Because this Blog is updated regularly it is a good idea to visit at least once a week so as not to miss anything. If however you are not a regular visitor, please use the archive links, at the bottom of the side bar on the right, to view postings that have moved off the main page. Or type a key word in the search block in the black bar at the top left and click on "SEARCH BLOG" and it will take you to the posting within our Blog. (For instance, type "Jart" and all the post that mention Jart will open) The Label at the bottom of a post can also be used. Click to get all posts with the same label together!
This BLOG is best viewed at a screen resolution of 1024x768. Click here to get instructions on how to adjust your monitor to these settings.



Saturday, May 31, 2008

2008 Nationals ETB

Ok, guys - a little late with these - but better late than never. Finally here are some pictures and the BERG acheivements from the 2008 Nationals from the long weekend beginning of May at ETB.View of the field - Overcast, wet and windy for most of the weekend. Great turnout despite the weatherPiet Rheeders, Evan Shaw, Derek MarusichCollection of models behind the Gazebos - ground sheets used for protection from the rain







BERG was represeted by this happy bunch of modelling maniacs: Piet, Evan and I did us proud taking a fair portion of the prizes - with our Piet flying his mielie off to win the prestigious Victor Ludorum.


My Estrella just before first flight: far too much launch flap + far too much down elevator compensation = exciting launch and rough flightIan Lessam getting ready to launch his SupraEvan with his new Emoyeni







f3B Speed Base A: Peter Eagle flying. All the juniors - Ryan, Jason and Simon helping Evan with the timing.
The ETB field was in excellent condition, the organising committee did a fantastic job but unfortunately the weather just didn't co-operate. We Managed to get some reasonable flying in on the first day, got rained on a little on the second and third day and just had to give up on the last day.

Johan Bruwer in prep time - Volney and Gert looking on.Herman Webber getting switched on.






Windy weather resulted in very challenging conditions for the 2m, F5J and especially the F3K class models.

RES 100 flight lineIdentifying Piet's Elipse for the distance taskF3B scenes: always good fun for serious and not so serious competitors - even had some F3J models having a go.Midrand team in action doing a quick line change
Dion Liebenberg - Speed KingLeft, as big a smile as you'll ever get from this guy: Dion with his Crossfire after his blistering 15.9 second speed run. Below, me launching Estrella.

Launching the Estrella - now with all throws adjusted and trimmed - very responsive and fast!
F3K entrants left to right: Lionel Smith, Stephane Duponsel, Mark Stockton, Peter Eagle, Craig Goodrum, Rudi King, Conrad Klintworth and Alan SmithBackground: F3K models hovering in the stiff breeze. Top inset: Alan Smith catching. Lower left inset: Stephane Duponsel it his Obsession and lower right inset: Lionel and Stephane waiting for last man to landA really soggy ETB settingDay four dawned and contestants arrived at a really soggy field. Michelle set up a winch to test the conditions. Her model zoomed into cloud cover! We found a dryish patch of grass upfield to complete F3K and called off the rest of the contest.Well at least someone was enjoying themselves!?!









Prizegiving: Evan got a certificate for F3B CD, Alan Smith F3K champ and I managed third place in 2 meter.
Evan Shaw - F3B CDAlan Smith - F3K ChampionDerek Marusich - 3rd 2M

Piet getting his prizes

And on the left, our club superduperhero, Piet Rheeders: Winner of the prestigious Victor Ludorum trophy:

1st place RES100
2nd place F5J
4th place 2M
10th place F3B
12th place Open Thermal

Got to get you into F3K, Piet.

