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Author Topic: Heron (Multiplex) assembly  (Read 9308 times)
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Konrad
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« Reply #25 on: August 12, 2016, 08:40:07 PM »

...
I'm waiting to see your maiden flight.

All the best.
John
Thanks, I hope it doesn't mimic a lawn dart!
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Konrad
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« Reply #26 on: August 13, 2016, 03:07:57 PM »

A 12 x 6 folder is (usually) fine and the recommended size with this motor on 3S, but I guess you're looking for more usable RPMs with the smaller prop (haven't run the numbers thru MotoCalc yet).  Flex on the 12 x6???  From what company?

curious minds and all that...
In the bright light of day I see that Multiplex might actually own the prop molds as I see MPX molded into the blade boss.
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Konrad
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« Reply #27 on: August 16, 2016, 04:44:32 PM »

Stabilizer linkage.

Probably the most difficult engineering task is writing clear concise manuals. It was for me, while developing repairs for turbine engines. The stress analysis was easy, but getting somebody to understand exactly what was required and meet the FAA 9th grade mandate was taxing. (By the way most technicians understood geometry, physics and chemistry well past the high school level).

What gives me concern with the Heron manual is that the instruction said to place the linkage in the first hole of the servo arm. Well my Hitech HS65 servos come with three styles of output horns. With the first hole varying from 6mm to 9mm out from the center of the output shaft.

I settled on the hole that is 6mm from the center of the output shaft. This results in an elevator movement of +-12mm with 120° servo movement. The manual states to use +-10mm, I assume this is with 90° servo rotation.  The manual also says that you might have to drill the servo arm to allow the clevis pin to fit. It would have been nice if they had stated what the size of the clevis pin was. (Many folks don’t have a full set of metric drill bits, being able to get the drill bit while at the hobby shop would help some modelers). The clevis pin diameter is 1.5mm (0.060”), 1/16 is too sloppy as it is 0.0625”.

A possible issue I found is that at the 6mm hole location the elevator clevis will bind on the servo output shaft. I had to use a rotary tool to grind away part of the clevis arm to clear the output shaft at the extreme downward movement. I ground both arms of the clevis should I need to adjust for 1/2 a turn of the push rod.

I also found that the recommended thread adhesive would still allow the elevator the rotate far too easily when the stabilizer was dismounted. I used some small silicone (small fuel) tubing over the clevis body and push rod.

As a side note I place the servo arm pointed slightly up towards the stab with the radio in neutral (servo centered). This is to give some differential biased towards down. This is to give a better control balance feel with cambered airfoils (more down than up for the same amount of servo rotation).
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« Reply #28 on: August 18, 2016, 01:08:39 PM »

Very good set of instructions for setting up the Fry Sky Taranis Plus (Open TX) for an electric 6 servo ship. These are from Mike Shellim. I liked his step by step methodology with the Multiplex Profi 4000.
http://www.rc-soar.com/opentx/index.htm
http://rc-soar.blogspot.co.uk
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Konrad
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« Reply #29 on: August 22, 2016, 01:46:53 PM »

A little bit more on the mylar wipers.

I’m showing wipers being installed on an EF-1 Pylon racer, the E-Flite Shoestring.
As the 0.10mm (0.004”) thick mylar comes off the roll it will have a bit of a curve to it. We use this curve to preload the wiper against the surface. To do this place the double sided tape on the minor diameter, concave side. Since we want the mylar to stay up against the surface as long as possible make sure you don’t have it extending onto other surfaces such as flaps or as I’m showing the wing tip.

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Konrad
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« Reply #30 on: August 22, 2016, 04:52:39 PM »

Very good set of instructions for setting up the Fry Sky Taranis Plus (Open TX) for an electric 6 servo ship. These are from Mike Shellim. I liked his step by step methodology with the Multiplex Profi 4000.
http://www.rc-soar.com/opentx/index.htm
http://rc-soar.blogspot.co.uk
Sorry, that should read: Fr Sky Taranis Plus...

