Acacia 3 F3F Build Thread - Post maiden bliss + report

[infopimp]

Follow me as I put together my Acacia 3 from F3X (F3X.com) and fly it!

This is the RG15mod version with 118 inch span - or JUST shy of 3m.

http://www.f3x.com/htdocs/acacia/acaciall3m.htm

Tom describes it on his site like this:

The wing chord is wider than the Acacia II and the span is 3m. This Acacia uses a modified Acacia II airfoil and was designed to be easier to fly than the aggressive Acacia II F3F. F3F models are generally "grippy" or "fast". The Acacia II is on the fast side the Acacia 3 is on the grippy side. In poor conditions the grippy models usually do better, in good air all models go well. So now you have a choice in the Acacia family.

I heard some mixed results about the X-Tail and think Tom said that the V-Tail is the only version available - mine is a White / Red V-tail.

Background: Tom had a sale on these and - loving the toughness of my A2 - figure it will give me something close but different than the A2... maybe better on marginal days or inland? I have the tube in there so kinda curious if I can make the wings flex a little. :) :) WE WILL SEE.




First, lets take a look at this plane and compare it to the beater-ized Acacia 2 that has served me so well thus far as my very forgiving F3F trainer.

My comments on the photos tell the rest.

[glderguy]

Nice job on the build Steve, you will like the plane although I feel the A3 will be more of the trainer while the A2 more the competition machine.
Walter

[infopimp]

Maybe I can avoid some repairs like you see then on the AII, then... for a while. :)

[infopimp]

Tonight I did the wing harness.

[infopimp]

Riveting thread, I can tell from all the chatter. :)

Maybe I need to open it up more to the peanut gallery: My question is in regards to the servoframes - will I be OK to just epoxy the frames to the CF patch I laid down, then screw in the servo? I figure there is enough surface area on the bottom to get a good "seat".... but wondering if I should also put a small bit of goop on the bottom of the servo when installing it.

[concreteman]

thats what I did on my last plane. Just a bit on the servo, too. WD

[blewis01]

Riveting thread, I can tell from all the chatter. :)


Mr Pimp, what is this tube you speak of .... as in "I have the tube in there so kinda curious if I can make the wings flex a little." Did Mr F3X install a "tube" and if so, is it in the wing ( you cut a hole in the wing )?

Bruce .... throwin Mr Pimp a bone as to "pump up" his build thread :)

[infopimp]

Bruce, yes, Tom pumped up my A3 with the big ballast tube mod before the fuse made its journey to NorCal.

I have a brass ballast set already with my AII and it is a perfect fit in the A3.

Next question for the lurkers - do you secure the wires of your wiring harness inside the wing? While I doubt they would interfere with the flap operation, my wires will current be able to flop around a little in there.

Oh... one more. For the brass part you connect the pushrod to on the (pre-drilled) aileron flap: ... what should I use on this? Black CA? 15 min Epoxy? Epoxy-microballons? JB Weld?

[dhauch]

Next question for the lurkers - do you secure the wires of your wiring harness inside the wing? While I doubt they would interfere with the flap operation, my wires will current be able to flop around a little in there.?

i always tack any loose wires with some hot glue to keep them from ever possibly getting into the servo linkage.
just cheap insurance. :)

dh
www.rc-builds.com

[blewis01]

Steve, what I don't get is why you cut the hole in the wing ( bottom left pic ). Pleeze splain a little bit.

Bruce

[infopimp]

Bruce: I need to get the servo wire from the body of the plane into the wing. Before I made this cut, there was no way for the servo wires to enter.

[blewis01]

Got it .... duh.... I was thinkin it had something to do with the big a55 ballast tube. Carry on.

Bruce

[slope soarer]

Hi guy's just bought new acacia 3 carbon version anybody else have one and could do with setup. :)

[infopimp]

Slope soarer - we may not be talking about example the same plane... there is an "A3 speed" in Europe which has a different foil.

Regardless, there are some good setup tips for the Acacia II on F3X.com for throws and so forth. FWIW, CG came marked at 97mm back from LE on my A3.

[chetosmachine]

I'm curious to know what the wing's panels weight :rolleyes:
It looks good; Hope you enjoy it!
Chets

[slope soarer]

The acacia 3 i bought is the 2.7m speed version i'am not intending to race it just for good windy days.So if anyone out there has one could you let me know how you get on with it. :)

[infopimp]

Slow incremental progress - tonight installed control horn into ailerons with layers of black CA slow cured. Extensions arrived.

Thinking of a blinged out CF servo tray, maybe over plywood. 5 cell 2600 pack is cycling.

