RE: BVM EDF
 

well....it would probably not get as much attention if he left it open ;)

all a part of marketing....

RE: BVM EDF
 

High power EDF are about the same price as a single Wren 44 turbine engine. These two EDF's would be just about the same price as a Jet Joe turbine but they are 90mm diameter fan units. Around $1600-$1800 ready to fly. Cost is similar to glow ducted fans without all of the frustration. Chris would know what the all up ready to fly Viper would cost with a 120mm diameter fan. Performance increases every year with advances in battery, motor and fan technology.

[link=http://www.crosswindcomposites.com/videos/F22F16.wmv]Video 1[/link]

If I want to go fly my EDF all I need to take to the field is the plane, my TX, a couple flight packs and a hand pump for the retracts/gear doors.
I dont need a turbine waiver.
I can fly at almost any field. No restictions.
Just plug it in and go fly.

RE: BVM EDF
 

It is probably due to two reasons. Covering the intakes increases the hype and speculation. If it is just a proof of concept build then he would not want people to see another manufacturers fan installed if he plans on marketing his own fan unit. Other than that there is no point.

RE: BVM EDF
 

I'll give you the power system cost break down on two different sized jets I converted last year.

Savex turbine ready L-39:
[link=http://www.rcgroups.com/forums/showthread.php?t=382085]http://www.rcgroups.com/forums/showthread.php?t=382085[/link]

[link=http://www.rcgroups.com/gallery/showphoto.php?photo=23262&sort=1&cat=500&page=1]Video of 2nd flight[/link] performed mostly at half throttle.

[ul][*] Fan -- Schubler 90mm (all carbon composite) -- $290[*] Motor -- Lehner 1940/12 -- $300[*] ESC -- Hacker 77A -- $220[*] LiPo Batteries -- 8S4P -- $520[*] Total -- $1330
[/ul]
The numbers for this setup are 46A and 1400 watts.

Yellow Aircraft A-4 (the below listed components would work on converting a plane the size of the BVM Viper).
[link=http://www.rcgroups.com/forums/showthread.php?t=349026]http://www.rcgroups.com/forums/showthread.php?t=349026[/link]
[ul][*] Fan -- WeMoTec 124mm (all carbon composite) -- $200[*] Motor -- Lehner 2250/13 -- $400[*] ESC -- Castle Creation HV110 -- $275[*] LiPo Batteries -- 8S4P -- $520[*] Total -- $1395
[/ul]
The numbers for this setup are 88A and 2600 watts.

Not cheap, but still about half the cost of a turbine for similar performance levels. I must add that the components used to put together the above power systems are all top of the line. Cheaper setups can be had but performance may go down.

Kirk

RE: BVM EDF
 

Safety violation

Aren't you supposed to charge LiPos out of the aircraft in a fire proof box???




Maybe they are using NiCds instead, or Kryptonite......

RE: BVM EDF
 

http://www.rcgroups.com/forums/showthread.php?t=433586

RE: BVM EDF
 

No danger, it's a equipped with the prototype VioHalon fire supression system ;)

RE: BVM EDF
 

Nah, that's not necessary. As long as you are following proper procedures, it's fine to keep the batts in the plane for charging.

RE: BVM EDF
 

Its my guess, whatever power system BV pics... it will cost a lot more than that...!!
I bet some beers, it will be ~$2000.... This is just my guess.. I have no real info..

Eddie Weeks

RE: BVM EDF
 

[sm=idea.gif] Whet everyone should consider is this. If you recall the Savex L-39 was designed for electric and many are flying it using an 8 lb. Turbine like Wren 44.
BVM is thinking ahead. These jets that he is introducing to be used for electric can easily use the WREN 44. Very smart thinking.

RE: BVM EDF
 

Absolutely. A LOT more. Good for him, I say. Stick to the top end of the market, he built a name, might as well use it.

RE: BVM EDF
 

Besides planes, I'm also into railroading, old cars and woodworking.
As you know our small (as in number of participates) hobbies advance due to technology developed by other large corporations.
Our hobby manufacturers use this technology and apply it to our hobbies, ie, motors, electronics, etc.
Batteries are the same way: Just last fall, a mfr came out with a new cordless drill using lipos.
The lipo drills aren't cheap but as more tool mfr's come over, more will be made and this drives down the price.
This will carry over to our hobby.
Price is a very big factor in our hobby: if a pilot can outfit his plane for about the same price as an engine, he'll jump in.
In addition, I think a lot of fields may be getting 'closed in' by development.
It they fly electrics, no one will be *****ing at 'em and forcing them to close.
I haven't done electrics yet but if prices come down enough, I'll probably jump in.