And sorry Piet, just not enough blog space left to show you receiving all your prizes so I've had to overlay all your pictures :-)

Tuesday, May 27, 2008

Dare to enter "The Dark Side"

The refinement of batteries and brushless motors in recent years makes this element of our hobby , very attractive to RC flyers.
The electric revolution is here to stay, so at some stage we all have to embrace it..serious.
This clean(no oil) eco friendly form of power flying with its low noise really sits sandwiched between the power flyer(IC internal combustion)as it is now known and pure gliding .It is one of the fastest growing aspects of the RC flying hobby.
The repeated comments received about the "dark side" really stem from a lack of knowledge of this whole new world of propulsion ,which can have synergy with our form of silent flying.
I for one have very little knowledge of this (dark art) and listen to the guru's in awe and amazement.
They speak a wierd langauge of er ..cell balancers, watts, kv rating, C rating, li-poly , A123, nimh and watts per dmsq . Makes no sense, at all ,rather mysterious.
The local hobby shops are full of ready to go off the shelf electric powered gliders, and at BERG we see many new pilots comming out to the field with this type of aircraft, these are our future pure glider pilots . We welcome the people who start out flying this way.
They buy the box of tricks but know not what makes it tick. (fly)


So getting my feet wet ,but not actually jumping in I bought a cheap electric setup, the first motor emitted , the "deadly blue smoke" but this after a few very promising flights.
I accept I am an old dog and this is a new trick. Who said ........





I replaced the motor with a small AXI outrunner and have had several more flights with no smoke.

























Recent trips to the slope (Sungazer) really convinced me , on the friday before the event Ken Kearns with his electric "assisted" glider made a one hour flight with several small motor runs of 60 seconds in total , usually in patches when the lift just died. You can see the folding prop of the motor on Kens Skylark(electric).



So project electric no 2 is on the building board,
a 2 mtr rudder elevator sailplane with a fairly hot in-runner motor / folding prop and gearbox

In this photo I have started the fuselage construction and want to make sure the gearbox/motor is going to all fit.






Traditional wing constuction with balsa ribs and cap strips, centre panel complete , tips built together and cut in half later.



In this photo the 2mtr wing is complete and covered with monokote it weighs in at 264grams
If I can keep the fuselage light it should climb well.
Piet I have a strong feeling will also go this route , after borrowing an electric and almost winning the f5j event at the recent SA nationals .He flew Tonies 2mtr Tsotsi , with and E-FLITE 10 brushless motor to good effect



So the dark side will be exposed in a series of steps first the the small electric fun fly, then the electric 2 mtr with a hot in-runner/ gearbox and folding prop combination and finally the big 8kg Ventus with the AXI 4130 pushing the CAM 16x10 prop which will be used initially on the slope to sustain flight when the lift stops.
Really quite simple ..unless we have that dreaded blue smoke again, I now also tend to read the instruction booklets BEFORE I actually connect up anything and read up as much as possible on
mighty internet (which was also a tool of the dark side , American military actually).
On the previous power pod post(dig the P's) Bruce asked about the ESC electronic speed controller , he had one that did not cut off the motor at a predetermined voltage and lost his plane due to radio failure/loss of voltage. This was a problem on the older units , on the Ventus/ Axi I have used the recommended JETI 70 amp opto esc but will power the receiver and servos with their own battery pack.















Dabbling in the dark side????? no not really rather exploring into the leading edge light.
Try learn something new everyday it keeps your brain healthy and exercised.
I will post some pictures if these things actually get of the ground
Cheers for now,
Mike


Wednesday, May 21, 2008

The Electricty is back on.



With the spate of power failures lately , it means I have to carefully schedule my vacumn bagging between (load shedding) but this is different this is load lifting.. a kind of ....when the wind dies inhouse thermal generater, insurance.
I am moving into new territory here so anyone using any ideas, seen here do so at your own risk......sign here..............
.
Time to build a power pod with a serious brushless motor which by all accounts can probably
allow ground take offs, with a decent runway and a dolly with biggish diameter wheels, something we will definately attempt.




A piece of offcut bluefoam sanded into a streamlined shape and cut vertically.Then a piece of plywood was added onto which the foam was glued , this is because the foam will be removed later. Some carbon tows added to the leading edge and some layers of 163gr glass.











