ESM Dornier DO 335
02-19-2013, 05:39 AM
#476
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RE: ESM Dornier DO 335
ORIGINAL: grossy2
I'm using a Wike PDS and Twin Sync. All powered by dual A123 batterys. These I placed up front next to the engine.
I'm using a Wike PDS and Twin Sync. All powered by dual A123 batterys. These I placed up front next to the engine.
Why use a twin sync on a pusher twin with dissimilar engines/propellers???
I cant for the life of me think of a reason...
02-19-2013, 03:37 PM
#477
RE: ESM Dornier DO 335
Here's some pics of the progress today. I now have the rear motor installed, rear cowl and spinner all in place. Motor again is a turnigy g60 400kv spinning a 16x10x3 MAS PUSHER prop. Spinner is from Dave Brown with pusher prop cuts along with a lightened back plate.
The esc shown is a SS 100 amp....the motor wires have been lengthened considerably with fat high capacity wiring. Even still....I will have to use a long extension on the battery side. So...because of that....I ordered a Tamjets 3x 180UF 63v plug-n-play capacitor. That will get placed at the point from the current esc battery lead and then the additonal wiring will go forward to the battery itself.
You can see in the pics that the esc sits right on the big fat belly airscoop so it will stay plenty cool.
Also note the rear air vents I cut out and then glued screencover over. This will allow air to vent out of the fuse rather easily. An additional bonus of this location....since the rear prop is a pusher....its going to help suck air out of the fuse and blow it behind the plane.
I may have the rear motor limited to 50% throttle just so its not drawing a whole lot of juice.....but...will need to see overall performance first with both at 100% to see if I can do that. No dounts that I can do so with a 65cc up front...but....always good to do tests
The esc shown is a SS 100 amp....the motor wires have been lengthened considerably with fat high capacity wiring. Even still....I will have to use a long extension on the battery side. So...because of that....I ordered a Tamjets 3x 180UF 63v plug-n-play capacitor. That will get placed at the point from the current esc battery lead and then the additonal wiring will go forward to the battery itself.
You can see in the pics that the esc sits right on the big fat belly airscoop so it will stay plenty cool.
Also note the rear air vents I cut out and then glued screencover over. This will allow air to vent out of the fuse rather easily. An additional bonus of this location....since the rear prop is a pusher....its going to help suck air out of the fuse and blow it behind the plane.
I may have the rear motor limited to 50% throttle just so its not drawing a whole lot of juice.....but...will need to see overall performance first with both at 100% to see if I can do that. No dounts that I can do so with a 65cc up front...but....always good to do tests
02-19-2013, 04:23 PM
#479
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RE: ESM Dornier DO 335
You might ask around, but the prop is on backward.... The markings go forward regardless of whether its a pusher or normal rotation...
You knew that, but are just seeing whos lurking, eh???
I love this bird. It is HARD not to bite off on one from Tomas... There was one at the LHS for sale at @ $2,800... LOL wishful thinking! Didnt even have Sierras in it.
Im following. Cant wait for the maiden!
ORIGINAL: kahloq
Here's some pics of the progress today. I now have the rear motor installed, rear cowl and spinner all in place. Motor again is a turnigy g60 400kv spinning a 16x10x3 MAS PUSHER prop. Spinner is from Dave Brown with pusher prop cuts along with a lightened back plate.
The esc shown is a SS 100 amp....the motor wires have been lengthened considerably with fat high capacity wiring. Even still....I will have to use a long extension on the battery side. So...because of that....I ordered a Tamjets 3x 180UF 63v plug-n-play capacitor. That will get placed at the point from the current esc battery lead and then the additonal wiring will go forward to the battery itself.
You can see in the pics that the esc sits right on the big fat belly airscoop so it will stay plenty cool.
Also note the rear air vents I cut out and then glued screencover over. This will allow air to vent out of the fuse rather easily. An additional bonus of this location....since the rear prop is a pusher....its going to help suck air out of the fuse and blow it behind the plane.
