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#1 b5ff Dec 15, 2011 01:43 AM

Valenta Volcano
 
The thread Fantastic Valenta Volcano over on the sloping forum, has been closed (I'm not clear as to why, maybe because I mentioned FPV?) so I'm starting a new thread here about the Volcano. As I plan to electrify it, I'm opening the thread here on the Electric Sailplanes forum. I'll post photos here of my progress.

For those not familiar with the Valenta Volcano, here are some details on it:

http://www.valentamodel.cz/volcano.htm

It's available from Soaring USA. Bob says he has them with red or blue wingtips.

I'm planning to power it with a Scorpion S4025-16 on 8S spinning an RF 15x15 prop for about 1500W and a pitch speed of about 47m/s.

My next question to those who have built and flown the volcano is: what servos? I'm partial to Hitec so am planning to use HS-5125MG for the ailerons, HS-5085MG for the flaps, elevator and rudder and HS-5065MG for the spoilers. Are these going to suffice? In particular, are the HS-5085 beefy enough for these big flaps? I suspect they are as the flaps don't deflect so much. How about the placement of the elevator servo? Do I need a thin-wing servo in there or can I fit a HS-5085?

The alternate servo option is to use MKS DS-6125 Minis, which reportedly have a super-narrow dead band and with chrome-plated gears, don't develop as much gear lash as the brass gears of the Hitec servos. They don't cost much more, so not a bad idea. I could use them for the ailerons, flaps, elevator and rudder, but use HS-5065MG for the spoilers (as I already have a pair waiting for use).

#2 Neil Walker Dec 15, 2011 09:02 AM

5085 are what I have in the flaps, and the elevator/rudder. No problems. The elevator ends up being a tight fit and needs some judicious grinding of the control horn and clevis. I think I have 85's for the spoilers, but pretty much anything would do there. I wouldn't bother spending the $$ on digis just for spoilers.

I did quite a bit of surgery to the flaps and the trailing edge of the wing surface to get more deflection so I could have a proper crow setup for landing. Basically cut off the wipers and trimmed a few mm from the trailing edge wing skin so I could get about 60 degrees deflection, and added a home-made wiper to cover the gap made by trimming the wing skin.

#3 b5ff Dec 15, 2011 04:07 PM

Quote:

Originally Posted by Neil Walker (Post 20145021)
5085 are what I have in the flaps, and the elevator/rudder. No problems. The elevator ends up being a tight fit and needs some judicious grinding of the control horn and clevis. I think I have 85's for the spoilers, but pretty much anything would do there. I wouldn't bother spending the $$ on digis just for spoilers.

I noticed from cvanscho's photos on the previous thread that the elevator servo is a tight fit. I see a thin wing servo (HS-5125 or similar) in there to provide more enough room for the horn. I'm also thinking that servo opening could be moved to the side a few mm.

Quote:

Originally Posted by Neil Walker (Post 20145021)
I did quite a bit of surgery to the flaps and the trailing edge of the wing surface to get more deflection so I could have a proper crow setup for landing. Basically cut off the wipers and trimmed a few mm from the trailing edge wing skin so I could get about 60 degrees deflection, and added a home-made wiper to cover the gap made by trimming the wing skin.

If you have photos of this process or end result I'd like to see them. I, too, would like to get more deflection from my flaps as I'm usually landing in tight spots. No lush alpine meadows or fresh-mowed farmers' fields where I live.

On the topic of spoilers, are they included/installed or do I have to source out a pair? If I need to provide, what size would be required? I could even go with TopModel electrical spoilers, which have the servos built-in.

#4 Neil Walker Dec 15, 2011 09:15 PM

Mine is in a storage locker at the moment while I move, but I'll snap some pics when I get a chance. Spoilers are included, but you have to fashion your own linkage for them.

#5 b5ff Feb 03, 2012 09:28 PM

My Volcano finally arrived! I ordered it from G. Staufenbiel (http://www.modellhobby.de/) in Hamburg as they had the best price online of all the dealers that responded to my email. I had to wait a month for them to get them in stock, and it showed up at my door about 2 weeks later.

The model arrived undamaged and looking really neat. I can't even find the slightest flaw in the gelcoat. The canopy is already mounted and the model is painted in-mold. I chose the stock white with blue/yellow wingtips.

I can't start putting it together straight away. Rather, I won't allow myself to as I've got a few other models in the queue. I hope to get to it in about a month.

#6 BladeRunn Apr 03, 2012 04:01 PM

Quote:

Originally Posted by b5ff (Post 20633997)
My Volcano finally arrived! I ordered it from G. Staufenbiel (http://www.modellhobby.de/) in Hamburg as they had the best price online of all the dealers that responded to my email. I had to wait a month for them to get them in stock, and it showed up at my door about 2 weeks later.

