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Old May 23, 2014, 10:28 PM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
North AL, USA
Joined Nov 2009
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Yep, BTW thanks for the PM too!

Picked up another sheet of 1/8 balsa and Gorilla Glue. I am reshaping the flap trailing edge since I lengthened the tip chord. I'll build them up like the ailerons. From there it will be time to place the servos and to work out hinge positions for the ailerons and flaps.

The DX 7 still needs programming too, so I better get to that so I can power up and center the servos.
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Old May 25, 2014, 08:27 AM
A Day @ a Time - Matt. 6:25-34
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North AL, USA
Joined Nov 2009
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I just remembered I use a GWS EP-1060 on a Piranha (one of Tony' s outstanding designs), so very carefully tested this prop. With a 2200 mah 3S at around 80% charge, it produced 150 watts at 14 amps, well under the maximum of 17 for the motor. With a fully charged battery this setup would likely exceed the motor rating.
A good test nonetheless; with the 9050 x3, it has a more aggressive pitch and I think the numbers will come out close to what I saw. The HURC site shows the Firepower 400 Sport with the 9050x3 drawing 17 amps, with a recommendation to avoid constant wide-open throttle.
I think this prop will get me into a better range, but probably not 90 watts per pound - more like 75. I can live with that, especially with the better wing loading by increasing the chord at the tips (19 %) more area.
I'm glad I designed this bird to take 9 inch props!
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Old Jun 04, 2014, 06:20 PM
A Day @ a Time - Matt. 6:25-34
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North AL, USA
Joined Nov 2009
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Still haven't ordered new props yet, just working on the flaps. Had to do a bit of surgery and move one of the ribs inboard by 1/4 inch to get consistent flap width (the joys of scratch building).
I did some calculations on the C rating and for testing the power setup I have a 2200 mah 3S 30C that when fully charged will provide sufficient draw to check the amperage with the new props. I'll hold off on a battery until I get closer to completion.
Off on my annual trek to Baja California Mexico on the 14th. Probably not a lot of progress until after the 21st of June.
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Old Aug 24, 2014, 09:57 PM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
North AL, USA
Joined Nov 2009
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Bump... Actually just a gentle nudge on this build thread, it is still alive.

Finally got the DX7 programmed today so I could power up the receiver and center the servos. What a nice radio. She'll be talking to an orange RX3S receiver with axis stabilization; all the guys in my club that have them like them.

Mounted servos for the ailerons, beveled the ailerons for movement, fitted hinges in the wing and the ailerons. They fit nicely. I will post pics later, not much to look at now.

Flap servos are next; the flaps are already shaped and hinge slots cut out. Beyond that, I need to decide what to do next. Might be getting the ESCs mounted in the nacelles and wired up and running extension wires for the ailerons and flaps. After that I can skin the top inboard section as I already have the spar glued in. The outer panel I'll skin after gluing to the center section.

Hopefully I can pick up the pace a bit on this one. Been difficult to get out into the shop lately.

Whoever can play Taps, please do it for my Sensei. Put in a brand new motor and ESC, she just nosed over and died yesterday - cartwheeled, ended up with 2 90 degree angles in the fuselage . No control whatsoever. It never has been the same since I put it in a tree (it came out and actually landed on the runway but had a lot of damage). I think the receiver had something wrong with it. Sold it for a 20-spot who needed a "rebuilder" for his grandson. Instead of fighting that I can concentrate on the 4-0-4. One of those planes you just get tired of messing with... I have picked up a couple of Piper Cubs, and built a Blu Baby, a Blu Between and a Piranha to bash around so still plenty to put in the air.

Lastly, seeing some amazing craftsmanship in this forum, keep up the great work!
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Old Aug 24, 2014, 10:38 PM
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United States, SC, Charleston
Joined Mar 2007
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Quote:
Originally Posted by ruff1 View Post
Bump... Actually just a gentle nudge on this build thread, it is still alive.

Finally got the DX7 programmed today so I could power up the receiver and center the servos. What a nice radio. She'll be talking to an orange RX3S receiver with axis stabilization; all the guys in my club that have them like them.

Mounted servos for the ailerons, beveled the ailerons for movement, fitted hinges in the wing and the ailerons. They fit nicely. I will post pics later, not much to look at now.