Even more on the wipers!
As I stated earlier EPO is horrible for getting anything to bond to it.  The best we have found is CA glue. I sand the area where the wiper will be placed to remove and EPO shine and any molding vent knobs with 220 grit sandpaper. I then apply a thin coat of thin CA glue. After is dries I sand this layer of glue with 400 grit sandpaper to break the shine and remove any fuzz. Then place the wipers as shown. (see attached end view of wipers on the rudder of the Heron. Cross head screw it just there to keep the elevator push rod out of the way)

While these wipers aren’t as good as wipers on surfaces that where designed for them (read $1000 glass slippers) they work real well even in these after thought applications.
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« Reply #31 on: August 23, 2016, 01:44:04 AM »

I agree for the effort required these wipers work well. I have used them on a quick overhaul on the flaps of a F3B model.
I did find that you need to be careful with the overhang on the moving surface - minimising it to just cover the surface on full deflection away from the wiper. Having a curved wiper as mentioned makes a big difference.
John
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« Reply #32 on: August 23, 2016, 10:22:47 AM »

Pardon a comment from someone with minimal RC glider experience but would very squishy foam fillers glued into the gaps work as gap seals?
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Konrad
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« Reply #33 on: August 23, 2016, 11:51:36 AM »

Thank you John. You bring up a good point. That is if the wiper moves away from the surface it will be the source of some drag.

I’m showing in one of my cartoons what we get with some of the higher end composite ships. The wipers are actually in the wing. This actually allows more motion before the wiper lifts (separates from the surface). Now if you extent the motion too much the wipers will pop out and bind in the gap. This is a real bad and ugly event as the servos will stall and burn out, with the result in loss of control.

In a foam hinge like I’m showing we get the added reduction in drag as the hinge line is much smoother than stock (from the OEM) in the neutral position. It also offers drag reduction on both sides of the control surface for most surface movement. True at extreme deflections the wiper might separate from the surface. But to my way of thinking the drag is still less than what we have with stock non-wiper equipped hinges.

As I mentioned earlier there is a danger with these wipers and that is that they can get caught in the gap and stall the servo. So while having too long a gap will add drag at extreme surface deflections, Having too short a wiper runs the risk of surface binding. I always try to error on the side of too long (wide) a wiper.
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« Reply #34 on: August 23, 2016, 12:13:25 PM »

Pardon a comment from someone with minimal RC glider experience but would very squishy foam fillers glued into the gaps work as gap seals?
Accordion  like materials have been tried. Your very squishy foam fillers glued into the gaps would work like that. The issue is making space for them and they all add a noticeable load on the actuator (servo). Adding load to the servo is never a  good idea as it limits servo life and hampers accuracy and limits the effective power available to manipulate the surface.
Now full size aircraft often use a felt like materials as a gap seal. These must be replaced as a normal part of the aircraft maintenance schedules.

While it is true that these wipers I'm showing often act as gap seals, limiting the bleed through of high air pressure air to the low pressure side of the surface. This is how they aid in adding control power. In most foam models the “live” hinge is already a very effective seal.

What I’m concerned with is drag (turbulence) from the hinge line. These wipers bridge that hinge line very close to the airfoil surface. It is hoped that this will allow the whole airfoil chord to function as the aerodynamicist intended.

These wipers and seals are not limited to sailplanes. All aircraft will benefit from there use. I show where I'm installing them on my entry level EF-1 Pylon racer, the E-Flite Shoestring.
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Konrad
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« Reply #35 on: September 15, 2016, 02:00:13 PM »

I see that I failed to show the improvement in the mounting of the wing control horns. With the Heron, Multiplex has added a barded end to the leg that extends into the control surface. This barbed end with the Heron detents behind the surface stiffeners. This is a much welcomed feature compared the the standard "T" mounting style.
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« Reply #36 on: August 19, 2017, 10:04:09 PM »

I just purchased a Multiplex Heron RR and joined this forum thanks to the excellent read posted by Konrad...  My Heron is backordered at tower hobbies but they assure me more are on the way. I hope to be able to get some time with it before it gets too cold here in northern Michigan.. It appears that for a foam glider, I chose correctly. Sure glad I didn't buy a radian xl!
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« Reply #37 on: August 20, 2017, 05:52:15 PM »

The Heron is a great stepping stone glider towards the high performance glass ships.

