CARF-Models 2013 Series 3.1m Extra 330SC
04-19-2013, 03:12 PM
#26
RE: CARF-Models 2013 Series 3.1m Extra 330SC
The leading and trailing edge locations for the hatch had been determined. Measure the same distance down from the leading edge of the yellow bars to keep everything square. Lay the ruler across those two points and cut the line just a little short of the blue tape so you can add a corner if you want.
Do the same for the trailing edge of the hatch. Measure down the same distance from the leading edge of the yellow bar and cut the line.
Do the same for the trailing edge of the hatch. Measure down the same distance from the leading edge of the yellow bar and cut the line.
04-19-2013, 03:15 PM
#28
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I found some scrap 1/8†lite ply to cut some corners for the hatch screws. Cut them so the grain is on the 45. That will keep the screw from splitting the wood.
The corners and screws for both wings weighed .2 ounces. I’ve added .1 ounce to each wing.
The corners and screws for both wings weighed .2 ounces. I’ve added .1 ounce to each wing.
04-19-2013, 03:16 PM
#29
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I glued the corners in with foam safe CA (they weren't drilled yet).
Give the CA a good 5 minutes to make sure it's cured. Set the hatch back on. I used the little hand drill and a 1/16" drill bit to drill for the hatch screws. Start in one corner and add the screw. Then go across 45 to the other corner and drill and add a second screw.
Drill each hole and put the screw in before you drill the next hole. In just a few minutes the hatch is perfectly attached. I used some #2 x 9/16 hex head servo screws from Micro Fasteners.
Give the CA a good 5 minutes to make sure it's cured. Set the hatch back on. I used the little hand drill and a 1/16" drill bit to drill for the hatch screws. Start in one corner and add the screw. Then go across 45 to the other corner and drill and add a second screw.
Drill each hole and put the screw in before you drill the next hole. In just a few minutes the hatch is perfectly attached. I used some #2 x 9/16 hex head servo screws from Micro Fasteners.
04-19-2013, 03:17 PM
#30
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I checked the holes for the aileron servos in the servo tray. They are large enough for the servos so no trimming will be necessary. I'm going to attempt to install the inboard aileron servo from the wing root with no hatch.
Time to install some aileron servos!!
Time to install some aileron servos!!
04-20-2013, 08:28 AM
#31
RE: CARF-Models 2013 Series 3.1m Extra 330SC
ORIGINAL: Dean Bird
I started by adding a hatch for the outboard aileron servo.
I started by adding a hatch for the outboard aileron servo.
While I was doing this I had sent an email to Andreas asking if the 122"Extra 330SC could have the hatches installed by the factory.I was jealous of the new 102" Extra 330SC that already had them installed. What I didn't realize is that on the 102" plane the servo attaches to the hatch. I wouldn't want that on this size plane with the size of the aileron we're pushing with 500 ounces of torque on a servo. Here is the information from Andreas.
~~~~~~
The servo access of the 3.1m is of completely different nature than of the 2.6m. On the 2.6m the servos mount to the hatch and the hatch has to be mounted structurally strong to the wing skin.
On the 3.1m such a hatch design is not necessary. It neither has to carry any load, nor has it to be removable quite often for access. That is because the servos are mounted structurally sound in the ribs. For the large ailerons this is definitely the better engineered way to mount the high torque servos.
For access, we always lived the philosophy that an Xacto knife can solve this problem in literally 20 seconds. Put a square of masking tape (maybe 3" x 3") on the area where you want to open the access, draw a pencil line on the tape precise enough to follow with an Xacto knife. Then poke the knife in, cut along the line (it will cut the foam sandwich like butter) and pop the hatch out. Remove the tape. Done. I guarantee this doesn't take more than 1 minute. And it doesn't add a single gram to the structure.
Once you have installed and set up your servo, you take the hatch and press it into its old position. You will see that you barely need to hold it with anything because the knife cut hasn't left any gap, so the hatch is held in place. You can take a thin, high quality clear tape from the office supplies and stick it on top of the cut and that hatch isn't going anywhere unless you want to take it off for servo maintenance. You barely see it, it doesn't weaken the structure, you haven't added weight except 20 cm of clear tape, what more do you wish for? And it took a few minutes at most.
