help with motor

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pvbachan
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help with motor

Post by pvbachan »

Hi everybody !

Will try to build a couple of e-fighters this fall to fly with my son, maybe other folks here in Minneapolis.

Do you have any recommendations for me at this point in time ?
It seems that for the price the BP 12 combo is hard to beat ?
What has your experience with reliability of BP motors been ?
They have a new motor for $40 - anyone tried that one ?

I hope to promote some more combat in these areas.

Thank you
thojo
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Post by thojo »

They have been working out great for me, especially at prices you can get them at. Only weak link is the long shaft, which bends easily. My fix has been to cut the shaft at the threads and bring it down to about a 1/2 inch, then use a prop collet. The shorter shafts are less likely to bend in a crash...
RH
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Post by RH »

Between my brother and me, we have one BP12 and two BP21 combos. We just love em, great set-up for the $. I did smoke one ESC when I put on a 10x4.7 and didn't check the load but that was my fault. I like Joe's short shaft idea.

rh
thojo
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Post by thojo »

Here is a link to the fix thread...

http://www.rccombat.com/forum/topic.asp?TOPIC_ID=11461
pvbachan
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Post by pvbachan »

thanks for your replies,
sorry that motor for $40 is the new custom CDR- any opinions on that motor ?
From your experience , what are the weights of:
1.motor + esc+ 2 cell 1300 battery+ 3 servos
what should the target fuse ? and target wing ? weight be ?

Petr
thojo
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Post by thojo »

I don't have specific weights Petr, but I can tell you definately the CustomCDR motor will weigh less than the BP motors, which are quite heavy compared to some...

12oz or less is optimum, but some of mine are flying at 13 and 14oz very well...
rdc767
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Post by rdc767 »

Petr I have flown up to a 18oz model with the bp 21 and 12. Run a 8x6 apc slo flight prop. I just flew my gws corsair at 16oz. I ran a 3 cell 1800mah battery. It is fast and agile!!!.

I bought this set up for a friend it is similiar to the bp 12.
The prop saver is a must.
http://www.balsapr.com/common/keywordSi ... Id=V190506

http://cgi.ebay.com/Outrunner-Brushless ... dZViewItem

Good luck
Ron
Eric M
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Post by Eric M »

Hi,
Some building stages weights
fuze, wing and tail (2 mil coro) with water based paint: 5.25 oz
with the tape applied: 6.125 oz
ready to fly: 13 oz with BP 21 and 1500mah 2 cell lipo

Radio battery and motor depending upon componts types weigh between 5 and 7 oz.

Hope this helps

Eric
pvbachan
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Post by pvbachan »

thanks, guys, I found a nice deal on ESSKAY 400XT motor on hobby-lobby site - one for 29.99 -- they have pretty good reviews on ezone.

thinking about getting the BPbrushless controller 10AMP for them.
drewjet
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Post by drewjet »

The BP motor is hard to beat on price. I have on and it makes plenty of power. However it is heavy and the shaft is way too soft fot the rigors of combat. I have been building my own CD-ROM motors. But you can buy one from Customcdr.com http://www.customcdr.com/thestorezone/p ... 79a762efor $35 and is a much better way to go. My planes are ending up in the 9 to 11 oz range.

Drew
thojo
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Post by thojo »

Petr,

Esskay's run better on 3 cell, bearly run on 2 cell li-pos! If you get the Esskay, make sure the 2 cell li-po is high output, or you'll be disappointed.

I have 2 I'm not using....
rdc767
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Location: USA

Post by rdc767 »

get the bp18 amp controller for the same price its worth having a bit of extra amp protection.
Bender
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Post by Bender »

Strange behavior: each engine itself work perfectly, but do not working together one of them stop working. Became very hot. And has tendency rotate in opposite direction.
Image
Any ideas for solving the problem?

Great Planes Rimfire 22M-1000 Brushless Motor 2
Great Planes Silver Series 35A Brushless ESC 5V/2A BEC 1
drewjet
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Post by drewjet »

Most brushless motors will not be happy running 2 motors from one speed controller. Part of it is the long wires, also a big no no on brushless. Just remember when building a twin, it like one airplane for the price of two!

Drew
rdc767
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Post by rdc767 »

I would think those ssc props on an electric would be very in efficient. They turn 8600 rpm as oppose to 17500. In addition, the electric props are much lighter. Props are everything in electrics.
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