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General control line discussion => Open Forum => Topic started by: Dick Pacini on June 04, 2012, 03:18:04 PM

Title: Prop Question
Post by: Dick Pacini on June 04, 2012, 03:18:04 PM
What is the opinion of Zinger props vs Brodak BY&O props?  The Brodak prop resembles the old Top Flite paddle blade and the Zinger looks more like the old Top Flite Power Prop (which I never cared for).

These props will be used on a Brodak B40 pulling a Brodak P40 ARF.  Which prop would do a better job?
Title: Re: Prop Question
Post by: Wynn Robins on June 04, 2012, 03:33:27 PM
are they your only choices?  I would use neither.....  the BY&O props are average to say the least - the Zingers area slightly better as a prop kit - eg- somewhere to start shaping a prop from....
Title: Re: Prop Question
Post by: Brian Massey on June 04, 2012, 03:42:36 PM
The best, and "only" answer is to try them both; I'm not trying to be funny. I've tried props and recommended them to my brother who did not have good results. I currenly have a Zinger 11/4 pulling an LA 46 powered 53 ounce Trophy Trainer. I launce at 9850 RPM and get 5.25 laps with good power over the top. The Zinger replaced an APC 11.5/4 that gave me the same lap times but NO tension on overhead manuvers. I've also had very good luck with a Zoar 11/5, but lap times were a tad faster, closer to 5 flat. I've also tried the much hearlded APC 12.24/3.75. It pulled the plane nicely, but I lost all tension on outside corners. Very Scary.

I used to fly a 52 ounce chipmonk with a B40. I don't remember the launch RPM  but I used a Beechwood Master Airscrew 10/6 and was very happy with that combo.

I don't believe there is a magic formula that will tell you which prop is best; just gotta try them.

This probably wasn't much help. Oh well.

Brian
Title: Re: Prop Question
Post by: dennis lipsett on June 04, 2012, 04:08:50 PM
Iam currently using an Xoar 10/5 prop on my Brodak 40 and I'm impressed with it. Beautifully made and the balance was good. Prop works in the overheads too.

Dennis
Title: Re: Prop Question
Post by: Tim Wescott on June 04, 2012, 04:12:06 PM
Try a couple of different APC props, too.  The more I use them, the more I like them.  Any time I backslide and use a wood prop, I like the APC's even better!
Title: Re: Prop Question
Post by: peabody on June 04, 2012, 04:30:26 PM
Randy sells a nice Thunder Tiger prop for that engine, and a lot are using APC 11 X 4's or a "magic" 10.5X4.5 APC.
Have fun!
Title: Re: Prop Question
Post by: kenneth cook on June 04, 2012, 05:08:25 PM
         Hello Dick, I'm not sure if you've flown the plane, but the majority of P-40's I've seen flown including mine all have been quite tail heavy. This was using a heavier APC and spinner combo. This was also using a LA.40 which is almost 2 3/4 oz's heavier than your B-40. My LA.40 is using the Thunder Tigre 11x4.5 as Peabody mentioned and this prop is quite heavy.  All of our club members aside from one, are all flying LA46's on that particular plane. I'm not suggesting your engine isn't powerful enough, I'm just saying it's much lighter.  That being said, the .46 so I'm told is lighter than the .40. I know the instructions don't give you a CG at least mine didn't. I'm just saying that using a woodie up front is certainly lighter than the composites. Just something to keep in mind. Ken
Title: Re: Prop Question
Post by: Dick Pacini on June 04, 2012, 06:41:14 PM
Ken I got part of one flight in last summer.  The hinges were too stiff because I got CA in them.  I ended up doing an inverted belly flop coming out of an outside maneuver.  I was running a Zinger prop.  The plane had good line tension.  I ended up with a broken fuselage.  I repaired that and replaced the tail feathers with new parts and hinges.  All is good now.  Waiting for a break in the weather.

The CG spec is on page 17 of the instructions under Finishing.  It calls for 2 3/8" back from the leading edge at the fuselage.  I didn't have to add any weight other than the prescribed tip weight.
Title: Re: Prop Question
Post by: Phil Coopy on June 04, 2012, 06:57:07 PM
With different aircraft designs, engines, fuel mix, flying conditions, and flying styles, it's pretty hard to predict a prop that will make you feel good without a lot of experimentaton. fex. I have two identical Vector 40's....one with an LA46 and one with a Stalker 46, they fly very differently with the same props, but I have them flying close to the same with unlike prop selections.

Phil
Title: Re: Prop Question
Post by: Steve Helmick on June 08, 2012, 11:41:42 PM
If you have a later generation B.40 with the big muffler outlet and .305" venturi, 10% nitro, the TT 11 x 4.5 will be excellent (Tower Hobby, $12 for 6 count bagfull). Some guys like the 10.5 x 4.5 APC, and 11-4 Xoar and RSM 10-6 would might be worth a try, but the TT is a real good bet. FWIW, I tried clipping one down to 10.75" and couldn't get it to rev as high as a full 11". I think the thin, sharp tips are important.  H^^ Steve   
Title: Re: Prop Question
Post by: Dick Pacini on June 09, 2012, 12:31:18 AM
If you have a later generation B.40 with the big muffler outlet and .305" venturi, 10% nitro, the TT 11 x 4.5 will be excellent (Tower Hobby, $12 for 6 count bagfull). Some guys like the 10.5 x 4.5 APC, and 11-4 Xoar and RSM 10-6 would might be worth a try, but the TT is a real good bet. FWIW, I tried clipping one down to 10.75" and couldn't get it to rev as high as a full 11". I think the thin, sharp tips are important.  H^^ Steve   

Is that a Thunder Tiger nylon prop?
Title: Re: Prop Question
Post by: Jim Thomerson on June 09, 2012, 08:38:06 AM
Fly and try is the ticket.  I worked one of the Zinger 11 x 5 prop kits into a beautiful prop.  I flew it and it was very good.  Unfortunately, I then put on a same size  unworked Zinger prop kit, and could not tell a difference in performance. HB~>
Title: Re: Prop Question
Post by: Garf on June 09, 2012, 03:45:58 PM
Is that a Thunder Tiger nylon prop?
TT=Thunder Tiger. I tried a TT 11-4.5 on my NoblARF/Brodak 40. It made a difference. The Zinger 11-5 is good, the XOAR 11-4 is excellent. I even tried the XOAR 11-5E prop. The jury is still out on that one.