[infopimp]

Chets - just saw your request for wingtip weights... doh! I should have weighed everything first. I have the servos mounts gooped in... and the servos are cling wrap and potted. Later I'll add more goop surgically around the edge of the servo frame.

[chetosmachine]

Hi,
even if all the gear is installed, i'm curious to know the weight of the different wing panels :cool:

Nice and clean linkages! At this rate, you will maiden it this weekend!

[infopimp]

Chetosmachine, flying her this weekend would be nice!

No problem on the weights:

Right Wing Tip = 360g
Left Wing Tip = 364g

These weights are after: removing servo box, laying down heavy CF mat as a servo mounting bed, gooping in servo frame, and adding the control post with black CA (these weights do not include servos or wiring).

Just tested the goop pretty well by pulling out the potted servos - after a little jiggling and quite a bit of "up" force.... they popped out. I'm convinced the servo frames aren't going anywhere after this exercise! Now the servos smoothly pop in and out and are mounting perfectly flush.

I will probably use the metal control horns - the 2-56 pushrod fits exactly into the pre-drilled holes (tight but fits with some work). Plus... they look cool, which is proven to make planes fly faster. :) There is literally zero slop in this setup right now, which is pleasing. Thinking of either doing a Z bend or doing an L bend and using heat shrink + CA to secure the pushrod from letting go.

[infopimp]

Below is the completed aileron install, the morning after. Just need to cut off the end of the metal control horn and should be close to done with the wing tips. Will bundle the extra servo wire with wax thread and heatshrink the extension/servo wire connector to keep it from pulling loose.


Next up are the flaps. Below you can see the control horn orientation - in the background are printouts of Tom's very helpful setup sheet (http://www.f3x.com/htdocs/howto/modelassy.htm) showing control horn orientations for various hinge/horn/access scenarios - what a great resource, thanks Tom.

These servo frames are the trick setup, I'm going to start using them on all my moldie wings going forward. I love being able to take the servos out, readjust horn position, etc... and then pop them back in. If I ever do bang up a servo I could do a field repair between runs.

Tonight I plan to make a jig (like in Tom's AII build thread (http://www.f3x.com/htdocs/howto/Acacia2build/index.htm)) for use in getting the flap control horns in the exact same spot on the top of the two flaps.

[F3X]

If that is the flap horn position in neutral I would move it 1 spline more forward. Small changes make a big difference in travel. I would also flip the servo so the arm is in the thicker part of the wing.

You can't Z bend through metal horns so you will need a clevis at the servo and grind away the inside arm to clear the output shaft to keep the servo horn length under the covers. using a metal clevis you get a metal to metal connection and may see some servo chatter from it or maybe not. I personally would use the plastic horns and get less slop but its your call!

[jgs99v]

Tom - What if Steve used the bicycle spoke end bent 90degrees threaded ends? Single ended - little slop etc.... Then he could keep his speedy horns - great for rutting :D. I did not know that metal to metal contact could cause chatter in the servo's?
Great work Steve - Now I'm considering servo frames - just looks kool. Not following the thread - but where did you get them?

[infopimp]

I would also flip the servo so the arm is in the thicker part of the wing.

Tom: Under the wiper there is a wood reinforcement placed such that it is ready to drill - but not if I move the control horn to the other side of the servo. Is this still advised?

I can get a photo later if this isn't clear. Thanks for the advice, everyone.

Frames are from http://www.servoframes.com - order form looks broken right now, but F3X.com and SoaringUSA.com also stock them. I'm ordering a bunch more right now.

[F3X]

Tom: Under the wiper there is a wood reinforcement placed such that it is ready to drill - but not if I move the control horn to the other side of the servo. Is this still advised?

I can get a photo later if this isn't clear. Thanks for the advice, everyone.

Snip

Not to flip the servo so the arm is closer to the fuse but flip the servo so the arm is closer to the spar (thicker wing section) and still away from the fuse.

[infopimp]

Ahhh... got it. I'll do that - I was working on the assumption that the shorter the control rod the better, and that having it closer to the TE would mean a more steep angle for me to cut through the TE spar... hence less material to remove.

[infopimp]

More progress. Tips are done.

The speed and torque of these servos is really impressive... almost frightning if you are used to 85MGs.

[infopimp]

I might move to the upper peg on the control horn - I'm only getting 20 degrees of "up" on the ailerons with EPAs/DRs pushed to 125%... I want to get closer to 25 degrees throw.

Trimmed the trailing part of the 'bump' on the servo cover back about 1mm to allow no-friction through full range of motion.

