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Electric Stunt => Gettin all AMP'ed up! => Topic started by: Wynn Robins on December 04, 2011, 03:10:06 PM

Title: Retracts
Post by: Wynn Robins on December 04, 2011, 03:10:06 PM
now we have all the gear to do retracts - how many have actually done them?

I am retrofitting some into a brodak Spitfire I have framed up and would like to see what others have done.


I think planning on using the before you build a wing is a good idea - just going on the issues I had installing them into the Spit wing - they look cool working tho!!!!!
Title: Re: Retracts
Post by: Robertc on December 04, 2011, 03:46:25 PM
I've done three planes with retracts, but was before I went electric.  Maybe late next year I'll do
another retract plane, possibly a twin.

Robert Compton
Title: Re: Retracts
Post by: Avaiojet on December 21, 2011, 10:28:19 AM
now we have all the gear to do retracts - how many have actually done them? I am retrofitting some into a brodak Spitfire I have framed up and would like to see what others have done.
I think planning on using the before you build a wing is a good idea - just going on the issues I had installing them into the Spit wing - they look cool working tho!!!!!

Wynn,

Quote
how many have actually done them?

I've installed at least a dozen sets of retracts in pattern ships, starting back in the 80's. Sure, R/C, but the model doesn't know.

I've installed retracts in Warbirds also and I have designed gear for 30's Racers that were fixed.

I design and built a set out of wood, as a markup for the retract gear, I will build for a scale Grumman F3F I started to build for R/C, but will now be CL.

I designed scale gear for an 80" Bamboo Bomber, but I expect to scale this model down for CL.

I did an unusual application for a scratch built scale BEA Hawk. I have photos of that gear because I sent them to another modeler. Here's fixed gear I built for a 30% Gee Bee Z. Yes, too large for CL.

CB

Title: Re: Retracts
Post by: Dean Pappas on December 21, 2011, 11:32:32 AM
Hi Wynn,
I do think that Wil Hubin has made a special version timer with an electrical retract channel output.
You will need a high current BEC (battery eliminator circuit) to run electrical retracts like the Eflite units.
That's what Bob H. plans on using for the retract equipped twin.

Regards and good luck,
                            Dean
P.S. many many moons back, Werwage and I spent 32 sleepless hours cutting a set of servo-driven retracts into one of his old I-beamers!
Now that was not the preferred method, for sure!
Title: Re: Retracts
Post by: Wynn Robins on December 21, 2011, 12:10:44 PM
Hi Wynn,
I do think that Wil Hubin has made a special version timer with an electrical retract channel output.
You will need a high current BEC (battery eliminator circuit) to run electrical retracts like the Eflite units.
That's what Bob H. plans on using for the retract equipped twin.

Regards and good luck,
                            Dean
P.S. many many moons back, Werwage and I spent 32 sleepless hours cutting a set of servo-driven retracts into one of his old I-beamers!
Now that was not the preferred method, for sure!

thanks Dean,  I have the Hubin retract timer and Eflite electric retracts - they work extremely well - they are in  the Spitfire wing at the moment - hope to get it covered and ready to fly early next year .
Title: Re: Retracts
Post by: WhittleN on December 21, 2011, 02:06:57 PM
Wynn
Paul Walker has done some stuff with the combination you have. You may need to PM him.
As I recall he had to go to a BEC 10A to bring them up during flight.
Not quite the same as pattern, I know you are concerned about every gram.
Norm Whittle
Title: Re: Retracts
Post by: Wynn Robins on December 21, 2011, 02:12:05 PM
Wynn
Paul Walker has done some stuff with the combination you have. You may need to PM him.
As I recall he had to go to a BEC 10A to bring them up during flight.
Not quite the same as pattern, I know you are concerned about every gram.
Norm Whittle

thanks Norm - I might do that.  I have done a lot of testing on the bench - motor loaded to full RPM with prop etc and the retracts work fine ...... I am only using an ICE Lite 50 -with built in BEC (5A).  seems to work......or am I missing something?   
Title: Re: Retracts
Post by: Mark Scarborough on December 21, 2011, 02:51:39 PM
Wynn,
some ESC can carry the load on the battery eliminator circuit some cant. I seem to recall that the Castle Phoenix series is ok with any three cell application but at least in RC they cannot be trusted with a 4 cell or 5 cell system. I am not really clear on how that would impact the retracts. Just more information for you.
Each ESC is specifically different in this regard, perhaps communication with Castle, ( or the manufacture of your choice) would be very enlightening. Please share if you find any more  out from them. I believe last I heard Paul was using a Shulzie (?) ESC which as I understand is rather different than Castles. Then again, the Castle ICE series I think is rated for a higher "servo" load so may work fine as opposed to the Phoenix series.
Title: Re: Retracts
Post by: Wynn Robins on December 21, 2011, 04:38:17 PM
that might explain a few things.....

I am running a 4s system  and it seems fine - I am thinking of going to 5s but will see how it affects the retract side of things.

I will be the first in NZ to run retracts on a stunt plane - so that will be a second first for me...... #^
Title: Re: Retracts
Post by: WhittleN on December 21, 2011, 04:59:33 PM
Wynn

Paul uses 5 cell.  Suggest you contact him, he is a very helpful guy not to mention a fastidious engineer.

Norm
Title: Re: Retracts
Post by: Will Hubin on December 22, 2011, 12:59:49 PM
Paul did the retracts with the Plettenberg motor and the Schulze ESC (no BEC). Initially he tried the E-flite retracts with the BEC provided by the 7805 linear regulator that is a part of the FM-9R timer. He found that, on the bench, it would retract and extend one gear leg fine but didn't have enough current capability for both. He then went to the Castle Creations external BEC, the Rx Battery Eliminator (0.4 oz), which utilizes a switching regulator that is much more efficient with the high voltages of 4S and 5S batteries; it promises a continuous 5A at 5.0 volts. The ICE also uses a switching power supply for its BEC and promises up to 5A also, so I suspect it will work for both 4S and 5S batteries. (Paul mentioned to me at the Nats that he had made more than 50 flights with the retracts, with no problems with them, even on hard corners.)
Title: Re: Retracts
Post by: Wynn Robins on December 22, 2011, 01:19:06 PM
thanks Will - thats what I wanted to hear!!!!  should be fine from what you say here - I'll let you all know how they go!!!