TopModel Samsara 3.2 meter glider, build thread on Aloft's Forum.

[Konrad]

Thank you James,

That is my modus operandi. Along with questioning, usually of management and the leadership, I also try to offer my reasoning as to why I do the things I do.
This is to help others apply these lessons I've learned to their own situation. But what I hope it also does is bring to light any fallacies in my logic. And gives those that are truly learned of the subject a chance to correct my misconceptions.

I always hated it when my parents, teachers or my bosses would tell me "because I said so". This to my way of thinking was just short of an admission that they were ignorant of many of the variables at play.
It is through this detailed exchange that I learn who is the real source of knowledge. This really applies to my vendors. Far to often I ask a question of a vendor and get a lot of double talk so much so than my head spins leaving with the feeling of Motion sickness.

What I really like about Wayne and the crew at Aloft Hobbies, is that they really are technically well versed and competent with the products they sell. And here is a huge difference between Aloft Hobbies and say vendors like MotionRC, if they don't know the answer or solution to a technical/engineering problem they will tell you so. There is nothing I hate worse than a sales guy lying to my face! I work far too hard for my money to give it over to fools and thieves.

 

[Doc James Hammond]

Thank you James,

That is my modus operandi. Along with questioning, usually of management and the leadership, I also try to offer my reasoning as to why as do the things I do.
This is to help others apply these lessons I’ve learned to their own situation. But what I hope it also does is bring to light any fallacies in my logic. And gives those that are truly learned of the subject a chance to correct my misconceptions.

I always hated it when my parents, teachers or my bosses would tell me “because I said so”. This to my way of thinking was just short of an admission that they were ignorant of many of the variables at play.
It is through this detailed exchange that I learn who is the real source of knowledge. This really applies to my vendors. Far to often I ask a question of a vendor and get a lot of double talk so much so than my head spins leaving with the feeling of Motion sickness.

What I really like about Wayne and the crew at Aloft Hobbies, is that they really are technically well versed and competent with the products they sell. And here is a huge difference between Aloft Hobbies and say vendors like “ MotionRC”, if they don’t know the answer or solution to a technical/engineering problem they will tell you so. There is nothing I hate worse than a sales guy lying to my face! I work far too hard for my money to give it over to fools and thieves.

Aye to all of that.

Be careful about offering your reasoning to the general public though. This has been my undoing many times.

I honestly thought that sharing what I do and why I do it would be helpful - after all designing airframes (not the model ones - that is really just a hobby) is my job and people pay me for it so I should have half an idea that I know what I'm talking about. There is quite a lot of stuff that flying over our heads right now and looking down on us - hopefully protectively - that was designed by me.

However, to some, answering questions, and sharing knowledge paints a target on your back, and they will come after you. Why this should be is not only highly disappointing and sad, its also something that I completely and utterly do not and never will understand. Happily these people are few and far between, but they do exist.

Maybe I'm too old, maybe I grew up in a different generation where helping and sharing information were good things.

I like things to be genuine and and honest.

I design and make model aeroplanes because they are toys, expensive ones at times, but toys nonetheless and they are toys I love to play with.

Thats why, like you, I do appreciate Wayne and his hard working crew. They know what they are taking about and will tell you and give you sound advice. And if they don't then they will do thier best to find out for you.

More power to them say I!

haha! Rant over! Sorry guys - lets go flying!

James.

 

[Konrad]

I have been involved in the design of full size aircraft, systems not airframes. Years ago I had some successes competing on the national level making toy airplane engines (FAI F3D). And I also carry the mark of my age (mid 50's), gray hair. You should hear the cries from the masses when I call our toys, "Toys"!
Now I've come to the conclusion that ignorance is a cultivated product of much of todays marketing. The information highway has become little more than a train wreck.

So true about Wayne and his crew, they will try to find the correct answer and not leave you hanging to dry in the wind.



You Can't Push a Rope! - My mechanics professor

The dirty little secret for this build is that most of the work is related to wiring.

I've chosen to stay with PWM servo architecture as this is an entry level model there is a possibility (very, very slight) that I'll sell her to an up and coming flyer.

Now I am using a common power bus bar to drive the servo on each halve of the wing. I've made up my wiring loom from 22 AWG for the red and black (pos & neg) power leads. To save weight I decided to use 26 AWG for the white and yellow signal leads. I also used 26 AWG for the flap leads after tapping into the larger 22 AWG power leads. This results in only needing 6 wires and pins to drive all 4 servos.

