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Author Topic: What is the advantage of an I beam wing?  (Read 7096 times)
Andrew Tinsley
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« on: February 26, 2011, 01:35:02 PM »

Hello all,
  From experience, there is a lot of extra work involved in constructing an I beam wing. Unless it is covered in something like my usual silk over mylar and dope, the structure seems to be very floppy. I have seen a couple of I beamers covered in *cote and they were very flexible! Apart from perhaps some weight saving over conventional construction (D tube etc), are there other advantages that I have missed?

Regards,

Andrew.
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« Reply #1 on: February 26, 2011, 01:53:38 PM »

From what I've gathered,- you've about got it summed up. SN had a great series on I-Beamers by Fred Carnes.
My opinion - the build depends on what you enjoy! If you love building, it's great. If you much prefer flying, not so great  y1
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« Reply #2 on: February 26, 2011, 02:09:02 PM »

I am presently painting my latest I beamer, the Minado. They build fassst, only one rib to cut, 98 times. Just trim each rib from the rear. They look like no other model, just plain beautiful, especially when the sun shines on all those ribs..
They are "floppy" if not covered with silk,  silkspan or polyspan.  Plastic covering will NOT give them the stiffness a wing must have. 
The wing is built square to the fuselge using two tip jigs on the end of the main spar. These jigs become the outer ribs when trimmed away.  Alignment is a no brainer, as everything has to line up to be glued.  Can't glue holes.

If you build one correctly, you will love it/them.  Coffee Hoff y1

So far I have built 14 I beam models.  Some once, some four times.

Bill Little? Ed Ruane?  Comments?
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« Reply #3 on: February 26, 2011, 02:46:35 PM »

Hi Ty,
  I found the build to be quite a slow process compared with a conventional wing. But that's probably because I wasn't too familiar with the construction method. Your point about it being self jigging is one that I completely missed and is a fair point. I am not sure if I feel up to doing it again. I would imagine that even a minor impact with terra firma, would result in major damage compared with a conventional build. However we are not supposed to crash.................er, I mean have a heavy landing with our toy planes! 

Regards,

Andrew.
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« Reply #4 on: February 26, 2011, 02:52:12 PM »

Yeah the building of I-Beamers can get boring when cutting ribs.   But, the fuselage is the first structure that is built and must be built square and true.   The spars must be also be built square and true.  Same for the leading edge and trailing edge.  The tip plates, which usually are the tip rib mus match the fuselage Spar, TE and LE holes.   A good cutting jig helps with the ribs.  Building the stagger wing I cut over a hundred ribs and still had to cut more.  Have to laminate ribs at the fuselage juncture.  As stated each riblet I will call it, has to be trimmed at trailing edge to fit the location.  Do top or bottom depending on design, when done flip over and check alignment.  Put the rest of the riblets on to completion.   Half ribs are a blast and add to more cutting, but with less material.  I myself have one design that I flew several years ago that would have been better as an I-Beamer than what the designer showed.  Right now I have a project to get started on and hope I can do it justice.   Hoff Hoff
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« Reply #5 on: February 26, 2011, 03:01:49 PM »

HI Andrew.  In most conventional models, and I have about 13 in my shop along with 6 I beamers, it is taking me much longer to do the 660 Stiletto compared to say a Tucker 4. My I beamers are built fuselage first then the wing into  and part of the fuselage.  To do the wing entirely seperate, then having to install it into the fuselage takes longer just to align, trim to fit, etc, than aligning the spar then adding a hundred identical easy to do ribs.  I can do the entire wing on an I beamer in about three hours, including the tips and landing gear with time off for a cup of coffee or head run. What I don't like is the covering aspect of an  I beam wing. I prefer to to the entire wing, not just the root.

They are different as is a foam wing or a millinieum wing or a lost foam wing ( a take off of an I-beam when you look at it).  Speed and light weight are the two biggest points in favor of an I beam, but over 700 sqaure inches, they tend to get wiggly and this may be why most are in the 550 to 600 range. Most, not all.

