Gremlin help
#26

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From: St John IN
Guys I started a gremlin build this past winter. We had 6 guys build them. We have 20+ gremlins in the club. Last night 4 of us got into it, i had a mid air with a coraplast plane, Stayed in the air then cut his ribbon. Took a 4 inch chunk out of the leading edge. Will have it repaired by noon tomarrow. I sheet and vacume bag my wings. 1/16 on top and 3/32 on the bottom.
ED
ED
#27
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From: Southbridge,
MA
Seems like overkill and dead weight. Part of the beauty of the design is the flexing of the wing. With the pine leading edges they can do ok in midairs and as long as you apply the fiber reinforced tape as instructed for the wing reinforcement, they tend to flex and not break even on cartwheels. We're coming in at about 3 pounds. how heavy are the sheeted wings? (sounds like Q500 sheeting BTW). lighter planes will out turn heavier ones
Jim
Jim
#28

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From: Bethlehem,
PA
I have been interested in Gremlins for a while, and there is just no easy way to say it. They are impossible to find in plan form. I scratch build most of my craft. I also like using electric. In this post I noticed you have seen an electric version. Can you get me there?
Thx
Thx
#29
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From: Southbridge,
MA
it's a solid foam wing and a PVC fuselage, there isn't any need for a plan. R/C Modeler did a set of plans for the construction article and they got them WRONG. They made the tip template too small. I have found the December 1992 RCM online for sale and picked them up in the past, you could go that route if you want. The kits are still available at the 1992 price, just the S&H has gone up since UPS is killing me on shipping. I will point our local Electric Gremlin guy at the topic and he can reply also. We had a Contest in NH yesterday and he was very competitive with his brushless 3 cell version
#30
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From: Southbridge,
MA
Here is the configuration that he suggests:
And he was running a 10x10 prop with that and claimed it tested out at 85% efficiency (quoting from memory)
Jim lets get this configuration up on your website as the Electric Stock
class configuration. "3 cells Lipo for stock and 4 cells and up for open".
This is the config I used at the meet on Sunday.
Motor: 1110KV Scorpion SII-3020-1110
Battery: 3 Cell 3300mAh 40C TURNIGY 3300
Motor Controller 60A TURNIGY or Castle Creation
If we just limit the battery to 3 cells it will be easier to monitor and it
won't be as limiting to the new people interested in going electric to
selecting or finding what they think is a better solution.
class configuration. "3 cells Lipo for stock and 4 cells and up for open".
This is the config I used at the meet on Sunday.
Motor: 1110KV Scorpion SII-3020-1110
Battery: 3 Cell 3300mAh 40C TURNIGY 3300
Motor Controller 60A TURNIGY or Castle Creation
If we just limit the battery to 3 cells it will be easier to monitor and it
won't be as limiting to the new people interested in going electric to
selecting or finding what they think is a better solution.
#31
I have attached all technical info for all those who whish to kill by electrons.
Good luck and happy hunting.
Steve the Electric Guy
Comparison - Gremlin 3 Scorpion SII-3020-1110
600ft above Sea Level, 29.92inHg, 57°F
Motor Scorpion SII-3020-1110
Motor Constant (rpm/V) 1110
No Load Current (A) 2.08
Armature Resistance (Ohms) 0.016
Battery TURNIGY 3300
Series Cell Count 3
Parallel Cell Count 1
Cell Capacity (mAh) 3300
Pack Capacity (mAh) 3300
Cell Voltage (V) 3.7
Pack Voltage (V) 11.1
Cell Resistance (Ohms) 0.0051
Pack Resistance (Ohms) 0.0153
Speed Control (ESC) Castle Creations Phoenix 60
Resistance (Ohms) 0.0012
Maximum Current (A) 60
Number of ESCs 1
Drive System APC 10x8-10
Gear Ratio 1.00:1
Propeller (in x in) 10x10
Series Motors 1
Parallel Motors 1
Number of Propellers 1
Blades per Propeller 2
Airframe Gremlin 3Cell
Wing Span (in) 48
Wing Area (sq.in) 578
Total Weight (oz) 46.7
Static Predictions
Current (A) 49.7
Motor Voltage (V) 10.3
Input Power (W) 510.9
Input Power Loading (W/lb) 175.0
Power Loss (W) 72.6
Motor/Gearbox Output (W) 438.3
Output Power Loading (W/lb) 150.1
Motor/Gearbox Efficiency (%) 85.8
Shaft Efficiency (%) 79.5
Motor RPM 10217
Propeller RPM 10217
Static Thrust (oz) 53.0
Pitch Speed (mph) 96.8
Run Time (min:sec) 3:59
Flight Predictions
Stall Speed (mph) 20
Optimal Flight Speed (mph) 28
Throttle for Optimal (%) 39
Motor Temp at Optimal (°F) 78
Hands-off Speed (mph) 42
Throttle for Hands-off (%) 52
Motor Temp Hands-off (°F) 89
Best Rate of Climb (ft/min) 2416
Rate of Sink (ft/min) -355
Good luck and happy hunting.
Steve the Electric Guy
Comparison - Gremlin 3 Scorpion SII-3020-1110
600ft above Sea Level, 29.92inHg, 57°F
Motor Scorpion SII-3020-1110
Motor Constant (rpm/V) 1110
No Load Current (A) 2.08
Armature Resistance (Ohms) 0.016
Battery TURNIGY 3300
Series Cell Count 3
Parallel Cell Count 1
Cell Capacity (mAh) 3300
Pack Capacity (mAh) 3300
Cell Voltage (V) 3.7
Pack Voltage (V) 11.1
Cell Resistance (Ohms) 0.0051
Pack Resistance (Ohms) 0.0153
Speed Control (ESC) Castle Creations Phoenix 60
Resistance (Ohms) 0.0012
Maximum Current (A) 60
Number of ESCs 1
Drive System APC 10x8-10
Gear Ratio 1.00:1
Propeller (in x in) 10x10
Series Motors 1
Parallel Motors 1
Number of Propellers 1
Blades per Propeller 2
Airframe Gremlin 3Cell
Wing Span (in) 48
Wing Area (sq.in) 578
Total Weight (oz) 46.7
Static Predictions
Current (A) 49.7
Motor Voltage (V) 10.3
Input Power (W) 510.9
Input Power Loading (W/lb) 175.0
Power Loss (W) 72.6
Motor/Gearbox Output (W) 438.3
Output Power Loading (W/lb) 150.1
Motor/Gearbox Efficiency (%) 85.8
Shaft Efficiency (%) 79.5
Motor RPM 10217
Propeller RPM 10217
Static Thrust (oz) 53.0
Pitch Speed (mph) 96.8
Run Time (min:sec) 3:59
Flight Predictions
Stall Speed (mph) 20
Optimal Flight Speed (mph) 28
Throttle for Optimal (%) 39
Motor Temp at Optimal (°F) 78
Hands-off Speed (mph) 42
Throttle for Hands-off (%) 52
Motor Temp Hands-off (°F) 89
Best Rate of Climb (ft/min) 2416
Rate of Sink (ft/min) -355
#32