Onto the flaps and fuse.

[Wingtech]

The acacia 3 i bought is the 2.7m speed version i'am not intending to race it just for good windy days.So if anyone out there has one could you let me know how you get on with it.


I have one and love it had a moment of over exuberance on hols in France when VTPR went too TPR and broke the wing joiner but just a crack in the nose cone so very strong.

I love flying it it makes me look quite good sometimes and thermals like a goodun


Steve

See Here http://www.rcgroups.com/forums/showthread.php?t=693468

[jgs99v]

Wingtech - In your thread you mentioned 98.5 for CG - Is this your final?

[infopimp]

The A3 (RG15 3m) was marked 97mm back from the LE on my fuse... or that is where the ballast tube is CGed. Tom - is there a list of "official" CGs for the Acacias other than the A2?

Question 2: Is it advised to have the ballast tube CG slightly ahead or behind the unballasted plane CG?

Thanks everyone.


ps: i also had an overenthusiastic moment with my Acacia (II)... the inverted performance inspired me and I was doing a lot of cool moves... ending in a unique hammerhead stall that transitioned into a minor cartwheel in the tall grass.... (!!!!) The plane had minor skin damage (easily repaired that night) and I was AMAZED how tough the plane was to have otherwise held together.





back to the build... I'm off to work on the flap servos.

[infopimp]

Below see: relieved the wiper to make room and then the flap horn was screwed in to the pre-drilled hole... in these shots it is screwed all the way to the outer skin.

Would you agree I should trim the threaded down a bit so as to sink these in a bit lower?

Appreciate any feedback - hard to eyeball this without experience of what is right.

[Robbieuk]

Below, this is what Tom told me when i was building my A2 a few weeks ago....yes, the horns need to go way lower. You can see a close pic. of it on the A2 build on Tom's F3X site.
HTH.
Rob.

(For reference: Put the flap control horn hole just above the skin and the hole fwd of the hinge line by 3-4mm and you won't have any problems driving the flaps. Keep the linkage straight and position the servo arm about 35-40 deg to the LE for neutral.

Oh yea: trim away the balsa sub spar, on the newer versions you can leave the carbon caps if your horn is low enough but its more important to have both the same and tight.

Good luck!)

[infopimp]

Thanks - saved me another screw up. I'll use the plywood jig to mark a spot 3.5mm forward from subTE and maybe 1mm above the wingskin.


I just wanted to enthuse, again, over my aileron linkages - they are TIGHT! You can't move them at all - even 1/128th of an inch - by hand, even when the plane is "off".

Hope to get the same result on the flaps, no reason I shouldn't be able to do so.


Any suggestions on how to chip away at the subTE spar? I don't want to take away more than I need... maybe I should bore a pilot hole first.

[jgs99v]

Steve - If pre-drilled use a jewelers file. If not then predrill then slot.

[infopimp]

Shaved off 1mm from the base of the control horn - here is where I've got it set (see photo).... this is using the pre-drilled hole's angle... so it is snug in there. Peanut gallery have any feedback?

[checkenbach]

Steve, I think you need to shave the horn to have NO threads showing. Look at Tom's build threads again.
Chris

[jofo1]

on my latest builds the center of the hole in the horn is directly over the hingeline and even with the top skin, a bit shorter than you have currently, shorter horn provides more throw, allows you to use the shortest hole on the servo horn as well if getting under the cover is an issue. my .02

[infopimp]

Great - thanks for watching and continuing to chime in! I'll shorten them a bit more. I have looked at Tom's threads on F3X a million times now... his actually looks PRETTY close to what I have now, but I'll take off another 0.5-1mm of the threads.

I owe you all beers.

Here is the link to Tom's AII build again: http://www.f3x.com/htdocs/howto/Acacia2build/index.htm

Direct link to photo I'm using: http://www.f3x.com/htdocs/howto/Acacia2build/images/P1000150.jpg

-lather, rinse, repeat....

[infopimp]

Over the past week or so I've been tinkering on the flaps and finally got everything perfect. I'm really happy with the flaps! Had to use mechanical differential to get enough throw, but I'd say I have enough now! The covers fit and everything is really tight again. I see why you set the servos up like this - at full deflection they mechanically "lock out" a bit because of the angle of the pushrod at that point.



Other notes:

Used a dab of hot glue near the spar behind the flap servo to hold the long servo extensions in the middle wing section.

Wired the other half of the wing harness tonight. Getting better and faster at tinning / soldering / heat shrinking.