The ones who want to mount the servo without a hatch can still do so. In Europe there are quite a few.
~~~~~~
Excellent information from the designer of the plane. Thanks, Andreas!!
I see why it's optional and see why it can be just a quick access and tape it back on. I think Andreas suggesting to cut through the masking tape is a great tip. That may keep the line a little cleaner. I would still add a couple small balsa blocks to hold it in place while you tape the hatch back on.Perfect!!
04-22-2013, 05:21 PM
#32
RE: CARF-Models 2013 Series 3.1m Extra 330SC
The first of the "New 2013 series modifications and improvements" is the "Aileron hinging". I asked Andreas what that meant. He told me, "Previously it was one long hinge pin through the center hinged aileron. The aileron therefore had to have a long spar. Now it is 4 separate hinges with only short pins, no spar anymore. The aileron is not so easily removable any more but it saves approximately 100 gram in each wing."
Cool. Since I'm shooting for no less than 41 pounds and no more than 42 pounds, any help from the designer to save weight is good. A little over 7 ounces removed from the plane.
When I asked Andreasabout the "4 separate hinges with only short pins" he told me, "the short tubes are squeezed with a pair of pliers on both ends, when installed, so that they actually press slop free into the outer bearings. That way they can't create wear because there is no movement, and they will not be able to slide out. We were testing this method the full last year's flying season with Niklas Roth, a young German pilot."
Here are the pictures of the "4 separate hinges with only short pins".
04-22-2013, 05:23 PM
#33
RE: CARF-Models 2013 Series 3.1m Extra 330SC
Before mounting the outboard servo I had to add a hole for the aileron extension. I let Andreas know and the hole for the extension will be milled in the rib on their future builds.
The servos dropped right in these holes. The holes in the horizontal stabilizers had to be opened up to fit the servos. That will also be corrected on the future builds so that the 8711/8911 and BLS152 size servos will drop right in the servo openings in the stabilizer too. Thanks, Andreas!!
I used the round file in the little hand drill to make sure the servo screw holes were straight and just a little larger to make the screws possible to install.
I used the round file in the little hand drill to make sure the servo screw holes were straight and just a little larger to make the screws possible to install.
After getting one hole the perfect size, I could see how far down to file the hole. That made it easy to do the other three the same size.
04-22-2013, 05:24 PM
#34
RE: CARF-Models 2013 Series 3.1m Extra 330SC
On the second wing panel I decided to just drill out the servo screw holes a little larger. The 1/16" drill bit dropped into the hole, so I drilled all four holes with a 5/64" bit in the little hand drill.
I put the screws in all four holes without the servo. It's a little easier to put them in the first time without the servo. Once they're in once, they're easier to reinstall.
The hole for the servo needed a little trim in one corner. It was easy with the hatch. 
04-22-2013, 05:26 PM
#35
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I'm using the AirWild Hobbies MLP servo arms on this plane. I chose the 1.5" arms since I'm only looking for 25 to 30 degrees maximum throw on the ailerons.
I drilled at tapped them at 1.25" just in case they end up with too much throw.
04-22-2013, 05:28 PM
#37
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I added a "wire keep" toprotect the plywood rib from rubbing the servo wire. I added another one in the hatch area to make sure the servo wire can't get caught on the hatch screw.
I used the supplied ball link for the aileron control horn, a 3.5" titanium turnbuckle, and a Kavan 4-40 ball link (it's an 1/8" shorter than a Dubro)for the servo arm. The key is that the servo arm is 90 degrees from the wing surface with the aileron centered when the linkage is complete. That's a great way to set up all the servos. It doesn't matter where the servo is mounted, just get the arm at 90 degrees to the wing surface. The starting point is the same for every servo that way.
04-22-2013, 05:30 PM
#38
RE: CARF-Models 2013 Series 3.1m Extra 330SC
It was time to mount the inboard aileron servos. The servoisabout 12" inside the root rib of the wing. I had been enlarging the holes for the servo screws but I wanted to try mounting the inboard servos without a hatch.
