DagTheElder

Hi,

Interresting this fiber, but when I Google this it comes up With cloths for cleaning glas,etc. The texture looks like normal fabric. It looks useless for me?????????


Regards

apereira

This is aerospace grade material, you got the wrong thing for sure, it looks like golden brown fiberglass.....

serious power

Hi,
A link to the manufacturer or to a source please !

Brian

apereira

I saw it before it went into production, I will try to find a site, but as the Patent is recent I do not know if it is there.

It is for aircraft interior cabinets, and similar. The cabinet panels on an aircraft are made of panels which are built from a honeycomb core like Nomex and then laminated on both sides, usually fiberglass, now the creators are making them with this material instead of the fiberglass, but I do not think is available to the public, Tuny Pro is a different case as he has the material for testing.

apereira

That sounds about right,

I think in the USA they are all special order now, so, just in shipping the price goes high. But anyway, Oxai has not decided if they will re open.

Thanks Claude

MTK

Brian,

Henry Piorun from Canada, manufactured models of his design back in the late 80's, early 90's. Typical glass fuses with balsa skinned plug in foam wings and stabs. For the schedules we flew then, these models flew very well. 60 2 stroke or 120 4 stroke power.

Not unlike what Bryan Hebert is doing today. Ehh?

Edit.... I looked up Henry Pioruns wing build and it was nicely done. Much the way I did things ten or more years ago. My technique has changed because I wanted to use vacuum for sheeting. The large honeycomb holes don't work well in vacuum, causing skin sag. The result looks like a golf ball (which is not a bad thing, btw).

I treat the socket differently too so there is no need for any spars.
Also the control surface bevels and panel LE's are molded balsa usually, not just sanded slabs of wood, although slabs of wood were used on the last set I built for a customer.

other that, results are very similar. Weight of a 470 square panel comes in at 243 grams ready to cover. A 130 square stab panel comes in at 54 grams ready to cover. Not as light as built up but decent. Looks like Henry got similar weight.

serious power

Hi Matt,
Interesting - thanks, a friend pointed me to that thread.
I may get into why if I get the time later.
The world was a very big and disconnected place just 25 to 30 years ago.
Lots of us were beavering away, more or less oblivious to what others were doing.
Back then the bi-annual highlight was seeing whatever new models the Japanese, the Matts (also Japanese made), and one or two others would bring to the WC's.
Also some interesting stuff from your side of the pond around that time.
Yes Bryan has a lot going on right now.

Brian

DagTheElder

Trying again, what weight of RTF plane will be Your preferance?

How pattern planes behave in air does not improve With fantastic finish. Agree??

Regards

serious power

Hi
Agree, maybe behave better with rough finish !!

Brian

papaone

Hello
Friend of mine just received his Kunzit he ordered directly to Oxai.
Claude

MTK

Dag,

MY preference and most of the folks I fly with, the lighter the better. IF a plane can be made to 4750 grams it will fly easier, better and consume less battery than one at 5000.

If it can be made to 4500, even better. Some people think that light and wind don't mix. In my experience, the lighter plane will damp quicker and actually is capable of flying smoother in wind.

I modified an Xtreme Composites Griffin earlier this year making its weight less than 4500 grams. It flew fantastic at that weight. But it turned out to have a weak fuse. It buckled during a series of snaps and the crash landing destroyed it. Oh well, that's the beauty of a purchased airplane.....little emotional attachment. I moved on quickly.

apereira

Oh, good news then....

Thanks Claude

apereira

In the 2007 WC in Argentina CPLR's father covered Benoits Osmose wings with some kind of paper to make it rough, Christophe had the standard shiny version, they both flew very well, the pretty and the ugly (really ugly finish).

Maybe there are pictures somewhere in the web.

Regards

DagTheElder

To all,
Thank you for Your input re weight RTF With 5000mah battery. I will aim at 4750gr or better for my NeXT build.

Regards

papaone

Hello apereira

You are right.
Christophe changed wings by wings covered with brown paper mad by his father Jacques.
See pics; it is not Osmose's wing, it's just an example.

serious power

Hi Dag,
That would be a very good target. (My original answer to your question was not very clear - sorry)
However (there is always an 'however' ) what is more important is to have light wings and tails. If these are lighter you have much less rotational momentum/inertia when doing rolls, snap roll and spins.
As a result these will all be easier to initiate and to stop. At any given rate of rotation the effect will be two fold ;
- Easier to perform these consistently.
- They will be much more 'crisp' in appearance. At a chosen rate of rotation, fast or slow, the rotation will start and stop more crisply. There are lower inertia levels.

