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

DLE 20cc Gasser! (Data & Links 1st Post)

Old 05-19-2012, 05:37 AM
  #5476
chandley43231
 
chandley43231's Avatar
 
Join Date: Apr 2010
Location: columbus , OH
Posts: 292
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

ok guys heres maybe a question already adressed in the past     so if i put my DLE into my tp P-51d hurry honey it will of course have to be put in inverted  woops i jsut called a buddy an found   daaa you cant just rotate the carb 180 degrees  i put my ignition just behind the fire wall  with my lower open slot in front of the wing dows connection getting a rcexl opti kill swtich get pics  soon have the plane on u tube http://www.youtube.com/watch?v=icOo1...feature=relmfu
chandley43231 is offline  
Reply With Quote
Old 05-19-2012, 06:45 AM
  #5477
microdon2
 
Join Date: Apr 2009
Location: Whitestone, NY
Posts: 1,883
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

av8tor \ ahicks - on your posts about reading the plug electrodes, you say you need to run the engine at full throttle for at least a minute and then cut it cold, but can't do that on the ground, or it'll overheat. So we're talking about a planned deadstick?
microdon2 is offline  
Reply With Quote
Old 05-19-2012, 07:06 AM
  #5478
octanehuffer
 
octanehuffer's Avatar
 
Join Date: Jul 2006
Location: Lakeland, MN
Posts: 917
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Yes. That is the best way to check a tune. Kill it after WOT. Drag racing, I kill the car after my pass and coast to the return road and pull over to the side and check plugs. With a plane, you will need to deadstick
octanehuffer is offline  
Reply With Quote
Old 05-19-2012, 09:14 AM
  #5479
ahicks
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,457
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: microdon2

av8tor \ ahicks - on your posts about reading the plug electrodes, you say you need to run the engine at full throttle for at least a minute and then cut it cold, but can't do that on the ground, or it'll overheat. So we're talking about a planned deadstick?
No, actually the method I'm talking about is more about spotting a trend? You don't have to dead stick/land. Idling for a minute isn't going to change it enough to matter.

I think you need to fly it, and if everything seems right, you can verify that with a plug reading. Trying to adjust a carb on an engine that doesn't seem right in the air using plug readings doesn't usually work well, for me anyway.

I'm not sure I would ever run a setting that might overheat the engine on the ground? I've never had trouble that way?
ahicks is online now  
Reply With Quote
Old 05-19-2012, 01:29 PM
  #5480
mach2
 
mach2's Avatar
 
Join Date: Nov 2011
Location: bakersfield, CA
Posts: 1,107
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: chandley43231

ok guys heres maybe a question already adressed in the past so if i put my DLE into my tp P-51d hurry honey it will of course have to be put in inverted woops i jsut called a buddy an found daaa you cant just rotate the carb 180 degrees i put my ignition just behind the fire wall with my lower open slot in front of the wing dows connection getting a rcexl opti kill swtich get pics soon have the plane on u tubehttp://www.youtube.com/watch?v=icOo1...feature=relmfu
Not sure of your question. But if you are asking about rotating the carb upside down, or 180 degrees, then yes, i dont see any reason why you cant. I posted this to another person probably a few pages back. Page 215, post 5372

If you do it right, it should be fine. Pull the two screws out and flip it with the nylon intake. dont rotate the aluminum back plate though. (the aluminum plate on the back of the crankcase, that the nylon intake goes into).

however, running it inverted, this allows you to adjust your H and L needles from the top. I like this on my plane. Maybe you dont want to cut a hole in the top of your cowl.

Jeremy

mach2 is offline  
Reply With Quote
Old 05-19-2012, 01:37 PM
  #5481
av8tor1977
 
av8tor1977's Avatar
 
Join Date: May 2003
Location: Tucson, AZ
Posts: 6,938
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Cooling airflow isn't sufficient on the ground for most cowled airplanes for sustained full throttle runs. The aircraft really needs to be moving through the air to have sufficient cooling for sustained full throttle operation. I realize one would think the prop blast would be enough, but in many cases it's not....

