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Old Mar 27, 2012, 09:34 PM
KK4EHM--FPV Mon!
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United States, FL, Sebastian
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Originally Posted by jglover View Post
i did mean ESC.. haha.. too many acronyms in one day. How do I go about testing it with the watt meter?
The watt meter connects in between the battery and the esc, when you throttle up you read the reading on the watt meter.
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Old Mar 28, 2012, 11:18 AM
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Originally Posted by jglover View Post
Ok, so since Ive been asked, here is how I did the t-tail mod step by step. Keep in mind, I have NOT done a Maiden Flight yet. Im waiting for a 3S Battery to come in from HK so I dont burn up my motor. Anyways, here goes...

Step one:
Cutting the vertical stab to be flush.

If you notice when it comes in, the bottom of it is curved to fit on top of the tail wing.Do not shorten the length, just make the front bottom of the stab flush with the rest of the bottom (see Pic 1). Next is to make a "canal" that the Vertical stab will sit in. I used the tail wing supports to do this. Seperate the supports far enough apart to fit the Vertical Stab into. I lengthend mine to place a servo in it as well. I used balsa wood to run in between the supports. DO NOT Glue yet. This is only to get measurements and make sure it fits and is what you want. I moved the rear support foward approximately an inch to have the end of the rudder flush with the CF Rod.(See Pics 2,3,4 and 5).

Step 2:
Attaching the Horizontal Stab to the Vertical Stab

1st, find the center of the Horizontal Stab (the wing with elevator). From the factory, my line that was present from having glued the wing together, was not exactly center, so measure it and use the Tip of the "V" as a center line for the front. Once you have determined the center line, place the vertical stab onto the center of the horizintal stab and draw a line around it. (See Pic 6, 7 and 8).

Now that you have drawn the lines around the vertical stab, now its time to get that Soldering Iron out and heated up with a cutting tip. MAKE SURE that when you cut this out, that the Horizontal stab is level. You will cut into the Horizontal stab creating an angle that his high on the pointed side of the wing and going downward into the foam and completely through the foam towards the end. DO NOT CUT past the bend for the Elevator. You want that to be one piece This angle is because when you cut the bottom of the stab flush, it made the top of the stab angled downward. If you did not angle the cut, your horizontal stab would be sitting at that same angle and you will have problems. (See Pics 9-14).

Next, I took a piece of the CF strip that came with the plane and cut a strip to fit the vertical stab. I then used an exacto knife and ruler to cut a slit into the stab to insert the CF strip. This is to add support to the stab. DO NOT cut the slit all the way through, just deep enough to insert the strip (See Pic 15).

The next step is to cut away the excess of the support used to make the canal (See Pic 16 and 17). Now assemble everything to make sure it fits together all nice and snug and DO NOT GLUE ANYTHING YET! Notice how in Pic 18, the Horizontal stab is level on the vertical stab because of the angle that was cut. Make sure this is right.

Now, its time to start putting it all together. Using 5 Minute Epoxy mix (Get 3 tubes) epoxy the "canal" together, but DO NOT epoxy it to the CF Rod yet. When I made my Canal, I added three Jumbo Craft Sticks (from Wal-Mart) to wedge the vertical stab into place (sides and bottom). Make sure it is tight. This will add to the support of the wing. Epoxy the Vertical and Horizontal Stabs together as well but DO NOT glue it into the canal yet. (See Pics 18-24).

Next, I took a Jumbo Craft Stick and glued to the bottom side of the elevator. I did this to add leverage and support to the elevator for when I mount the servo to pull on it. This allows even movement between the left and right side of the elevator instead of pulling up the center only, or one side or the other.
I also mounted a Jombo Craft stick on both sides of the vertical stab to add support. All of the sticks were put on using the epoxy. (See Pics 25 and 26)

Now, its time to make the Supports for the T-Tail. Using the Jumbo Craft Sticks and the other part of the wing support (skinny piece of cut out wood with three slots.. there's 2 of them) supplied in the package, I made the support. Cut the round ends of the craft sticks flat. Now, cut each slot from the skinny piece of wood evenly and cut the round ends off. (See Pics 27 and 28) Epoxy the pieces together at about a 45 degree angle as shown in the pic. Let them dry.