Can you tell us a bit about your level of experience.

The only knock against the Heron is that she needs rather advanced radio mixes to extract all the true performance potential (this is true of any multi servo winged glider). I also would like to encourage you to experiment with different prop blades.
https://alofthobbies.com/power/props/aeronaut-folders.html

All the best,
Konrad
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« Reply #38 on: August 20, 2017, 06:21:37 PM »

I ordered this Heron as a relaxing lounge chair glider. I'm typically flying hotliners/F5B airframes for sport although I did compete once many years ago (before lipo). I realize this foam glider will not even come close to matching the performance of my moldies but that's not why I ordered it. There are days I don't want to risk an expensive airframe and/or just want to relax and float around looking for thermals. I was indeed looking at the radian XL for a floater but fortunately yours (and others) reviews left me with the feeling I would not be happy.  My current flagship F5B is a 2 meter virage built by Yuri Virchenko running on 10s with Neu 1512/2.5D. It's a rocket and tons of fun to sport fly but I'm not always in the mood for launching or landing it.Some times spending a lot of money on a model makes it less enjoyable to fly, at least for me, the fear of a crash is always in the back of my head. The RR Heron cost less than just the motor in the virage so I'm not going to be stressed out if I total it somehow. I used to fly speed 400 class pylon racers too but found my blood pressure would skyrocket when flying them, they were no longer enjoyable for me and at the ripe old age of 60, I was having a harder time with orientation and staying ahead of the model. .. I have some old Graupner cam 12x6 blades I was hoping to be able to use with the Heron. I'm thinking these will be an improvement but guidance there would be great. I also have some aeronaut 13x7 blades that might be o.k.? The aeronaut cam/carbon 13x7's are off of an old FVK bandit.  I do NOT plan to mod the Heron unless necessary but since I already have these blades lying around I thought they'd be better than the flexible ones that come on the RR.  I really enjoyed reading your thoughts on the Heron and the Radian XL. I'm going to stick to 3S 2200 packs as those are very inexpensive nowadays. Gens Ace 25/50c for $15?? amazing. My radio is an Airtronics SD-10G so no issues there. I JUST moved to 2.4 a year ago.. EDIT: reading back I see that the graupner 12x6 should be an improvement, thanks. Will the 13x7 be too much?..
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Konrad
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« Reply #39 on: August 20, 2017, 07:32:24 PM »

The Heron sounds to be a perfect fit.

The Himax motor in the RR can handle the load of the 13x7 just fine.

I like a bit more pitch speed than most of the guys I fly with, so I usually end up with more pitch than stock.

All the best,
Konrad
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« Reply #40 on: August 20, 2017, 07:50:03 PM »

Excellent... I usually like at least the pitch to equal the diameter but I don't think that's feasible with this setup. My "speed" prop for the virage is 18x23.. That gets your attention.... I may start with the 12x6 on the Heron and then the 13x7 after a few flights. I'm really looking forward to getting this plane. I've never owned a foam glider. Some of the vids I've watched show some pretty disturbing wing flex. I will have to exercise some restraint. Now if only tower would get them back in stock!.. When I ordered it over a week ago they showed "mid Aug" for backorders and now they've changed to "late Aug"... I've been down this road before so I'm not counting on having it until Sept , if then. Once again, thanks for your in depth review/assembly posts. Far more detail than I've ever seen on an RCGroups assembly thread. Love it.
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Konrad
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« Reply #41 on: September 27, 2017, 02:08:31 PM »

I see I’ve failed to give my set up information and a fight report. Its time to rectify this oversight.  Shocked

Throws are:
Elevator    10mm up
                 11mm down

Rudder      20mm each way

Aileron       20mm up
                  17mm down

Flaps as     15mm up and down
Aileron

Camber     3mm reflex (Note Multiplex recommends 2mm)
                  3mm flap
Camber
Ele comp   1.5mm down

Crow
Aileron       27mm up
Flap           30mm down

Crow
Ele comp  2mm down

Motor        2mm down
Ele comp

Ready to fly weight is 1.52 Kg without the need for any ballast in the tail (no steel balls added) (Spec. 1.550 Kg).