Flap servos are next; the flaps are already shaped and hinge slots cut out. Beyond that, I need to decide what to do next. Might be getting the ESCs mounted in the nacelles and wired up and running extension wires for the ailerons and flaps. After that I can skin the top inboard section as I already have the spar glued in. The outer panel I'll skin after gluing to the center section.

Hopefully I can pick up the pace a bit on this one. Been difficult to get out into the shop lately.

Whoever can play Taps, please do it for my Sensei. Put in a brand new motor and ESC, she just nosed over and died yesterday - cartwheeled, ended up with 2 90 degree angles in the fuselage . No control whatsoever. It never has been the same since I put it in a tree (it came out and actually landed on the runway but had a lot of damage). I think the receiver had something wrong with it. Sold it for a 20-spot who needed a "rebuilder" for his grandson. Instead of fighting that I can concentrate on the 4-0-4. One of those planes you just get tired of messing with... I have picked up a couple of Piper Cubs, and built a Blu Baby, a Blu Between and a Piranha to bash around so still plenty to put in the air.

Lastly, seeing some amazing craftsmanship in this forum, keep up the great work!
Sorry to hear about your Sensei Kev. . . Get back to your 404 soon!
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Old Aug 27, 2014, 10:32 PM
A Day @ a Time - Matt. 6:25-34
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North AL, USA
Joined Nov 2009
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Ailerons Fitted...

OK, a wee bit of progress...

Glued in the servos last night (definitely NOT removable). Tonight I dry fitted the ailerons onto the panels, used my flying buddy's z-bend pliers and cut the control rods to size.

I'm satisified with the outcome on these. First movement test shows I get about 3/4 and inch up and down with the default 100% rate each way on the channel.

Flaps are next; I still need to fit the servos.
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Old Aug 27, 2014, 11:19 PM
Up-Out-&-Gone
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Originally Posted by ruff1 View Post
OK, a wee bit of progress...

Glued in the servos last night (definitely NOT removable). Tonight I dry fitted the ailerons onto the panels, used my flying buddy's z-bend pliers and cut the control rods to size.

I'm satisified with the outcome on these. First movement test shows I get about 3/4 and inch up and down with the default 100% rate each way on the channel.

Flaps are next; I still need to fit the servos.
Ailerons are looking good Kevin! Even the smallest bit of work on a build is better than no work.
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Old Sep 14, 2014, 09:33 PM
A Day @ a Time - Matt. 6:25-34
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North AL, USA
Joined Nov 2009
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Progress On Wing - Checking Skin on Fuselage

Chugging away...

Today I wired up the ESCs and most of the wiring through the center wing panel. I need to order some Y connectors for the flaps, rudder/nose wheel and gear. The ailerons have their own connection on the receiver so I don't need one there.

Cut out and shaped the skin for the wing center panel as well as the top front of the fuselage. I'm happy the way they came out. I didn't have to score on the underside of the top wing skin, but had to for the fuselage. A compass point seemed to work well. There will be some bend spots to sand flush on the fuselage skin but shouldn't take much.

I really like the way the FFF shapes up for skin. From a shaping perspective my biggest concern right now is figuring out how to shape the nacelles. That can wait until I get the center panels skinned. I have some solid foam pieces that might work well and hot wire to get them to rough shape.

Once I have the remaining parts in hand, I'll be able to join the outer wing panels to the center panel then put the skin on. Fuselage in the aft section will be tricky too.
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Old Sep 14, 2014, 09:46 PM
Up-Out-&-Gone
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United States, SC, Charleston
Joined Mar 2007
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Originally Posted by ruff1 View Post
Chugging away...

Today I wired up the ESCs and most of the wiring through the center wing panel. I need to order some Y connectors for the flaps, rudder/nose wheel and gear. The ailerons have their own connection on the receiver so I don't need one there.

Cut out and shaped the skin for the wing center panel as well as the top front of the fuselage. I'm happy the way they came out. I didn't have to score on the underside of the top wing skin, but had to for the fuselage. A compass point seemed to work well. There will be some bend spots to sand flush on the fuselage skin but shouldn't take much.

I really like the way the FFF shapes up for skin. From a shaping perspective my biggest concern right now is figuring out how to shape the nacelles. That can wait until I get the center panels skinned. I have some solid foam pieces that might work well and hot wire to get them to rough shape.

