Max Bee wing

[Matt Piatkowski]

Hello,
I am toying with the idea of building the Max Bee wing using balsa ribs.
I have the plans based on original Igor's Max Bee (two *.pdf drawings) showing the root and tip ribs templates used for hollowing the foam core by the hot wire method and can use these templates to create the templates for the balsa root and tip ribs by hand, sketching on Mylar.

Now...the *.pdf drawings were carefully plotted actual size for the scales in inches and millimeters (shown on these drawings ) to be 1:1.
The wings span on paper is 1500 mm. as specified on on the drawings and all other dimensions seem to be ok. In other words: the plotting process did not distort the drawings in a way that can be measured using the metal rulers.

Sketching on Mylar, no matter how careful I am, will introduce errors. Then, I will have to cut the Mylar templates and cut and sand the root and tip ribs.
This process will introduce more errors - they will be small but unavoidable.

The best would be to laser cut all the ribs based on the computer file.

Has anybody tried this for this particular airplane? Is such file available somewhere?

Thank you,
Matt

[KizzieBonnie]

A tough task, huh?)
Even though I can't help you, I wish you good luck with your problem here.
Regards.

[Avaiojet]

Matt,

I actually provide modelers with vector art files that are used for many things. Foam wing cutting, plywood and balsa parts, just to name a few.

And yes, I do airfoils that wind up laser cut.

However, my suggestion would be to purchase the exact foam wing used with the Max Bee design. The wing is an important part of the design, performance and the look.

Foam wings have no sags between the ribs and they look so nice on contemporary designs.

Someone is cutting the Max Bee foam wing. If it was me, and I know it isn't,  I would find out who is cutting them and buy one.

But's that's me. 

What a great looking model the Max Bee is!

Good luck.

CB

[Brett Buck]

I am toying with the idea of building the Max Bee wing using balsa ribs.
I have the plans based on original Igor's Max Bee (two *.pdf drawings) showing the root and tip ribs templates used for hollowing the foam core by the hot wire method and can use these templates to create the templates for the balsa root and tip ribs by hand, sketching on Mylar.

Now...the *.pdf drawings were carefully plotted actual size for the scales in inches and millimeters (shown on these drawings ) to be 1:1.
The wings span on paper is 1500 mm. as specified on on the drawings and all other dimensions seem to be ok. In other words: the plotting process did not distort the drawings in a way that can be measured using the metal rulers.

Sketching on Mylar, no matter how careful I am, will introduce errors. Then, I will have to cut the Mylar templates and cut and sand the root and tip ribs.
This process will introduce more errors - they will be small but unavoidable.

   Small, unavoidable - and irrelevant. You are already changing the wing from foam to built-up, which is going to have MASSIVELY more effect on the performance than a few hundredths of an inch difference in the airfoil shape, just due to the different mass properties and flexible properties.

     Not to mention that even with foam, when you cut it, there are easily a few hundreths variation in the shape, then you sheet it, you sand it, you paint it, and that's good for at least a few hundreths here and there. Change it to built-up, presumably a D-tube with open bay section in the rear, now the sheeting sags between the ribs, the covering sags between the capstrips, the ribs themselves flex to a different shape (particularly with the Max Bee shape, with substantial curvature in that area). If the hot wire is a little hotter today, there goes .01 due to a slightly bigger wire kerf.

    The airfoil shape doesn't matter too much aside from making it fit the cutout in the fuselage, and it certainly will get swamped by the other changes. Make it as close as you can and don't worry about it.

     Brett

[Brent Williams]

You could email Igor Burger, as he may have rib files available.

Bob Hunt makes foam wings for the Max Bee.  I am sure he could make a lost foam setup for you.

Also, RSM has the Igor Burger designed, Ground Fault 25 sized profile which has a built up wing.  It uses the same style airfoil.  Eric Rule could probably do the cad work to scale the ribs to your needs.  

[James Mills]

Lost foam jig from Bob would be a great approach.  He could also probably do a built up, fully sheeted wing jig.

James

[Matt Piatkowski]

Guys,
I have already decided to build the balsa wings using the metal wing jig brackets from James Lee and my own little extras.
The wing will be build using the Tom Morris method, described in Stunt news from May/Jun. 1997 and Jan/Feb 2000.

I may use the CAD generated geometry to cut the individual ribs using laser or CNC router or, if the preparation of the CAD file is too time consuming, I may sand the ribs by hand ( Brett...I hear you). There will be 12-13 ribs for the inner wing and 12-13 for the outer. The wing will be 75% balsa skinned, with four or five open bays.
The entire wing will be covered with Polyspan or Doculam as they provide the additional torsional and bending stiffness. Tips will be thin balsa shells.