AV8TOR
av8tor1977 is offline  
Reply With Quote
Old 05-21-2012, 11:49 AM
  #5482
DwightMann
 
Join Date: Sep 2004
Location: Mohave Valley, AZ
Posts: 168
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: av8tor1977

Cooling airflow isn't sufficient on the ground for most cowled airplanes for sustained full throttle runs. The aircraft really needs to be moving through the air to have sufficient cooling for sustained full throttle operation. I realize one would think the prop blast would be enough, but in many cases it's not....

AV8TOR
Equally important, the load on the engine will change.
DwightMann is offline  
Reply With Quote
Old 05-21-2012, 03:53 PM
  #5483
av8tor1977
 
av8tor1977's Avatar
 
Join Date: May 2003
Location: Tucson, AZ
Posts: 6,938
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Yes, that's quite true. A good portion of the prop blade is stalled when standing still, causing a higher load on the engine. That's why an engine turns much higher rpms in the air. How much higher depends on the prop pitch and the drag of the airplane.

AV8TOR
av8tor1977 is offline  
Reply With Quote
Old 05-22-2012, 04:15 AM
  #5484
ahicks
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,457
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: av8tor1977

Yes, that's quite true. A good portion of the prop blade is stalled when standing still, causing a higher load on the engine. That's why an engine turns much higher rpms in the air. How much higher depends on the prop pitch and the drag of the airplane.

AV8TOR
Some of this seems counter intuitive to me? Maybe you could expand a little please?

"Stalled", to me, should be UN-loading the prop? When you "stall" a wing, it stops producing lift. If the prop blades stop producing lift (because they're stalled), what's left to load the engine? Or have I completely missed your point?

I alway thought the reason an engine turned higher rpms in the air was because air being force fed into the front of the prop - unloading it to a degree compared to having it just sitting there? For instance, this same engine/prop might slow down again when the plane goes vertical (assuming less than 3D power for a moment). This is because the blades are "stalling"?

The earlier comments regarding cooling at WOT on the ground - I agree with you if you're thinking of a fairly tightly cowled (possibly scale) setup. No argument. I was thinking more along the lines of a sport plane. Think Ugly Stick, with a totally exposed engine for instance? I would be scared to run a carb setting that might overheat an "open" engine running WOT on the ground... and many "loosely" cowled installs as well.

And yes, agreed beyond any doubt, ANY tuning done on the ground cannot be assumed to be best possible. That takes some flying....
Just me....
ahicks is online now  
Reply With Quote
Old 05-22-2012, 11:06 AM
  #5485
av8tor1977
 
av8tor1977's Avatar
 
Join Date: May 2003
Location: Tucson, AZ
Posts: 6,938
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Any time an airfoil is stalled or nearly so, it is also creating lots of drag. This loads the engine. As the airflow begins to go through the propellor as the airplane accelerates, the blades experience an effective reduction of angle of attack, unstall, and produce less drag. Hence the engine speeds up due to having less load on it. I have seen this on the ground while taching engines too. Point the airplane into the wind, and your tach reading at full throttle will increase. And of course I have experienced it as a pilot of full size airplanes as well. This is why a "constant speed" prop, which is cockpit adjustable, is very effective. You can flatten or lower, the pitch of the prop for takeoff, which makes the prop much more efficient starting from a stop and at low speeds. Then, when in cruise, you increase the pitch, making the prop more effective at that speed. The key is that the airflow through the prop changes the effective angle of attack of the blades.

As far as the cooling angle, I understand your point. But even an uncowled sport airplane engine can get too warm with extended full throttle running on the ground. They need the added airflow from being in flight to be safe at extended full throttle usage. The center area of the prop makes a poor cooling fan.

More on cooling here: http://www.rcuniverse.com/forum/m_11071695/tm.htm

Hope this helps,
AV8TOR
av8tor1977 is offline  
Reply With Quote
Old 05-22-2012, 11:26 AM
  #5486
acdii
 
Join Date: Jan 2011
Location: Capron, IL
Posts: 6,273
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Cooling problem solved, just use one of these www.northerntool.com/shop/tools/product_200448627_200448627
acdii is offline  
Reply With Quote
Old 05-22-2012, 04:02 PM
  #5487
ahicks
 
Join Date: Aug 2008
Location: Waterford, Mi/Citrus Springs, Fl
Posts: 3,457
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: av8tor1977