I may have the rear motor limited to 50% throttle just so its not drawing a whole lot of juice.....but...will need to see overall performance first with both at 100% to see if I can do that. No dounts that I can do so with a 65cc up front...but....always good to do tests
Here's some pics of the progress today. I now have the rear motor installed, rear cowl and spinner all in place. Motor again is a turnigy g60 400kv spinning a 16x10x3 MAS PUSHER prop. Spinner is from Dave Brown with pusher prop cuts along with a lightened back plate.
The esc shown is a SS 100 amp....the motor wires have been lengthened considerably with fat high capacity wiring. Even still....I will have to use a long extension on the battery side. So...because of that....I ordered a Tamjets 3x 180UF 63v plug-n-play capacitor. That will get placed at the point from the current esc battery lead and then the additonal wiring will go forward to the battery itself.
You can see in the pics that the esc sits right on the big fat belly airscoop so it will stay plenty cool.
Also note the rear air vents I cut out and then glued screencover over. This will allow air to vent out of the fuse rather easily. An additional bonus of this location....since the rear prop is a pusher....its going to help suck air out of the fuse and blow it behind the plane.
I may have the rear motor limited to 50% throttle just so its not drawing a whole lot of juice.....but...will need to see overall performance first with both at 100% to see if I can do that. No dounts that I can do so with a 65cc up front...but....always good to do tests
02-19-2013, 11:38 PM
#483
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RE: ESM Dornier DO 335
Hi Hellcat,
Ihaven't assembled mine yet, and only have the fixed gear it comes with, so Ihave measured a main gear leg and the wheel. It looks like the wing should be about 320 mm from the ground. That would be just over foot in Imperial units. Ipresume the height would work out similar with the retracts.
regards
John
Ihaven't assembled mine yet, and only have the fixed gear it comes with, so Ihave measured a main gear leg and the wheel. It looks like the wing should be about 320 mm from the ground. That would be just over foot in Imperial units. Ipresume the height would work out similar with the retracts.
regards
John
02-20-2013, 06:39 AM
#484
RE: ESM Dornier DO 335
ORIGINAL: hellcat56
kahlog
ta152
jimkron
anyone
can anyone tell me the distance fromt he bottom of the wing to the ground
just trying to find out how tall from the ground
Sounds like a lot of you guys have it on the wheels
how about a measurment?
kahlog
ta152
jimkron
anyone
can anyone tell me the distance fromt he bottom of the wing to the ground
just trying to find out how tall from the ground
Sounds like a lot of you guys have it on the wheels
how about a measurment?
02-20-2013, 06:40 AM
#485
RE: ESM Dornier DO 335
ORIGINAL: F82FAN
You might ask around, but the prop is on backward.... The markings go forward regardless of whether its a pusher or normal rotation...
You knew that, but are just seeing whos lurking, eh???
You might ask around, but the prop is on backward.... The markings go forward regardless of whether its a pusher or normal rotation...
You knew that, but are just seeing whos lurking, eh???
02-20-2013, 07:43 AM
#486
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RE: ESM Dornier DO 335
ok....
ORIGINAL: kahloq
Ummmm....actually, the prop is NOT on backwards. The markings always face AWAY from the front of the motor the prop is installed on. Its the direction the blades are canted that determines if pusher or tractor. The spinner was specifically cut for a pusher prop and the prop can only fit in it one way.
ORIGINAL: F82FAN
You might ask around, but the prop is on backward.... The markings go forward regardless of whether its a pusher or normal rotation...
You knew that, but are just seeing whos lurking, eh???
You might ask around, but the prop is on backward.... The markings go forward regardless of whether its a pusher or normal rotation...
You knew that, but are just seeing whos lurking, eh???
02-20-2013, 09:00 AM
#489
RE: ESM Dornier DO 335
ORIGINAL: vertical grimmace
Yep, backwards. Try running it. Is it Pushing air away from plane?
Yep, backwards. Try running it. Is it Pushing air away from plane?
The only reason why you'd have to mount a pusherprop on the TAIL of a plane with markings towards front of plane would be due to using an IC motor that mechanically only turns in one direction.
All the proof I need that its on correctt is that the spinner from dbproducts was specifically cut for pusher. The prop only fits in one way. The setup works as it should blowing air rearward frontm the TAIL. There is no argument to be had here. Seriously, some of u talk to me like I'm Forest Gump. Did you people even bother looking at the close up pic with spinner on? Jeez ppl, it can't be mounted any other way.