Like many things, it's a matter of experience and or taste. Hoff
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« Reply #6 on: February 26, 2011, 03:09:41 PM »

Doc, every rib is identical. How can that be hard. As to boring, I cut mine during comercials if watching TV, which more and more, sucks big time.  I count the ribs required, get the proper wood, new blades for my jig, and cut 20 more than needed, as I always seem to break one or two, just like a laser cut ribs can get broken. It happens,  I plan for it...
All parts must be true on any stunter, spars, LE TE, fuselage sides, ribs, formers, so the I beamer is no different and in fact some use less parts except for the number of ribs, which are all identical. Hoff
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« Reply #7 on: February 26, 2011, 03:26:48 PM »

See my 11 day Ares here on SH. I beam is the easyest wing to build and in perfict alignment. Thats 11 days from first piece of wood cut to in the air and it aint no slouch airplane.
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« Reply #8 on: February 26, 2011, 04:38:02 PM »

Because they look so cool.
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« Reply #9 on: February 26, 2011, 05:34:20 PM »

Well,

Lets see now,  The Bad News was an I beamer and it sported nearly 700 Sq Inches I believe.  I beamers do look very cool, and Ty are you going to paint your Minado like either of the two that Tom Lay had ahold of?  Minado = pretiest plane ever to grace a control line circle!

Jim Pollock   Hoff
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« Reply #10 on: February 26, 2011, 06:32:45 PM »

I have found the bodies to be much stronger than conventional bodies because there is no big cut out for the wing. Less vibration,much stronger nose.
Ed
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« Reply #11 on: February 26, 2011, 07:03:39 PM »

Well, I don't know about the structural benefits but you gain the respect and admiration of people like me who are waaaaayyyyy too lazy to ever build a wing with that many rib bones. Smiley Smiley Smiley Smiley Smiley

-Chris
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« Reply #12 on: February 26, 2011, 08:16:39 PM »

I find them very easy to build. Especially if you use a jig for cutting the ribs. And besides, they look cool.
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« Reply #13 on: February 26, 2011, 08:32:11 PM »

Don't use your best contest balsa for the ribs.  I have done so and spent more time repairing ribs I had broken than putting in new ribs.  Repair of an I beam is quite easy.  You just replace the broken ribs with new ribs and recover. 
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« Reply #14 on: February 26, 2011, 08:38:50 PM »

So true about the wood for ribs.  I think that is why 1/8 sheet balsa is used in mine.   Hoff
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« Reply #15 on: February 26, 2011, 08:47:24 PM »

' Bend like a willow , my son '  ? With spruce cap strips ,
 you can put the fuselage over your knee , covered with
silk, you can maybe get two in deflection at the tips ,
(rather carefully) if youve used good hard wood for the spar.

More than ' good hard ' timbers , its timber selected for Good Grain,
no knots , whorls etc. SO , you dont need all this fancy 4 - 6 Lb
unobtainium. The ribs being only about 1/4 in deep (7mm is good)
to build a strong plane at a sane weight .

The Folkerts I built used all 7 to 11 Lb wood , softest for fuse sides
though its an oval Fuse. tissued and doped . about 57 Oz. for 700
Sq. In.Handles rough air / wind really well.

Has had 4 hits from brain fade, two cuts at top of wing over, run like stink
and get lines tight to turn as ' contact' is made.though the shock from the
'grab' on the lines I believe removes much inertia. A wing over take off from
 a stooge up hill into wind in a farm paddock, soft ground.pulled it out , hosed
the intake out and tried again.
A torque induced ' come in ' inverted on a rich run , clowning.When shed come
over the top lines loose swinging upright and I hit full down as they tightened,
and a inverted hit in bunts in wind pulling down over five of em when I wasnt
paying attention ( to the plane ! )
And , the worst damadge , hurrying out of the shed and getting the tailplane
 caught between the knees , spliting one side of the fuse under it .

was glued together with Great planes Aliphatic and ' a few ' ply doublers with aryldite .

Hence " you dont need 4 - 6 Lb wood "    mad-wife
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« Reply #16 on: February 26, 2011, 09:23:15 PM »

It wouldn't hurt to cover both sides of the rib stock with tissue paper to strengthen the sliced ribs and reduce the breakage during construction.

Aside from the flexibility issue (very big IMO, but carbon fiber added to the spar and TE would help a bunch), I would be most concerned with fitting the ribs to contact/fit the spar. Notching the ribs,  planing down the spar caps, or filling gaps with small bits of balsa.... drink Steve

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« Reply #17 on: February 26, 2011, 09:40:31 PM »

Anyone with building concerns should watch Werwage's I-Beam video, available from Bob Hunt. You'll see what fast building really is. I imagine Robert and Ty have this down well.

SK
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« Reply #18 on: February 26, 2011, 10:08:19 PM »

Well, Ty asked for a comment from Ed or me, and Ed has answered! LOL!!