Any time an airfoil is stalled or nearly so, it is also creating lots of drag. This loads the engine. As the airflow begins to go through the propellor as the airplane accelerates, the blades experience an effective reduction of angle of attack, unstall, and produce less drag. Hence the engine speeds up due to having less load on it. I have seen this on the ground while taching engines too. Point the airplane into the wind, and your tach reading at full throttle will increase. And of course I have experienced it as a pilot of full size airplanes as well. This is why a ''constant speed'' prop, which is cockpit adjustable, is very effective. You can flatten or lower, the pitch of the prop for takeoff, which makes the prop much more efficient starting from a stop and at low speeds. Then, when in cruise, you increase the pitch, making the prop more effective at that speed. The key is that the airflow through the prop changes the effective angle of attack of the blades.

As far as the cooling angle, I understand your point. But even an uncowled sport airplane engine can get too warm with extended full throttle running on the ground. They need the added airflow from being in flight to be safe at extended full throttle usage. The center area of the prop makes a poor cooling fan.

More on cooling here: http://www.rcuniverse.com/forum/m_11071695/tm.htm

Hope this helps,
AV8TOR
Ok, I was thinking "stalled" as in past tense - after it's stalled. I've got what you're saying now. Thanks
ahicks is online now  
Reply With Quote
Old 05-23-2012, 11:04 AM
  #5488
Falcon32
 
Falcon32's Avatar
 
Join Date: May 2006
Location: Neath, UNITED KINGDOM
Posts: 332
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

HI Guys
Thinking of changing the ignition on my DLE20 (No4).
It's not so easy to find a replacement here in the UK.
Is this the one I need ? RCEXL Model A-01

Thanks
Falcon32 is offline  
Reply With Quote
Old 05-23-2012, 02:41 PM
  #5489
DwightMann
 
Join Date: Sep 2004
Location: Mohave Valley, AZ
Posts: 168
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)


Quote:
ORIGINAL: ahicks


Quote:
ORIGINAL: av8tor1977

Any time an airfoil is stalled or nearly so, it is also creating lots of drag. This loads the engine. As the airflow begins to go through the propellor as the airplane accelerates, the blades experience an effective reduction of angle of attack, unstall, and produce less drag. Hence the engine speeds up due to having less load on it. I have seen this on the ground while taching engines too. Point the airplane into the wind, and your tach reading at full throttle will increase. And of course I have experienced it as a pilot of full size airplanes as well. This is why a ''constant speed'' prop, which is cockpit adjustable, is very effective. You can flatten or lower, the pitch of the prop for takeoff, which makes the prop much more efficient starting from a stop and at low speeds. Then, when in cruise, you increase the pitch, making the prop more effective at that speed. The key is that the airflow through the prop changes the effective angle of attack of the blades.

As far as the cooling angle, I understand your point. But even an uncowled sport airplane engine can get too warm with extended full throttle running on the ground. They need the added airflow from being in flight to be safe at extended full throttle usage. The center area of the prop makes a poor cooling fan.

More on cooling here: http://www.rcuniverse.com/forum/m_11071695/tm.htm

Hope this helps,
AV8TOR
Ok, I was thinking ''stalled'' as in past tense - after it's stalled. I've got what you're saying now. Thanks
Compare a spin to a vertical dive. The plane is stalled during a spin and the speed is much slower than durin a dive which is not stalled
DwightMann is offline  
Reply With Quote
Old 06-01-2012, 03:57 AM
  #5490
WindGap
 
Join Date: Aug 2010
Location: Irmo, SC
Posts: 228
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

How much more power can be gained from updating muffler?
WindGap is offline  
Reply With Quote
Old 06-01-2012, 08:26 AM
  #5491
captinjohn
 
Join Date: Jan 2002
Location: Hesperia Michigan, MI
Posts: 12,873
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Best update...is a Mintor 22cc engine. Nice ! Capt,n
captinjohn is offline  
Reply With Quote
Old 06-01-2012, 09:52 AM
  #5492
mach2
 
mach2's Avatar
 
Join Date: Nov 2011
Location: bakersfield, CA
Posts: 1,107
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

What is this mintor 22cc you have been mentioning? Are you getting paid for advertisement? haha.

Im gonna look them up. Ive heard about them a couple times now. Im in the market for a 30cc. Im pretty set on the DLE30 since I know its good. But Why not keep the options open....