-

Question 1: do you think I have enough aileron throw? The image below shows full deflection at highest possible rates. Wondering if I need to move the aileron control rod to a different hole on the arm....

Question 2: anyone know what the stock VTail rods are threaded for? 2-56 is too big.

-

Thanks again for any feedback. I'm nearing the finish line - just need to make a servo tray now, then complete CG and setup.

Regarding the fuse servo tray... it seems that the best geometry for the Vtail servos will have them shimmed a bit more toward the front of the fuse, so the servo control arm angle goes down and matches the natural angle of the factory control rods.

[checkenbach]

I think the ailerons have more than enough travel, I don't think you'll use that much travel when you get the flaps and ailerons mixed together. The Euro threaded rod is 2mm I believe, I have some if needed. I maidened my Trinity last weekend, smooth, no surprises, flew like a bus compared to the Miraj(I had quite a bit of extra nose weight), and the winds were pretty light as well. Looks good so far!!!!
Chris

[infopimp]

Thanks, Chris!

I decided to reinforce the nose area - partially just for bling but mostly because this are appears a bit fragile on my AII (nothing structural, just cosmetic) and I can see through the seam lines in places on this A3.

I decided on the following layup from the bottom to the surface:

-two layers of thick woven CF (overlapping in the bottom/middle) on bias 45 degrees from each other
-and added a 3-4 12k strips of tow over the seam line and spiraling in the nose cose
-4 oz glass over it all.

Is all this overkill? Probably.

After laying everything down and blotting... stuffed the nose with a 2mil drop cloth and then carefully filled the nose cone and front of fuse with papertowels inside that, hoping for a smooth finish later.


In some of the photos below you can see how I have routed out the center of the VTail servo area, building a shelf for the plywood servo frame in the process. I have a 1/4" plywood tray and am slowly sanding it down to the perfect size. Will leave room for a thin CF laminate veneer if all works out. :)



Been setting up snap flap and such on the wing... can't say enough good things about the Airtronics servos at least so far on the bench they are unreal in speed and power, and return to center is dead nuts.

Ok, that's about it for tonight. I CANT WAIT TO FLY THIS!

[infopimp]

Pulled out the drop cloth and everything cured perfectly... made a plywood servo tray and slowly sanded it down so the servos fit snug.

Below you can see the servo tray, friction fit... from the side you can see both the pushrod angle I mentioned before, as well as the fact that the servo tray I made needs to be thinned down a bit. That is what is next... then add a plywood tray for battery and receiver in front.... then CG and finally ROCK AND ROLL TIME.

[checkenbach]

Why not use some screw in ball links and get the correct alignment to start with??????
Looks good so far. Chris

[blewis01]

.... then CG and finally ROCK AND ROLL TIME.

IP - Davenport next weekend?

Bruce

[glderguy]

Are those metal servo arms? If so was wondering why you chose to go metal? Just wondering.
Walter

[infopimp]

Walter - I guess... because I had them. They seem rock solid - some warn of glitching (?) with metal, eh?

More updates... the plywood tray got too thin and actually broke while I was gluing it in, so I stepped up to CF laminate.

[glderguy]

Build looks good Steve. Dont know anything about glitching/metal arms. Havent seen that many people use metal arms and was just wondering why you did, thought you may have caught on to something new there! When/where are you going to maiden?
Walter

[infopimp]

Been doing more testing.... I do notice a small bit of "chatter" in the servos once in a while... but these are digis, wondering if that is normal.... or if it is the metal horns.... or the Berg RX... (I noticed the red light goes on in the Berg when they twitch... which indicates a glitch).

Curious what the peanut gallery says about the metal horns - I can switch back to plastic in about 20 minutes if needed, but... should I? Try a different RX? I've seen eyebrows go up when I mention the Berg Full Range receivers to F3Fers... do they have a bad rap?


Once I figure that all out... I'll be ready to maiden... honestly could be ready this evening. This weekend is the last quiet weekend I'll have for a while so that looks like the time.

Place: Davenport would be nice... a friend says Banos is really good for maidens but thats a long drive and I've heard the lift can be spotty.

