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Old Feb 28, 2013, 03:08 AM
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Hello Paul - sorry but my internet disruption prevented me from telling you I hope the motor info is helpful. I really look only to 2 sources when it comes to figuring out what to use on my EP aircraft. I have MotoCalc, which I find useful but sometime not very accurate when I test it with my actual aircraft; & then I look at HURC's actual tests of their motor/ESC/battery/prop combos, & I really find that actually much more useful & relevant, because it's not just theoretical.

And I agree that doing a CG test before completing the model is really a good idea, & I plan on it. Thanks for your input.

Jed
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Old Feb 28, 2013, 08:23 PM
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Jed,

Actual test results are very good to have. I've used several electric power system calculators, and they usually get me close.

Getting close used to be good enough when my power trains were either geared or had belt drives and when each cell was 1.2 volts - I could make adjustments by changing ratios or adding or subtracting cells. With outrunners and lipos you pretty much get one shot.

But there's nothing like that first flight to see how it all works! (And nothing as rewarding).

Paul
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Old Mar 02, 2013, 12:34 AM
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But there's nothing like that first flight to see how it all works! (And nothing as rewarding).
Paul,

When I first started flying electric I really feared that first flight. Then some wise old hand introduced me to a Watt Meter. What a difference that makes - now at least I can know, for my kind of flying, if I have a 7lb airplane when I hook up the meter on the ground I'm looking for at least 700 watts & amps that don't exceed my motor & ESC limits. Since then I really only worry about trim issues on the first flight. I hope the V60 will be no exception.

Jed
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Old Mar 02, 2013, 12:40 PM
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Jed, we're still waiting for you to tell us about the five-bladed wood props on the Spitfire...
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Old Mar 02, 2013, 12:53 PM
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Jed, we're still waiting for you to tell us about the five-bladed wood props on the Spitfire...
Bruce & Dereck - when I received my docent training at our air museum in Palm Springs, where this Spitfire resides, I was told that in the early operations during the war out of very rough & unimproved fields, there were frequent nose overs. With the metal props, the result was usually a broken crankshaft. So the Brits converted to using wooden blades, & then only the prop broke & the plane would be back in service in no time at all. Possibly one of the many brilliant decisions of Sir Hugh Dowding who was C in C of Fighter Command at the time.

Another better known fact about this & I presume all British aircraft, is that the shaft also turns clockwise instead of counterclockwise like ours.

Jed
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Old Mar 02, 2013, 02:58 PM
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Originally Posted by jedorme View Post
Bruce & Dereck - when I received my docent training at our air museum in Palm Springs, where this Spitfire resides, I was told that in the early operations during the war out of very rough & unimproved fields, there were frequent nose overs. With the metal props, the result was usually a broken crankshaft. So the Brits converted to using wooden blades, & then only the prop broke & the plane would be back in service in no time at all. Possibly one of the many brilliant decisions of Sir Hugh Dowding who was C in C of Fighter Command at the time.

Another better known fact about this & I presume all British aircraft, is that the shaft also turns clockwise instead of counterclockwise like ours.

Jed
Unfortunately, my one book on the Spitfire doesn't have much on the props. In the early days of Spitfire service, they were actually fitted with wooden two bladed fixed pitch props. Snag there, the aircraft had to get up to flying speed for the prop to start working decently. So take off runs were very long drawn out affairs. In the early days of the war, variable pitch props started hitting the squadrons and were re-fitted vice the fixed pitch props as fast as they could get them.

You could be right there. What gets done to aircraft in wartime would make the bureaucrats of civilian life go very pale.

The more blades thing was basically to absorb the ever-increasing power of later engines - the Spitfire more than doubled its power over the type's total life history. Even so, there wasn't much space between ground and prop tips when the fuselage was horizontal as take off speed approached. Bragging here some, but Andy Sephton, chief pilot at Old Warden's Shuttleworth Collection and holder of licences for about every single engined WW2 era fighter in England, was an aeromodelling clubmate of mine back in England.

Andy's description of taking off a Griffon engined Spitfire mostly revolved around how carefully you held the pitch attitude during take off, due to the prop tips being something like 6" from the ground with the tail off the ground in take off attitude.

Andy also gave up RC because it wasn't much of a challenge and introduced England to the 9" span scale 'Pistachio' rubber powered class, but that's cute, not relevant

Your docent job at that museum sounds really good. I wish we had a similar museum handier to Chicago than near Champaign, could fancy a gig like that.

And now back to the eagerly awaited V60E...

