenns Yellow Sig kit, it flew great! He just needs to paint the landing gear! ha ha!
Hey Steve I'm probably upgrading the motor in my revolver from a Rimfire .80 with ICE 75 to a Rimfire 1.20 with ICE 100.
If you're interested in a used Rimfire .80 and ICE 75 ESC let me know.
Ben
Well It is Day 1, Oct 22, 2012...There is 180 days until I leave for Ontario...So it must be done by then.
I have checked that all the parts are in the box, and I have read the instructions for the 55th time.
I don't have the Motor or Landing gear yet, so I will start with the Stabilizers and Elevator. Yes I am deviating from the plans right from the start ;D that way, it will be much easier to place the blame later when something doesn't fit.
The build is pretty much divided into the 1) Fuselage 2) Wings 3) Horizontal and Vertical Stabilizer, Elevator, and Rudder. I will only be changing the order they are built in, not the way they are built.
Here are the starter pics....
Also, I have decided to leave it as a J3 cub instead of the Super... With the Yellow skin... I may need to stick with the P51 for Warbird day.
I have ordered the electronics for the strobes and lighting today...And found a nice circuit to imitate a strobe. If this is not bright enough...I may need to go with real strobes.
Other things I am pondering...And would like any input I can get to help with the decision.
5S or 6S Motor will be a RimFire .80. I can get the thrust about the same with either battery...
Pros for 5S is that I already have, and the current will be lower, even with the bigger prop.
Pros for 6S is higher RPM, a bit more thrust...But would need to buy 2 new batteries at $80 per.
That's it for tonight...Have a good one...
Steve
Quote from: sts41 on October 22, 2012, 06:57:34 PM
Other things I am pondering...And would like any input I can get to help with the decision.
5S or 6S Motor will be a RimFire .80. I can get the thrust about the same with either battery...
Pros for 5S is that I already have, and the current will be lower, even with the bigger prop.
Pros for 6S is higher RPM, a bit more thrust...But would need to buy 2 new batteries at $80 per.
Steve
Hi Steve.
Although a bigger battery will help balance the model (I needed to put the battery through the firewall into the cowl to balance), my model flew very well on 4S. In fact, I don't think I ever used full throttle. I used an E-Flite 46 equivalent motor.
5S should be plenty.
The most important thing to remember when flying a Cub at scale (slow) speeds, is to use rudder when turning.
Yes, you may even want to add rudder mixed in with your ailerons. Another thing I needed to do on mine was set everything to very high rates to get enough responsiveness.
OK... Finished with the purchase of the new sled... Back to the build until the snow flies :)
I need to round off the edges of all the control surfaces. Does anyone have a neat rick to do a great job of this?
I will be trying a router bit for my Dremel, a hobby plane, and then just sandpaper....
But if anyone has a "You Just have to do it this way" trick.... Please let me know...Mostly looking for consistency.
Thanks All
I used a great planes flat 1 foot sanding tool. But to do the edges, I was using a foam sanding block with two grits. One fine and one a bit rough. Once I cut it down to the right shape, I then just fine sand it. Seems to work fine.
Steve i razor plane the edges down then sand
Take a block of pine. Drill a hole about 3/32" larger than the rounding you require. Cut the block on half so you have two half round grooves. Glue 150 grit in one and 220 in the other using carpenters glue and a dowel to clamp the sand paper. Use the plane to take some of the bulk off and finish with the sanding blocks. It goes very fast and you have an unbelievably uniform round edge.
Jack.
Quote from: Papa on December 04, 2012, 10:16:40 AM
Take a block of pine. Drill a hole about 3/32" larger than the rounding you require. Cut the block on half so you have two half round grooves. Glue 150 grit in one and 220 in the other using carpenters glue and a dowel to clamp the sand paper. Use the plane to take some of the bulk off and finish with the sanding blocks. It goes very fast and you have an unbelievably uniform round edge.
Jack.
Excellent tip!
Don't forget that trailing edges should not be rounded. Squared off trailing edges are more aero.
Ben
And nicely tappered to sharp edge is best (usually). The problem is, full scale have rounded TE's on their flying surfaces because of the tube contruction, although much smaller than the LE.