RE: BVM EDF
 

This is what I am working on now. Outside Dia. Still 4” but I reduced the center section to fit around the motor I chose, which is an Astro 40 brushless. I’m using 5 full size Viojett rotor blades (center re-cut, see photo) and 4 stators , why re-invent the wheel, the center of the motor tube gets drilled out later. Power is 20 cell GP3300’s (24 volts), Astro 40 brushless, and PHX. 80 controller. Weight of the complete power system is 4lbs. The motor is rated at 60A continuous but I draw 80A with the batteries right off the charger! I limit the amps to 65A at full throttle by programming the throttle channel end points. So, 24v x 65A = 1560W (2.09 H.P.) But then there is the real world with the 24V pack, 18V x 65A = 1170W (1.6 HP). I get around 4 1/2 +/- lbs. of thrust at around 27,000 rpm at full throttle and 65A, on good days, with no intake lip or reduced tail pipe. The PHX seems to change power outputs on me, anyway, all this for under $350.00 (used parts). Some day I will spring for 6s2p 6400 lipos. I’m just waiting for the price to come down, but the cans (3300’s) are working well for me now. The balsa Mig-15 airframe finished weighs 1lb. 5 oz., good 45 sized fun. I can’t wait to see what BVM is doing! I know Astro Bob is working on a brushless 60 for the Byron impeller also! That will be fun.


Also, I have received some pm’s on how the 4” Viojett rotor is attached to the FAI 640 6 turn brushed motor. I have enclosed a photo of the custom machined prop adapter. You just remove the center aluminum piece in the Viojett, put the screws and spinner back on and bolt this on.

RE: BVM EDF
 

Oops typo, I get 4 1/2 lbs @ 22,000 rpm. I can't read my own notes.;) This is a conservative figure, my controller and rpm sensor are goofy. Installed in my old Mig with a rounded lip I would pull close to 5 3/4 lbs. on a fish scale.

RE: BVM EDF
 

I think it likely Bob is working on his own design EDF fan unit to get the max performance out of today's technology. Bob is an engineer at heart and always tries to push the envelope with top end, original product. If it is his own design, and it is still under development, it stands to reason he wouldn't want to expose it yet.

As to the choice of planes, it is likely he wanted to get this ready for Florida Jets and the viper presented the least amount of work to adapt to target weight, performance and size.

He and I chatted a bit about it after the Thursday demo, and while I am not quoting him by any stretch, these are the opinions I formed.

I think it is pretty exciting that BV would put his development efforts into the EDF marketplace as I think he could move this segment of the hobby forward significantly in the next several years in ways other manufacturers wouldn't or couldn't.

RE: BVM EDF
 

Agree with Keith 100%

RE: BVM EDF
 

http://www.rcgroups.com/forums/showt...2&page=8&pp=15

RE: BVM EDF
 

Hey Vargas, you need to share how you built your center hub/adaptor, I have a Viofan at home and would like to try your approach.

RE: BVM EDF
 

I agree with Kieths statement wholeheartedly. So much so that I got on the list for a few power packages and a Lightweight Viper. There were people in front of me and behind me doing the same.

Regards, Bill

RE: BVM EDF
 

Pretty simple really. Balsa rocket parts, glassed, sanded. Make a cross on the end , then trace & dig out with a dremel channels for the stators (BVM part). Glue them on, fair in the base and drill out the center for the motor. I will add holes right behind the stators to help cool it. It does get hot at 65A. The 4" 7 blade Viojett is not my approach all credit goes to Dave Ribbie.

RE: BVM EDF
 

Yeh, I'm going to be on that list too!

RE: BVM EDF
 

Your probably right but BV would be shooting himself in the foot if he did charge that amount for a power system. The motor he is using is a Nue Motors ORK (Out Runner Killer). Steve Nue admitted so much on RCGroups. That is a $200 motor and it needs a 9S or 10S LiPo pack. The abosulte best 120mm fan that is just starting to hit the market is the Schubler DS-94 all carbon fiber fan with factory balanced rotor. It cost about $350, depending on the Euro exchange rate. It has hit 80N (18 pounds of thrust) during testing using a Lehner 2280 High Amp motor. The cost of that motor is $525. The controller used was a Schulze 40-160. It can handle 40 cells and 160A continous. Cost is between $622 and $675, depending on where you buy it. This setup also used a 14S LiPo pack which cost about $960. Currently, this is the ultimate EDF setup and cost about $2500. IMHO BV is not using anything close to this setup, yet.

Kirk

RE: BVM EDF
 

Stop giving everything away! Plug your intakes! After all, it's all TOP SECRET.

I think there are pretty standard components under the hood. And once a purple sticker goes on them, the price will double. There are still people who beleive that Bob somehow makes aeropoxy different when he puts his sticker over the Locktite one.
If he really had anything new, he would show it, no?

He's no dummy, though, you have to hand it to him, and he's going to sell a ton of these!

RE: BVM EDF
 

Ooops. Posting at the same time!

Just as I figured. Off the shelf components. Hence the secrecy.
He should do it right, the BVM way, and have all new stuff designed from the ground up.

RE: BVM EDF
 

Also make the shroud on 4" drain pipe. Make the prop adapter (or have Eddie Weeks do it), Cut the rotor on a lathe to 4", bolt it together and go have fun. I have cad drawings for the rotor/prop adapter.