I have not decided yet regarding painting but I will select the lightest possible method giving a reasonably decent look.   

Bellcrank and other elements of the control system will be accessible for adjustment and maintenance after the model is finished. 

Take apart design is an option and I am weighting the pros and cons of it in my case. Max Bee has a very long fuselage and, with 59" wings, may not fit the space available in my Subaru CrossTrek. I will probably build the 3D crude shape of the plane using cardboard and duct tape only to check if it goes in.

Concern: I hear from different sources that this plane, being the top competition flier, is somewhat "temperamental": very sensitive for the input in certain maneuvers and, in general, a bit unforgiving. This, I understand, is to be expected from the Formula I design that performs extremely well when the pilot/driver is also very good. My concern is regarding time needed to learn to fly this thing reasonably well after the trimming is finished. Is it 20 flights or perhaps 1,000 flights?
In other words: can the average club flier like myself enjoy flying Max Bee or it will be fighting the race car trying not to crash flying level.

Your comments and suggestions are always appreciated.

"Learning never stops and when it stops this means you are dead"

Regards,
M
               

[Kim Doherty]

Matt,

I wanted to respond to your post because I truly would like to see you get the most enjoyment out of your efforts to fly control line aerobatic models.  As you know I have offered on more than one occasion to help you both improve your flying and give advice on the construction of your models. This has occurred over an almost three year span. You have never taken me up on the offer. (certainly your choice) (I live very close to Matt)

IMHO

I realize that this may come across as sounding a bit harsh but it is presented with more than a bit of understanding of what you need to do to get to where you wish to travel to.
You are no “spring chicken” and your body is not getting “better” as time passes. You are using a lot of time chasing rainbows (which I fully concede is your right to do). At best, you are a good “Intermediate” to entry-level “Advanced” flyer. No shame in that, it is what it is.

So here are some thoughts for you:

-   You ARE going to crash if you want to get better (and not just once or twice)
-   Great models are generally easy to fly for the person that developed them.
-   You need to fly A LOT more than you do just to keep pace with your aging body.
-   You need to fly A LOT MORE THAN THAT if you want to improve.
-   Listen to those that have more experience and leverage that information
-   Building a World Class Model is “usually” the result of first being a World Class Flyer
-   Building  an Igor Max Bee is not a bad idea but reflect on the first point in this paragraph a bit
-   If you do build a Max Bee you will not know if you got it right. Not enough experience.
-   If you did “Get it right” you may not be able to use the advanced performance capabilities.
-   If you modify a Max Bee in ANY WAY! (at all) It will not likely fly like a Max Bee.
-   Igor has MASSIVE amounts of World Class experience!! (Talent is so depressing!!)
-   If you do build a Max Bee use a foam core just like Igor did and have it cut by Mr. Hunt.
-   If you do build a Max Bee you should use Igor’s Expo Bell crank (complexity!)
-   NO ONE at the top level “goes it alone” they all seek help and listen carefully!
-   “Flying” a good, existing, simple, proven design well, will give you a lot of satisfaction.
-   There is no model that is ready to go in “20” flights
-    Talent, Technology and Preparation are equal partners in this journey.
-   Flying a proven design NOW does not prohibit adventures in model engineering later.

Finally:

-   Building three Fancherized Twisters and learning to fully trim them will net a larger payoff.

Always ready to help,

Kim.

[Matt Piatkowski]

Hi Kim,
Come one day to Centennial around 6:30 AM. to see me flying my eParrot and other birds I built.
I normally know if the weather is flyable next morning around 10 PM. the previous day and distribute the flight plan to all the colleagues from the Balsa Beavers Club.
After flying ( I usually fly five patterns with eParrot and one or two with other planes) I will listen to your comments regarding my pattern skills.

Thank you for suggestions and opinions.
Regards,
Matt

[Brett Buck]

\
Concern: I hear from different sources that this plane, being the top competition flier, is somewhat "temperamental": very sensitive for the input in certain maneuvers and, in general, a bit unforgiving. This, I understand, is to be expected from the Formula I design that performs extremely well when the pilot/driver is also very good.

    Good top competition airplanes, when built, powered, and trimmed properly,  are generally *very easy* to fly, easier than almost any other stunt models, and far easier than most trainers (which are frequently dreadful, particular when using vintage slag engines like the Fox/McCoy, etc). I have flown *many* of the top competition models, maybe more different examples than most people.