I always sand with a piece of 1x4x12 pine with a full sheet of 100 grit sand paper wrapped and stapled. I've used this for most of my sanding for 30+ years :) For large raduis sanding (like a large LE) I shape generally with a hobby plane then sand smooth, while checking the profile. Smooth curvature transitions is the key. In other words, take the curve of the wing LE sheeting (for example) into the LE strip, then accelerate the curve around the LE. Starting by knocking off the corners to a 45 degree surface first, gets you closer to the shape you want and also provides a surface to view for consistancy along the length before finishing off the rounding (if that makes any sense at all).
Robert
Some REALLY great Idea's... Will try them on some scrap wood and see what comes up.
Steve
You can make blocks with a shaped groove to match a leading edge. If you sand with a flat block you can get uneven sanding whereas with a shaped block you can only take off as much as the shape dictates.
jack.
Hey Steve! Any progress on the Cub?
Robert
I had been working on the Yak... But here is where I am at with the Cub..
I have built all the tail feathers and I am currently working on the Right Wing assembly.
It looks like it is going to take about 2 weeks for each wing. I have a little under 1 week on this one. If the weather stays this cold...Currently -35 with wind chill... I may get lots done over the weekend...I also took 2 days off after Superbowl weekend just for relaxing and building. 8)
Here is the pic so far:
Hopefully I can get all the Hardware bought... If so, I have more than enough time to get her done before we leave for Toronto... ;D But can I get the Cub and the Yak, and the P51 and the Syncro all in the wooden box... That is going to be the trick ;)
Steve
Loking great, Steve!
Keep at it. Warmer flying weather will be here before we know it.
When do you head West again?
Keep warm out there!
Robert
Should be there around April 22...
Steve
Update... So I came across some funds that were just sitting there doing nothing :) I have ordered the last of the big parts, so this puppy will be completed for this season. 8)
I have a great weekend coming up...will try and get lot's done.
My local Napa can match a color with a color match computer and mix me a spray bomb for the cowl.
Then there is just a few small items and we will be flying.
I will update with some pics after the weekend.
Steve
Terrific!
This is a great model airplane and I'm looking forward to seeing another Cub fill the TEMAC sky.
As long as it is Flying in the sky...and not crumpled on the ground :P
I had forgotten how much work goes into building one of these... I'm having fun, but man there is a lot of details...
So the power system will be a Electrifly Rimfire .80 motor:
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLWV7 (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXLWV7)
Swinging a 14X8 wooden prop. Can easily handle a 15X8 for floats.
This will give me about 142 onces of thrust for a plane that weighs in at about 144 onces. Just under a 1:1 ratio. The motor is a 500 KV so prop should have a max RPM of about 8500, and run at about 45 Amps and 800 Watts.
A Pheonix ICE 75 ESC:
http://www.castlecreations.com/products/phoenix_ice.html (http://www.castlecreations.com/products/phoenix_ice.html)
and a 5S 5000 battery, which should give me about 10 to 15 minutes of flight time.
This setup should run nice and cool even on the hottest days since nothing is being overworked.
For the servos... I have 4 of these monsters:
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14830 (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14830)
They are so smooth and it will all be controlled by a Futaba R6008HS receiver.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWVF5 (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXWVF5)
I have ordered the Robart 1/5 scale Cub landing gear and the Du-bro wheels with Cub wheel covers. And a tru Turn Prop nut for that little extra something....Other than that...I will be going with the standard Cub yellow with black accents.
I will leave the cockpit empty for this year... Next year I will do a bunch of work on that.
Steve
Ok...Job is coming along great...Need some advice from the Cub owners. Like most, this is designed for a gas engine. The area where the fuel tank goes is where the battery will be positioned...
What do you use to hold down the battery?
Since there is little room above the battery, velcro would be tough to both install and remove the battery. There is a fair amount of room on both sides, so larger batteries will be fine in the future. And there isn't much room for my big hands and a velcro strap.
I was thinking maybe velcro at the end of the battery and just one strap along the back... This is not an aerobatic plane... Shouldn't be a lot of force on the battery.
If anyone has any ideas....I am working on the body and it will be a few more days before I get there.
Thanks Steve
When I built mine, I needed nose weight, so I cut a large hole in the firewall, and extended a battery tray underneath the motor.
I was only using a 46-size motor and a 4-cell battery pack.
Since I was not planning on doing any aerobatics, I simply used velcro on the battery and battery tray, and the used the scale door instead of a hatch.
