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Old Oct 05, 2008, 05:58 AM
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Grow old disgracefully!
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Quote:
Originally Posted by jjmouris
Me fly something slow, a foam model, join a club?! You must be kidding right?!.......
Joe
I fly RC combat for relaxation after F5B - 6 up together all trying to cut each others streamers. Not so fast but just as much fun. And the cheaper the model the better .

Why not persuade 'others' in your area to have a go - you can even do it with a Twinstar

Dick
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Old Oct 05, 2008, 03:12 PM
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Dick
combat with everyone useing FPV would keep anyone occupied

that would be cool

Joe thanks for all you help, I re read your posts and you are a big help
thanks again

too bad there is not a contest in Seatle washington
I would be there lol
Old Oct 05, 2008, 04:16 PM
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FPV ?

Think i'll rather do something not RC related...... like rowing!

By the way, i would suggest everyone refrains from using any RFM prop below 30 seconds of motor, just a little warning.

Joe
Old Oct 05, 2008, 07:06 PM
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Originally Posted by jjmouris
By the way, i would suggest everyone refrains from using any RFM prop below 30 seconds of motor, just a little warning.

Joe
The reason being...? (You know that you can get reinforced versions, right?)
Old Oct 06, 2008, 05:37 AM
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The reason beying that i have just sent 10 pairs back to Rudy. Even the reinforced ones crack at that sort of power. The don't crack at the LE and TE at the root but they go along the carbon tows. You think this is okey but the crack keeps growing and i imagine at some point there will be no more stucture holding the LE to the TE and the whole thing will collapse. A bit like a spar with no shearweb.

The simple fact is that his wide prop design is not suited to the high power we are using now. There is to much mass to excellerate and brake at switch on and off. No matter how much carbon you put in there.

However, i know Rudy is working on something!

At the worlds he was flying a reinforced RFM 18x19 with 1/3 of the blade cord removed by hand from the TE side. What does that tell you?!

Below 4,5KW the reinforced wide props (not the 16x16) are fine.

Joe
Old Oct 07, 2008, 02:02 AM
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Hmm, and I was looking forward to abusing my 220/37 P4 on 5S with a 17x18 RFM... Maybe not such a good idea after all
Old Oct 07, 2008, 04:21 AM
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That Plettenberg motor (P4) will also not survive 5S. To much RPM for it's design / construction.

Joe
Old Oct 07, 2008, 04:32 AM
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Rudi does it successfully on a 16x17, and on a 17x18 the rpm is even lower, so I don't expect that to be the biggest problem...
Old Oct 07, 2008, 04:51 AM
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Are you sure Rudy said it was a normal 220/37/A1/P4 ?!

What i heard was that this was tried but not succesfull by a few, including the German team members.
Old Oct 07, 2008, 05:52 AM
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Quote:
Rudi does it successfully on a 16x17, and on a 17x18 the rpm is even lower, so I don't expect that to be the biggest problem...
Jeppe, maybe you should discuss it once more with Rudi, or accept that your motor will not last for long.

Rudi was not using the 16 x 17 wide in Kiev, but a modified 17 x 18, if I remember it correct.

Maybe better to use the 220/42/A1/P4 6.7:1 on 5S, if you want/need to power up

Tommy
Old Oct 07, 2008, 06:39 AM
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I have considered to go for a 42 long, but as I understand it is not available yet...

Rudi has used a 16x17 at all the Eurotour competitions I have attended...

My philosophy was that since Rudi gets about 33-35 sec motor on his 16x17, and this is what i have on 4S with the 18x19, then i could get more power by trying a 17x18 on 5S, and prevent the motor from overrev.
Well, I'll just have to try it out, only problem is to get the approval from the financial boss at home...
Last edited by JeppeA; Oct 07, 2008 at 07:18 AM.
Old Oct 07, 2008, 07:38 AM
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Quote:
Originally Posted by jjmouris
That Plettenberg motor (P4) will also not survive 5S. To much RPM for it's design / construction.

Joe
Ive run the 220/37 on 5S with a 16x16 and it is OK, but the motor run time is very short. This motor seems better suited to 18x19 on 4S

Mark.
Old Oct 07, 2008, 07:39 AM
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I think you might be wiser to change gearbox to 5.2:1 if you want a smaller higher RPM prop and shorter motor run times.

It certainly has worked for me with the Neu motors.

220/37/A1 P4 with 5.2:1 on 4S and RFM 16x17 should prove a very interresting and safe setup!

Joe
Old Oct 07, 2008, 07:41 AM
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Mark, 16x16 slim that is?

The 16x16 wide certainly will NOT handle that much abuse, reinforced or not!

Still, it seems there is a big chance it might throw a magnet.

Joe
Old Oct 07, 2008, 07:53 AM
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I don't want a smaller prop (at least not too much), I just want to try more power in less time, and see if it works for me or not...
After all, it depends if I can keep my climbs short enough!


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