papaone

Hello

There is a new Lassi Nurila's pattern biplane named Glacial on his website.
Model kits | Nurila
claude

ted32776

I've watched him develop this model over the last year. Awesome workmanship and design. Originally, I had asked about his experience with pull/pull on elevator/rudder since he had it on one of his older models. He said it had worked out great and apparently continues with it on the new Glacier. It's expensive to get here in USA but clearly the workmanship is the best available.

wattsup

My Feedback: (1)

Ted, baed on what is currently available here in the States, I absolutely have to agree with you! The design, quality and craftsmanship of the Glacial is definitely a clear cut above the rest. I, for one, would be more than willing to pay the difference just to get a "quality" pattern plane for a change!

ted32776

Yes, it's eye candy for sure. At current exchange, it's about 3400.00USD in white plus shipping [last year would have been about 400-500.00 but today probably much higher]. I think he made subtle changes after flying the prototypes, may have even changed the molds accordingly. If you follow his progress in competitions, he is always "right there" near or at the top. Based on the various topline models he used to fly, I'd imagine this is a very good airframe. Certainly would be nice to have one!

wattsup

My Feedback: (1)

Ted, I find both of your responses very interesting. Your know I learned long ago that "you get what you pay for" and in today's pattern environment, the same set of circumstances apply! Consider this, why would someone buy two second rate airframes when for the same total amount of money spent, you could get just one Glacial and not fight the nightmares!

ted32776

You're correct, but I like to build so I've been looking more at models like the TopStage and Interceptor for my winter project. Seems most of my free time is late at night and there's not much flying going on then. That being said, there's also a dose of "fooling myself" in there as well . With the current price of either kit plus the "just quoted" 400.00USD for shipping from Morris/Japan, things quickly get costly to "build". Nurilla might have a lengthy lead time so my decision may be simpler. I'll send him a note and see what reality is.

wattsup

My Feedback: (1)

Ted, in recent years (out of self defense) I've learned the proper way to build and now I love it! There's a sense of pride upon completion that even a good "plug and play" can not duplicate. I'm sure, given enough time, you will find a kit that will suit your needs. Wish you well....

ltc

My Feedback: (3)

It looks like this design does not use wing struts between top and bottom. Is this true?

The CA Models Andes v1 did not use then
either but their new v2 has put them back in

Is there an advantage to not having them on a biplane?

ini

ltc:
It does have the struts.
They are just not shown in that picture of painted result. OTOH that picture doesn't include landing gear either.

About the plane and build quality I can just state just photos are not doing justice to the level of quality.
The plane is a remarkable improvement to previous planes Lassi was flying. Especially in integrated rolls and knife edge flying.

ltc

My Feedback: (3)

Thank you
It looks to be very nicely designed and built and the price seems reasonable for the quality, especially if compared to an Oxai / Hui Yang F3A plane.

I just saw the additional photos on the website.
The pull pull elevator I assume is to save weight?
Never having tried one of these it looks like it might be more difficult to setup and match each side compared to a 2 servo elevator / stab or the Akiba style flying stab?

ted32776

ITC, I looked hard at the pull/pull application. One of my Sebart models came with it and I was skeptical at first. Of course, I've heard it's been used in pattern off and on for many years but with today's servos, it became very interesting to see Lassi do this on one of his earlier Sensation[?] bipes.
I had wondered if Bruckmann had used it on his ultra lightweight Pandora. Even though it touts Hitec sponsor decals, I wouldn't have thought they had a servo within his needs for that level of model. Photos don't show much in the tail so perhaps someone here can enlighten me. I asked a pattern friend in Japan but they apparently don't think much of the system today. The advantages are there but I've wondered if it's worth the effort and mainenance.

ltc

My Feedback: (3)

Besides lack of weight in the tail (which helps CG I suppose) what are the other advantages to a pull pull elevator?

I know the Mriya F3A biplane could be ordered with a bellcrank elevator arrangement (or conventional 2 servo) which is a bit heavier than a pull pull bit lighter than a 2 servo tail

ini

Elevator setup by pull-pull or servos in tail is a matter of personal preference.