I asked Andreas it maybe the servo screw holes were intentionally being made smaller so that my little Futaba screwscould be used. If the JR screws or the supplied 2.9mm screws were used then the holes could be made bigger? Is that what was happening?
Nope. Andreas told me, "for a 2mm hole you need a 2.9mm self tapper screw to work. The Futaba screws are 2.2mm which is definitely not enough grip in a 2mm hole. Do not use smaller screws than the 2.9mm included in the kit. Not the JR and not the Futaba!"
I told him I had to enlarge the holes to get the 2.9mm screws to install. He said, "I understand that with a short screwdriver and the handling through the hatch you don't have the force to put axial pressure on the screw to "bite". That's why I always also have an extended screwdriver (cut a cheap one and solder/Aeropoxy it into a brass tube). It allows you to apply the pressure through the root rib to make the screw "bite"". I decided to try that for the inboard aileron servo.
Ace Hardware was selling a 2 foot piece of 1/2" PVC for 99 cents. I thin CAed a little phillips screwdriver into the end of it. A small piece of Tygon tubing made it easy to hold the screw.
The 2 foot extensionwould have been enough to reach the outboard aileron servo.
04-22-2013, 05:32 PM
#39
RE: CARF-Models 2013 Series 3.1m Extra 330SC
Before I mounted the inboard aileron servo I had to create the extension for it. I had decided to take on the challenge of creating my own custom length extensions for this plane. No extra weight for multiple extensions that are up to 6" too long. I'd get the minimum length required and the minimum weight being added for all the extensions. Plus it seemed to be more affordable to make your own. A win, win, win situation.
I purchased the AirWild Hobbies Servo Extension DIY kit and the Wild gauge that is a tachometer, voltmeter, and measures continuity. They warn you that there is a learning curve. It was NOT fun making the connectors for these extensions. 
I got them completed on the servo end and used heat shrink tubing on the connection since it will be concealed inside the wing.
I got them completed on the servo end and used heat shrink tubing on the connection since it will be concealed inside the wing.
04-22-2013, 05:50 PM
#40
RE: CARF-Models 2013 Series 3.1m Extra 330SC
With the inboard servo dropped down into the wing, the bottom corner of the servowith the power lead will go into the hole first. You need to push up on thatcorner of the servo to get it level enough to drop into the hole in the servo tray. I used a long screwdriver inserted through the outboard servo hatch to get the inboard servo level so it would drop into the hole in its servo tray.
04-22-2013, 05:52 PM
#41
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I mounted the inboard servo using the long screwdriver that Andreas recommended to get the "bite" on the 2.9mm screws. It worked. The screws were quickly installed.
I added the extension for the outboard servo and put heat shrink tubing on the connection. The previously created connection for the inboard servo is hanging on the right side.
I dropped in a bare wire from the root rib and taped it to the two servo extensions (also with no connector yet).
I pulled the extension up through the inboard aileron servo rib that has the hole for the extensions to come through. Both servo extensions have about 18" of wire left and no connector until I figure out what and where those wires are going to connect.
04-22-2013, 05:53 PM
#42
RE: CARF-Models 2013 Series 3.1m Extra 330SC
All the servo linkages were prepared to put the servo arm at 90 degrees to the wing surface.
I needed to open upspace for the servo arms and ball links to move. I used the tip Andreas gave us on putting tape on the wing surface and cutting through the tape. It worked very well. It's very easy to control the cut and the cut line stays nice and clean.
If I were to do this again, I would just cut the hatch out using the tape under the cut lines, add a couple small balsa blocks underneath to support the hatch, and then tape it back on after I was done. It would be very quick, easy, and clean.
If I were to do this again, I would just cut the hatch out using the tape under the cut lines, add a couple small balsa blocks underneath to support the hatch, and then tape it back on after I was done. It would be very quick, easy, and clean.
04-22-2013, 05:54 PM
#43
RE: CARF-Models 2013 Series 3.1m Extra 330SC
On the second wing panel the screws weren't going in so easy. I kept trying and they wouldn't turn. I looked at my little #0 phillips screwdriver and the screws had eaten up my screwdriver.
It's key for turning these 2.9mm screws that you have a high quality screwdriver that is the correct size. Only then will the phillips screwdriver have the "bite" to turn the screws.
