Go Back  RCU Forums > Glow Engines, Gas Engines, Fuel & Mfg Support Forums > Gas Engines
Reload this Page >

Final setup details on my new gas plane!

Notices
Gas Engines Questions or comments about gas engines can be posted here

Final setup details on my new gas plane!

Old 01-21-2012, 05:05 AM
  #26  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,821
Received 18 Likes on 16 Posts
Default RE: Final setup details on my new gas plane!


ORIGINAL: kmeyers


ORIGINAL: gagallagher04401

20x8? alright I will get one. Is the plane flyable with the 18x8 that is on it though? What is going to be the difference?

Also is their a way to put a cone on this engine/plane? Would look a little nicer I think.

Thanks
George
The differance is RPM. The load of an 18 x 8 is less at a given RPM so the engine will try to spin faster. The heat and friction go up with RPM. The Main Crankshaft bearings are sealed, if they get hot they will outgas their grease and fail prematurely. The CRRC 40 is not a Zenoah.

The bigger prop (20 x 8) will put more power into moving air at a lower RPM then into making frictional heat at a higher RPM.

The spinner is the same as any plane: Spinner backlplate, prop, washer, prop nut, spinner nut adaptor, spinnner and last spinner bolt.
The 20" will act as an air brake as well. They don't "coast" like an 18". Seen most easily on speeds on short final and any kind of down line when flying.
Old 01-21-2012, 06:29 AM
  #27  
gagallagher04401
Senior Member
Thread Starter
My Feedback: (20)
 
Join Date: Dec 2007
Location: East Millinocket, ME
Posts: 260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!


ORIGINAL: ahicks
The 20'' will act as an air brake as well. They don't ''coast'' like an 18''. Seen most easily on speeds on short final and any kind of down line when flying.
Not sure if I understand this staement?

What size spinner typically for a plane of this size?

Thanks
George
Old 01-24-2012, 12:26 AM
  #28  
kmeyers
 
kmeyers's Avatar
 
Join Date: Jan 2004
Location: lake in the Hills, IL
Posts: 900
Likes: 0
Received 12 Likes on 12 Posts
Default RE: Final setup details on my new gas plane!


ORIGINAL: gagallagher04401


ORIGINAL: ahicks
The 20'' will act as an air brake as well. They don't ''coast'' like an 18''. Seen most easily on speeds on short final and any kind of down line when flying.
Not sure if I understand this staement?

What size spinner typically for a plane of this size?

Thanks
George
Well the pitch @ rpm = an air driven speed. If that speed is faster than the plane is currently traveling the plane accelerates. If slower it acts as a brake. When acting as a brake the effect is greater as the diameter increases.

What ever size spinner looks the best.
Old 01-24-2012, 04:00 AM
  #29  
gagallagher04401
Senior Member
Thread Starter
My Feedback: (20)
 
Join Date: Dec 2007
Location: East Millinocket, ME
Posts: 260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

Thanks!

Another question, I have been balancing the prop (Wooden Top flite 18x8) How "perfect" does it need to be? I would call mine "close" not perfect. When It had nothing added toit it, it was WAY off, now it is "close" Is that good enough? Just having trouble getting it "perfect" I would think perfect would not matter because as it gets chipped, dinged up etc... it will no longer be "perfect anyway.

Thanks
George
Old 01-24-2012, 08:12 AM
  #30  
ec121
My Feedback: (2)
 
Join Date: Jan 2003
Location: Billingsley, AL
Posts: 737
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

I h ad a Quadra 40 with an 18x6 on a 72in. Stik Biplane. It wasn't enough prop. It would fly the plane, but an 18x10 worked better. I had ground clearance problems with the tail dragger, so a larger prop wouldn't work. I ended up with a 3-bladed prop. Measure from the prop shaft to the ground with the fuse level then figure the prop diameter you can use with adequate ground clearance.
Old 01-24-2012, 09:00 AM
  #31  
ahicks
My Feedback: (2)
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,821
Received 18 Likes on 16 Posts
Default RE: Final setup details on my new gas plane!


ORIGINAL: kmeyers


ORIGINAL: gagallagher04401


ORIGINAL: ahicks
The 20'' will act as an air brake as well. They don't ''coast'' like an 18''. Seen most easily on speeds on short final and any kind of down line when flying.
Not sure if I understand this staement?

What size spinner typically for a plane of this size?