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From: Townsend,
MA
Steve's Gremlin is very fast and powerful ( but he still didn't cut me
) with this motor set up but he has put a lot of work into it to prevent flutter. ( it's smoooooth! ) But what "Steve the elecric guy" doesn't know is "Bob the nitro guy" is working on the cheapest elecric Gremlin known to mankind for you low budget guys. Since I don't have all the cool meters and stuff I am just going to guess and see what happens. I think it will be around 400 watts. I am using a Tower Pro trash can outrunner with a 3 cell. I should be able to keep it under 3lbs no problem. It will be mild for stock class which should be good for the newbie and still be cheap enough to afford mid air losses to your equipment.
I'll keep you posted
) with this motor set up but he has put a lot of work into it to prevent flutter. ( it's smoooooth! ) But what "Steve the elecric guy" doesn't know is "Bob the nitro guy" is working on the cheapest elecric Gremlin known to mankind for you low budget guys. Since I don't have all the cool meters and stuff I am just going to guess and see what happens. I think it will be around 400 watts. I am using a Tower Pro trash can outrunner with a 3 cell. I should be able to keep it under 3lbs no problem. It will be mild for stock class which should be good for the newbie and still be cheap enough to afford mid air losses to your equipment.I'll keep you posted
#33
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From: Southbridge,
MA
Well, I still haven't seen Steve's 3 cell version fly yet. What you flew against was the 4-5 cell version I believe. We need a session out there together to have some fun now that we all have some spare time.
#34

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From: Townsend,
MA
Steve put together a mean Gremlin![>:] I was running from him. Maybe I'm wrong but I thought it was the 3 cell version.
I just picked up some props for the "cheap" gremlin. I also need a couple wing kits from you Jim.
I just picked up some props for the "cheap" gremlin. I also need a couple wing kits from you Jim.
#35
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From: Southbridge,
MA
I haven't seen his 3 cell version fly yet. He wasn't able to make it this past weekend either. He was trying to cheapen it and make it more comparable to the Norvels. How that I have a .32 powered one back flying I can concentrate on an electric
#36

