Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

sundowner 50 with OS 1.20

Reply

Old 03-15-2012, 03:17 AM
  #1  
orthobird
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 734
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default sundowner 50 with OS 1.20

does anyone think it would be inappropriate to build a sundowner 50 with an OS 1.20 CI. they recommend a .40 to .52

if i did this, i would double up the thicknes of firewall and strengthen it with screws/plates.
and thicken the side panels.

[img]webkit-fake-url://9F35BC85-81E8-42C4-8F09-AE8591EB5F28/HAN4725-2.jpg[/img]

Attached Thumbnails Click image for larger version

Name:	Rp44990.jpg
Views:	26
Size:	15.9 KB
ID:	1738924   Click image for larger version

Name:	Hc92216.jpg
Views:	28
Size:	22.7 KB
ID:	1738925  
orthobird is offline  
Reply With Quote
Old 03-15-2012, 07:17 AM
  #2  
Bflighter
Junior Member
 
Join Date: Mar 2012
Location: , SD
Posts: 13
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

Ground clearance would be an issue, the prop would be too big.  That would be a huge powerplant for that model.  Weight maybe an issue also, a fellow flyer at our field has one with an OS 46ax with the battery up front and it seems to be a little nose heavy.  All that being said....I'd love to see it!!! Make sure you post a video!
Bflighter is offline  
Reply With Quote
Old 03-15-2012, 02:44 PM
  #3  
smoknrv4
My Feedback: (11)
 
smoknrv4's Avatar
 
Join Date: Dec 2003
Location: RR#7 Aylmer, ON, CANADA
Posts: 1,285
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

Too much beefing up mods to make it work, which means more weight not to mention the heavier engine on top of that and the little extra gain in horsepower is not worth it because its not going to be faster than just keeping it light with a 50 sized engine. Just my opinion.
smoknrv4 is offline  
Reply With Quote
Old 03-15-2012, 03:27 PM
  #4  
orthobird
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 734
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

i may do it, if i get enough encouragement.
what i would do is use a 4 blade prop, that would decrease the overall prop size down by 2 inches. 2 blade would be 15 x 10, a 4 blade prop would be a 13 by 8 or so. a os .60 can use a 13 x 6 prop, so a 4 blade prop on the 1.20 should work with the clearance.
the OS 1.20 weighs 11 ounces more than the OS .60 engine, with muffler.
the OS .60 puts out 1.7 hp at 16,000 rpm, if you can ever get it to that RPM
the OS 1.20 puts out 3.1 hp at 9000 rpm
that is almost double the amount of HP with 1.20 and weight difference would be 11 ounces on the motor
i would reinforce firewall and fuselage side aft to wing
that should not add more than 2 pounds with engine increase and plywood
instead of 7 pounds
it will be 9 pounds

does it still sound unreasonable?
orthobird is offline  
Reply With Quote
Old 03-15-2012, 03:45 PM
  #5  
orthobird
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 734
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

one problem
the os 1.20 distance from crankcase back plate to front end of crankshaft is 140 mm
and from firewall to prop hub (114 mm) , with consideration of the cowl, the engine would protrude by 22 mm
thay may not look good

Hmm

i will reconsider
if anyone encourages me,
i may still do it
orthobird is offline  
Reply With Quote
Old 03-15-2012, 03:46 PM
  #6  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,797
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20


ORIGINAL: cshahrdar

i may do it, if i get enough encouragement.
what i would do is use a 4 blade prop, that would decrease the overall prop size down by 2 inches. 2 blade would be 15 x 10, a 4 blade prop would be a 13 by 8 or so. a os .60 can use a 13 x 6 prop, so a 4 blade prop on the 1.20 should work with the clearance.
the OS 1.20 weighs 11 ounces more than the OS .60 engine, with muffler.
the OS .60 puts out 1.7 hp at 16,000 rpm, if you can ever get it to that RPM
the OS 1.20 puts out 3.1 hp at 9000 rpm
that is almost double the amount of HP with 1.20 and weight difference would be 11 ounces on the motor
i would reinforce firewall and fuselage side aft to wing
that should not add more than 2 pounds with engine increase and plywood
instead of 7 pounds
it will be 9 pounds

does it still sound unreasonable?
This is a recipe for a slow heavy airplane. First off HPfigures really mean nothing. The OS 60-120 engines are fairly low output engines. There really is not much out there that would get that airplane past 130-140 MPH. The best option would be one of the Jett 56 engines along with their muffler. That setup at best will do 130-135.

speedracerntrixie is offline  
Reply With Quote
Old 03-15-2012, 07:51 PM
  #7  
orthobird
Thread Starter
My Feedback: (1)
 
Join Date: Dec 2011
Location: shreveport, LA
Posts: 734
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

i wont do it, but it sure sounded like it could be very fast

any suggestion on a combo i could use to get a very very fast plane using glow?

what do you think can be the fastest:
2 cycle glow engine
4 cycle glow
4 cycle gas
2 cycle gas?

i have a zenoah G38 on a giant red stick, and it is a beauty
i have a evolution 50 cc on an extra 26%, it is solid
and an FG 36 saito gas 4 cycle on a super decathlon

but by far, the fastest i have is the sundowner 36 with the evolution .40 nx nitro engine
orthobird is offline  
Reply With Quote
Old 03-15-2012, 09:09 PM
  #8  
combatpigg
Senior Member
My Feedback: (3)
 
combatpigg's Avatar
 
Join Date: Nov 2003
Location: arlington, WA
Posts: 19,891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

If the 1.20 fits the confines of the cowl, that is the first consideration.

Beyond that, you would need the skills, knowledge and machine equipment to lighten that engine and set it up for higher rpm operation.
Otherwise, all you'll have with the stock engine is a plane that is good at vertical drag racing.

I'd ditch the carb and muffler. Run it with a venturi and crankcase pressure tap. That ought to save quite a bit of weight right there.
Open up the crankshaft as far as you dare and do the usual high rpm timing / porting mods.
Pay attention to lightening the piston as much as possible.

I'm just "thinking out loud" with these comments, none of them are "The Gospel" based on actual experience with this combo. I'm speaking from the perspective if I found this plane and engine under the Xmas tree and how I would approach the project.
combatpigg is offline  
Reply With Quote
Old 03-22-2012, 12:12 PM
  #9  
qd25
Member
 
Join Date: Oct 2007
Location: Auckland, NEW ZEALAND
Posts: 57
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: sundowner 50 with OS 1.20

I have been flying a 4000watts electric version of this plane for a few years the firewall flew out of mine on the first amp draw i did on it all that was holding it was a few drops of CA i did fix it and put many flights on that airframe, till the day the wing ripped out in mid air in mid air,I must say it is a fantastic flyer I have another one now a little faster

here is the vid of the last flight R.I.P. My old friend

http://www.youtube.com/watch?v=TwKz53OtODU
qd25 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