Momentum/inertia are a function of weight, a multiple actually !! So you get a multiple of the weight reduction in reduced momentum.

So build these as light as is possible and consider building them so they get progressively lighter from root to tip. Keep wing servos and links etc inboard and tail servos forward in the fuz.
The wings are most important. Tail weight effects snaps for the most part.
Obviously the lighter all these are the lighter the total.
So there is total weight and distribution of weight to think about.

Brian

bem

My Feedback: (1)

Brian,
What You write makes sense, basically keep as much weight towards plane center of gravity point.
It was little better in the old says regarding this since then we had most servos basically centered in the middle of fuselage and wing servo(s) in middle of wing. And retractable landing gear folding towards center of the plane.
Today we have mini-servos in tail for elevators and often also a standard servo for the rudder in the tail. Aileron servos in wing is often rather long distance from root. All this do not help to get optimal maneouvre capabilities.
I suppose it has to be a compromise. But it is often 100-110 gram back in the tail with 3 servos. To get rid of half of that by moving the rudder servo to center of fuselage would be better as far as weight distribution in the plane is concerned.
With the very high fuselages that exists today the vertical center of gravity is also important to keep track of, for example where to place the flight LiPo battery vertically in the fuselage. I remember I checked that carefully in my previous plane (MythoS Pro) but forgot to check it in my present plane (Galactika).

/Bo

serious power

Hi Bo,
A pull-pull can be used on Rudder and on Elevators.

From the model designs that I've experienced recently I have this rule of thumb re vertical CG ;
- Bipes ; Install equipment and batts,, as high up in the fuz,, as you can.
- Monos ; Install the stuff as low down as you can.
- Large cannaliser ??

Brian

DagTheElder

Hi,
Thanks for advice, but do me and you a favor and take a look at my thread http://www.rcuniverse.com/forum/rc-p...oriz-stab.html

Here you will see that areas and moments are very important if you want a plane that is mix free. The one in my last post does fly without any mix whatsoever. Problem is that i desided to use materials from shelves and drawers With result that it is on the Heavy side. Still legaly weightvice..

See also my FB Dag Řiseth Larsen

Any questions re tables etc on PM please.

Regards

MTK

Nothing wrong with brown paper to cover wings. Paper grocery bags are made from the right weight paper. The finish can be Esaki and dope and paint, and can be made to look the same as Oxias.

if we can only get paper makers to make balsa paper with grain, we'll have something special.

serious power

Hi Dag,
Yes I know the thread.
You say 'but do me and you a favor ,,,,,, '
What relates to this or what am I to look for ??

Brian

MTK

Actually with three servos in the tail, it is closer to 160-170 grams. Don't forget servo mounts, pushrods and the servo cables. They all add....

pull- pull all around adds about 70 grams for all around connections for steel cables (around 45 for Kevlar) and is what I do. But not everyone can do pull- pull as my friend Dave explained recently.

drac1

My Feedback: (4)

I've always used pull/pull on elevator and rudder. It appears that models are becoming nose heavy, as I've had to put the elevator servos in the stabs to get the CG right on my Valiant and Xareltoo.

MTK

Scott, yes true that. Folks have moved the wing back because the composite stabs and rudder are so heavy. Add the extra weight of all those servos back there and you've got a pound in the tail. Then folks complain that they are pushing the weight limit.... Crazy, no?

DagTheElder

Hi Brian,
To have a trim/mix free plane there are certain conditions to be fulfilled. I thought that all tables in my thread were descirbing the following;
(Lift of Wing x distance from CG) + (Lift of Tail x distance from CG)=0

Are most of the models on current market designed With this in engineering terms???? or are they glossy pigs With lipstick???????
Why are there so many threads asking for mix % for this and that?
What kind of Method are used to engineer this planes???
Probably very difficult to answer, but there are one simpel way to check this. Take a look into the fuselage when People are placing the battery and make up Your mind, why there???

I am probably cursing in the Church so do not remind me !!!!!
I am more interested in Tech questions.

Brian, you mentioned canaliser, I tested a canaliser on my models and found abselutely no difference in behavior except for one thing and that was a very "agressive" rudder else nothing.
Anyway

Regards


Ps. Sun is shining somewhere so I am going there for a week or so.