[glderguy]

Honestly, Im not sure exactly what level of unusual servo movement would distinguish
between chatter and glitching Steve. Many of my non PCM planes exhibit some servo chatter but have no issues in flight although once with a carbon kevlar weave fuse lay up I did have some obvious glitching as one of the flaps would briefly deploy now and then. I think you shouldnt have that issue with your fuse What Berg are you using? I usually only use Hitec or JR rxs but have a newer model seven channel Berg in my electric heli and so far its been rock solid.
Walter

[jgs99v]

Feedback - With the 9303 if the antenna is point at or near my servo's I get severe chattering. If pointed away this does not occur. This is only when the TX within a couple of feet or so??? My older Module7 aka Attracs does not exhibit this behaviour?
Is this something that Steve could be experiencing?
BTW: Kool building there!!!! So no shock absorber on the battery holding tray for the ice plant plant ;)

[infopimp]

Jack - that's it! It chatters when I am close and when the antennae points the same direction as the RX lead... I'll do a range check and see if this is an issue at all... thanks for the tip.

On the servo tray - actually there is a shock absorber - I used black CA (the semi-flexible stuff) to hopefully keep the tray in place on "arrival". Thanks for the reminder on the Iceplant... time to wax my new plane! :)

[infopimp]

It glitches big time when the antenna is inside the fuse - I experimented and that made it happen, every time... and it stopped every time removed.

I looked inside the fuse and there is tow reinforcing the full length, covering a big percentage of the fuse surface area.

I guess I could try another RX... or run the lead into the wings and add another connector... or maybe this lead got damaged during the build and I should try a new lead first... or...

[glderguy]

Mine, although Xtail, had the carbon reinforcement in tail as well. I ran the antenna,
Hitec SS, down the fuse with good results. Maybe its the Rx? As mentioned earlier, other than using the Berg 7P in my heli, with great results BTW, I have no experience w/it in sailplanes nor do I plan to gain any w/that Rx. Its not that difficult to return a crashed heli to new like condition, a molded sailplane is a different story.
Walter

[jofo1]

Just to confuse things, I've been coiling my antennas onto a 6" long piece of foam, taping it so the coils dont overlap, and stuffing it down the fuse a bit. My Victor has a good deal of carbon and my Supra has a carbon/kevlar weave (so alot of carbon). I've spec'd the Supra a dozen times, no problema. I've had zero glitches when range checking when I remove my TX antenna, which is a ducky. JR790 rx.

[Doc Holiday48]

It glitches big time when the antenna is inside the fuse - I experimented and that made it happen, every time... and it stopped every time removed.

I looked inside the fuse and there is tow reinforcing the full length, covering a big percentage of the fuse surface area.

I guess I could try another RX... or run the lead into the wings and add another connector... or maybe this lead got damaged during the build and I should try a new lead first... or...

I use a Hitec RX in one of my Acacia's and a Futaba in the other and run the antenna all the way down the fuse, without any problem at all. Although I do not have the carbon reinforcement in the nose that you have added. Not sure if that would make a difference. It might be your Berg, I have never used one of those. I have never heard of anyone flying Acacia that have had a problem with the antenna in the fuse.

Bob

[infopimp]

I've lost all faith in the Berg7 for now in this plane. Switched to a HiTec receiver and now all is well. Tonight I "cast" the nose weight (5 oz+ was needed) and am finishing settings.

[infopimp]

CG is at the point indicated 97m. The chord at center root is ~238 mm giving ~40% - seems about right.

-

I did most of the nose weight with ballast and epoxy shot, my "method" is shown below. The remaining 1.5 oz is being done with 1/4 removables for fine tuning if needed.

-

I moved to the Hitec HPD-07RH 7-Channel QPCM Receiver. This receiver is really good with handling the radio being shut off - I have the "Fail" mode off and it just holds the exact position when power is lost, no problem. The Berg would twitch into a spaz... (I hadn't programmed the fail mode... but...)

More importantly - this receiver doesn't jitter like the Berg - see the video below for a small sampling (uploading). This happened whenever less than 6" of the receiver antenna is outside the fuse.

I'll send it in and find out, maybe its just me. Maybe its the CF I added?? :)

-

Lessons learned so far: next time, consider single or at least smaller wing connectors or... smaller heat shrink overall - my setup now takes a couple minutes of plane yoga to make it work. The BIG ballast tube is in there... so my long connectors are a tight fit and I'm worried about binding with the tail pushrods in theory (but not seen in practice).

-

I've been doing a long run today on the batteries - running the servos to make sure it holds up for a bit... then will top it off and get a feel for drain. The digis and 5-cell 2600 AA pack will have enough for a couple hours of flying....

[infopimp]

Here is a video demonstrating how the Berg responds to having the antenna inside the fuse... best shot showing the behavior is right at the end. All 6 servos were chattering.


The noise shown here was persistent - when I moved the controls it would amplify the intensity of the spazzing and also get erratic.


