Building a fixed head tip drive

[rjet]

Hey guys,
I was in Toys R'Us yesterday (yes, I shop for big boy toys there) and saw a neat "hover copter" R/C toy that has a tip driven rotor and though I don't know how well it flies I would like to build a giant model of similar design to maybe attach a control line to like a blimp or modify to something like an autogyro. Here is one for sale on ebay http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5956585483
What is the best way to construct and testfly such a gadget? Or are there any custom builders who could help me build such an unconventional craft?

[David A Ramsey]

If you build a giant version of this thing, it won't be a gadget any longer. From the link photo, it looks like it's carrying an 8 cell AAA Nimi. Like to see how they wire through to the two tip motors.

Did ya get one? How big did ya wana build it?

[rjet]

I haven't bought one, but I'm tempted just to see how well it flies. It looks like the whole thing rotates with the battery directly connected to the rotor. I want to build one about 5 feet in diameter, but probably using only two blades to simplify construction. I need an aerial platform like a blimp for a project, but I don't like the complications of transporting large amounts of gas so I am looking at an alternative craft.

[David A Ramsey]

I'm also curious what kind of control it uses as I see it comes with a TX.

would make an interesting project.

[Stef]

The toy in question only has up down control with throttle. It's quite fragile the blade mounts break on landing easily. There are plans available on ebay for a tip driven copter from the 1960's it's a free flight but you could adapt. Maybe add directional control.

[rjet]

Stef, Thanks for the flight info. Are you sure you saw a tip driven helicopter plan on ebay? I only see an autogyro plan http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5957358501 Though the design may be simple, tip drives are almost unheard of and the only one I know to have flown is Cal Poly's human powered heli http://www.calpoly.edu/~wpatters/helo1.html

Another neat side effect is that you do not need a tail rotor as a pivoting carriage can stabilize with a fixed tail.

[Stef]

Rjet,
I have seen the plans from 2 different sellers. One is plans-plus they have a store.
The other is sbpress a seller. They rotate different plans and you need to check back.
If you can't find them let me know and I'll try to dig out my set. There packed away somewhere!

[mnowell129]

While the thing you are building is quite cool and I look forward to seeing it fly, it isn't a gyrocopter but a helicopter. Perhaps someone in the helicopter forum may have some ideas?
There are some plans out there for a jetex powered kinda tip driven copter.....
http://jetex.org/models/plans/plans-misc/article-plan-jh_3-man-5508.html

[mnowell129]

[QUOTE=rjet]Stef, Thanks for the flight info. Are you sure you saw a tip driven helicopter plan on ebay? I only see an autogyro plan http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5957358501 QUOTE]
You can download this plan at :
http://www.kaicurryservices.com/tapintothenet/vintagefarmplans/models/AutoGiroModel.pdf