Once I have the remaining parts in hand, I'll be able to join the outer wing panels to the center panel then put the skin on. Fuselage in the aft section will be tricky too.
Hek-yeah! She's really shaping up nicely Kev! wing control surfaces look superb!

BTW I buy my "Y" harnesses - connectors on Ebay 3 for 3 or 4 buck$.
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Old Sep 15, 2014, 06:26 AM
ich bauen groß modell flugzeug
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Looking Great Kev!

K
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Old Sep 15, 2014, 06:47 AM
A Day @ a Time - Matt. 6:25-34
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North AL, USA
Joined Nov 2009
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Cheers gents, I will try to get her flying soon.
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Old Sep 26, 2014, 09:26 PM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
North AL, USA
Joined Nov 2009
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Power Tweaks

Well, I wasn't happy with the wattage I was getting on the GWS 8040 3 blade propeller, so I took the plunge and bought the 9040x3. I ran some testing on two 91% charged batteries. I got as much as 165 watts at a little over 14 amps, well under the rating of the motor (17) and ESC (22). Nominal sustained was around 145 watts at 80% throttle for several minutes so let's be conservative and make it 140 from each motor. I may try the tests again after I use a different charger - the one I used is very conservative with charging and I think it cuts off prematurely as a safety factor (a cheapie balance charger that came with an RTF model).
With an AUW of 61 ounces (minus covering but everything else), that translates into 70 watts per pound at four pounds even on the weight. It would be nice to have another 10 watts per pound (I still might get it) but I can live with 70. I have some slow flyers that fly great with this power. With the airfoil shape and wing cubic loading of 13.2, that is at the top end of scale but there are flaps on this baby so I can cheat a bit! I estimated earlier a max speed of about 42 mph, she won't scream around the sky like your airliners DD!
More to come once I get the batteries topped off properly.
Kevin
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Old Sep 26, 2014, 10:56 PM
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Quote:
Originally Posted by ruff1 View Post
Well, I wasn't happy with the wattage I was getting on the GWS 8040 3 blade propeller, so I took the plunge and bought the 9040x3. I ran some testing on two 91% charged batteries. I got as much as 165 watts at a little over 14 amps, well under the rating of the motor (17) and ESC (22). Nominal sustained was around 145 watts at 80% throttle for several minutes so let's be conservative and make it 140 from each motor. I may try the tests again after I use a different charger - the one I used is very conservative with charging and I think it cuts off prematurely as a safety factor (a cheapie balance charger that came with an RTF model).
With an AUW of 61 ounces (minus covering but everything else), that translates into 70 watts per pound at four pounds even on the weight. It would be nice to have another 10 watts per pound (I still might get it) but I can live with 70. I have some slow flyers that fly great with this power. With the airfoil shape and wing cubic loading of 13.2, that is at the top end of scale but there are flaps on this baby so I can cheat a bit! I estimated earlier a max speed of about 42 mph, she won't scream around the sky like your airliners DD!
More to come once I get the batteries topped off properly.
Kevin
Kevin . . .speed isn't everything lol. . . Having her fly is Priority number one here Sir.

A quality battery charger is a must. . Then do your voltage tests.

Your making excellent progress!
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Old Sep 27, 2014, 04:10 PM
A Day @ a Time - Matt. 6:25-34
ruff1's Avatar
North AL, USA
Joined Nov 2009
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Similar numbers with batteries fully charged and balanced. Battery run time comes out at a bit over 7 minutes with a 4400 mah 3S, but I think she'll cruise at 65-70% throttle. Amperage was at 24 at that level, so with that as an average draw that gives me around 9 minutes. I like to get to around 10 if I can. Those are numbers I can live with.
I have the y cables now so I can progress getting wiring in the wing finished and cover on the center section. Since the spar brace extends out the center section I can cover that first then work on the nacelles which will be a lot easier without the outer wing panels attached.
What is best practice to secure servo extender connectors? Shrink wrap? Cable tie?
Thanks!
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Old Sep 28, 2014, 06:52 AM
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Malanda, QLD Australia
Joined Jul 2004
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Hi Kevin, you've got something like 320W for take-off. That should be plenty!

I try not to put servo connectors where I can't reach them but if they have to be inaccessible I use shrink tube. That doesn't mean it's the best way but it works.

Rich
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