Right-click and download (mac: option-click...)
http://www.imageseek.com/TMC/berg7_twitch.mov

-

The Hitec receiver has the Airtronics completely quiet at rest... it seems more FAST/precise too than the Berg7 does in my AII. I am using the QPCM mode instead of PPM.

Moving on for setup: I just enabled the fail mode - this is a fail setting that only works with the Eclipse and this specific receiver (HPD-07RH). The fail mode - in my testing - engaged within 1 second to the TX being turned off... and disabled 2 seconds when turned back on.

My "fail" setting of choice so far is a very light crow (flaps down 5 degrees, elevator down a hair per my settings) - no rudder or aileron... I figure this would be a safe indicator and also better than full flaps if I really ever lost control for some reason.


-


My AUW is 92.5 ounces. Stout.

[chetosmachine]

Sooooo, how did it go!?!
Any maiden report + picts?
Any report? Any pict? Any...thing? :p
Chets

[MarcusT]

F3F race next Sunday at the Slot . . . bring her out Steve . . . I'll have a new version of an 'oldie" out there to maiden also.

Mark Triebes

[infopimp]

BEST maiden I've ever had with any plane! My confidence in the build helped my confidence on the sticks. She gave a flawless performance... no video of the maiden was shot so here is the quick summary of how it went at Davenport today:

-15-20mph NNW (pretty heavy North component, even for Davenport) - warm (T-Shirt weather)... just enough wind that the sand wasn't yet kicking over the edge. TONS of kite surfers down below.

-BruceL launched the plane for me... no elevator trim was needed, 4 clicks of right - in retrospect glad I had the low rates per Dom - it was a bit twitchy.... even the low elevator rates were still high, dialed them down in real-time about 10% (now im at 50% low, 60% high... I'll post all settings in degrees once I'm finished with most of the "Tuning")

-FWIW, I am using only -5 expo (I've been weaning myself off expo and don't regret it)

-using Tom's setup sheet for AII throws, settings were perfect! I was using about 2mm of snapflap - wasn't scrubbing speed in turns... surely I'll do a bit more tinkering with this part of the setup but everything was well behaved

-responded VERY well to camber - was able to turn on a wingtip (see below)

-dive test showed very slight tucking

-it does seem less squirrelly than the AII, but NOT boring/floaty

Had a fun and heart pounding flight. 10 minutes after launching, Bruce announces that the first of three full-size planes were taxing to prepare to take off using the landing strip that IS Davenport... so I dialed in about 1.5mm of camber and started circling up over and a little behind us... it would just hang in place above us... then when I took the camber out, she MOVED! Reflex, she moved even more. Thanks to Bruce for spotting for me and helping me stay out of the way

-Surprisingly (counter to what I've read about most planes) when I added camber, the plane required some up elevator... reflex required some down elevator - I will add those mixes.

-I had WAY more than enough flap! I never got more than 70 degrees before the plane was literally hanging like a kite - I think I could hand catch this plane in time. Adjusted the elevator comp for crow while flying and it is now perfect!


-I started getting a little more aggresive toward the end, and it started making "that sound" (though faint) when flying by... no ballast today but I could have used a few slugs.

-Started practicing some "Kyle-style" turns - was getting some of that roller coaster momentum going... can't wait to continue to refine the line.

-Landing was VERY technical today - several of others' beautiful planes were "rekitted" today but I brought the A3 down and - despite the same problem everyone else had (too much lift in landing zone... + rotor) - I brought it down actually on the runway at a walking pace... not even a scratch on the bottom!

I decided to count my blessings (especially after watching the re-kitting of some other beautiful ships) and took her back home in one piece.



Mark: I'm VERY excited to race this but I will be out of town that day. Trust me, I'll be F3Fing this plane very soon.

Having picked up this plane on sale from Tom for $900 - and with his 6 digi servos combo at the time adding $300 or so... I think this was a great value and am VERY psyched to wring her out.

Thanks to all for watching this thread and listening to my ramblings... now to get some more F3F races under my belt!

-steve

[glderguy]

Congrats on your maiden Steve, nice looking plane you have there!
Walter

[Kai@UCSB]

Steve,

Nice job on this plane!!!

-Kai

[infopimp]

Thanks guys - loaded her up to 8 of the 9 big slugs today at Davenport and it was really breathtaking. I mean... it looked like the 'real deal' running the MoM course. I'm jazzed! Three more flights, three more landings (including 2 just perfect)... all still in one piece!

[F3X]

Thanks guys - loaded her up to 8 of the 9 big slugs today at Davenport and it was really breathtaking. I mean... it looked like the 'real deal' running the MoM course. I'm jazzed! Three more flights, three more landings (including 2 just perfect)... all still in one piece!