The actual model is waxed and masked and the power pod base layed up on it for a perfect fit.

This has to be strong so it is about 10 layers of 163gr glass and 1 layer 200gr carbon.


Note the pod sits above the wing joiner also the centre of gravity.









Motor housing was made by waxing a
cooldrink plastic bottle((or whatever size the motor needs) and wrapping around first some cloth then 2 x layers of UD carbon off cuts and some final layers on the outside , next is some more sanding required to smooth it all.









A plywood insert was made using the bolt hole template supplied with the electric motor.

The three bigger holes are airvents.

It is epoxied and glassed in place. Next is some more .............sanding.







.Next the foam was melted out with thinners and it was sprayed with a 2k white, which made it look rather like it belonged on this white glider...exactly right.
In this view you can see, the air can flow through and cool the interior of the motor , there is also a space aroud it and the back is open, all to assist cooling.
For reasons that soon became apparent it has to be a pusher ,if I use the folding prop, a fixed prop will work on the front I have both so have various experiments to try.
I am not starting with Lipo's... seen to many pictures of planes on fire. So until the technology
starts making sense I will run this motor with several ganged 5 cell ni-cad packs of 4800 mah, this motor has a spec of 16 to 22 cells and about 380 revs per volt (prop dependant)so the magic instruction booklet says.
It only needs to run short bursts to gain height for futher gliding or to start a safe landing approach.














The recently maidened and flown Ventus was built light especially for this reason and will be used as this power pod test bed, no fancy pop up system , just common sense engineering.

If this all proves successful , outlanding off more outrageous slopes will no longer be a problem.
Progress so far, next its wiring it up and some motor test runs
then its off to find some BIG AIR and do some tests.
Regards
Mike
Ps the blog showed 22222 hits when I logged in, that must be a good omen

Sungazer 2008

Check out the article in the latest RC Soaring Digest on the Sungazer , Bill and Bunny who publish this , always do a great job with our submissions.

Monday, May 19, 2008

Emoyeni #3 takes to the Sky.


After a busy few weeks before the Nats , I eventually got some time in to finish my 3.4meter Emoyeni.

(Glen from Durban will be glad to hear this, as I can move on to the next project that involves making a mold), but yesterday (Sunday 18 May) I maiden the Emoyeni , and it is just amazing how easy and true this composite gliders flies.

Other than a ground range problem (resolved by removing the Rx aerial to the outside of the fuse), 15g nose weight and some adjustment to the elevator compensation on the full crow -setting , every flight that I few went well. I have to say that I still have to learn a lot about and getting use to the handling of the glider and lots of fiddling with trim, tow hook and CG settings will follow.

However first prize is to go home after your maiden flights with the plane still in one piece.

Later on Evan came around with his new 3.7 meter Emoyeni and we flew a few flights together.

For our overseas visitors the name Emoyeni, translated from Zulu to English means “Upon the wind”.
The name of the Glider was inspired by the Black Eagles which visit our club from time to time. They nest on the nearby ridge and can often be seen thermalling overhead. The females name is Emoyeni. Check them out at this link to the Black Eagle Project at Roodekrans






The real Emoyeni


EMOYENI"UPON THE WIND"The grand old lady is probably 35-40 years old and is loved by many who have followed her life cycles with passionate interest.The first sightings of Emoyeni were in the early 1970's with her first mate, unfortunately we do not know anything about him. Quatele was her second mate and she scoured the ridges searching for him when he disappeared in 1998. Patiently taught her third mate Thulane everything she knows, tolerating his initial shortcomings, but now appreciating his newfound expertise. Many a lesson could be learn't from this wondrous lady.
Click on the Lable below to see previous posting on the Emoyeni




Thursday, May 15, 2008

BERG Subs

Guys it’s that time of year again that all subs are due by the end of the month so here are the bank details:

Nedbank: Savings acc
Krugersdorp Branch code: 198841
Acc #: 2988514461

Pease put your name in the ref. So i can see who it’s from.