I headed off to Ace Hardware with a screw and got a #1 phillips screwdriver and a smaller piece of PVC. The new #1 screwdriver worked great. If you've got the correct tool, things go very quickly. 
04-22-2013, 05:56 PM
#44
RE: CARF-Models 2013 Series 3.1m Extra 330SC
The second of the "New 2013 series modifications and improvements" is the "new servo positions". The outboard aileron servo has been moved from the 70% out position to the 50% out position.
The first improvement took over 7 ounces out of the plane. This modification takes the outboard servo and moves its mass closer to the center. Even better snap rolls!!
The first improvement took over 7 ounces out of the plane. This modification takes the outboard servo and moves its mass closer to the center. Even better snap rolls!!
04-25-2013, 04:03 PM
#46
RE: CARF-Models 2013 Series 3.1m Extra 330SC
With the stabilizers and wings complete, I went back to the beginning of the instruction manual to start installing things on and in the fuselage.
The first thing to install is the tail wheel assembly.I got a titanium style with direct drive from J&J Tailwheels as a Christmas gift while I was still researching what I wanted and hadn't decided which airframe I wanted to fly.I was thinking the titanium style was the lightest.I was thinking the direct drive was the simplest to install.It is the absolute incorrect tailwheel assembly for this plane.
It was a gift so I decided to make it work.There are titanium assemblies like this one and carbon leaf spring assemblies.This fuselage has a flat bottom at the rudder post and is perfect for mounting a leaf spring type assembly.
I have the direct drive option instead of the traditional style that uses springs from the rudder control horn to drive the tail wheel steering.The bottom of a composite rudder has no structure so it isn't built for mounting a connection for the direct drive of the tailwheel.
Get a leaf spring tailwheel assembly with traditional style steering and you can mount it in a matter of minutes.It took me about 90 minutes to get this one mounted.
The mounting brackets in the first picture were too wide for the fuselage bottom.I ended up using 1/4" cable clamps and some cool black #8 x 1/2" screws for the attachment to the fuselage.
04-25-2013, 04:04 PM
#47
RE: CARF-Models 2013 Series 3.1m Extra 330SC
The screws are going into a plywood plate in the bottom of the fuselage.The front of the rudder post is 1" from the rear of the plane and the plywood plate extends for another 4.5" past the front of the rudder post.
The part of the titanium that rests on the fuselage 3.25" long, so I decided to mount the wire so the bend away from the fuselage is just slightly in front of the rudder post.
Drill a 1/4" hole for the vertical and the position is set.
04-25-2013, 04:05 PM
#48
RE: CARF-Models 2013 Series 3.1m Extra 330SC
The bend from the vertical part of the wire to the part that rests on the fuselage has a small radius.My little round need file in the hand drill takes a little off the corner on the fuselage to match the radius on the wire.
When you get enough taken off, the vertical wire should slide in and the wire rests perfectly on the bottom of the fuselage.
04-25-2013, 04:07 PM
#49
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I really wish I was using a leaf spring style tail wheel assembly. 
I needed support for the vertical wire.I took a 1.25" length piece of a 1" dowel and turned it into an oval.I marked the center of the oval and then slid it through the rudder post.
I set it off to the side.You can see the hole in the plywood plate for the vertical part of the wire.
I used a long, thin screwdriver and put 15 minute epoxy in an oval shape around the hole.I used hemostats to grab the wood oval and place it over the 1/4" hole in the bottom of the fuselage.
My beautiful wife was very helpful and spotted from underneath with a flashlight.She told me when I had the black dot in the center of the wood oval centered in the 1/4" hole in the bottom of the fuselage.
The wide part of the oval went across the fuselage since that is the direction the wire will be trying to twist.
04-25-2013, 04:08 PM
#50
RE: CARF-Models 2013 Series 3.1m Extra 330SC
I let the 15 minute epoxy cure overnight.Today I turned the fuselage upside down and drilled the 1/4" hole in the fuselage through the wood oval I added.
I wicked thin CA into the screw holes and the 1/4" hole to harden the wood.
The titanium style tailwheel is mounted.