1-piece is awlays good!

Keep up the good work!

[jgs99v]

Steve - Great you were able to get out for both days! I was soo close but no chance!!! Glad you got to fully load it up!!! Great job - and patience pays off in the end. Battery indicator led panel - is my next item to buy!

[infopimp]

Me too - I've heard some folks don't trust the 2600 AA packs (internal resistance?) but mine seem good so far. Drained 500 mah over about 45-60 minutes of airtime.

[jgs99v]

Steve - Tom and I discussed this and I've considered ohm's law - In effect I'm experimenting with his 200mAH 4 cell pack - I flew roughly 50mins total - three flights with 6 digitals and upon recharging it indicated 384mAH. So time will tell as I track this.

[chetosmachine]

Glad to hear your maiden was great!
I run 2500 AA ni-mh on my f3f/b plane. No problem since the plane was assembled, in april of this year. Flight time so far has been 15 hours; the max continue time i have flown was 80 minutes and i stopped because i was tired!
My 6 servos, hs-85's stile, draw around 700 mah/hour (don't know how much MPG does this translate into :p ).
I have had no issues on winch launch, which put great stress on wing servos, nor on full crow when going fast.
On other sloper, i have 4 ni.cd 4/5A 1600 mah, and they work great too.

The main difference between both, is that the 4/5 A type cells accept 1c charge, while my AA don't. If i try to charge at more than 1A, they will false peak the charger. So i usually have to remember to charge the big plane before going to fly.

Chets

[infopimp]

Yeah... I charge my AAs at C/3 and leave a trickle charge just to be sure because of the false peaks. The temperature monitor helped my ICE find the peak as well...

I had just heard some folks say that the AAs could be strained by 6 digi servos working hard - possibly dropping the voltage below required levels to keep the receiver from moving into Fail mode. So its less a mah issue than an "ohms" issue... sounds like I'm still in the clear however.

[F3X]

Yeah... I charge my AAs at C/3 and leave a trickle charge just to be sure because of the false peaks. The temperature monitor helped my ICE find the peak as well...

I had just heard some folks say that the AAs could be strained by 6 digi servos working hard - possibly dropping the voltage below required levels to keep the receiver from moving into Fail mode. So its less a mah issue than an "ohms" issue... sounds like I'm still in the clear however.

So far I have had no trouble with the 2600, they are finicky when charging but once you get the correct rate they are fine. A full day of racing at Davenport usually takes about 375-425 to fully recharge, That's about a hour of racing or sport flying.

The cells John are using are GP2000 4/5 A and a high rate cell so they will have the current available and are about the same cost. But I never experienced any receiver fail safe or low voltage when racing, F3B launching or F3F racing the 4 cell 2600 packs either. Maybe the DS guys have some input?

[ouluckydogu]

Info

What servos didi you use in the wing and where did you get the mounts for them?
Lucky

[infopimp]

Lucky - its all in this thread ( :) ), but I used Airtronics thin wing digis and frames were from http://www.servoframes.com

[djklein21]

So far I have had no trouble with the 2600, they are finicky when charging but once you get the correct rate they are fine. A full day of racing at Davenport usually takes about 375-425 to fully recharge, That's about a hour of racing or sport flying.

The cells John are using are GP2000 4/5 A and a high rate cell so they will have the current available and are about the same cost. But I never experienced any receiver fail safe or low voltage when racing, F3B launching or F3F racing the 4 cell 2600 packs either. Maybe the DS guys have some input?

I have heard the horror stories about high internal resistance nickle metal cells from some fliers. I think this was a valid concern in the days when Nimh cells sucked. This just isn't the case anymore with any decent cell. I use sanyo 2500 mamp AA cells in all of my planes that will fit them. If not I use some Ib 1400 Nimh cells. I get all of my battery packs from Steve Belkknap at Diversity Model Aircraft (flydma.com). He builds really nice custom packs that I trust all of my planes to. I learn well from others mistakes and have never lost a plane to a battery issue. I always use a charger that tells me what it took out on the discharge cycle and what it put in on the charge cycle. I always cycle a new pack three times before I fly it. I havent had any issues with the 2500 or the 1400 mamp cells false peaking, but I have had to work at getting some of my larger cells(9500 mamp) to condition and not false peak.

[infopimp]

What charge rate do you use on your AA cells? C/10? C/5?