The model arrived undamaged and looking really neat. I can't even find the slightest flaw in the gelcoat. The canopy is already mounted and the model is painted in-mold. I chose the stock white with blue/yellow wingtips.

I can't start putting it together straight away. Rather, I won't allow myself to as I've got a few other models in the queue. I hope to get to it in about a month.

B5FF, where is your operations base? Are you located in the US? If so, would be nice to hear how much that shipping set you back.. planning to get a Volcano to make company to my Alpina 4001 (same plane, just molded wings on the Volcano)...
Did you maiden it already?? Pictures or, in the lack of them, comments at least??

#7 b5ff May 16, 2012 10:38 PM

Hi BladeRunn. I'm in Canada, so YMMV, but their shipping was decent, 50Euro. The problem was that customs somehow thought I was importing auto parts and tacked on a hefty tariff.

I've not even started building it yet. You know how it goes; life gets in the way. I hope to have it flying within a month, however.

Quote:

Originally Posted by BladeRunn (Post 21227034)
B5FF, where is your operations base? Are you located in the US? If so, would be nice to hear how much that shipping set you back.. planning to get a Volcano to make company to my Alpina 4001 (same plane, just molded wings on the Volcano)...
Did you maiden it already?? Pictures or, in the lack of them, comments at least??


#8 Slopeangel Jul 06, 2012 08:55 AM

Late to the party, but I've put together a brief tour of mine. Hope this is useful to anyone considering the Volcano...

Valenta Volcano - a brief tour (3 min 6 sec)

#9 Woodstock 1 Jul 06, 2012 09:41 AM

Hey Paul, good one! Didn't know you had a Volcano, I'm sure you'll enjoy it!

Chris

#10 Slopeangel Jul 06, 2012 01:55 PM

Quote:

Originally Posted by Woodstock 1 (Post 22089580)
Hey Paul, good one! Didn't know you had a Volcano, I'm sure you'll enjoy it!
Chris

Yes I'm a bit slow on the uptake as I know that you've always liked and promoted yours. It certainly looks the part and I'm looking forward to the maiden. If only it would stop raining........

#11 Woodstock 1 Jul 06, 2012 01:58 PM

Don't mention the "r" word :mad:...

By going 5 or 6 cell you seem to be aiming at pretty hotlinerish performance, is that right?

#12 Slopeangel Jul 06, 2012 04:58 PM

Quote:

Originally Posted by Woodstock 1 (Post 22091590)
Don't mention the "r" word :mad:...

By going 5 or 6 cell you seem to be aiming at pretty hotlinerish performance, is that right?

The power system in the video is giving around 1400 Watts on 5s and I plan to up that in stages with different props (or more cells), to around 2000 Watts.

Some of the great and good of our hobby have described this as "barely lukewarm" :popcorn:

#13 Slopeangel Jul 13, 2012 02:25 PM

8 Attachment(s)
Some pictures of the first flight

#14 Woodstock 1 Jul 13, 2012 02:32 PM

Quote:

Originally Posted by Slopeangel (Post 22092989)
The power system in the video is giving around 1400 Watts on 5s and I plan to up that in stages with different props (or more cells), to around 2000 Watts.

Some of the great and good of our hobby have described this as "barely lukewarm" :popcorn:

Wow - I'm running under 1Kw on a tiny 4s. It does what I need, which is to rescue me at the slope if I run out of lift.

Photos look great! Flight report :popcorn: ?

#15 Slopeangel Jul 13, 2012 03:25 PM

Quote:

Originally Posted by Woodstock 1 (Post 22154950)
Photos look great! Flight report :popcorn: ?

Maiden flights were all for a photoshoot, so my musings won't be particularly insightful. But first impressions were very positive.

It's not a floater and is not going to be a model that will turn on a sixpence, but it is very rewarding on big aerobatics. The inertia can be used to move around the sky looking for lift which meant that I could stretch out the "power off" phases at the slope in very light lift. But "coring" a thermal was a challenge. Things might get a bit more responsive when I move the cg back. The canopy came off during the second flight (stupid pilot didn't fasten it properly) and the handling hardly seemed to be affected, although I didn't hang around getting the model back on the ground. That suggests to me that the cg can go back a long way from Valenta's recommendedation ( 83 mm from leading edge). It would be interesting to hear where others have got their cg.

The power set up is a little intoxicating and its a lot of fun burning the amps to get some energy into the model for slope aerobatics. I love the way it can be steered around some of the vertical stuff on its rudder.

Which makes me wonder if I've gone the right route with my Volcano. I'm aiming to use mine on very light lift days and it's going to be great for that. I can see that a heavily loaded pure glider Volcano would be very well suited to the slope and might get a lot more use.


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