I’m very happy with the elevator response with the set up shown earlier and with the CofG about 3mm to 4mm aft of the balance bumps.

I’m using a 3 cell Thunder Power 2700mAh battery. The ESC is a ZTW Beatles 60 (rebranded as an FMS 65 amp). The ESC needs to be thin to allow the battery to pass. With the Hacker A30-10L I like the Aeronaut 10 x 6 Cam prop blades*. This power set up is drawing 50 to 55 amp. For a nominal power draw of 600 watts. This is about the power limit for the plastic Multiplex spinner and prop hub. If going with more power (and I can’t see why) one needs to move to an aluminum prop hub such as the one Aeronaut sells. But this Aeronaut spinner and hub cost about $55, which is close to 20% of the cost for the whole airframe.
With 600 watts and the 10 x 6 prop I get a vertical  climb and more than enough pitch speed to perform any aerobatic routine I want.

I’m using a Spektrum DX9 as my sport radio. I have to say I’m not happy with my ability to control the flaps and ailerons while in crow. I don’t know how to program an, if this then that, type of mix hierarchy using the master slave protocols of the DX9. With the flaps and ailerons being at odds with each other, I’m forced to heavily rely on the rudder for direction (yaw and roll) control while in crow. The Heron does have enough dihedral to allow the rudder to over come this programing deficiency, be it mine or the radio’s.

Yesterday was a great hot day here in the San Francisco Bay area. It was the first time I was able to fly back to back most of my foamy gliders. I can unequivocally state that the Multiplex Heron is the BEST thermal foamy now on the market. Compared with the previous best the Multiplex Cularis. The Heron has a noticeably better airfoil. The airfoil, actually the whole ship, responds much better to being reflexed (speed mode). And with a few millimeters of flap she can really slow down and still produce lift in a thermal. This performance really comes down to the more modern Eppler cusp airfoil and that it is thinner than the one found on the Cularis.

I was pleasantly surprised that the thinner single spar Heron wing exhibited a lot less wing flex! The Cularis’s dual round carbon rods really aren’t the best geometry for a spar.  The Heron’s tall rectangle spar’s while being more expensive to manufacture really come into their own in this 2.4m wing. Also the plastic spar sockets and spine of the Cularis are very flexible. I have to admit I had some reservation about the cross over arrangement of the Heron’s spars. But in actually use it is showing to be much better way to mount the wings than that of the Cularis tube style sockets.

I will have to say that the Cularis seems to recover from upsets a bit better than the Heron. This might be due to the less critical nature of the airfoil and/or that she has  a longer fuselage with greater vertical fin area. It might also have to due with the what I have them trimmed. The larger vertical fin might actually be a liability on the Cularis as she tends to fall into the center of the circle (spiral stability) a bit more than the Heron.

I have to say it is difficult to find fault with the Heron. The only thing I see as worthless in the Heron is the battery hold down plate. I really had to look hard to even find this flaw in the design! Also the wing wiring plugs are a bit fussy. One needs a good set of finger nails to drive the connectors home.

Now I don’t want to over sell these great Multiplex 2.5m plus foam gliders, neither one of these can compete with that small yellow 2 meter carbon and kevlar sailplane (Astra?).  

For the $30 to $60 dollar premium one pays for this Multiplex Heron over the Horizon Hobbies Radian XL really is money well spent! Not only do you get twice as many servos but you actually get a modern soaring glider that can fly in many lift conditions. As a wise man said; Quality pays it does not cost!  This goes for gliders as well as a pair of boots!

* I tried a set of 11x6.  climb was a bit better in the vertical. But I think I lost pitch speed (and speed) in the horizontal. Also the added power (over 60 amps) was taxing the ESC and the loss of run time just wasn't worth any possible improvement in the climb. The Heron is NOT a warmliner! There is little sense in trying to get her to emulate one.

All the best,
Konrad
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« Reply #42 on: September 28, 2017, 07:43:28 AM »

Konrad:
I like your margarita stand.

I'm also enjoying your threads.

Smiley

Regards-
Dave

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Konrad
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« Reply #43 on: September 28, 2017, 02:21:29 PM »

Dave, Thank you!