I find them to be the fastest building models (overall), and I have FUN building them!  Once the wing is done, that is about it!  Cutting the ribs takes a while, but cutting any "ribs" takes a while (unless you buy laser cut Grin ).  I have made a "jig" to cut them, and used just plain old plywood templates and done them that way, doesn't matter.  (I must be doing "something wrong", because I don't really break many, if any, ribs when I'm building one. Huh )  Properly sheeting a foam wing takes a while, cutting lost foam ribs takes a while, stack sanding ribs takes a while......  But once the ribs are cut for an I-Beam, gluing them into the wing goes REAL fast.  There have been three people come to my house with plans and a stack of balsa on Friday afternoon, and left Sunday afternoon (two days later) with a framed up USA-1.  That's the fuselage and wing built.  No "all nighters", regular meals eaten, just two nights sleep and two days working. (well Bob Lampione actually stayed longer, but his USA-1 was almost completely done!! LOL!!)  30 minute Epoxy, for the doublers and Motor Mounts, and CA glue is FAST!  And alignment, as mentioned, is dead on, has to be!  And easier (to me) than any other means of joining a wing to a fuselage and having it true, with a lot less alignment work.  And like Ed said, the fuselages seem to be stronger.

Probably the best flying model I have ever had was a USA-1 (700 sq. in. plus, I hear).  It came in at 54 oz. RTF.  And it looked pretty decent to as far as the finish goes. 

An I-beamer, to me, has no "Down Side", and I have built more I-Beam models over the years than any other type.

"Bill"
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« Reply #19 on: February 27, 2011, 10:16:46 AM »

Well,

Lets see now,  The Bad News was an I beamer and it sported nearly 700 Sq Inches I believe.  I beamers do look very cool, and Ty are you going to paint your Minado like either of the two that Tom Lay had ahold of?  Minado = pretiest plane ever to grace a control line circle!

Jim Pollock   Hoff
For the record, I did say most are under 700 sq inches. Most, not all.  I have the Minado painted, but not exactly like the metallic purple one. Yesterday I applied the first coat of SIG Lite clear. More today.
While all this is going on I have a new I beamer, called the Phoenix. It was designed by a gent in Ohio. I forget his name at the moment, but it is on the plans.  Very much like a Super Ares, but with squared tips and two rudders on the stab.
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« Reply #20 on: March 02, 2011, 08:53:48 PM »


Lets see now,  The Bad News was an I beamer and it sported nearly 700 Sq Inches I believe. 
Jim Pollock   Hoff
[/quote]

Wow.  Did someone build one I didn't see? 
None of my Bad News planes were I beamers...Well, none that anyone saw for any length of time.
The ONE Bad News that was an I-Beam never saw a contest. The handle cable broke, and it didn't survive its encounter with the asphalt.
However, the carbon spar in that wing survived and eventually won the World Champs...Should have called it the Phoenix...

Paul W
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« Reply #21 on: March 02, 2011, 09:25:40 PM »

I remember the Reno Bad News.
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« Reply #22 on: March 03, 2011, 05:28:30 AM »

Thanks Guys,
  Your responses have been quite enlightening. The suggestions of covering the (not too light) sheet with tissue was a really good tip. I used light wood and had some problems with splitting. The plane I built was a take apart one and I now realise that one of the main advantages of an I beamer was lost! Funny how the brain never clicked the light bulb on that one!
  I did use an aluminium jig to cut the ribs (maybe not the correct term, riblets are part ribs between the LE and spar in my terminology?). Maybe I was a bit slow on cutting the ribs for fear of splitting. Using doped silk over mylar was a Revelation as to increasing the rigidity of the structure. It brought back memories of tissue covered lightweight free flighters from my youth!
  A query about the mention of cap strips for the ribs. None were shown on my plan and I think someone mentioned that the cap strips should be hardwood (spruce?). Is this normal for an I beamer? Secondly the I beam itself was shown as balsa, again should this be something like spruce? If so, the I beam concept seems to be a lot stronger than the wing that I built!

Thanks again,

Andrew.
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« Reply #23 on: March 03, 2011, 09:41:01 AM »

No cap strips on the ribs.  The balsa spar has caps on it top and bottome.  Plywood laminate in the central part of the spar.   Hoff
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« Reply #24 on: March 03, 2011, 10:25:46 AM »

Guys
I have been looking at alternative construction for an I-beamer.  One of the two things I was wondering about was:
- instead of a I beam spar a box C/F top and bottom?
- 1/16" cap strips on the ribs (classic I-beam ribs)?