IIRC Lassi is preferring pull-pull elevator because of easiness in setup and amount (lack) of maintenance. Also stability of elevator trim is leaning towards pull-pull.
However, everybody is not sharing this opinion (myself included).
Glacial is setup so that both ways are possible. In one of the photos above you can see a paper tube for servo cables going to tail. A bellcrank elevator can also be built if desired. You need to build it yourself though.

ted32776

Thanks INI. Great input. I had communicated with the gentleman who makes the Mriya last year and he indicated he thought his belcrank unit came originally from Japan [months later, I actually stumbled across it on an obscure Japanese website]. He frankly said it was not an "ideal solution". I later built my own from CF along with CF pushrods and BB links, it worked well but in retrospect, it just seems ridiculous now that servos like the MKS 69HV have come along. It's interesting that Lassi prefers it's "easiness of setup and amount [lack] of maintenance, seems to be opposite of what I would think but I'm not at his level. Good information none the less. Still would be interested in any insight into the doings of Mr. Bruckmann in this area. He is one impressive modeler for sure.

ini

Actually, quite many of us are using pull-pull rudder. Elevator has two halves, so it is double work compared to that.
The worst part of installing pull-pull system is finding the right location for wire exit hole. The rest is a breeze and less work than fabricating push rods.
My concern is the ability to remove stabs for storage and transport. I need to remove them occasionally and prefer servos in stabs. Seeing others remove wires, that doesn't seem to be an issue either.
IMO, bellcrank elevator is the most complicated solution and not worth the effort. It sure looks neat and eliminates the need of stab incident adjusters. Still don't like it because of extra work required in setup.
Unfortunately I do not have any knowledge of Mr. Bruckmann's plane nor details. Interesting approach he has at least.

ted32776

Of course, I have many with rudder pull/pull, but it was the elevator that was of interest here. Agreed, stab removal becomes a pain, especially with BB links. As best I can tell from pix, the Pandora seems to be all internal within the fuz. Not certain, just looks that way from the angles of pix available. Perhaps some of the thousands reading our posts will reply........LOL.

papaone

Hello

Just my opinion,
I think the advantage is to concentrate the masses closer to the CG, to reduce the rear inertia and consequently to have better snap.
Claude

ltc

My Feedback: (3)

Would reducing elevator servo mass in the tail make that much of a difference given the far larger fixed mass of the motor/batteries up in the very front?

ini

^Yes it would
The formula goes I = mr^2
I is monent of inertia, m is mass, r is distance from rotation center.
So, the added weight does matter, even if it so tiny.
Reducing that weight will make the plane more agile.

About earlier thoughts of Bruckmann's Pandora:
The first one seemed to have a full flying stab and the one used in last WC with smaller canalysators seemed to have servos installed in stab. Information is based on photos in his FB wall.

When using fork type pull-pull wire ends detaching the connection is similar effort as unplugging servo cable.
So, pull-pull elevator is actually quite simple to build and use. It just seems to be more work than it is.
When it comes to the top level the changes in elevator trim (when temperature changes) seem to be noticeable with push rods.

ted32776

So, late to the party and all that...... I would imagine someone has resolved the issue of where to locate the fuz holes for each cable[Kevlar or whatever] by using a laser pointer after surface control arms and servo/arm is mounted in front......??????? Also, if yes, does this work on various fuz contructions, ie. glass, wood, etc?

bandicootf16

ini
How does Lassi/you secure the end of the cable. Looks like it is just twisted with heat shrink over the top. I assume it is secured using CA. I have always used a brass/aluminium crimp. Setting the cable length and using a crimp is the bit I find the most fiddly.

ted32776

Not to stray too far from Glacial topic, but here's a very informative debate on various pull/pull methods. Of particular note are the posts from Speedracertrixie, Shaun has some very simple, light ways of dealing with pull/pull that work very well in my experience. Pull-Pull for rudder in 2M planes - recommendations.