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

[Glenn Beer]

If by hi res you mean 1080, it’s there. You just have to select it for playback. Youtube seem to be doing everything it can to drive users to its premium service. Like defaulting all playback to the lowest res version of the video.

 

[Konrad]

THANK YOU!

That's what I wanted to see. One can see that I lost my heading by 90° at the top of climb.

 

[Konrad]

Well I decided to fix that broken rear spar. Much to my surprise I didn’t need to recover or actually make a patch. As a result of the color part line I was able to peal off parts of the covering without damaging the pieces of film.

With the break exposed I aligned the parts I then soaked the break in water to expand the balsa fibers. (Recall that this spar had failed in compression). I did not sand the joint, rather I used the iron to smooth down the fibers. After this area dried I soaked the break with thin CA glue. I then re-ironed down the lifted covering. Much to my surprise this area is stronger than the same area on the other wing!

With the water soaking I was able to maintain many of the original wood fibers across the break. This contributed to the strength of the repair. While the repair is stiffer than the original, I'm sure it isn't as shock tolerant as the original un-broken structure

All the best,
Konrad

 

[Konrad]

I’m sure it is just a coincidence, but after I post a few flight videos showing loops and roll the Samsara is out of stock at Aloft Hobbies.

All the best,
Konrad

 

[Wayne]

LOL - Been waiting for it to go out of stock for a while.. Maybe your videos pushed it over the edge. I am thinking of discontinuing this plane in favor of the Element. Thoughts? I like both, and the Samsara does offer a lower price point.

 

[Konrad]

That’s a tough one. But as my LHS I think sales should be the main driver.

From my perspective (never having flown an Element) they look to have much the same performance. What the Element gives up to the “D” tube wing of the Samsara it might make up in wing span. I like the “D" tube a lot more than the sagging covering of the carbon tube spar wing. I think the carbon tube is not using the carbon to its fullest potential.

For my style of flying I like the flatter wing of the Samsara. I get real nice flat coring circles with the opposite ailerons in a thermal.

So I’d give the Samsara just the slightest edge over the slightly bigger Element for my style of flying. I will say that the Samsara is the best flat land “ARF" soarer I’ve ever owned. A lot of this is due to that long 1.8 meter fuselage and that she is a full house ship. The Element also has both these properties.

If given a chance to take away ether of these ship in a raffle I’d take the Element only because I don’t have one. If looking at them based on the engineering merits I’d go with the “D” tube Samsara.

Now if spending my own money there be no doubt I’d get the Samsara again. I don’t see what the Element has that justifies its $150 premium!

Should ether wind up in my hands I’d want the uncovered ones. As it would allow me to correct the few minor issues I found in my Samsara. Mainly that the ailerons and flaps are too heavy. I also feel that these ships would respond well to the lighter Oracover lite covering film.

I fear that the market has erroneously labeled the Samsara flutter prone. Maybe, but I know it is more durable than the E-flite Radian XL, that would have gone into flutter on the back side if it had to make that 100 foot loop. Yet, the Radian XL has some ill advised supporters.

I will say that the Samsara is not a beginner’s soaring ship. She does need an understanding of sailplane programing and one needs to understand how to find the optimized center of gravity. She will also pay huge benefits if the proper equipment is selected. I assume much of this can be said of the Element.

As I don’t think there is a nickels difference between them I’d save the $150 and go with the Samsara!

All the best,
Konrad

P.S.
From a marketing perspective I think the solid colors don't sell as well with these open structures. I think the Samsara needs more color on the bottom. As the Element is the newer model if I were a dealer I'd get 2 of those and 2 Samsara, all with transparent colors.

 

[Konrad]

I found this on the web. It is a bit disconcerting to see the pultruded spar fail on the Top Model's Element. But it is to be expected as pultruded rods don’t offer much resistance to torsional loads. This stabilizer looks to be designed with only one carbon tube to deal with all the loads (both torsional and bending). Not a wise design. A proper design would be to use two spars tied together to resist flutter. I suspect that this particular spar might have been a bit dry.

Reading the post I think the owner is placing much of the blame for the failure on the TE window not being well constructed. I’ve always thought that most of the structure aft of the spar was primarily an aerodynamic fairing and a secondarily a structural feature. I don’t think the poorly constructed TE was the primary cause of the failure.