D
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Old Mar 03, 2013, 02:03 PM
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Venture 60 Build Thread Continued

As promised, I did skip ahead to the “Tail Assembly” section of the manual, & that title in the manual really sums up the essential difference between work on the wing & that which takes place with the tail section. Whereas the former really does amount to taking very disparate pieces of wood & constructing an egg crate assemblage that only begins to look like it might be a wing fairly late in the build activity. However, with the tail group, the appropriate sections of the vertical fin, horizontal stab, rudder & elevator are not only readily identifiable but almost jump out of the box & into proper alignment. There is certainly no mistaking what we’ve got going on in this phase of the construction. And this is largely due to the fact that Bruce doesn’t employ the same build methodology for the V60 as he used with his Sig Four Star 40 or 120. Instead of creating a stick framework to be covered to produce a slab like empennage, he provides sections of solid balsa that are joined together to form these components of the tail.

Starting with the horizontal stab, it comes in 3 main pieces to be laid out over the plans: first is a 24” wide 5/16” piece of balsa that is most of the perfectly shaped rear part of the stab; next is a 1/8” X 5/16” spruce spar that runs the width of the main rear stab section (24”); & finally another 5/16” balsa piece that is the formed front section of the stab. These are glued together with Titebond & then there are 2 stab tips that are glued in place, which gives you the entire construction of the stab. Only thing left to do at this point is to sand the top & bottom to make it covering smooth.

With the elevator, which is provided in 2 separate halves, you start by sanding to bring the trailing edge down on each piece to about 1/16”. Then you take an 1/8” elevator joiner wire, & using the plans as a guide, mark where on the leading edge of the elevator section a hole will need to be drilled in order to join them (the photos below make this clearer). Next step is to drill & groove these pieces & then epoxy the wire in place. The location of the holes is also strengthened by covering them over with fiberglass tape that is impregnated with thin CA. Besides strengthening these areas of the elevator, this FG provides a hard point upon which to locate the control horn. This horn location is then predrilled for later installation after covering. Temporarily taping the elevator to the stab, & then sanding to round off the edges finishes the work here (the elevator is taped so the pieces are sanded as one piece so they will “flow” together at the tips according to the plans).

The vertical fin uses the same 3 pieces of balsa concept of construction, but here instead of employing a hardened spruce center spar, the individual pieces of wood (not dissimilarly sized) are all cut & joined together with their grains running in different directions. This is done presumably to achieve the same strengthening effect as is created by the spar in the stab. Very clever Mr. Tharpe!! The fin is then placed in its’ location in the fuse & the one-piece rudder is then taped on the back of the fin so that it is evenly lined up at the bottom. Finally it is given the same sanding in order to smooth it for covering & to round off all the edges except for the base of the fin that will be glued into the fuse.

At this point the plans call for taking a wire tail-wheel bracket that has been somewhat pre-bent, & then preparing it for installation between the fuse, fin & rudder. However, I elected to use a Sullivan tail-wheel bracket here which I hoped would allow for a somewhat simpler attachment method. Also due to its spring action mechanism, it will also work to absorb some of the taxiing, take off & landing shocks, & insulate the servos & rest of the airframe from them. Not very artfully put, but I hope you understand what I mean. So I needed to fit this bracket to the bottom end location of the fuse & also insert a thin strengthening plate of hardwood into the inside of the fuse bottom. I then predrilled this thickened area & installed blind nuts that will be used to attach the Sullivan bracket after covering. Included in the photos below is an image of this Sullivan bracket taken off their website.

As already noted above, here then are the photos that depict this work on the tail-feathers, or as Bruce more accurately characterizes it in the manual, “Tail Assembly”. Now I really am out of things to do & photos to take to keep the build log moving until I have two wing panels built & joined together to the stage of being ready for mating with the fuse. Since I am literally getting pretty close to being at that point, hopefully I can work fast enough to avoid any real gap in posting these next steps in this V60 build thread. I will do my best & be back online when there is something more to share.
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Old Mar 03, 2013, 03:56 PM
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Wish I'd made my K-E-os tailfeathers from sheet instead of my usual 'why use one piece of balsa when six will do' methodology.

Good tailwheel rig - that sprung connector arm will save your rudder servo from much Grief while taxying around etc.

D
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Old Mar 03, 2013, 04:35 PM
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Dereck - funny, I was looking earlier at your posting of the work your doing on your Keos tail-feathers, & kind of wishing that Bruce had done something more like that for the V60. I don't really know what if any difference there would be in weight, as I haven't bothered to test weigh any of the plane so far. I will weigh it when all completed, both to see how close it comes to the design spec of 7 to 7 1/2 pounds, & to know what the ratio of watts to pounds ends up being.