I twist these leads to aid in noise cancelation. Flat ribbon wire is fine for robotic assembly, but can be troublesome as they act like antenna picking up all sorts of noise.

To help push these leads down the wing tubes I hold the ends together with some heat shrink. It is akin to pushing a rope so be prepared for a bit of a fight. (Sorry, the photo should say 4 not 6 leads)

Here are some of the materials I use. I could have sworn that I got my crimp on pin from Aloft, but I can't find any on the site.



22 AWG 26 AWG wire leads
https://alofthobbies.com/servo-wire.html

Crimping tool
https://alofthobbies.com/sb-225d-ratchet-crimping-tool.html

Pins
https://www.amainhobbies.com/protek-rc-futaba-style-servo-connectors-4-pair-ptk-5008/p17873

 

[Konrad]

A left over practice of mine, from my slimmer days (glow fueled models), is to try to seal all edges. On the servo opening I feel that turning under the covering gives it some stability when shrinking it (won't pull away from the opening).

 

[Wayne]

Thanks for the kind words - One thing I learned long ago is to be honest, if you do not know the answer, best off to tell others that you do not know. Nothing worse than handing out bad info. I am very embarrassed when it turns out that things I took for fact turned out to be false. It happens, especially as this hobby gets more and more technical. It is really tough to stay on top of it all. We tend to be picky about the products we offer for exactly this reason.

 

[Konrad]

Wayne,
I don't want to sound like a sales employee or an agent for Aloft Hobbies. But, do you carry the crimp on pins to make one's own servo extension?

 

[Doc James Hammond]

A left over practice of mine, from my slimer days (glow fueled models), is to try to seal all edges. On the servo opening I feel that turning under the covering gives it some stability when shrinking it (won’t pull away from the opening).

View attachment 239View attachment 240

Good stuff Special K!

 

[Konrad]

Ha ha, that's a new one for me!

All the best,
Mr. Kay
(This was my professional name when I was building Camel GT light cars. But that was in a galaxy far, far away).

 

[Konrad]

Time to solder the 6 pin Multiplex connector. Please heed the advice given here.
https://forum.alofthobbies.com/index.php?threads/wiring-harnesses.130/


A requirement of all aviation soldering spec's I've read state that all flux must be removed. This includes the electrical safe rosin core solders. I like to use denatured alcohol as my flux solvent after all the soldering is done and before shrinking the heat shrink. Please note that there is an added quality feature and that is I've added a strain relief to the wire loom.

Now if your wife is like mine and has lost any sense of humor, she might have had, as a result of you burning her fingers. This solder fixture makes life, both your modeling and personal life, a lot easier.
https://alofthobbies.com/soldering-jig-kt1802b.html

 

[Konrad]

It is understood that the ability to see the wing at altitude is highly dependent on the surface area rather than wing span. In my opinion Top Model has made an error using only those small transparent insert panels for color on the bottom of the wings. It has been my experience that this covering pattern limits the visual altitude for this 3.2 meter ship to be even lower than a typical 2 meter ship. To correct this in the ARF model I've recovered the bottom of the outer wing panels with transparent red. I hope the side by side comparisons makes it clear as to which is the easier to see. Hint; It is the red panel

I can confirm that the OEM covering is NOT Oracover-lite. I measure it as being around 0.04mm thick. The Oracover-lite I used has a thickness of around 0.02mm. (I only measured the red covering. The white actually felt thicker and heavier, but that might have been just a trick on its opacity).

As a result of the use of Oracover-lite and that I took the opportunity to clean up the structure a bit (sand and pick off some glue blobs), the recovered panel is 7.5 grams lighter than it was prior to recovering.

 

[Wayne]

I believe they are covered in normal Oracover. Why? It holds up better. At least that is my wild guess on the matter.

When it comes to visibility everyone has their favorites. For me it is a solid color(s) with high contrast stripes from the leading to the trailing edge. I also like to have a small contrast of color out on the tips. My vision and depth of field needs all the help they can get.

She is going to be a pretty bird!

 

[Konrad]

As purchased she is a beautiful ship. I just hope I don't mess it up!

Yep, that is my understanding that the model is covered in full weight Oracover®. Since Top Model does not own the trade name "Oracover", they are obligated to use real Oracover® if advertising as such. Unlike say Hobbico/Great Planes which owns the trademarked name "MonoKote®". Great Planes can use any shelf paper they want and still call it MonoKote® (AKA Moneykote).