Now that you have the supports made, its time to attach them.. You will need a level surface and a small bubble level. Now, look back at your assembled tail section and look at the top. The excess sticking out of the top needs to be cut off so the top is flush. (Refer to Pic 21). After you have cut that off, now turn it over and lay it flat on t your level surface with the vertical stab sticking up in the air.. Make SURE your surface is level. This is key to this step. Now, grab one of those Jumbo Craft Sticks from that big bag you got and lay it across the Vertical stab (See Pic 29). Place the small bubble level on top of the Craft Stick. Push or pull the vertical stab left or right to make it level. ****NOTE: if your surface is not level, then your tail will not be**** Here's the complicated part. After you have figured out about where you need the Stab to be, let it go and grab your two supports you just made with the 45 degree ends. Place one on each side so it looks like Pic 29. Epoxy only one end of each support to the VERTICAL STAB ONLY. Let it dry. After they have dried, now take the other ends and move them along the Horizontal stab left to right as viewed in Pic 28 until your bubble is in the center of your level. Mark the ends and epoxy them downin that position. ***NOTE: You will have to hold the supports in place by hand while they dry. If you dont, they will move and dry in the wrong position*** Your done with that step.

Now, Its time to epoxy the T-Tail into the Canal. Put a nice layer of epoxy into the bottom and along the sides of the canal. Now place the tail into it, wedging it in. Fill in all the gaps with epoxy, especially around the front of the stab where it "V's" to the front. If you plan on putting a servo in front like I did, put a block up in front of the "V" so that the entire gap is not filled, leaving room for the servo. You can kind of see what Im talking about in Pic 30. Notice in Pic 31 that the Jumbo Craft sticks I put on both sides of the vertical stab are going down into the canal. You want this to happen! It adds support. Be SURE to epoxy arond them really good and get it down into the canal all the way around the Stab. Now, let it dry.

Now, once you have the whole thing together, you can now slide the T-Tail onto the CF Rod. DO NOT GLUE IT YET! Place your wing onto your fuselage and your fuselage on a level surface. Grab that little bubble level and place it on top of your main wing. Make it level. Now, keeping the fuselage and wing together and level, twist your T-Tail to make it level too. Check it with the bubble level and re-check the main and back again to the T-tail. Once it is all in line, epoxy the T-Tail to the CF Boom. DO NOT bump the tail out of place. Let it Dry.

Now, You are almost done. The only thing left is to mount the servos. I played with several different ways to mount them and found the best to be the following. The Rudder Servo is mounted directly in front of the Vertical Stab inside the canal. I took a Jumbo Craft stick and cut it up to fill in the void around the servo until it became wedged in. I then epoxied it in, but only around the craft sticks. I filled the rest of the void with silicone; filling in the entire remaining openings of the canal. (See Pics 30 and 33). Now, you will need to mount the Elevator Servo. You will need your Soldering Iron again for this one. Place the Servo on the center of the top of the T-Tail and mark an outline around it. You want it to face so that the servo gear thats sticking out of the top of the servo is to the opposite side from center as your control horn. That way, when you put the Servo arm on, its flush with the Control horn. OR, you can mount the servo and then mount the control horn.. Its up to you. Now, Epoxy that servo into place. See Pic 35 and 36. Any ways, my findings were that if you mount the servos on the CF Boom, there is not enough movement of travel in the rudder or elevator to cause the plane to respond while in flight. This is because the servo wire bends because of its length and the angle they are pusing. Moving the servos to the places I stated, allowed full range of motion for the elevator and rudder because the wires are too short to bend and they remain stiff.

AND THERE YOU HAVE IT! T-TAIL MOD STEP BY STEP. If you have any questions, please feel free to PM me or quote this posting and I will be happy to respond. I am also open for critiques on the design. Thanks and I hope this helps you guys out and takes the guessing out of making the t-tail.
nicely done ,waiting for maiden video ,
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Old Mar 28, 2012, 04:36 PM
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Australia, VIC, Metung
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Nice work jglover! 1. On the tail mod and 2. On the step by step.

Am I right in saying the only thing you have connecting the tail to the boom is the foam with balsa sheeting on each side?
And does the point of contact at the top of the vertical stab stop at the rudder hinge?

The one things I did different with mine was to run 3x3mm CF rods through the inside of the vertical stab and right down through the tail boom. One CF of the rods goes right through everything. Even after all this, it is still the 'weak point' of my rig.

It drives me nuts the amount of times I've caught the tail on my car door or banged it on something walking through the house, in some cases twisting it and pushing the elevator servo up. So it not only has to be strong in flight, but even stronger when it's in my clumsy hands!


Good luck with the maiden.