I'm glad you'er enjoying the read.

I have to apologize, I hope my poor english writing skills hasn't made the read too difficult.

All the best,
Konrad
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« Reply #44 on: September 30, 2017, 08:24:43 PM »

I just got back from another picture perfect thermal day here in the San Francisco bay area. Yes, the top of my mouth is sun burned!

I’m seeing that many guys are having issues setting up gliders with fully articulated trailing edges. This shouldn’t be too surprising as the Heron and even the Calypso might be the first glider many have had that offer more than just RESm control.

I can’t seem to get new glider drivers to actually try a full Crow set up. Even though their mouth drop seeing what the glide slope of my models look like. To many this is just too radical a departure from how they understand a wing to work. One can lead a horse to water but you can’t make it drink. I’ll have to gently persuade them to try crow. It is a huge step, and a rather difficult one trying to get the program working correctly.

Now they are actually eager to set up camber changing Trailing Edges (TE). One of the “new” guys to performance gliders was having a heck of a time getting his glider to respond properly to reflex (speed mode). Again the set up is often counter to ones intuition. Changing the TE is in effect changing the pitching moment  and direction of the airfoil.  Most non-reflexed airfoils have a negative (downward) pitching moment  when generating lift.   It is the job of the stabilized to control this pitch moment (force). For most normal cambered airfoil the stab has to supply a downward force (up trim) to keep the airfoil at the proper angle of attack. Now airfoils with reflex cambers can actually have a positive pitching moment. These airfoils are often used in flying wing where on can do away with the force from a stabilized altogether. This is a big clue in how to set up the elevator trim compensation when bringing the TE of the wing up (reflexed).

When you reflex your glider’s wing you need LESS down force from the stabilized to maintain proper trim. This means that you will actually be adding some down trim when you reflex the airfoil. This guy thought that because the wing could not generate as much lift (lower Cl) with a reflexed airfoil, he had to trim a bit of up when in reflex.  This just results in a ship that falls like a rock rather than one that gains speed to cover ground. 

To test this out get your glider trimmed for constant speed in level flight. (I do this after finding the neutral CofG trim. For the heron this is about 4mm to 6mm aft of the balance bumps.) When the glider is in front of you and showing a you her side profile reflex the airfoil (raise the TE 2mm to 3mm). Without elevator compensation the glider will pitch up (drop the tail) and quickly slow down. This is just what we don’t want in a set up called speed mode!  Shocked  Now fly the same pattern but add some down elevator compensation to the reflex mix. What you want to see is the plane change its attitude point the nose down a little bit and now much to your surprise you will see the plane look like it jumped forward in speed. You want to add enough down trim to effect a very slight almost level dive. Too much elevator comp will result in the glider tucking under as she gains speed.  What you have done with reflex is removed a lot of the drag from the trailing edge of the wing allowing the plane to fly faster for any given loss of altitude. This means you will loose less altitude moving between thermals. 

The down side to reflex is that it is harder to read thermal activity (You are likely to fly straight through lift without knowing it). I use reflex to get out of sink. I then use theTE in profile (designed shape) of the airfoil while looking for lift.

Once I think I’ve found a thermal I drop the whole TE to add a bit more camber to help the wing generate more lift at the cost of added drag.

Now as odd as this seems with the TE drooped you will have to add down elevator compensation. The reasons are different from that of the reflexed airfoil. First the drag goes up faster that the coefficient of lift from the added camber. This means the ship will slow down. Slowing down will generate less lift. So to keep up the speed you need to compensate with some down trim or she will stall. Also the dropped TE may change the airflow over the stabilizer. Usually resulting in more down force (up trim) from the stabilizer. You will need to counter this with some down trim.

This is a quirk of high performance ships in that changing the TE of the airfoil, up or down, often requires down trim elevator comp.

Some other trim consideration.
When in thermal mode (TE drooped) the inboard flaps should droop a bit more than the ailerons to produce a bit of washout in the wing tips. This will help keep you from tip stalling the inboard wing tip as you core out the thermal. Later as you get better at thermalling you will use less and less of this rigged washout.