While I"m sure that the full weight Oracover® is nominally stronger that Oracover-lite®, I know it would make little difference against the weeds I land on. Now I know that high end firms like FVK and Vladimer Models use Oracover-lite® on comparable size models. While the weight saving isn't significant, it is very noticeable.

True, youth is wasted on the young! I like to use opaque dark red or black on the bottom of my wings. As the sky is the light source (as opposed to reflected light) dark colors show up best against the bright sky. Now I'm willing to concede to fashion and use transparent film on open frame construction, purely for the esthetic joy of seeing the light filtering through the covering and structure. But as I said earlier if I was to buy another Samsara (and I just might) it would be the ARC version.

 

[Wayne]

Yeah, I was going to comment on the transparent film, but I agree, too darn pretty to close up a built up wing, and these are no exception!

 

[Doc James Hammond]

Not too sure about the Viz - I'm long sighted.

Buuuuttt!

Like both of you chaps I LOVE the light through built up wings!

Takes me back to my youth let me telleth unto you!

Which to be honest is a lot of the reason why I bought this model from Wayne while I was there last year.

I have not flown my bird yet but the weather is improving!

Cheers,

Doc.

 

[Konrad]

I can't say as I was immune to the siren call of her long wings. But it was the long one piece (not a pod and boom) design of the fuselage that grabbed my heart strings (AKA wallet).

I hope that Top Models will be using this fuselage in a range of other model offerings.

 

[Doc James Hammond]

I can’t say as I was immune to the siren call of her long wings. But it was the long one piece (not a pod and boom) design of the fuselage that grabbed my heart strings (AKA wallet).

I hope that Top Models will be using this fuselage in a range of other model offerings.

I have a bit of a thing about fuselages as I have designed so many.

I like the Samsara but its not on my all-time greats list.

Doc.

 

[Konrad]

True! But for a $400USD ship, I'm impressed that Top Model is actually making and shipping these 1.8 meter long fuselages. The box for the Samsara is very long and I'm sure the shipping eats into any profit margin there may be. Most 3 meter ships are lucky to have a fuse that is even 1.5 meters long, unless they are two piece pod and boom.

Am I showing my snobbery, but Top Models isn't a high end OEM? Rather to my eye they are a purveyor of good value sport models.

 

[Konrad]

Setting up the elevator servo to fit inside the tail fin. The manual makes no mention of this. I'm using a 7mm arm length as this with the KST X08 still allows the ball joint to clear inside of the fin all the way back at the tail post.

It is wise to make sure that the ball stud clears the body of the servo. I had to file mine to clear. Also don't use Loctite thread lockers as they will break down the plasticizers in the plastic arm and making it very brittle. I lock the nut with a drop of thin CA glue.

 

[Konrad]

Per the manual The servo outputs are placed at the front. For the rudder this makes sense as it allows the rod length to include the threaded coupler (clevis). On the elevator I thought it might be done to allow the servo's rotational axis to align with the thickest part of the fin's chord. Now I don't think there would have been any issue flipping the elevator servo should I have needed to make clearance for the servo motors.


After installing the elevator servo I noticed that even with the 7mm long servo arm I still have over 1mm of clearance. This means that with a 7mm arm one can still use a servo that is 10mm thick (The KST X08 in 8mm thick).


Note: That I made a custom elevator push rod from 2mm wire. A 2 mm threading die is a great tool to have (left over from my helicopter days). As both ends are threaded one needs to use jam nuts in an application such as this.


I just tested the elevator servo and rocker and have found that I have more than enough servo motion to bind the rocker bed at both ends of its travel. This leads me to think that a 6mm servo arm would still allow enough elevator movement. I like to use 100% to 120% of servo motion to get the best servo resolution. I also placed the servo arm pointed aft about 15° for neutral center. This is an attempt to get a bit more linear elevator response with the rocker that has the effective control arm pointed very far aft.

 

[Konrad]

I had assumed that along with trying to get the most servo arm movement for the elevator I'd need to do the same thing for the rudder. This is not the case! In fact we really want to get the servo's center of rotation close to that of the rudder hinge line. Maybe even a bit closer to the right (starboard) wall of the fin. Keeping the servo buried deep in the fin makes it difficult for the rudder push rod to clear the rudder post. The hood on the cover allows for keeping the arm and rod somewhat streamlined.

To correct this error I had to add another 3 mm to the plywood mounting pads for the rudder servo.