Jeremy
mach2 is offline  
Reply With Quote
Old 06-01-2012, 10:11 AM
  #5493
w8ye
Moderator
 
w8ye's Avatar
 
Join Date: Dec 2001
Location: Shelby, OH
Posts: 37,525
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Here is a source

http://www.chiefaircraft.com/min-22.html
w8ye is online now  
Reply With Quote
Old 06-06-2012, 04:50 AM
  #5494
acdii
 
Join Date: Jan 2011
Location: Capron, IL
Posts: 6,273
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

Well after months of sitting in the shop, I finally put the wing on my Deweyville, fired up the engine, which started right up and ran good, and took off.  Once it was in the air, the exhaust sound was more scale like than I had imagined, and at 1/3rd throttle an overhead pass sounded and looked like a real plane. It was awesome.  I do need to downsize the prop though, it pulled the plane well, and it wasn't more power than I had thought it would be when at WOT, but the prop did strike the ground when I landed, and it was a good landing, but since I land on grass, all it takes is a slight bump for the blade to strike, so going to find a 3 blade MAS K to replace the 16X8 MAS K I put on it for my maiden.  Good thing too, the XOAR would have most likely snapped, and that would have been $15 down the drain, especially considering it wasnt for this plane, but the P-51.  Going to give the 15x7x3 a try and see how it does.  Who knows, maybe it will work good and when I finish the Stang, I will make it an A model and run the 3 blade on it.
acdii is offline  
Reply With Quote
Old 06-06-2012, 06:32 AM
  #5495
DwightMann
 
Join Date: Sep 2004
Location: Mohave Valley, AZ
Posts: 168
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

A 15x7x3 may not be enough to load the engine. I had a 16x8x3 on an Aeroworks Extra 260 and was getting 8900 RPM
DwightMann is offline  
Reply With Quote
Old 06-06-2012, 07:31 AM
  #5496
acdii
 
Join Date: Jan 2011
Location: Capron, IL
Posts: 6,273
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

First page shows it was tested,

MA K-series 15x6 3-blade[/b] 13.0lbs @ 9100 rpm

Should work on my plane, haven't weighed it, but it is no lightweight.
acdii is offline  
Reply With Quote
Old 06-06-2012, 02:16 PM
  #5497
mach2
 
mach2's Avatar
 
Join Date: Nov 2011
Location: bakersfield, CA
Posts: 1,107
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

How much performance is lost by going to a three or even a four blade prop?

I think putting the scale prop on planes like an Extra or an Edge would look cool. But its so common to see the models with two blade props, it almost makes me forget that the real ones use three blades.....

I know on the full scale planes, three blades are more effecient, so Is that why large scale models sometimes have 3 blades? And what's the effeciency cuttoff?

mach2 is offline  
Reply With Quote
Old 06-06-2012, 03:08 PM
  #5498
DwightMann
 
Join Date: Sep 2004
Location: Mohave Valley, AZ
Posts: 168
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

WWII planes had high horsepower and needed a lot of prop. Ground clearance was a problem. The Corsair went to a Gull Wing to help with ground clearance. Another issue is that a 9' diameter prop at 2500 rpm will have the tip exceeding the speed of sound. This would cause a lot of stress on the prop and loose efficiency. The multi blade props were used more as a sacrafice than to get more out of the engine, they just made a bigger engine to compensate
DwightMann is offline  
Reply With Quote
Old 06-06-2012, 03:15 PM
  #5499
acdii
 
Join Date: Jan 2011
Location: Capron, IL
Posts: 6,273
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

For the Dewey, performance isn't much of a concern   I just need the ground clearance. A 2 blade 15" would definitely overspeed the motor.
acdii is offline  
Reply With Quote
Old 06-06-2012, 04:21 PM
  #5500
kerwin50
 
Join Date: Oct 2006
Location: winston, MO
Posts: 1,378
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: NEW DLE 20cc Gasser! (Data & Links 1st Post)

I don't like the muffler set up on the mintor.
I wish they would change the ign on the dle
kerwin50 is offline  
Reply With Quote


Thread Tools
Search this Thread
Display Modes

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



All times are GMT -8. The time now is 04:14 AM.