[sorkai]

Just acquired a semi scale 4M Ventus for small money,and starting to check it out ,it soon became obvious that you only get what you pay for-on the surface it looks pretty good but going under the skin you soon find some pretty sloppy and weak construction- I believe it was original sold by Raidentech in the US but of Chineese origen- Just wondering if any one out there has any experience with this Model? so we could exchange some ideas- the plane is set up for aerotowing but i'm going to convert it to electric and beef it up, as it is now needs a couple of pounds up front to balance so there should be lots of room for electric gear- Will keep you posted with my big winter project!

[FD av8r]

If you google the glider, there used to be some very lengthy threads covering lots of folks doing e-conversions etc on this plane. For sure many had good/bad and ugly experiences with them. I felt that it looks awesome, but was worried that what was hidden underneath might not stand up to frequent use.

I hope you can make a go of it, and please post as you do

Daryll

[sorkai]

First step done-After looking inside at the wing tube area I did not like what I saw , a thin frayed .fibreglass tube where the wingrod constantly got stuck in- the wingrod is a 1/4 inch carbon rod filled with a hardwood dowel, after looking for some other material for the tube I found thick wall aluminum tubing with the exact inside diameter at Cdn. Tire--- The holes in ribs now had to be enlarged and i did that with taking a piece of the tubing ground some teeth in the end and attached it to my drill, that gave me a perfect fit- now the new tubing in with lots of WestSystem resin and 405 adhesive filler.

[Charlesd]

Hi Sorkai,

Where did you get the Ventus? I keep seeing this ebay auction but I doubt it's the same one. The one on ebay is manufactured by XY and sold by RCJetsWorld.




http://rcjetsworld.com/index.php/products/glider

[sorkai]

I got this from a club member- he had had it it for years without doing anything with it- but i'm pretty sure it came from Raidentech- Here is a link to RC Universe where i found a lot of info: http://www.rcuniverse.com/forum/rc-g...us-glider.html

[sorkai]

Making progress!

Looked at the hinge for the flying stab and found a lot of play, was unable to remove the hinge so I added some shims that fixed it- Inside of the cockpit had to be ground out to make make room for Batteries etc. next came the dreaded job of cutting of the nose, made up a jig with a hole same size as the spinner, i have always fought that job with other projects, this way i could get the right alignment and with the backplate for the Hyperion 3025 motor i'm using it was easy to align the motor with a bit of down trust. Then I reinforced the inside of the fuse with more layers of fiberglas and West System resin all the time keeping an eye on the weight- I then painted the inside of the canopy and added some glass because it was kind of flimsy and i could use more weight-The plane would have needed at least two pounds up front the way it came- and I'm still short and will have to buy some heavier batteries, after done I figure total flying weight to be at little over 10 pounds, with the motor i'm using and a 10x8 prop and 3cell batt. i should get around 1200 Watts witch is more than i need. Now just some clean up and making some decals- i can't wait for S P R I N G

[kcaldwel]

Which Hyperion 3025 motor are you using? Only the -04, 1545kV, comes close to 1200W number on 3S with a 10x8" prop.

That motor and prop combo won't be very efficient at glider speeds (pitch speed is 171kph!). A lot of the power (240W) would go to heat and prop losses. The climb won't be very good. And the rpm (13,900) will be far past safe limits for a folding prop.

eCalc only shows a few hundred watts on the 3025-08 (867kV) with a 10x8", so I guess that isn't the motor you are using? It would be a better choice, with maybe a 14x9" prop. More thrust at a more reasonable speed for a glider, and lower rpm.

Kevin

[sorkai]

Originally Posted by kcaldwel

Which Hyperion 3025 motor are you using? Only the -04, 1545kV, comes close to 1200W number on 3S with a 10x8" prop.

That motor and prop combo won't be very efficient at glider speeds (pitch speed is 171kph!). A lot of the power (240W) would go to heat and prop losses. The climb won't be very good. And the rpm (13,900) will be far past safe limits for a folding prop.

eCalc only shows a few hundred watts on the 3025-08 (867kV) with a 10x8", so I guess that isn't the motor you are using? It would be a better choice, with maybe a 14x9" prop. More thrust at a more reasonable speed for a glider, and lower rpm.

Kevin

Hi Kevin- Thanks for your input- Yes I am using the -04 ( P.S. they don't make that model anymore)- have used it in another 3meter model with good success- but i do agree that a 14x9 would be a better choice, however according to Hyperions prop chart it would mean going to a 2 cell battery and 850 watts and I might take that route, only problem to get the weight I want, I will have to get a 10000mah and they do get pricy.

[kcaldwel]

Yeah, 2S would be a lot of amps!

I think Hyperion is getting out of motors entirely. If you like the 3025-04, they have some incredible prices on the remaining stock:

$21.48US

http://www.allerc.com/brushless-moto...-7_76_165.html

$48.20, cheaper shipping:

http://aircraft-world.com/shopdispla...que+outrunners

Aircraft World also has the 3032-08, 699kV, for $62US, or AlleRC has the 3032-04, 1252kV, for $17.87 (!) if you need nose weight anyway.

Kevin

[michaely]

Originally Posted by sorkai

Hi Kevin- Thanks for your input- Yes I am using the -04 ( P.S. they don't make that model anymore)- have used it in another 3meter model with good success- but i do agree that a 14x9 would be a better choice, however according to Hyperions prop chart it would mean going to a 2 cell battery and 850 watts and I might take that route, only problem to get the weight I want, I will have to get a 10000mah and they do get pricy.

Subscribed..... there's always been a big scale glider in my dreams.

10,000 mah lipos are pretty exotic; why not serial connect a couple of 5000 mah 2s lipos, of which there seems to be a fair amount of choice.
..... for example, the Hobbyking Turnighy hardcase 2s/6000mah/25C/371gram lipo is $25.75 (their 'one time offer' price that pops up after a minute of being on the item)....

good luck,