Hi All... work is going great. Still waiting for the motor, can't complete the nose without it. I have decided to make the "Nose Bottom" which is made of plywood, to be removable rather than glued in place. I will make a mount on there and secure the ESC in that spot..8 screws will hold it in place, and it can be removed if service to the ESC is needed.
Steve
Looking really, really nice, Steve! I'm jealous. :'(
First Piece to get it's skin.... :P
The Ultracote is not tacky like the Monokote... But it does stick nicely once the heat is applied...
I guess Ultracote it will be.... ;D
Steve
Nice! I like the door handle.
Robert
It actually works and locks the door closed...
Well.... working on the struts...First time seeing the plane with the wings on....It is big. ;D
Wow! So much building going on! Awesome Steve! Looking good!
Robert
Ok... One month to go and so much to do... I have received the motor and landing gear, along with the Cub wheels. I have three more rolls of covering coming, and should be in next week.
This week I will complete the fuselage, add the Tail feathers and preset all my hinges, and sand everything down. Also need to go have a couple of spray paint cans made to the proper color. Paint all the exposed surfaces that arent covered. Once I get the rest of the covering.... Finish that up and add all the electronics and controls....Maybe even the decals :) :P
Going to be a busy month.
Steve
The solid block motor mount is a good idea, and your landing gear looks great!
There is actually a big hole bored in the center. I can carve some more out if I need to for balancing. But it does make a good solid mount. The wooden props from HK look great...Hope they hold up as well as they look. :D
Steve
Need some help....The manual is kinda vague.
Ok, this has to do with attaching the Pull-Pull horn on the Rudder.
Here is the info I do have:
Before covering:
Notch out the bottom of Rudder to accept the Horn... Do not glue the horn on now, it will be done after the covering is on.
This was done.
Next , I covered the Rudder....
Now, in the manual, they say:
"After the rudder is covered, epoxy the molded Nylon Rudder Horn at the bottom. Let Dry."
Do I remove the covering where the horn goes...Or do I epoxy it over the covering? My bet is remove the covering...don't believe that epoxy would stick well to the covering.
Let me know if you are stating a fact, or opinion...Just want to get this right.
Thanks Steve
My opinion, epoxy to covering but drill a small hole through and through and pin it while the epoxy is setting.
Jack.
I hate to disagree with Jack, but it's standard prectice to remove the covering the get a solid bond joint. I would even rough up the inside surface of the plastic horn too.
Robert
Disagree all you want. My thought was that there is not much stress with this set up so it would not need a super bond.
jack.
I disagree ;D
Steve,
Found the time to read through your thread this a.m. Awesome build! You've got a winner! Did you order the LG directly from Robarts or did you get it through a retailer?
Thanks, I got it from GreatHobby. Where I am, not much as far as lhs. In fact, I am waiting for some blind nuts...Could not find any anywhere.
But, I will go into overdrive once I have them.
Steve
Well...Tonight is "Pin the Tail on the Plane". I am getting ever closer to putting a skin on this bird, and with only 2 and a half weeks left...I am in a time crunch.
The tail is the last part before I can start painting and covering...
The wings are completed except for the decals, I may wait until I am in Ontario to put the decals...If something goes wrong on the first few flights, it will be one less thing I have to buy.
Steve
That's looking really nice, Steve! It won't be long til we get to see it flying at TEMAC.
Ya know, all this building and reporting on the building that we're doing will make it so much more interesting to get together and fly this summer.
Great work!
Well started doing the covering... Outside corners are fine...But UGGG compound inside corners are not looking the way they do in the build manual. I may need to have a 10' zone that no one can enter and see the hack job I did on the tail. :o
Just before finishing the covering... I thought....Hey, maybe I should pass all my control cables and get the electronics in place...Some will be really hard to change after the plane is completed. Not impossible, but really hard. And I cannot see anyway to fix/change the rudder cables once the covering is on.
So I have some pics...Some far away, some close to the tail....Not sure how to make this look better. I will be doing one more shrink...but some of these ripples are overlapping material. I don't believe it will affect flight too much, and it is my first covering job...May just leave it until I need to remove the covering for some other reason.
Also...didn't know that digital servo's made so much noise....I was concerned until I went online and saw that this noise is pretty normal for these type of servo's.
Steve
More work done....Finished the RHS covering...It is MUCH nicer than some of the others I did...Darn Learning Curve. :-[
Got the Doors in and cut some of the cowl... Still need a cooling hole in the front, but the botton one and the Prop exit are cut. All the electronics are in and bolted down need to work on the battery tray, that should be pretty easy to build.