So far around 12 flights on mine and not a problem.
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Last edited by wingsnapa; Mar 28, 2012 at 05:01 PM.
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Old Mar 28, 2012, 07:19 PM
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I did fail to mention that you need to cut the rudder to free it to operate properly. This is the pic. As far as my attachment points, I just epoxied the around the front, sides and untereath and filled in any gaps that were in the "canal". I did put a piece of cardboard that acted as a stop in front of the Vertical fin to keep the epoxy held back so that it did not run into where I wanted to put the servo. The Horixontal Stab and vertical stab are epoxied from the front all the way to the back, including the rudder. you will cut the rudder free afterwards. Ive hit this thing more than a few times already and its still solid as a rock. Oh, and while we're on the subject, when you go to test all of your electronics and Transmitter for the plane, make sure you have all your wires tucked inside the fuselage. I had my batter and receiver hanging out the side when I did my test. I hit a switch that I thought was totally unrelated to the throttle and she went wide open and cut my battery wire and all my servo wires. Needless to say, lesson learned.
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Old Mar 29, 2012, 10:56 PM
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United States, FL, Daytona Beach
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Heres a question for the Gurus.. Is it possible to run the entire FPV System and plane off of one battery? I noticed when I hooked up my OSD that it was giving me MaH used, but by the battery that was running the OSD, not the battery that the motor was running off of. I did have the main batter hooked up to the current sensor and all that did was make the voltage indicator go up to the 14.7v for the 4S. Or, am I just assuming things and the MaH is the combination of the two. It only displays one MaH consumed.
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Old Mar 30, 2012, 06:56 AM
Team Basement-RC
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Canada, ON, Toronto
Joined Jan 2011
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Depends on your OSD. The dragon OSD has two voltage indicators. One for each. However, lots of people run everything off of one battery. There are pros and cons for both setups, but it can definitely be done.
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Old Mar 30, 2012, 07:38 PM
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Well, I atempted the Maiden Flight today.. Seemed like everything was wrong. She got up and immediately did a hard right that I couldnt pull it out of, and hit the ground. Couple scars but no major damage. So, I tried again. Launched and the tail dropped significantly. I gave her some down elevator to level her out. That went fine. Went to turn left, got no response. Turned right and she was extremely responsive on the right turn.. well, too responsive. Since she wont turn left, I couldnt stabilize her from the right turn. Bam! another crash, but no major damage to the plane but lost the landing gear and a few more scars. Tried flying again to try to confirm that she was tail heavy and wouldnt turn left. Well, I got a little softer landings (crashes). Other than that, not a great maiden at all.. She still drags her tail pretty bad in the turns that I was able to actually do, but there again, I didnt have the rudder mixed in either. Im guessing Im going to need to upgrade to a larger servo to get more movement on the ailerons, but Im stumped as to why she would turn right and not left. Anyways, Im doctoring her up now and hopefully Ill get her back in the air tomorrow. I will say this, that T-Tail mod DEFINATELY saved my tail section today.
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Old Mar 31, 2012, 03:38 AM
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Got her all back together and hopefully worked out the kinks. Switched from the generic2.4 Ghz Radio to the 72 Mhz Futaba and maxed out the end points of the ailerons. The seem to have more up and down now, so Im hoping this fixes the turning problem. And for those of you thinking it may have been a servo issue, I checked them and they were working, so I dont know. There wasnt much of the left aileron pushing upward when I ground tested it after the flight. I thought it'd be enough because the right was the same way, but here goes the trial and error. Still got to mix the rudder, so Ill be figuring out how to do that on the Futaba tomorrow before I giver her another flight. Correct me in saying that most everyone is adding 10% rudder with the ailerons? Anyways, wish me luck that tomorrows flight is 100 times better than todays.
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Old Mar 31, 2012, 04:43 AM
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Originally Posted by jglover View Post
Got her all back together and hopefully worked out the kinks. Switched from the generic2.4 Ghz Radio to the 72 Mhz Futaba and maxed out the end points of the ailerons. The seem to have more up and down now, so Im hoping this fixes the turning problem. And for those of you thinking it may have been a servo issue, I checked them and they were working, so I dont know. There wasnt much of the left aileron pushing upward when I ground tested it after the flight. I thought it'd be enough because the right was the same way, but here goes the trial and error. Still got to mix the rudder, so Ill be figuring out how to do that on the Futaba tomorrow before I giver her another flight. Correct me in saying that most everyone is adding 10% rudder with the ailerons? Anyways, wish me luck that tomorrows flight is 100 times better than todays.
Man sorry to hear about that. Mine actually went in too when I bent over to pick up my sunglasses thereby blocking the signal to the RX with the side of my car

The only thing not damaged was the T-tail. But mostly foam damge..all electrics, osd, video and servos fine.

I have 125% (max) rudder to aileron input, so the rudder moves more than the ailerons. Mine seems to turn smoother on rudder than aileron. I also have about 1/2 inch of dihedral at the wing tip for inherant stability, so I think this plays a part.