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From: Townsend,
MA
OK I managed to fly it tonight with a 10X5 prop and a 3 cell 2200 turnigy lipo. ( it was all I had) It launched good and had power that I say would equal a LA 25. Not a powerhouse but not bad either. I will have to try a 4 cell I think that will make it nice.
I built it with everthing that comes in the kit and it wieghed in at 2lbs. 11 oz. That was with low temp econocote not the packing tape.
The motor is from Hobby city - http://www.hobbycity.com/hobbycity/s...idProduct=5113
TowerPro Brushless Outrunner 3015-7 1000kv / 470W
HobbyKing 40A BlueSeries Brushless Speed Controller
http://www.hobbycity.com/hobbycity/s...dProduct=11430
I built it with everthing that comes in the kit and it wieghed in at 2lbs. 11 oz. That was with low temp econocote not the packing tape.
The motor is from Hobby city - http://www.hobbycity.com/hobbycity/s...idProduct=5113
TowerPro Brushless Outrunner 3015-7 1000kv / 470W
HobbyKing 40A BlueSeries Brushless Speed Controller
http://www.hobbycity.com/hobbycity/s...dProduct=11430
#41

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From: Townsend,
MA
I have a 10X7 so I will give that a try. I know it's cheap but I wanted to see if I could get a cheap enough set up that newbie's would try it and also if you have a midair that is a total loss ( rare) you won't go home to sad[
]
]
#43

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From: Townsend,
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Hey ! don't be bad mouthing my motor[>:] HA already applied my ca
The screw issue seems to be solved because they put long and short screws in my package. Not that should be a problem HELLO ! when the srews are to long cut them!. You need to watch the test video about the motor they address those problems
The screw issue seems to be solved because they put long and short screws in my package. Not that should be a problem HELLO ! when the srews are to long cut them!. You need to watch the test video about the motor they address those problems
#45

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From: Cincinnati,
OH
Hi Guys,
I caught the word Gremlin in the forums list and came right here.
I have built a Gremlin and she flys very well. Some time ago I ordered two more sets of everything, but haven't opened the box yet. My first Gremlin is still in good flying condition (no one does combat at my club) after 5 years.
If anyone still wants copies of the planes, building photos and rules of engagment I have them, let me know.
I caught the word Gremlin in the forums list and came right here.
I have built a Gremlin and she flys very well. Some time ago I ordered two more sets of everything, but haven't opened the box yet. My first Gremlin is still in good flying condition (no one does combat at my club) after 5 years.
If anyone still wants copies of the planes, building photos and rules of engagment I have them, let me know.
#46
We are getting that knack for combat back here in the North East... The electric Gremlins are catching on and guys are getting competitive once again. This is my second season and I love it. You should fire up the old Gremlins and generate some interest in the aerial blood sport back in your neck of the woods.
Steve
Steve
#47
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From: Southbridge,
MA
I agree with Steve, get out there and fly with a streamer and you'll even get trainers to chase you. The best way to generate interest is to let people fly one. Or get a buddy to build one of the other kits and chase each other. Pretty soon you'll have the interest of others when they see the fun you are having.
I would appreciate if you didn't distribute photocopies of the instructions. I do retain the intellectual property rights to them. There are building websites around including [link]http://www.snhflyingeagles.org/pdf_files/GremlinConstructionPhotos.pdf[/link] which I link to from my website but the instructions and updates were a lot of personal effort and go beyond the original RCM article
I would appreciate if you didn't distribute photocopies of the instructions. I do retain the intellectual property rights to them. There are building websites around including [link]http://www.snhflyingeagles.org/pdf_files/GremlinConstructionPhotos.pdf[/link] which I link to from my website but the instructions and updates were a lot of personal effort and go beyond the original RCM article
#48

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From: Cincinnati,
OH
Jim,
I apologize, I certanly didn't mean to cause any loss to you. I was trying to be helpful...that's all. I will, in the future, keep Gremlin planes to myself.
By the way, thanks for all your hard work over the years. Mike
I apologize, I certanly didn't mean to cause any loss to you. I was trying to be helpful...that's all. I will, in the future, keep Gremlin planes to myself.
By the way, thanks for all your hard work over the years. Mike
#49
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From: Southbridge,
MA
no problem. I just had someone duplicate the instructions years ago and then sell inferior hand cut cores with them but since he had left my contact information on them, I had to deal with his irate customers. I have no problem with people creating their own kits, I just want to retain the instructions, that is my value added. People have made kits based on the RCM article lots of times. I did redo the instructions a couple of years ago to include construction photos so I hope people are finding them better now.
Get out there and fly and have a ball. Most people are afraid to try the plane because they think it will be hard to fly because it looks so different but 2 minutes of stick time makes them reconsider. And I meant what i said about flying with a streamer. Even the trainers can't resist a couple of passes at it
Get out there and fly and have a ball. Most people are afraid to try the plane because they think it will be hard to fly because it looks so different but 2 minutes of stick time makes them reconsider. And I meant what i said about flying with a streamer. Even the trainers can't resist a couple of passes at it