Now the fact that the pilot was able to save this model is an indication to me that the stabilizer might be too large. To save weight and drag I might have to think about shrinking the stab on my Samsara. But as designed I do like the response of the Samsara to changing air (signaling lift and sink).

As the Samsara has the same designed stab, I'll need to keep a close eye on it. I'll also have to give it an inspection on the rare event I fly into flutter.

All the best,
Konrad

 

[Konrad]

I just noticed that the wing main spars of the Element are not Pultruded but rather wrapped. These offer far more resistance to twiting (torsional flight loads). I'm at a loss as to why Top Models went with Pultruded spars on the stab for the Element and Samsara. All I can think of is follow the money. Pultruded tubes are a lot cheaper!

 

[Konrad]

Looking over my post history I've noticed that it might look like I'm stalking one of our forum members GQuiring. I need to apologize for this. I really am not stalking him. Rather his great photos often show in detail what I'm trying to get across.

I'd like to invite GQuiring to post more here on Aloft's forum. I'd also like to ask him what are his impressions of the Samsara and Element as he owns both.
(It is his photos that I lifted showing the stab spar damage, I did the annotations)

gquiring

forum.alofthobbies.com

All the best,
Konrad

 

[Konrad]

I need to thank GQuiring for posting on the internet the failure of the Element stabilizer. (Since RCGoofs won’t allow linking to “competitor’s web sites". I’ll try my damnedest to not to link to RCGroups!)

The 45° fracture is a strong indication that the spar failed in torsion. What I think happened is that the stab went into flutter. (A single pultruded spar structure is very weak in torsion!) This broke the LE to center joint. The kinked LE doesn’t help. With the loss of the little torsional support from the LE, the single spar twisted and fractured!

Since the Samsara is using the same stab, I decided to repair the stab before it failed. As an internet exercise I tried to come up with a fix for the poor design of the LE that would not need new covering. With a dull #11 blade I was able to lift all 4 layers of film covering with little or no damage to the film. I then applied 3 layers of 0.7 oz fiberglass with 15 minute epoxy. This glass and epoxy will add a great deal of durability to the LE joint. As it comes from the OEM the LE glue looks to be a brittle CA with no fibers to aid in distributing the loads.

Normally I would have stripped the covering (it would have been much easier and faster). Done the repair. And then recovered with Oracover light. This would have taken a few grams of weight off the tail. Maybe allowing me to save 5 times that weight saving in the nose.

All the best,
Konrad

 

[Konrad]

To quote John Lennon: “I’ve got blisters on my fingers!”

After the epoxy set I was able to recover the stab with the old film.

This was a problem in that there is no overhanging film to help keep tension on the covering. Even with the use of tweezers I still burned my fingers on the MoneyKote iron!

Better than new!

All the best,
Konrad

 

[Konrad]

I choose 3 layers of 0.7 oz cloth rather than one layer of 2 oz cloth for their ease in folding over the leading edge. Also I was able to stagger the layers to minimize the bump on the center rib and leading edge.

I choose to iron down the covering before the epoxy had fully cured. This was done so I didn’t need to sand the area smooth. The heat and pressure from the iron allowed the partial hardened (almost hard) epoxy and glass to flow resulting is a smooth finish.

 

[Konrad]

Again I just learned from the Web that it looks like TopModel has come up with a fix for the Stabilizer on the Samsara and Element.

They’ve add a second spar. (This should have been done in the first place)! This spar reinforces the leading edge kink (break). It also offers some anti rotational benefits to aid the main spar in resisting flutter.

I not sure but it also looks like the main spar may have been upgraded to a spiral wrap design (not a pultruded design).

I also see where they added a set of gussets to the rudder cut out window.

This is a vast improvement over V1.ohoh! But if starting from a clean sheet of paper I’d have done things a bit differently. Mainly I’d try to get as much distance as practical between the spars. I’d move the main spar forward as far as the wing tip ribs would allow. I’d then place the secondary spar as far aft as practical on the center rib. If I had the weight allowance I’d tie the two spars together with some diagonal bracing two or three bays out. I don’t see the need for the window gussets. Any issues here should be addressed by the build quality.

I’m confident that tying the leading edge (LE) together and bonding it with glass to the center rib is a stronger structure for any given weight as the LE can act as the missing anti-rotation structural element.