    That being said "when built, powered, and trimmed properly" is the catch. These models are typically quite difficult to build to the required accuracy, required expert knowledge in the engine setup, and are usually pretty sensitive to trim. Lots of people can get, say,  an Impact, pretty close, 80% of capability, but that last 20% can be elusive. Based on 20_ years of observation, an Impact may be a bit more sensitive to trim than an Infinity (which was a conscious design goal when I designed it), but just the other day I was on here talking about changing a from an aluminum to a steel prop washer and easily being able to tell the difference.

    I have never even seen a Max Bee up close, but after examining it and the on-line discussions I have had with Igor,  the only thing that is really different about it is that it is designed to be trimmed with what I would consider a radical setup, specifically, lots of static yaw angle. Igor can easily explain his approach and he is certainly capable of evaluating when he has it working correctly. My experience is that nearly no one else who has tried this approach has managed to get it working and keep it working for very long although many have tried.

    Kim is giving you very good advice - stunt excellence is a *journey*, not a *destination*. You (and almost everyone outside The Usual Suspects) would probably do better with a simple model that they can build or trim to it's utmost, even if the ultimate capability might be less than a more complex design. 100% of a 90% design is a lot better than 80% of a 100% design. This is particularly true if you haven't entirely mastered engine setup, and that means a *modern* engine setup that is competitive today, as opposed to a 70's stye approach.

     You have to develop building, trimming, and engine setup skills just like flying skills. In fact, if you divide it up into categories:
judging
building
finishing
trimming
engine setup
flying

 learning to fly at a high level is probably *the easiest* to master! Of course you can't do one without the others (unless you just buy a turn-key system, which defeats the point of the entire event).

     As in an earlier response, you will progress the fastest and learn the most if you start out with simple equipment and optimize it, rather than embark on a massive and complex building project and then find that a tiny mistake or error somewhere (flying, building, or trimming) puts you back to square one.

     Brett

[Brett Buck]

-   There is no model that is ready to go in “20” flights

    This is the one exception I would take to your otherwise exceptionally good advice.  I won the NATs with the airplane is more-or-less the state it flew it's first flight, and won Open on fight #19 and the Walker Trophy on Flight #22. (after flying exactly 5 flights total in the intervening year...). It still flies with essentially the same trim setting is had on the very first flight.


 In fact, my last two airplanes were essentially as good as they ever got more-or-less from the first flying session. The 1997 airplane took about 5 flights because I went conservative on the trim, adding more tipweight than I expected to need, and more noseweight than I expected to need, and it took a few flights to convince myself to remove it. Otherwise, the trim settings I ended up with at the end of the first flying session turned out to be nearly ideal - even when I changed engines from a 40VF to a PA61 and then a RO-Jett 61 (being careful to maintain the same CG). I tried it all over the place around the standard settings and it was as close to permanent as it can ever get. Of course there were day-to-day changes like anything else, and that airplane required tipweight changes depending on the air density.

    The 2006 airplane started out with the same trim settings at the 1997 airplane to the hundreth of an inch and the gram. Aside from an minor engine run problem on the first flight (because crashing the year before bent the needle, so I had to replace it), it was nearly perfect. On the second flight, I could have won the NATs, if it wasn't for the fact that it was still a week away.  The one intentional change I made seems to have solved the issue where the tipweight needed substantial changes based on the air density.

    Brett

[M Spencer]

It would be less decadant , and alow recuts if the mood took you in the middle of the night , 

To say cut LEXAN , or PLY with the Lazer Cut trip , for TEMPLATES > !
Building supplies ( here ) have 40 or 60 thou. hard plasic clear sheet , on a roll ( so needs rolling opposite to get flat )
You need to be pretty careless to notch it , even with a brand new scalpel blade .

Dunno if Alloy Sheet would laser cut ??

Just a thought .

[Matt Piatkowski]

Guys,
I am not aiming at the world championship.
My goal is to fly for fun and we all have different definition of fun.
I will not hang myself if my planes are imperfect by someone else opinion as long as they fly the way I enjoy and I love building and experimenting.

During the last three years I smashed four planes to splinters, learned to fly the pattern on the intermediate level and absorbed tons of interesting and useful things about stunt with ICE and electric motors, mostly from this forum.

I also learned a lot about myself and, who knows, maybe this part is the most important.

I will build Max Bee with electric motor, I will build Tiger Shark with Ro-Jett76, I will build my own design with my old but still kicking Jett60 on pipe, I will build the twin electric semi scale and you know what...they will fly well and I will enjoy every minute of it.

When I will come home after flying, I will kiss my wife, get my rubber boots and help her with tomatoes, beans and flowers. Then, we will drink good wine, eat dinner and go to the club to dance Salsa.

Best Regards,
M





"Learning never stops and when it stops this means you are dead"