41 replies to this topic

[Jairus]

Tower Hobbies delivered a new propeller today. Very aggressive pitch and looks powerful standing still for only 4" diameter. Not going to complicate this build by adding contra-rotating propellers just yet. Shooting for simple the first time out and work up from there.

Also decided to use an old Mura Gp 20 to power this one.

[gascarnut]

Has anyone thought of trying one of these:



2" diameter with a 3mm shaft hole, made for electric power ducted fan flying. I guess this might work a bit?

The nice part about them is they are designed to work at very high speeds, typically 30,000 rpm and upwards, bolted straight onto the shaft of a brushless motor, so a Gp 20 with 3:1 gearing or so would really wind them up.

And they sound so cool too.......

[Jairus]

Dennis, I wanted to do a Duct Fan originally. Seems more efficient than a two blade prop thrashing away in the wind. But I never found a good fan for sale on Tower Hobbies. Whole units yes, but not just a fan. Besides the clearances are tight and retro fitting might be harder than building a correct Retro Jail Door chassis...

So I decided to go the simplest route for the first time out.
However, could you please post a link to the one you found?
Thanks.

[Foamy]

Then again in the 80s. That's my experimental twin-motor UFO from Area 51, against Foamy's (Dennis Hill) champion RC motor "Bladerunner" rail car at Valley Raceway in Rosemead, CA. Maybe foamy remembers how fast we went. He did this a bunch, while I was the impostor from Las Vegas.

Hey, somebody got a picture of my heap! The drag strip at Valley was not very good. It had the wrong paint on it for traction, and it had no timing system. The local kooks started making air cars for giggles. The popular motor came from a Makita cordless drill. I saw this and thought to myself "this is going to be shooting fish in a barrel". Had that dragster sitting around, had a Big Jim modified R/C motor, added one cox prop on a Astro Flight adaptor, and had my way with them. The car had a roar that sounded like the Hounds Of Hell were chasing you. . .

. . . about a year later somebody (Guy?) came up with a real light machine that had 2 group 20 motors and small hand made props. Real low CG, the thing crushed me into the ground.

[gascarnut]

However, could you please post a link to the one you found?

Great Planes Hyperflow

[HarV Wallbanger III]

Well Jairus got it right... OSHA must have told him it had to have a prop shroud! Looks cool! DO IT!

[Cop Cake]

Dennis, I wanted to do a Duct Fan originally. Seems more efficient than a two blade prop thrashing away in the wind. But I never found a good fan for sale on Tower Hobbies. Whole units yes, but not just a fan. Besides the clearances are tight and retro fitting might be harder than building a correct Retro Jail Door chassis...

So I decided to go the simplest route for the first time out.
However, could you please post a link to the one you found?
Thanks.

I was thinking the design of the prop on an "Alligator Boat" would provide the right thrust. This one is obviously too tall, but........

Alligator Swamp Boat

[Guy Spaulding]

Hey, somebody got a picture of my heap! The drag strip at Valley was not very good. It had the wrong paint on it for traction, and it had no timing system. The local kooks started making air cars for giggles. The popular motor came from a Makita cordless drill. I saw this and thought to myself "this is going to be shooting fish in a barrel". Had that dragster sitting around, had a Big Jim modified R/C motor, added one cox prop on a Astro Flight adaptor, and had my way with them. The car had a roar that sounded like the Hounds Of Hell were chasing you. . .

. . . about a year later somebody (Guy?) came up with a real light machine that had 2 group 20 motors and small hand made props. Real low CG, the thing crushed me into the ground.

Same Guy!

Those motors were a mismatched pair of Trinity cobalt motors. An Infinity and a DBX, both running some worn out 27 arms. Running at different RPMS, the car made a blood-curdling shriek when it blew down the track. The propellers were from Cox .010 engines

I've been keeping a secret, all these years, until now, Foamy!

I was taking the hole-shot because you were running foam tires on the back that were just sticking to the glue, while my big "O" ring rear tires rolled through!

Here's the man, feverishly trying to adjust the timing to get a little more out of that RC motor


Those were the days, my friend
!

[HarV Wallbanger III]

Ok lets see... pic has Guy in it, Gerry Gustin, Frank Baldozer and myself at the counter.... I think the guy to the left is MR. Boolaman Gil Gunderson????? Yep those were the days of So Cal USRA when we had big entries!

[Guy Spaulding]

And everything was cool with Joe at the helm!

[macman]

Hey Barney... Did you have hair back then??? You were sure missing a bunch in '90 when I met you in Atlanta...

Nice to see you guys back then, but what became of the hot-pants babe behind the counter???

[Guy Spaulding]

That's Joe's wife in the foreground, his mother in the background. That may even be Tore way in the back. Barney should be able to shed more light on this one

[macman]

& I guess it was Joe's raceway...

[Guy Spaulding]

Yea, he owned Valley Raceway in Rosemead.

[Superbird]

Prop power sounds OK but Rockets are better, I can assure you! Back in the day on my basement strip we used Estes rockets to power slot cars. Strip power lit the igniters and away they went! The speed and sound were impressive although technically, probably not as fast as normal rail cars. The real excitement was provided by the eject charges going off after the car was buried in the stopping silk. Of course, we were prepared to put any flames out quickly. Between that and fire burnouts our strip was never dull.  

[don.siegel]

I don't know, kinda like the prop-powered cars. Here's one from back in the day - a short experiment in a production model, with maybe four made that we know of... And for the braking issue, it's got solenoid powered brakes! 

Don 

 

 

[Jairus]

Dang if you guys are not going to get me back on that project now!