Norm
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« Reply #25 on: March 03, 2011, 11:19:19 AM »

Anyone built a I Beamer and had a bad experience carving the leading edge?   Hugh
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« Reply #26 on: March 03, 2011, 02:21:12 PM »

Guys
I have been looking at alternative construction for an I-beamer.  One of the two things I was wondering about was:
- instead of a I beam spar a box C/F top and bottom?
- 1/16" cap strips on the ribs (classic I-beam ribs)?

Norm


I think Paul built a Impact like that
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« Reply #27 on: March 03, 2011, 02:35:58 PM »

Anyone built a I Beamer and had a bad experience carving the leading edge?   Hugh

I've never "carved" a LE on an I beamer. Just sand it to shape, and not much there to sand anyway. Hoff
However (bet you knew that was coming) I am at present, building an I beamer with a three piece LE, laminated, that will give a larger radius to the LE and it will planed, not carved, to shape, Much safer. When I carve, the term "butcher" comes to mind. Layingdown
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« Reply #28 on: March 03, 2011, 03:37:08 PM »

Guys
I have been looking at alternative construction for an I-beamer.  One of the two things I was wondering about was:
- instead of a I beam spar a box C/F top and bottom?
- 1/16" cap strips on the ribs (classic I-beam ribs)?

Norm


HI Norm,

A well designed CF boxed I-Beam would definitely be stiffer than a balsa one (unless 40 lb balsa was used! LOL!!).  I am sure Paul has done a CF beam, IIRC, a molded one but I don't remember the exact process he told me.. Huh  Hopefully he will chime in, or just contact him directly.

I have found that sandwiching the .007 CF strip between the spar and cap strips does add a good bit, along with facing the TE with the same.

Any particular thought behind cap strips on the ribs?

Bill
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« Reply #29 on: March 03, 2011, 04:13:22 PM »

As to a box beam, I believe a kit was put out by Bill Sawyer that had something like that or two parallel I- beams. Either his Playboy or Continental as I heard it.  Was also told the beam was on the heavy side.   Coffee
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« Reply #30 on: March 03, 2011, 05:39:52 PM »

Lets see now,  The Bad News was an I beamer and it sported nearly 700 Sq Inches I believe. 
Jim Pollock   Hoff


Wow.  Did someone build one I didn't see? 
None of my Bad News planes were I beamers...Well, none that anyone saw for any length of time.
The ONE Bad News that was an I-Beam never saw a contest. The handle cable broke, and it didn't survive its encounter with the asphalt.
However, the carbon spar in that wing survived and eventually won the World Champs...Should have called it the Phoenix...

Paul W

And after that Paul invented the hard point handle.

Ted
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« Reply #31 on: March 03, 2011, 06:49:53 PM »

And after that Paul invented the hard point handle.

Ted


LOL  Ted  ,  Paul  didn;t invent the  HP handle, I have used them for 30 years now, You could buy Tatone , and other brand hard point handles back in the 70s
others made their own too. I have 4 or so here that I used for many decades

regards
Randy
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« Reply #32 on: March 03, 2011, 08:20:02 PM »

Dave Merithew in Binghamton NY was building adjustable Hard Point handles in the early 60's. I still have one of the handles. I am still using muflers he made for my first ST/46 back in 1968.
Ed
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« Reply #33 on: March 04, 2011, 01:54:48 PM »

Get the best of both worlds.  Get a set of laser cut ribs for your favorite design.  Build up an I-beam style fuselage and run the bottom spar through the fuselage.  Jig up all the ribs and trailing edge.  Add the sheeting, with a narrow strip of sheeting between the first two ribs.  Turn it over and do the bottom sheeting and capstrips.

Not having a big cut out in the fuselage makes for a much stiffer, stronger, lighter plane.
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« Reply #34 on: March 08, 2011, 10:52:45 AM »

Hello all,
  From experience, there is a lot of extra work involved in constructing an I beam wing. Unless it is covered in something like my usual silk over mylar and dope, the structure seems to be very floppy. I have seen a couple of I beamers covered in *cote and they were very flexible! Apart from perhaps some weight saving over conventional construction (D tube etc), are there other advantages that I have missed?

Regards,

Andrew.