02-20-2013, 11:30 AM
#492
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RE: ESM Dornier DO 335
If a propellor is on backwards it will still push air in the correct direction, but with less efficiency. Look at a normal propellor mounted on the front of the plane as usual. The rounded edge of the airfoil is at the front and the sharp edge is at the back. It will of course turn anticlockwise. If you turn it over on the shaft, the helix angle is still the same but the airfoil will be operating inverted. It will work but at lower efficiency.
If we mount the same propellor at the back as a pusher, it will still need the rounded edge towards the front of the plane, and to work properly will need to turn clockwise. (as seen from the rear) This is no problem with electrics, just swap any two motor leads. With an IC engine you would generally need internal modifications, so you want a pusher prop. This has the opposite helix angle. As with the prop at the front, it can go on the shaft two ways. If it is on the wrong way it will still push in the right direction, but with less efficiency.
So my little foamy DO 335 uses two ordinary tractor props, but the pusher motor is running "reversed", eg if you look from the front of the plane both motors are turning anticlockwise. My ESM DO 335 is going to have IC engines, so the rear prop will need to be a pusher. But in both cases, all the props need to be installed with the rounded leading edge of the blade towards the front of the plane.
From a torque reaction point of view, it is nicer if the two props counterrotate, so one would need to be a pusher. But for our purposes it probably does not matter much.
John
If we mount the same propellor at the back as a pusher, it will still need the rounded edge towards the front of the plane, and to work properly will need to turn clockwise. (as seen from the rear) This is no problem with electrics, just swap any two motor leads. With an IC engine you would generally need internal modifications, so you want a pusher prop. This has the opposite helix angle. As with the prop at the front, it can go on the shaft two ways. If it is on the wrong way it will still push in the right direction, but with less efficiency.
So my little foamy DO 335 uses two ordinary tractor props, but the pusher motor is running "reversed", eg if you look from the front of the plane both motors are turning anticlockwise. My ESM DO 335 is going to have IC engines, so the rear prop will need to be a pusher. But in both cases, all the props need to be installed with the rounded leading edge of the blade towards the front of the plane.
From a torque reaction point of view, it is nicer if the two props counterrotate, so one would need to be a pusher. But for our purposes it probably does not matter much.
John
02-20-2013, 12:53 PM
#494
RE: ESM Dornier DO 335
Possibly a blonde girl moment on my part. I'll take a look at it tomorrow when I get home from work road trip. If the prop won't fit any other way, regardless of whether its on right or backwards, ill be stuck with the way it is. I'm not going to spend another $75+ on a spinner if its not cut right just to make an efficiency improvement(if that would be the case) on a motor I'm not relying on for thrust production anyway.
02-20-2013, 01:09 PM
#495
RE: ESM Dornier DO 335
ORIGINAL: kahloq
Possibly a blonde girl moment on my part. I'll take a look at it tomorrow when I get home from work road trip. If the prop won't fit any other way, regardless of whether its on right or backwards, ill be stuck with the way it is. I'm not going to spend another $75+ on a spinner if its not cut right just to make an efficiency improvement(if that would be the case) on a motor I'm not relying on for thrust production anyway.
Possibly a blonde girl moment on my part. I'll take a look at it tomorrow when I get home from work road trip. If the prop won't fit any other way, regardless of whether its on right or backwards, ill be stuck with the way it is. I'm not going to spend another $75+ on a spinner if its not cut right just to make an efficiency improvement(if that would be the case) on a motor I'm not relying on for thrust production anyway.
Do any of you remember on some of the old .049 planes, you could turn the prop around to fly for the first flights to lower performance? The prop still created thrust, just not as much. The same thing is happening here.
02-20-2013, 01:24 PM
#496
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RE: ESM Dornier DO 335
The spinner is actually the right one, they are cut with a reasonable amount of clearance and will still clear if you reverse the prop. At least mine did when I initially put the prop on wrong last night when playing with mine.
Incidently the backing plate on these spinners looks a bit heavy to me, for something that is to go at the back of the plane over a metre behind the CoG. It might get a bit of a skim on the lathe.