In his manual Bruce also cautions against using too little glue, so I am probably using too much, which will add more weight as well. And I've used the exact adhesives he calls for (I bought his optional glue kit) which means a fair amount of CA's. In the past I've used yellow wood glue primarily & kind of like the fact that when it dries, the water comes out of it to lighten things up a bit.

Thanks also for the support of the Sullivan tail wheel. I'm installing Hitec digital standard size servos, which I also haven't done before. So I'm trying to protect them as much as I can. And a much easier install than the plans. Cheers,

Jed
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Old Mar 09, 2013, 01:05 AM
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Venture 60 Build Thread Continued

Sorry for the recent lack of real progress in this V60 build. Not at all because I'm not totally interested in & committed to getting it done & in the air. Sometimes life just really does get in the way of this hobby, but I am committed to getting back to work on it.

Almost have the left wing panel finished & ready to be mated with its companion right side. Then I can start making some progress worth reporting & providing photos of it as well. Really, the left wing panel so far doesn't look any different than the right one that I already showed in my photos - well it is a mirror image, which had me thinking & looking at it every now & then - this goes here or where? Wingtip on which end? So please stay tuned & I will have some new stuff to share.

Jed
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Old Mar 11, 2013, 01:36 AM
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Venture 60 Build Thread Continued

Something that occurs to me that relates to both of the wing builds! When I removed the first panel from the build board, which had the plans covered with wax paper, I had quite a bit of glue (mostly the yellow kind) still adhering to the wood, & separation was possible but not without some challenges. I mentioned this in an email to Bruce & he opined that it must be due to wax paper changes in their chemistry.

So when I laid the next panel down I bought a roll of the Great Planes clear plan protector (basically the same thing you peel off of the back of their covering) which had good reviews, & was reported to be better than wax paper. Well, my result was that the yellow glue didn't create any problem, but the thin CA got in between the plan covering & mostly the main spar & trailing edge. When I lifted the panel off, it separated just fine but left a thin residue of glue that kind of rippled in places. I spent much of today carefully sanding this veneer of glue off.

At this point I'm not really sure which is worse. Maybe I created the problem by applying too much thin CA so that the excess got in between the panel & the plan protector. But that didn't happen with the wax paper. So next time I'm not certain I would use the new stuff. But I've got almost a whole roll of it left! But then nothing is too good for use or trial on this V60, so what the heck.

Jed
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Old Mar 11, 2013, 01:40 PM
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I am following your build closely because I just found a Venture 60 kit at my local hobby shop that was traded in for an ARF. It's from 2001 and according to Bruce, nothing has changed on it. For $89, I couldnt pass it up. It will be my first kit. Keep the pics and info coming! Great build you got going.
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Old Mar 12, 2013, 01:35 AM
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Warbird40 - first welcome aboard & really congrats on finding such a great deal on this wonderful kit. That wood in yours I'm sure has aged beautifully & I can attest to the fact that nothing in my plans is any different than yours. I don't know where Moreno is but suspect it may be fairly close to where I am in the CA desert - boy, I would have driven over there in a nanosecond to buy that same kit for that price.

But what amazes me is that Bruce is still only charging about $10 more since he last made these kits, which is only about a 7 or 8 percent total increase since his 2001 kits. With 3% inflation per year, that is very fair.

My apologies also for a slowdown in my activity due to some spousal health issues, but now I hope to get back on track again & up to speed. And I can almost guarantee that this will be one of the best build experiences you will ever have in this hobby. Not to mention ending up with a marvelous airplane! So please add your experiences, inputs & ideas to this thread - no pride of authorship here, only humble & appreciative interactions. Cheers,

Jed
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Old Mar 14, 2013, 09:57 PM
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look what made the cover of the IMAA Magazine!

Sorry for the crappy picture.Flash from the camera reflecting on cover.
sP
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Old Mar 15, 2013, 12:16 AM
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Komet44 - thanks for providing this info about this Flying King by BTE. Bruce has more pictures of it & a write up of how it won "Best of Film Finish" - Weak Signals R/C Show - Toledo 2012 on his website. Is there any additional coverage of it in the magazine or just a cover photo with credits inside? This kit is also one that you can still get from Bruce - it hasn't gone out of production like the V60 did for a while.

If I hadn't already electrified a Sig Kadet Senior, I have to admit I would be very tempted to tackle this build next. Particularly after finding out what a difference there is between Bruce's kits & I suspect almost all other kits, including the Sig. So maybe it will be next!

Jed
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