Andrew,
Real reason in my opinion is because they look exotic and beautiful.
However, about 15 years ago I wondered the same thing and with access to a good CAD system at the time proceeded to calculate the weight of all components in both an I-beam wing and a C-tube of the same size (650 Sq In.)   Wood density was selected for the best structural integrity of each separate wing construction process and not just calculated on the same densities.
Covering material and five coats of clear dope were included in both calculations.  Identical control systems were used. Covering material was SGM Silkspan.
Unfortunately I can't find the file with the actual weights for the two wings, but can definitely remember the outcome.
The I-Beam wing was 16% lighter.
When a finite element analysis (1st order only), was performed on both as one would expect the C-tube wing was much stiffer in torsion.  This does not mean that the I-beamer was not stiff enough just that the C-tube construction was stiffer.
So...there you have it!

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« Reply #35 on: March 08, 2011, 06:02:18 PM »

Advantage to the I-Beam? I'd say look back to the source.

The I-beam structure has its roots back in Detroit and the Strathmoor model club, which met in the basement of the Parks & Recreation building.  The club was primarily Junior & Senior aged kids mentored by a handful of caring adults.  I believe in that atmosphere the classic 50" span I-Beam stunter came about as a result of:

* Easy to scratch build = lower costs versus a kit.
* Built fast - kept kids attention spans focused
* Economical - with almost no wasted wood any kid with a paper route could afford one
* Did not need PERFECT wood - even "medium" wood was usable - and easier to handle too.
* Easy to repair - 1 rib fits all!

Their models performed; the performance of those kids is written into our event's history.

Sadly I think a lot of the OTHER I-beams were lost forever; combat models (I-beams built fast and lent themselves t mass production), and sport models models like Rod Pharis' Berkley profile (Lancer? Interceptor?) which used the I-beam structure.

I only got around to building a couple I-beams in the last few years.  Both are covered in Monocote and both are very stiff and strong - I do not think folks are giving 'cote enough credit for what it can do.  To me, 'cote represented that last piece of the puzzle - a light durable covering for all those ribs!
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« Reply #36 on: March 08, 2011, 09:51:19 PM »

Advantage to the I-Beam? I'd say look back to the source.


I only got around to building a couple I-beams in the last few years.  Both are covered in Monocote and both are very stiff and strong - I do not think folks are giving 'cote enough credit for what it can do.  To me, 'cote represented that last piece of the puzzle - a light durable covering for all those ribs!


Dennis;

Far be it from me to question your experience, just mine was different, and it could have been my building technique.  Bottom line was my Monocoated I-Beam wings just flexed too much and eventually failed, some sooner than others.  Those covered with silkspan lasted as long as they didn't deaccelerate too quickly from contact with the ground.  And, some of the wings I built were actually fabricated outside of the fuselage using support blocks for the LE and TE so that I could build a straight wing flat on the table with a sheeted center section.  As you mentioned, I-Beam wings were very economical on balsa usage (and I was a kid with a Maine rural paper route of 30-40 customers spread over 6 miles, so every dime counted).  I Monocoated a couple of them when time was short and I had some lawn cutting money in my pocket, and noticed a huge difference in wing flex, especially during high winds.  All failed prematurely.  Those that were silked or silkspanned lasted until I failed and put the plane into the ground.  Bottom line was the doped silk/silkspan took the tension load with less stretch than Monocoat, even though it was not as puncture resistant.  Monocoat was and is tough, but it does stretch a little when under load.  On a true I-Beam, stretch allows flex, and flex induces failure - at least it did in my case (your mileage may vary). 

Perhaps just a different point of reference.

There are few sights with model airplanes that have the understated beauty of an I-Beam wing ship that is graced with near flawless construction and dyed silk or silkspan on a late summer afternoon with the sun shining through the wing as it goes through the pattern.  The overused word "transcendental" comes to mind.   

That being said, I plan on using Ed Ruane's modified Warren Truss I-Beam rib system one of these days.  Perhaps it will reduce flex enough for me that Monocoat will work.

V/r

Bob Kruger

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« Reply #37 on: March 08, 2011, 09:55:09 PM »

Randy,

Ref.  "And after that Paul invented the hard point handle."

Ted was pulling everyone's leg. You took the bait hook, line. and sinker"
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« Reply #38 on: March 08, 2011, 10:09:50 PM »

Randy,

Ref.  "And after that Paul invented the hard point handle."

Ted was pulling everyone's leg. You took the bait hook, line. and sinker"


 

Ted
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« Reply #39 on: March 08, 2011, 11:36:53 PM »

Randy,

Ref.  "And after that Paul invented the hard point handle."

Ted was pulling everyone's leg. You took the bait hook, line. and sinker"


hmm  if you say so, none knew that  I guess Ted may have to xplain  the point in that to me some day?Huh

"And after that Paul invented the hard point handle.