John
Incidently the backing plate on these spinners looks a bit heavy to me, for something that is to go at the back of the plane over a metre behind the CoG. It might get a bit of a skim on the lathe.
John
02-20-2013, 03:57 PM
#498
Senior Member
RE: ESM Dornier DO 335
ORIGINAL: F82FAN
Just a Q....
Why use a twin sync on a pusher twin with dissimilar engines/propellers???
I cant for the life of me think of a reason...
ORIGINAL: grossy2
I'm using a Wike PDS and Twin Sync. All powered by dual A123 batterys. These I placed up front next to the engine.
I'm using a Wike PDS and Twin Sync. All powered by dual A123 batterys. These I placed up front next to the engine.
Why use a twin sync on a pusher twin with dissimilar engines/propellers???
I cant for the life of me think of a reason...
Cheers
Grossy
02-20-2013, 08:24 PM
#499
RE: ESM Dornier DO 335
ORIGINAL: Ameisenbar
If a propellor is on backwards it will still push air in the correct direction, but with less efficiency. Look at a normal propellor mounted on the front of the plane as usual. The rounded edge of the airfoil is at the front and the sharp edge is at the back. It will of course turn anticlockwise. If you turn it over on the shaft, the helix angle is still the same but the airfoil will be operating inverted. It will work but at lower efficiency.
If we mount the same propellor at the back as a pusher, it will still need the rounded edge towards the front of the plane, and to work properly will need to turn clockwise. (as seen from the rear) This is no problem with electrics, just swap any two motor leads. With an IC engine you would generally need internal modifications, so you want a pusher prop. This has the opposite helix angle. As with the prop at the front, it can go on the shaft two ways. If it is on the wrong way it will still push in the right direction, but with less efficiency.
So my little foamy DO 335 uses two ordinary tractor props, but the pusher motor is running ''reversed'', eg if you look from the front of the plane both motors are turning anticlockwise. My ESM DO 335 is going to have IC engines, so the rear prop will need to be a pusher. But in both cases, all the props need to be installed with the rounded leading edge of the blade towards the front of the plane.
From a torque reaction point of view, it is nicer if the two props counterrotate, so one would need to be a pusher. But for our purposes it probably does not matter much.
John
If a propellor is on backwards it will still push air in the correct direction, but with less efficiency. Look at a normal propellor mounted on the front of the plane as usual. The rounded edge of the airfoil is at the front and the sharp edge is at the back. It will of course turn anticlockwise. If you turn it over on the shaft, the helix angle is still the same but the airfoil will be operating inverted. It will work but at lower efficiency.
If we mount the same propellor at the back as a pusher, it will still need the rounded edge towards the front of the plane, and to work properly will need to turn clockwise. (as seen from the rear) This is no problem with electrics, just swap any two motor leads. With an IC engine you would generally need internal modifications, so you want a pusher prop. This has the opposite helix angle. As with the prop at the front, it can go on the shaft two ways. If it is on the wrong way it will still push in the right direction, but with less efficiency.
So my little foamy DO 335 uses two ordinary tractor props, but the pusher motor is running ''reversed'', eg if you look from the front of the plane both motors are turning anticlockwise. My ESM DO 335 is going to have IC engines, so the rear prop will need to be a pusher. But in both cases, all the props need to be installed with the rounded leading edge of the blade towards the front of the plane.
From a torque reaction point of view, it is nicer if the two props counterrotate, so one would need to be a pusher. But for our purposes it probably does not matter much.
John
We flew my ESM 335 with Eflite 160 on back and front with Zoar 20x10 props. I'm doing this from memory. The back prop was a pusher. The two motors counter rotated. We tried using two tractors spinning in the same direction but the torque made the plane less fun to fly. The roll rate left was different than the right roll rate. No huge deal but you had to "stay on it". Bummer cuz the pushers are hard to find and sometimes have to be special ordered.
02-21-2013, 08:02 AM
#500
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RE: ESM Dornier DO 335
ORIGINAL: kahloq
Yeah except this is one ''fan'' that'll cut your hand off if your not careful.
ORIGINAL: vertical grimmace
Looks like a this old house episode on how to install a ceiling fan! lol
Looks like a this old house episode on how to install a ceiling fan! lol