The tail tends to hang on turns because there is essentially no side profile on this bird at the rear and heaps at the front.

I added a balsa triangle forward of the vertical stab to increase its surface area and give her a more substantial profile in turns. Seems to kinda work, but really unsure at this point as it may need to be bigger and extend further toward the prop.

I recently separated flaps and aileron servos (4 on the wing now) so my ailerons are only about 6inches wide out at each tip.

She needs more work IMO but flys quite well and stable but nothing like the stock bird..lol!

Oh and don't forget to check your CG, it seems to fly better forward of the recommended point than behind. This thing is almost impossible to fly tail heavy. The golden rule is Nose Heavy=comes in hot, Tail Heavy=comes in NOT!

One of the downsides of EPP is that she pretty much needs to be re-trimmed every second flight.
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Old Mar 31, 2012, 01:24 PM
UAV Dude KF7HYV
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Originally Posted by jglover View Post
Well, I atempted the Maiden Flight today.. Seemed like everything was wrong. She got up and immediately did a hard right that I couldnt pull it out of, and hit the ground. Couple scars but no major damage. So, I tried again. Launched and the tail dropped significantly. I gave her some down elevator to level her out. That went fine. Went to turn left, got no response. Turned right and she was extremely responsive on the right turn.. well, too responsive. Since she wont turn left, I couldnt stabilize her from the right turn. Bam! another crash, but no major damage to the plane but lost the landing gear and a few more scars. Tried flying again to try to confirm that she was tail heavy and wouldnt turn left. Well, I got a little softer landings (crashes). Other than that, not a great maiden at all.. She still drags her tail pretty bad in the turns that I was able to actually do, but there again, I didnt have the rudder mixed in either. Im guessing Im going to need to upgrade to a larger servo to get more movement on the ailerons, but Im stumped as to why she would turn right and not left. Anyways, Im doctoring her up now and hopefully Ill get her back in the air tomorrow. I will say this, that T-Tail mod DEFINATELY saved my tail section today.
When standing behind the aircraft does your prop turn counter-clockwise?
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Old Mar 31, 2012, 01:32 PM
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jglover ...... what servos are you using? ..... you certainly need decent servos on this bird (IMHO) .......

I also mixed rudder with ailerons ...... can't check the number right now ..... Tx not with me ........

I also had to add some left motor thrust if I rem correctly ....... I did post the info earlier on the thread .....

finally, I put a small amount of 'up elevator ' on a Tx switch, just for take-off ....... I switch it off once I'm up and away ..... takes the pressure off you if your doing the throw yourself .....
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Old Mar 31, 2012, 01:56 PM
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johnorama, the prop is spinning correctly with all the thrust going back. She'll scoot on the ground for sure.

Hobbie14, I have the Hextronic 9 gram servos. Im contemplating on upgrading to the 15 gram servos though. I did however figure out what the major problem was.. 16 oz of lead later in the very tip of the nose, shes ballanced. Thats with the battery as far foward as she goes and the only thing under the wing now is the receiver (for now). I guess thats going to be a down fall to that t-tail mod. It added more weight than I thought it would. Im also going to adjust my servo linkages to give me 60/40 up/down on the ailerons "because it's a flat bottom wing". This was suggested by my go to guy at the hobby shop. Guess my saw horse CG idea didnt work out too well. I bought the Great Plains CG machine and now Im pretty comfortable with putting her back in the air. Im not sure what the weight limit is on this bird, but she's definately getting heavy. I'll have to go weigh it again. Im hoping all this will correct the problem. She's got enough battle scars from the Maiden and I dont want to add any more lol
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Old Mar 31, 2012, 02:06 PM
UAV Dude KF7HYV
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Which way does it rotate? It sounds like your cg might be too far aft which makes it easy to stall and roll opposite the prop rotation.
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Old Mar 31, 2012, 04:04 PM
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ALLLL SMILES NOW! IT FLIES!!! Added 50% rudder with the ailerons and turns pretty good. May bump the rudder mix up about 15% more. Its gonna take some getting use to; thats for sure. Shes got to scoot to stay up though. My only gripe is that she's coming in way too hot on the landings. Had a couple hard landings, but she stayed upright and on the tires. It was kind of butt clinching though. Anyways, the plan now is to put flaps on it to hopefully slow her down on the landings. Would this be another stab to add, or can I somehow mix the existing ailerons to both go down at the flip of a switch? or would this be a bad idea?
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Old Mar 31, 2012, 04:17 PM
UAV Dude KF7HYV
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I think you're the first person to complain that it flys too fast. This airplane is a slow pig as it should be.
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