I've heard that even the new stab has failed. I haven't seen this, so I don't know how it failed. For all I know a tx was dropped on it, before flight! (I did this early on in the flight testing of my Samsara! )

All the best,
Konrad

 

[Konrad]

Went flat land flying again with the Samsara. Today I had installed an AMRT F5J-USA unit to practice F5J techniques. My understanding is that in F5J ones motors around for 30 seconds at the lowest practical altitude looking for lift. Once one finds this lift one adds energy to the airframe by going to full power full speed (level, not gaining altitude). At the 30 second mark shut down the motor and convert this speed into altitude and start riding the thermal.
https://alofthobbies.com/cam-f5j.html

Again I need to make it clear that the Samsara is not a F5J model. But then again she is less than 1/4 the cost of a full blown F5J model. I was a bit surprised that even at a bit under 2Kg the Samsara did not zoom as well as I had hoped. This is an indication that the airframe has a bit more drag than the composite F5J models. It might also be that I’m not getting the Samsara moving very fast prior to motor shut off. I’m loath to add any more speed by upping the pitch as the Samsara’s wings are a bit flexible. Again an issue that most composite wings don’t have. So on the powered portion of the flight the Samsara is at a noticeable disadvantage.

In a thermal the Samsara can hold her own, but one still notices the added weight and drag. The Samsara does thermal well so a competent pilot can hold his own but is at a slight disadvantage.

Now the strong point of the Samsara is in her long fuselage. She really signals thermals very well, this is her strong point. She lets you know where the thermal is. This is key to any thermal duration ship. Any of the advantages of the composite F5J ship are lost if one can’t find the thermal! While most 1.5 meter long composite F5J models can out fly the Samsara while coring a thermal. The Samsara with her 1.8m long fuselage seems to do a better job of telling you where the light thermals are. This is important in that you can’t climb in sinking air, regardless of how much money you spent on a composite ship!

All the best,
Konrad

 

[RWallage]

I am getting rid of a bunch of hangar queens, and when done I want to replace my old, old e-Bird of Time. Up till now I had been eyeing the TM Albatros Classic. But now I stumbled upon this Samsara...
Very little is written about the Albatros,so I have been somewhat doubtful. So maybe the Samsara is the answer.
2 quick questions though; can I use HS82mg servos al around? The elevator setup is very similar to the Nike I used to have, and there I constantly had problems keeping the elevator attached. The thread in the plastic seat would not hold the bolt. In the end I sunk a nut in the plastic. Has anyone had any problems with the elevator seating?

 

[Wayne]

The TopModel T-tails have some issues that need to be addressed during the build. Once fixed they should be trouble free, but by design I find them lacking. For the most part we do not offer their T-tails for this reason. The one exception to this rule is the Thermik Dream as we get a lot of requests for this plane. We are currently building up one of these for the shop, should see a build log from Nigel pretty soon. It is his first big thermal build. The plane he is building has already had a hard life, it arrived with heavy damage from forklift blade going through the fuselage. LOL We ordered up replacement parts, but I would never resell a plane that has gone through this sort of carnage, I'm sure we will have a good time flying it.

Yes, I think the HS-82MG will be a good option for the Samsara. I might opt for a nicer servo for the elevator, but that is just me. The Samsara is a lovely plane if you keep the speed down, at higher speeds she can get into some flutter. I think this build thread talks about that a fair bit. One of our local pilots has a Samsara and he really loves it. When asked about the flutter concerns, he tells me he has never fluttered it. He really enjoys the looks and ease of thermal hunting. It does look great!

 

[Konrad]

I love my Samsara. I've been flying mine just about every time I go flat land flying.

I've been flying her so much in the last 2 years that she is way over due for a recovering. I need to find another 3m thermal ship to fly as I bring my Samsara into the maintenance rotation. At $400 another Samsara is actually looking real good.

I need to level set expectation. The Samsara is no replacement for the tank/brick that was the Great Planes ARF (E)BOT. If you have a kit built (E)BOT you can expect about double the soaring performance from a properly set up Samsara.