I get the spray paint mixed tomorrow...And I have some routing to do on the landing gear filler pieces....Then paint all those parts.
At this rate...Should be ready to do some engine running test by next weekend.
Steve
Looks great Steve, looking forward to see it maiden.
Jack.
Hey Steve. That looks like a great covering job... especially for your first!
Those inside corners where the fuselage blends to the fin are very difficult... almost impossible. The best approach is to NOT assume that the covering will shrink to just any curvature, but rather plan ahead and think of other ways to approach the fill that requires the least amount of shrinking possible. Even if it means the use of a couple of pieces. Try to join over a stinger or bulkhead, etc. to get good seam stability... next time... :)
Keep up the great work!
Robert
Very very nice. Attention to detail during covering takes huge patience but boy does it pay off.
(Personally, I have no patience, which I'm reminded of every time I look at one of my own covering jobs)
Ben
Ok...we are down to the details...I should be able to go ground test her this weekend..
All control surfaces are working...Motor is working, I am mostly working on paint and windows...
I will also complete the tail struts tonight, and start painting all of them. All windows should be in tonight also.
Also I checked...and she does fit in the travel box...Bonus :P
Steve
wow it looks great
Looks great Steve. Looks like your right on schedule.
Wow Another Great Build! I guess I am the slacker now! lol! :-X
So here it is... 8) All but the stickers. They will be added once I have a few flights in.
A few questions about balance for you people that have done Electric conversions... And also with the concern I have seen from others that balance is EXTREMELY important with a Cub.
Build instruction say:
3 1/2" back from the leading edge with an empty fuel tank.
Empty fuel tank being the operative word here... Maybe I am just splitting hairs, and I have nothing to worry about.
With everything in the plane... I am a touch nose heavy....Probably what I would see with a half tank of fuel...To me, this sounds perfect... Let me know what you think.
I was suppose to go ground test it this morning...But mother nature is a cruel B#%^%, :-X and I have 10 cm of snow out there.... >:( But will probably get to go sometime this week.
Steve
They say to balance with empty tank so that you will not run into a tail heavy situation as the fuel is burnt off. Flying slightly conservative cg nose heavy will be fine. Like 1/4-1/2 inch would be fine
Ok...It has been about 2 hours since I was done... And I just had to build something else.... An "Option" for my Cub 8)
It is a holder for my video camera.....
Steve
Slightly nose heavy is fine.
The most important thing about flying a Cub at low or moderate speeds is to turn using ailerons and rudder.
Turning with ailerons alone could cause a stall and a crash.
I've seen you fly many times, and, in my opinion, you are a good, steady and reliable pilot; I don't think you will have any problem.
Just remember to use rudder and ailerons in coordinated turns (both sticks gently in the same direction).
In fact, when flying my Cub, I often turn with rudder only, and then use opposite aileron to straighten out at the end of the turn.
Great job Steve! I look forward to seeing many "Touch and Goes" this Spring, Summer and Fall.
Glenn
Ok...Got every thing in the box... ;D Had to take the struts off the wings though :P
We are leaving Monday, the park will not be open until Monday...So we plan to show up on Wednesday or Thursday.
Steve
Steve, great looking build. The suspension on a full-scale cub sits inside canvas bags. You could make little black bags to cover the area of the elastic, or melt just the ends of a big piece of black heatshrink to mimic the look.
Great job.
Well I finally got to maiden this plane yesterday. This plane wants to take off... I took it up 5 times, getting it adjusted the way I like on my transmitter. The strong cross winds made it difficult, I had to watch the wings to make sure the plane didn't get flipped on landing.
I definitely need practice landing the tail draggers... but that is what the Yak is for and it shouldn't be long before I am doing regular Touch and Go's with the Cub.
All in All.. I am VERY happy with this one... Should really help with training for level steady flight and landing heavy planes. ;D
I may not be completely pleased with the covering... But it will do for now. Next will be to put all the decals on.
I will download all the Power figures, and give a final update to see how I did on calculating the electronics...
Thanks You everyone for all the help 8)
Steve
Sorry I missed the maiden... But I'm glad it went well
Congratulations Steve! I enjoyed watching all Bobby's maidens and especially yours as I've followed your build thread. Well done! :) ;) :D