[glderguy]

Hi Steve. Im not sure I quite understood your ? Did you mean should you charge at a rate of 10C/5C? If so is that a little high?
Walter

[jgs99v]

David - The battery that was in the Nxy; 2700mAh Ni-MH/.5A Chg
Does this mean that you can charge at a rate of 500mA? Yep it has the FlyDMA.com label on it.

[tewatson]

C/5 = 1/5 of C, and so on.

Tom

Did you mean should you charge at a rate of 10C/5C?

[infopimp]

Some further updates and musings on the A3 to "follow through".

I now have 10 exciting flights.... and 10 feather touch landings... never have had to use more than 65 degrees of flap.

The A3 is exactly as Tom describes it on his site. I'd say it is slightly more forgiving that the Acacia 2 - it gives me another millisecond or two to react.

I do think it is banging turns in light condition a bit more quickly than my AII does... doesn't seem to need as "round" of a turn in those conditions... that is a totally subjective observation ... who knows, could be just my CG/setup diffs.

The skins are fragile - I got some minor road rash somehow and see small dents in the surface of the wing.

-

I ballasted it up at Davenport the other day to 3 slugs and it was starting to HAUL. 6 more slugs are available.... tempting. But.. I am taking it easy. Noticed that landings in crosswind conditions were much easier with ballast... seeing fewer and fewer reasons not to fly with a few slugs in most of the time - at our nice spots.

AUW is 92.5... I'm flying around 110oz with three slugs in... can get up to 145 right now with my brass ballast. The wing surface area is not published so I can only guess at loadings -

Tom any idea on that?


-

More setup nuances (bear in mind I'm no seasoned vet):

I could see it accelerating nicely in the downwind turns - my snapflap is about 6mm so far at full elevator. Loves the inverted flight like the AII... so the split-S turn style is easy... is that the right name for when you rotate upside down and give up elevator?

When I screw around in thermals.... I'm running about 3mm max camber and 2mm max reflex so far... the camber mode is pretty effective. Reflex is really effective to get it moving... RG15 likes reflex I've read.

I have a launch preset with TE drooped 5 degrees (with light elevator comp) and it just climbs up and out, hands free - can't wait to try it at F3F.


-

One last musing...

After flying at Davenport, I remarked how the big planes like this - on epic spots/days... really get my heart going. It is a huge rush when it lands in one piece and you can "lock in" that whole experience in and get ready for the next flight.

Thanks to everyone for watching and helping this along. Now time to race. Cheers, -steve

[Doc Holiday48]

Hi Steve,
Here is an Excel sheet on the wing loading info that I used for my A III. I have the file at home with the calculations already done. I will try to find the file and post it for you.

Bob

OOPs sorry it would not accept and excel file. PM me and I will try to email it to you.

Bob

[glderguy]

Sounds like you are getting your new plane dialed in Steve, glad you are liking it. Its a glass wing so it will get a few dings etc on landing, even in the ice plant. Not much you can do about that. Ive flown the xtail at around 11lbs and found it very well behaved at that weight as well, if conditions allow dont be afraid to ballast it up. Are you going to race in nexts years ISR
MOM race?
Walter

[infopimp]

Bob - a tip: you can change your Excel file extension from .xls to .zip (or better yet, actually ZIP it) and then you can upload it as an attachment. PM sent regardless, thanks.

Walter: You know, I would feel too bad at this point in my "career" if I ended up taking out someone elses plane at MoM - less my own. I'll get there. Give me a dozen F3F races first.

I see Davenport ISR MoM as the holy grail of slope racing... before you seek the holy grail, you must answer these questions:

1. Are you a good enough pilot that 2 other guys won't be scared to fly with you in your heat?

2. Are you able to financially and emotionally support the loss (potentially) of a beautiful 3m ship - and possibly that of a flying buddies - and have dozens if not hundreds watch the video replay here on the forum afterward... ("Yah... it was definitely Steve turning into Walter's plane, look at frame 545")

And the last most important question you must be able to answer....

3. WHAT is your favorite color?

-steve

/Blue. No yel-- Auuuuuuuugh................

[glderguy]

Ive seen you fly Steve, you are plenty good enough to fly ISR/MOM.
Walter

[blewis01]

Ive seen you fly Steve, you are plenty good enough to fly ISR/MOM.
Walter


Yes, but is he rich enough?

Bruce

[infopimp]

My buddy Robert captured some video of the Acacia 3 in this movie, check it out - its the white plane near 3:20

http://www.rcgroups.com/forums/showthread.php?t=746086

No ballast - wait till you see it fully 'laden'

bruce: like i said i got my money tied up in lotto but there is a drawing next week...