Thanks
George
Well the pitch @ rpm = an air driven speed. If that speed is faster than the plane is currently traveling the plane accelerates. If slower it acts as a brake. When acting as a brake the effect is greater as the diameter increases.

What ever size spinner looks the best.
You could look at it this way too. All else being equal, that 20" prop is punching a bigger hole in the air - creating way more drag at idle/reduced power. It's fair to think of it as a solid disc actually. Also, going from an 18" prop to a 20" prop will generally call for a reduction in pitch (to keep comparison fair). The flatter blade/reduction in pitch will also act as a brake. The only downside to the move would be a reduction in speed - and generally anyone flying a sport, 3D, or aerobatic plane generally doesn't care about top end too much. Guys with big control surfaces need to avoid it actually. 6" of pitch is generally plenty!
Old 01-24-2012, 09:14 AM
  #32  
gagallagher04401
Senior Member
Thread Starter
My Feedback: (20)
 
Join Date: Dec 2007
Location: East Millinocket, ME
Posts: 260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

Yeah people have mentioned giong with a bigger prop 20x6, 18x10. Plane has a 18x8 on it. I have no idea how to choose a prop for it. Engine is a CCRC 40cc engine.

IT will fly with my 18x8 right?

Thanks
George
Old 01-24-2012, 10:43 AM
  #33  
frieshoo
Senior Member
My Feedback: (20)
 
frieshoo's Avatar
 
Join Date: Jan 2002
Location: Fries, VA
Posts: 1,026
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

ORIGINAL: gagallagher04401

Yeah people have mentioned giong with a bigger prop 20x6, 18x10. Plane has a 18x8 on it. I have no idea how to choose a prop for it. Engine is a CCRC 40cc engine.

IT will fly with my 18x8 right?

Thanks
George
18x8 should be fine. My buddy has a ccrc 40 and he has a 20x8 PT carbon fiber prop turning about 7500rpms. Your 18x8 should turn about 7000rpm or so, new. It will get stronger as it gets more run time.
Old 01-24-2012, 11:34 AM
  #34  
gagallagher04401
Senior Member
Thread Starter
My Feedback: (20)
 
Join Date: Dec 2007
Location: East Millinocket, ME
Posts: 260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

Thanks!

Another question, I have been balancing the prop (Wooden Top flite 18x8) How "perfect" does it need to be? I would call mine "close" not perfect. When It had nothing added toit it, it was WAY off, now it is "close" Is that good enough? Just having trouble getting it "perfect" I would think perfect would not matter because as it gets chipped, dinged up etc... it will no longer be "perfect anyway.

Thanks
George
Old 01-24-2012, 01:17 PM
  #35  
frieshoo
Senior Member
My Feedback: (20)
 
frieshoo's Avatar
 
Join Date: Jan 2002
Location: Fries, VA
Posts: 1,026
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!


ORIGINAL: gagallagher04401

Thanks!

Another question, I have been balancing the prop (Wooden Top flite 18x8) How ''perfect'' does it need to be? I would call mine ''close'' not perfect. When It had nothing added toit it, it was WAY off, now it is ''close'' Is that good enough? Just having trouble getting it ''perfect'' I would think perfect would not matter because as it gets chipped, dinged up etc... it will no longer be ''perfect anyway.

Thanks
George
Get the 'tip' balance as close as possible. 'tip' balance has the the blade tips at the 3 o'clock and 9 o'clock position. If this is close, you will be fine.

Do you have a good balancer?
Old 01-24-2012, 05:16 PM
  #36  
gagallagher04401
Senior Member
Thread Starter
My Feedback: (20)
 
Join Date: Dec 2007
Location: East Millinocket, ME
Posts: 260
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Final setup details on my new gas plane!

Thanks alot, so I am good then, I was worried I had to get it dead perfect.

The balancer I have is not the best but it works, they call it a finger tip balancer, but I use two tall glasses to balance it on, works pretty good.

Thanks again!

George
Old 01-25-2012, 07:08 AM
  #37  
BarracudaHockey
My Feedback: (11)
 
BarracudaHockey's Avatar
 
Join Date: Jul 2003
Location: Jacksonville, FL
Posts: 26,205
Received 263 Likes on 209 Posts
Default RE: Final setup details on my new gas plane!

If you're that worried, get a Vess balance ring.

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 - Do Not Sell or Share My Personal Information -

Copyright © 2023 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.