Ted"
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« Reply #40 on: March 08, 2011, 11:39:21 PM »

By the way ..... Ted.....   did you see  the round handle  that PJs  Dad  is using to fly in the Bulldog thread?  it would work perfect  with someones  round bellcrank.
I have both  here :-)

Randy
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« Reply #41 on: March 09, 2011, 08:36:02 AM »

The trouble I have seen with Monokote is people don't use enough heat to shrink it.  I have even seen D-tube wings flex a little bit.  Even the old Ringmaster, Firecat and CLowns will flex if the Monokote is not stretched drum tight.  My experience. Hoff
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« Reply #42 on: March 09, 2011, 09:26:25 AM »

Hello all,
  From experience, there is a lot of extra work involved in constructing an I beam wing. Unless it is covered in something like my usual silk over mylar and dope, the structure seems to be very floppy. I have seen a couple of I beamers covered in *cote and they were very flexible! Apart from perhaps some weight saving over conventional construction (D tube etc), are there other advantages that I have missed?

Regards,

Andrew.

There was a design here in the UK called Thrift - one of the main reasons given for the ibeam wing was economy - yo can get more ribs out of a sheet of balsa than conventional ribs....

Annette
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« Reply #43 on: March 09, 2011, 11:56:11 AM »

Hi Annette,
  That is very true, it tends to be forgotten after cutting what seems the thousandth rib (riblet?)! I got very irritated with the number of split ribs during cutting, at least I used some CA against my better judgement. If you have a cutting template then the cutting gets quicker and quicker until you start splitting the wood. I finished up going slow to avoid it.

Regards,

Andrew.
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« Reply #44 on: March 09, 2011, 02:29:01 PM »

Andrew I know your original question dealt with I Beamers but one alternative you might look at is the Millennium wing.  Very Light and Very Straight.  Now, some people like that "Starved Horse" look with all the ribs showing and you do not get that with the Millennium wing.  But you do get a really strong light wing.  I completely sheet mine.

Mike
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« Reply #45 on: March 09, 2011, 05:34:25 PM »

The trouble I have seen with Monokote is people don't use enough heat to shrink it.  I have even seen D-tube wings flex a little bit.  Even the old Ringmaster, Firecat and CLowns will flex if the Monokote is not stretched drum tight.  My experience. Hoff

Doc;

That could be, although you don't want too much tension or shrink lest you crush or deform the ribs - and that is easy with a conventional I-Beam wing.  I've used enough heat to damage Monocoat in getting it as taut as possible., but I do not claim to be anything more than an experienced amateur in its application.

While Monocoat has gone up in price over the past 35 or so years that I have used it, its still much more economical than a doped finish, especially with the price of butyrate these days (and I use either Certified Coatings or Randolph's that I buy from Aircraft Spruce and Supply).  It makes the cost difference with the balsa at best a moot point, and in a worst case scenario false economy.  Big difference from when I was a kid when I would ride my bike 12 miles one way to the Portland, Maine airport and, if I brought my gallon can, could buy a gallon of clear Randolph's for $4.50 from a local supplier out of a drum.  That would last me an entire summer and then some.

Don't get me wrong.  For those of us duffers who hate to spend a lot of time finishing, Monocoat is a blessing.  For me, it has just not worked well on classic I-Beam wings all by itself. 

V/r

Bob
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« Reply #46 on: March 10, 2011, 03:59:40 AM »

Hi Mike,
  Thanks for your suggestion of the millenium wing. The snag is I do not have a clue as to how you build one! I must start doing a search and working out how it is constructed! Seems as if the learning process is always continuing and no bad thing too. Thank you Stunthanger for the impetus in my education.

Regards,

Andrew.
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« Reply #47 on: March 10, 2011, 09:23:15 AM »

HI All,

I would never even attempt to contradict Denny Adamisin! He's above and beyond my level in this hobby/sport.  His knowledge and experience (and Dave's) eclipses mine by light years.  Having said that, I base all my I-Beam, knowledge on the thoughts and work of  a certain Mr. William Werwage.  He's built a couple in his day.  His words to me were to NEVER use Monocoat on an I-Beam model.  It flexes too much and will fail.  Our "most flown" model has possibly been Aaron's Ares.  Probably as many flights over the years as any model we have had.  The wing has never failed and is as good today as it was over 15 years ago when built.  I have seen I-Beam wings with monocoat fail.  That's a "no brainer" in my book.  No offense to anyone intended.

Big Bear
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