Electric Training If you are new to electric learn more about them here or ask questions.

stopping prop?

Reply

Old 06-11-2011, 06:45 AM
  #1  
Mikel-t
Thread Starter
My Feedback: (12)
 
Join Date: Dec 2002
Location: Ellicott City, MD
Posts: 408
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default stopping prop?

I'm going to maiden a G.P. combat Corsairs {conversion} without LG. I need to know if I can make the prop stop Horizontal to the ground before I land it on grass... Thanks, Mikel-T
Mikel-t is offline  
Reply With Quote
Old 06-11-2011, 07:04 AM
  #2  
1320Fastback
Senior Member
 
1320Fastback's Avatar
 
Join Date: May 2008
Location: Northern Occupied Mexico, CA
Posts: 998
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

If your ESC has a "Brake" then yes you can.
You will have to blip the throttle a couple of times get it lined up before touch down.
1320Fastback is offline  
Reply With Quote
Old 06-11-2011, 07:53 AM
  #3  
Mikel-t
Thread Starter
My Feedback: (12)
 
Join Date: Dec 2002
Location: Ellicott City, MD
Posts: 408
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

Yes the ESC has programmable Brake...but you are saying Blip the throttle....so, its BY-CHANCE? no matter what?
Mikel-t is offline  
Reply With Quote
Old 06-11-2011, 11:57 AM
  #4  
1320Fastback
Senior Member
 
1320Fastback's Avatar
 
Join Date: May 2008
Location: Northern Occupied Mexico, CA
Posts: 998
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

Yes, I have a couple of foams that belly land and it usually only takes 3 or 4 blips until the prop stops horizontal.

On final approach there is plenty of time to get it just right.
1320Fastback is offline  
Reply With Quote
Old 06-12-2011, 01:01 AM
  #5  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

I agree, an ESC based brake will stop the prop but it will not align it with the ground.   I am not aware of any device that stops the prop in a specific spot.

Many people who belly land use "prop savers" which use rubber o-rings to mount the prop..  There are a variety of companies that make them.
aeajr is offline  
Reply With Quote
Old 06-12-2011, 06:22 AM
  #6  
1320Fastback
Senior Member
 
1320Fastback's Avatar
 
Join Date: May 2008
Location: Northern Occupied Mexico, CA
Posts: 998
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

I have seen a system in a sail plane with a retractable motor where the prop stops in the same orientation every time so it can be retracted.

Knowing the prices of these large sailplanes means it would be better to just buy a few hundred props and change them when needed.
1320Fastback is offline  
Reply With Quote
Old 06-12-2011, 07:04 AM
  #7  
aeajr
My Feedback: (2)
 
aeajr's Avatar
 
Join Date: Jan 2003
Location: Long Island, NY
Posts: 8,567
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

Or you can put a folding prop on the plane so it folds back when you land, depending on the shape of the nose.
aeajr is offline  
Reply With Quote
Old 06-12-2011, 10:55 AM
  #8  
Lnewqban
 
Lnewqban's Avatar
 
Join Date: Apr 2007
Location: South Florida
Posts: 4,056
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

http://www.wattflyer.com/forums/showthread.php?t=22069
Lnewqban is offline  
Reply With Quote
Old 06-12-2011, 06:24 PM
  #9  
Mikel-t
Thread Starter
My Feedback: (12)
 
Join Date: Dec 2002
Location: Ellicott City, MD
Posts: 408
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

Ok. I think I got it. So the 3-blade prop is definitely out!....Anyone recommend E-Retracts ? or should I start a new thread.?
Mikel-t is offline  
Reply With Quote
Old 08-09-2011, 06:40 PM
  #10  
ray foley
 
ray foley's Avatar
 
Join Date: Aug 2002
Location: toledo, OH
Posts: 150
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

hi there from Toledo

Back to the future

Okay, I have been flying epowered airplanes since before brushless motors, before lipos, and even before NIMH cells. So back in the prehistoric days to stop a prop was also a concern and since no ESC (and they were analog not digital!!) at the time had a brake function, you had to stop the prop mechanically.

How to stop a prop

What we did was to take a servo and a piece of nyrod and install the outer rod from the servo through the front firewall and past the motor stopping just behind the prop arc. The servo was connected to the retract channel and so was switchable. The inner nyrod was the attached to the servo arm in the usual manner and the length of the inner rod was adjusted so that the inner rod would extend just a little bit into the plane of the prop so that when extended the inner rod would interfere with the prop's rotation and buzz like a cicada if the power were on. If the motor was turned off and just freewheeling, this interference was enough to stop the prop and stop it in the same position every time. It saved props during landings without LG but you had to replace the inner nyrod every so often and it did scuff up the TE of the prop a little but so it goes.

This really worked quite well, give it a try.

ciao -rjf
ray foley is offline  
Reply With Quote
Old 08-10-2011, 08:29 AM
  #11  
Mikel-t
Thread Starter
My Feedback: (12)
 
Join Date: Dec 2002
Location: Ellicott City, MD
Posts: 408
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: stopping prop?

Well Done my prehistoric friend....I was sure there was a bigger brain than mine out there . Furthermore, I used to fly electrics before there were motors & batteries! they were called RUBBER BANDS! LOL THanks again for an ingeniuos solution!
Mikel-t is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service