I often hear that aileron gliders are prone to tip stalling in a thermal. What I think folks are noticing is that the glider tends to fall (roll) into the core of the thermal. To test this out the next time your aileron equipped glider  is falling into the thermal (too tight a circle) give a slight amount opposite aileron. If it is a true tip stall the ship should snap into the center of your circle.  What I think is really going of is that as the glider is slowed the ship exhibits some spiral instability, the vertical fin is pushing the plane inward. Unlike the simple RES gliders true high performance aileron ships needs some opposite rudder (top rudder) applied to flatten out the turn and keep the vertical fin inline with the airflow (not be skidding into the core of the thermal).

All the best,
Konrad
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« Reply #45 on: October 02, 2017, 11:05:41 AM »

As this is a kit review of sorts I should mention that Multiplex even took the opportunity to improve the decals (stickers). The Heron stickers have a real nice semi satin finish that is close to that of the raw ELAPOR ® (EPO) foam. And the artwork is pre cut from the clear backing that makes up the stickers. Again a well thought out product!  I did notice one short coming. That is the dark servos in the tail can still be seem through the “VX” sticker that is covering these servos. I lay down some white Scotch plastic tape (34-8714-8896-0) as a base to cover the opening in the vertical fin prior to applying the “VX” sticker. (Note, there is a left and right VX sticker as they are slanted a bit.)

After my first few test flights my Heron was still a bit nose heavy as defined in the dive test. I normally don’t like to add stickers but as most of the Multiplex art work is aft of the CofG I added the decals. Now I’m loath to add manufacture of brand names to my models unless I’ve signed a marketing agreement. This may be a hold over from my involvement in professional auto racing. Nobody rides for free! Now I will carry a brand name if I’m truly passionate or loath the product or service.  As the Heron is head and shoulders above anything else in the foam glider market, and it seems to be getting little press, I decided to add the Multiplex name to my Heron glider. I couldn’t think of a better place to put the name than under the wings. This was done to help the Radian XL pilots in their next purchase, as they are looking up trying to reach my altitude in the thermal we are sharing.

All the best,
Konrad
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« Reply #46 on: October 02, 2017, 11:07:29 AM »

Well, the decals did not shift the CofG aft. This forced me to rearrange my equipment placement. I now have my RX against the very back of the equipment cavity with the antenna pointed aft, in a hole I burned in the foam for its placement. Following the RX is the rat’s nest of wires from all those servo extensions. This will make rebinding a pain! As I’m using a Spectrum brand of RX I have the satellite RX extension running forward in one of the stiffener channels. I’ve placed the satellite RX so the antennae are 90° to the one in the aft fuselage.  This is not the optimum location for the satellite RX as the battery might crush it in an abrupt stop. With the RX in the very back I’m able to push the battery aft to get that perfect balance trim.

Now an operational issue has come up. Multiplex has failed to supply adequate skid protection for the foam. This is one of the nice things we get in the 2.2 meter FMS/ROC “V Tail” glider, it had skid guards. I’ve tried to add some durability by added some skip plates I cut out of Team Associated “Chassis Protective Sheet” P/N 9787.

All the best,
Konrad
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« Last Edit: October 02, 2017, 12:14:02 PM by Konrad » Logged

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« Reply #47 on: October 03, 2017, 08:14:43 PM »

Well, today provided me a great opportunity to stress test the new wing attachment system Multiplex is using in the Heron. To save you from having to read all the gory details. It worked like a charm. I’m truly impressed.

The “event” started at launch when the ZTW (FMS branded 65 amp ESC) lost motor commutation at launch during motor speed up. It is my habit not to launch a high performance glider with the motor at full power. The glider got to about 3 meter height when the motor screeched like a car engine running out of oil! The Heron described a perfect parabolic arc, followed by a nose plant. (I keep thinking of Steve Windwood’s “Arc Of The Diver album). Nose plant is a bit extreme as I was able to get the Heron to rotate (flair) a bit right before impact. The force of impact jettisoned the wings.  I feared that firewall, nose and wing attachment area would all be damaged. Other than some dirt in one of the folding prop blades. All was fine. All I had to do was re-move the prop (spinner) and readjust spinner to fuselage clearances.  Oh, and reinstall the retention pin for the wings.

