Zinger and Master Airscrew?

I have a MA 5.4x4 cut down to a 4.75x4 and it works great on Reed or a Tee Dee.

Jim

My favorite prop for all 1/2A engines is the Master Airscrew GF series 6x3, cut down to 5.5, 5.25, and 5" with rounded tips. The main time I vary from that is if I am flying a really fast plane like the Norvel powered Baby Flite Streak  or Tee Dee powered Li'l Satan on 35' lines, in which case I use an APC 6x2. That one lets the engine spin up to full power without flying too fast for comfort. I use the old style spring starters on most of them. The snap starter will work just as well with all of them too.
Just $1.69
http://masterairscrew.com/6x3gfseriespropeller.aspx
Rusty

I've never like the Zinger ones, the blades are too thick...

MAS are fine, and as said before, as easy to cut down in size too.

Can one of you who has expertise in cutting down props, go thru your routine to explain to the rest of us how it's done.

I mean I get the reduction in diameter, but then how do you finish it by rounding the ends, finishing and polishing the new surfaces, etc.?

Inquiring minds want to know!

TIA

There is not a whole lot to it, take note of the tip shape, cut equal amounts off of each blade then sand the tip shape back in.

Rebalance and then go fly!

Depending on your flying discipline you can get deep into it or not. For sport flying the method I described gets the job done!

Ron

I agree with Kris, the wood Zingers are pretty blunt but the leading and trailing edges can be sanded down into a pretty nice prop.

There's a lot of different methods to shorten props, do what works best for you. Here's a couple things:

-Get a prop balancer, it a must.
-Fingernail/toenail works great on a small nylon prop, balance out with emery board....or sanding block.
- When you shorting a prop the pitch increases, so a 6x3 cut down 1" is going to be like a 5x3.5 or 5x4, not sure what the formula is, but since the angle is a average it could be figured out.
-Use a wood screw the same diameter as the crank to mount on a piece of wood, measure prop from center, mark wood where you want to cut prop, use an X-acto knife to make a small mark on prop, rotate 180 and mark prop at same spot.

Mark Boesen wrote:...-Use a wood screw the same diameter as the crank to mount on a piece of wood, measure prop from center, mark wood were you want to cut prop, use an Exacto knife to make a small mark on prop, rotate 180 and mark prop at same spot.

Yep, nail clippers or scissors work for cutting most brands. I use a sharp pointed caliper and a ruler with grooved markings to set the width.

Then do what Mark said with the wood screw and knife to score it, only set one leg of the caliper in the prop center, scribe it with the sharp tip on the other legs. Then I shape with sandpaper to round the edges. And balance by sanding carefully on the back side of the heavy blade.
Rusty

I like to think of props like wings beyond the dia. / pitch I consider their cord and airfoil shape attributes. Most small wood props typically produce good lift at lower rpm do to their inherent thicker airfoils thus translating to thrust. I think they can be a good choice dependent of aircraft type. Sometimes wood props fit perfect with scale vintage crafts draggy by nature slower by size and design make perfect photogenic subjects as they drift past the camera. The one thing that I like to do to improve the prop is a little refinement around the hub to increase the useful available thrust. See the posted pic of a  6x 4 Zinger by removal of some additional wood increases performance extending the airfoil closer to the hub. Of course another solution rather than a spinner nut is to cover the blunt area with a larger dia. full shape spinner the 6 x 4 prop only has 4in of exposed functional blade, cleaning up the blunt area you can obtain a useful 5 x 4 prop. Zinger cut their props this way the 7 x 3.5 can be reworked to expose a 6 x 3.5 with an over all dia of 7" If you embark in taking the time to fine tune this brand of props they are worth trying. If you ever get your hands on a Tornado wood prop you will have an example of perfection in wood.






Tornado 7 x 4 (3.8g) / Zinger 7 x 3.5 (7.1g)