The Samsara is a high performance TD ship. She is not a competition ship but she is a high performance ship. There are two big differences between the (E)BOT and the Samsara. First is that the Samsara is a full house (7ch) glider. The BOT is a three channel maybe 4 channel with motor. Aileron thermal ships are flown a whole lot differently than rudder elevator ships. Also being able to use crow opens up a lot of flying areas, as the needed landing zone is much smaller with the Samsara in crow.

Not sure what issues you have with Elevator seating. Is this a problem with the stab moving around on the mounting platform? Or are you stripping the threads on the bed and nylon bolts? I take my stab off almost every time I fly, as I have a small car. No problems, I tend to just tighten down the screw with my thumb nail.

T tails have a structural issue in that the mass of the stab high up on the tail puts a lot of leverage on the tail boom right at the LE of the vertical fin. ( I often fill the tail boom here with expandable foam to keep the boom from collapsing. This isn't an issue unique to TM)

Now to the specifics of the Samsara. Yes, I had flutter issues during my test flight. Once I got the CG set and the weight down below 1.9Kg. I've had no issues with flutter. I go into great detail here on the Aloft Forum as there is a lot of bad press about the Samsara going into flutter. Keep the weight below 2kg and set the CG at about 87mm and you should be fine. You can see in my flight videos that she will climb vertically, loop and roll without going into flutter. What more could one want from a light open bay balsa, thin, "D" tube wing,? True she isn't a speed demon ,so don't fly her like one!

The HS 82mg will have more than enough performance for the Samsara. But and this is a big but they are not suitable for placing the servos in the tail! The Samsara has a super long tail boom (This is what makes the Samsara the magical ship she is). 40 grams of servo weight in the tail will kill the performance from the Samsara. With that much tail weight it will be almost impossible to get the flying weight down below 2.1Kg. Heck, 2.2kg will be a problem. This added 0.3kg to 0.4kg of mass may make it difficult to stay away from flutter.

If I do another Samsara I will look for a heavier motor. I currently have a 160 gram motor in mine. If I can use a 200 gram motor way out on the nose I can drop down on my battery weight more that the addd 40 gram motor weight. I fly on a 4 cell 2250 and after a day's flying rarely have I used 1000mAh of battery's capacity. With a heavy motor I should be able to drop down to a much lighter 1500mAh or 1300mAh battery.

If you haven't flown a long tailed TD ship you owe it to yourself to try one. At $400 the Samsara is a great ship to see how a 1.8 meter fuselage compares to the standard 1.5 meter fuselages.

All the best,
Konrad

 

[RWallage]

Just to be clear, I am no stranger to full house F5J gliders, having campaigned one of the earliest K3600's and now a 4 meter Enigma.
I converted/build an ARF Dynaflite BoT to e-Bot and added spoilers for a friend of a friend of a friend, who (literally) dissapeared before I finished, leaving me an email to have fun with his glider... That was years ago, and she is now in dire need of some TLC. However, as the Dynaflite ARF BoT is not of the best of qualities, I am not willing to invest too much time and effort in her. I love the silhouette of the BoT in the air though. That's why I was looking at the TopModel Albatros Classic.

The picture you show of the elevator seat, is that standard? I see there is some kind of metal thread in there. On my Nike I had the same seat, but entirely made of of plastic with the thread for the hold down bolt in the plastic. The plastic was too soft and the thread wore out pretty quick.
If I'm getting the Samsara, I will probably aim to install the tail servos in front of the CG.
Still need to sell of one more hangar queen, and we're "all systems go"...

 

[Konrad]

Ok, if you fly a K3600 you are aware how the Samsara flies. The Samsara doesn't have the performance of the K3600 or Enigma.

Yes, the stab rocker is stock. It looks to be well designed in that the parts are keyed together and it is made of GRP (G10?).

I think others have tried the under wing servo mount but with less than stellar results. True the Samsara doesn't fly fast enough to benefit from the very short push rod runs that the tail mounted servos offer. So it might be practical, but the tail boom is narrow at the rocker bed. A carbon elevator push rod and pull pull cables for the rudder might work.

 

[Wayne]

If you are on the fence, might want to grab one as the price will not be able to stay at $400. With the current Euro exchange rate everything from Europe is getting more expensive. That and shipping costs are higher as a result of Covid. Not sure why that is since they aren't exactly paying employees more and fuel costs actually dropped. Anyone? Anyhow, they will probably go up $100 the next time we get them in. I have been a bit shocked by the exchange rate lately.