I have to admit this wing retention system gave me concerns when I first saw it. But after having flown some aggressive aerobatic flight routines and now stress tested it with a 3 meter dive to impact, I think Multiplex should give the engineer who proposed this system a huge raise!

Doing a bit more programing with the DX9. I was able to cut down the flap aileron response to about 10mm. This help with the power off roll rate. I also moved the CofG aft another 2mm, to about 6 to 8mm aft of the CofG dimples. At this balance point Elevator comp for reflex (speed mode)is less than 1 mm down, and about 1.5 plus mm down for fully drooped  TE (thermal mode). Still can't bring the crow TE into profile to affect roll control with the DX9.
« Last Edit: October 03, 2017, 08:25:49 PM by Konrad » Logged

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« Reply #48 on: October 04, 2017, 12:59:41 PM »

Found the issue with the ZTW Beatle ESC loosing commutation with the motor.

The option to change the Pulse Width Modulation (PWM) frequency is NOT on the programing card. This is odd as most “advanced” programing options are found on programing cards rather than in the TX stick programing menu. The ZTW Beatle ESC does allow for changing of the PWM frequency but it is in the TX stick menu. By default the ESC is shipped with the PWM set at 8kHz. But for low wind, high Kv motors often a higher PWM frequency is best. The other option is 16kHz. I found that the ZTW Beatle allowed for changing the PWM by reading the ESC manual.

There was no explanation as to why one would change the PWM.
So here goes, the higher the PWM the more stress is placed on the ESC. But the higher the PWM the more the motor windings will respond as if the current is supplied by a true DC source. With too low a PWM frequency the coils act as a choke and delay the back Electro Magnetic Force (EMF) pulse that the ESC is looking for to time the next shot of current (the ESC loose its commutation reference).

I’m also showing what I do to ensure that I don’t crunch up the antenna as I push the RX way back into the fuselage. I stiff plastic tube is used as a sheath to keep the antenna straight.  I also added an EPO ramp to try to protect the satellite RX from the crushing battery. It proved very effective in loss of power launch!
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« Reply #49 on: October 04, 2017, 09:43:19 PM »

I really enjoy your thoughts and explanations on this thread Konrad.  I was considering a DX-9 when I switched to 2.4 but after reading how many glider pilots swore by the Airtronics (sanwa) SD-10G and their huge drop in price since they are no longer sought after due to lack of telemetry, I bought the Sanwa and have really been enjoying it's ease of programming and templates for gliders, not to mention the rock solid link. Crow brake is super easy to set up and no satellite rx is needed with this radio.  I have been experimenting with camber and reflex and found with the recommended down EL compensation for reflex, my heron gained too much speed for my liking. I also have less down compensation that recommended for thermal camber. I find it easier to have neutral EL for reflex and manually add some down EL if I want to cover ground more quickly. I rarely use reflex so it's not a big deal for me. I just received some expensive 3s 2200 lipos to try out. They are the new Hyperion G7 silicone/graphene and I believe the C rating is 65. I won't be needing that high of a C rating when drawing less than 30 amps but the packs were a "gift" after having bad luck with a Hyperion G6 high voltage (4.35) pack. I went to the flying field today anxious to try the new packs but the wind was ridiculous and I decided to go home with an intact airframe instead. Next opportunity will be Friday. Our flying season is almost over here and its a shame because I'm having so much fun with the Heron.  I added neon green trim sheet to my wing tips and rudder and it shows up nicely. Bottom of the wing is red and simple clear tape for abrasion protection.  No issues with my Heron yet and I probably have 40 flights with it. The other club member I talked into getting one had a flap servo fail on his maiden flight. I did notice he didn't raise flaps before touchdown, a real no no..  He is another one that is nervous about trying crow. Another new glider pilot in our club also refuses to try the crow brake. I showed him how it works both with a spot landing demo and having him watch the ailerons go up as the flaps go down. His response? "if the flaps go down and the ailerons go up, they cancel each other out".. I was at a loss for words. He lands with flaperons only. SMH
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