How Do I Mount My Outrunner Motor ?

[CHELLIE]

Originally Posted by LectricPlane

Here is one I just put together for my PZ Spit.
Pics below.

12mm Balsa rod push formed into a 10mm hole in the ply firewall, the rest is reasonably clear in the pics, I think.

The through mounted balsa standoffs make it easy to set the angle and length.

Can't wait to get it in the air!

Hi LectricPlane You probably already did this, but i just wanted to suggest using a drop or two of thin CA into the screw hole on the wood mount that holds the x motor mount, to make the threads stronger, Take care, Chellie

[WWIIP38]

Another Newbie question here!
Putting a Turnigy outrunner brushless in a ChargerRC foamie. Prop adapter mounts on bell and motor is mounted 'backwards'. Is it OK to cut off the motor shaft that sticks out what is now the back?

[CHELLIE]

Originally Posted by WWIIP38

Another Newbie question here!
Putting a Turnigy outrunner brushless in a ChargerRC foamie. Prop adapter mounts on bell and motor is mounted 'backwards'. Is it OK to cut off the motor shaft that sticks out what is now the back?

http://www.headsuprc.com/servlet/the...r-Mount/Detail

[CHELLIE]

just glue a 3/8" X 3/8" basswood into the plane, give the motor a little down thrust, about 3 to 5 degrees, no right or left thrust is needed on a profile plane, but a little down thrust helps to stabilize the plane alot, if the fit is a little loose, wrap some masking tape once around the wood stick, leave about 1/16" hanging over, so the tape does not bunch up on you as you slide the motor mount on, hope that helps, Chellie

[CHELLIE]

Welcome to Wattflyers WWIIP38

[WWIIP38]

Chellie,
Thank you very much for your fast and informative answers!
WWIIP38

[CHELLIE]

Originally Posted by WWIIP38

Chellie,
Thank you very much for your fast and informative answers!
WWIIP38

Your very Welcome Take care and have fun, Chellie

[SunDevilPilot]

Here is my electric Retrofit. The plane, during the construction process, was converted from glow to electric. Not wanting to remove the glow installation blind nuts for fear of destroying the firewall I went around them. The mount has about 3 degrees of right and 1.5 degrees of down thrust built in.

SunDevilPilot

[CHELLIE]

Originally Posted by SunDevilPilot

Here is my electric Retrofit. The plane, during the construction process, was converted from glow to electric. Not wanting to remove the glow installation blind nuts for fear of destroying the firewall I went around them. The mount has about 3 degrees of right and 1.5 degrees of down thrust built in.

SunDevilPilot

Wow, thats a nice clean motor mount,good job, Take care, Chellie

[ezra]

Thank You this was very helpful

[EDFrules]

This is what happens when you put a great pilot on the sticks. Downside of a rolling harrier loop-SNAP! And he got it down in one piece without breaking the prop! Mount showed no signs of fatigue during pre-flights. Gyroscopic loads during hard 3D flying cannot be underestimated. Already e-mailed Hacker about this. Doesn't take an engineering degree to figure out the failure point. Suggested they leave out the last row of lightening holes and make the rear half of the mount with some thicker stock. In the mean time I'll be adding some aluminum struts from the firewall to the motor mount end so this won't occur again. I was originally going to fab a carbon plate mount with aluminum angle thru-bolted, my hunch was right. Live and learn. Least this didn't happen at next weeks air show during the noon time demo-Doooh! Fortunately my LHS has the A60 mounts in stock so I can repair it and get it airworthy. A little kevlar for the cowl and some struts and she'll be back in business.

[Destroyer of airplanes]

I have no idea what "Gyroscopic Loads" are but your problem appears to be metal fatigue induced by high frequency vibration. Most likely the motor or propeller is slightly out of balance.

The rusted hardware tells me that set up had been in there a while. Do you have any idea how many hours this set up lasted before the failure?





Paul

[EDFrules]

Gyroscopic loads come from 34lbs of thrust generated by a 25 x 12 balanced Xoar prop. I never put a prop on unless I check it first and being a big prop it would be readily apparent right away if it was unbalanced. When you do snap rolls, tumbles and rolling harriers etc. this puts the plane on an off center position relative the direction the plane is going. In effect it twists the heck out of the mount. That mount was on a total of about 20 flights so it was reletively new. The hardware got a little wet flying in the rain a while back so it was a little corroded. High frequency vibration would be mild compared to what we put our planes thru. If you fly hard 3D you need a good solid mount, straight line sport flying puts very little strain on mounts comparitively. I'll get some video posted of this plane in action soon and you'll start to understand how much stress is put on these planes. Here's a vid of a DA 150 gas powered plane flown by my friend for reference. Watch about the middle of the video when he comes out of a knife edge circle and starts to point harrier roll. The servos, motor mount are hating life at this point. As soon as the rolling harrier loops start I can quarantee you the mount is strained to the max. But that's what it's all about-3D fun! Here's another video of a small 3D plane that my bud Blake lays into and I've had to redo the firewall a time or two just from the smack down he lays on it. Towards the middle of the vid you can hear the plane making some roaring noises and it's not coming from the prop...

Jason

RC Gas Airplane Demo: Roar& Soar 2007 Blake Hilson

RC Electric Airplane-Shulman Aviation Exhila

[Destroyer of airplanes]

Jason,

That is about the best flying and the hardest I have ever seen. As a scale guy I've never broken anything in the air due to any type of flight loads. All my breakage had some form of ground involvement. I do tend to over build and beef things up. Here is picture of a .60 size motor mount I built. I used 1/4x28 threaded rod. Is I was going to use this type of mount on a large 3D I'd probably use six standoff legs. I don't think there is any way my mount would move but with six legs there is a smaller area for the flight loads to induce a bending moment to fatigue the parts..

Again I very much enjoyed your videos.

Paul

[EDFrules]

Come to think of it, I never broke anything in the air flying scale either. As soon as I started to 3D though...broken wing tubes, cracked fuses, motor mounts, lost some aileron hardware. But I've learned for 3D- go heavy duty on hardware like RC truck ball swivels and carbon tube/titanium tips for pushrods,phenolic/carbon plate or aluminum for horns/arms that kind of thing. I've learned the hard way, if I don't do it right the first time there might not be a second time!
Solid looking mount you got there. I'll try and shoot some pics of my mods for reference in case anyone else runs into this situation...or Blake flies your plane!

Regards,
Jason
Here's another vid of Blake putting the hurt on his 35% Extra 260 and he was just playing around here:
http://www.youtube.com/watch?v=kjqI5OrwbJ4

[CHELLIE]

Originally Posted by EDFrules

This is what happens when you put a great pilot on the sticks. Downside of a rolling harrier loop-SNAP! And he got it down in one piece without breaking the prop! Mount showed no signs of fatigue during pre-flights. Gyroscopic loads during hard 3D flying cannot be underestimated. Already e-mailed Hacker about this. Doesn't take an engineering degree to figure out the failure point. Suggested they leave out the last row of lightening holes and make the rear half of the mount with some thicker stock. In the mean time I'll be adding some aluminum struts from the firewall to the motor mount end so this won't occur again. I was originally going to fab a carbon plate mount with aluminum angle thru-bolted, my hunch was right. Live and learn. Least this didn't happen at next weeks air show during the noon time demo-Doooh! Fortunately my LHS has the A60 mounts in stock so I can repair it and get it airworthy. A little kevlar for the cowl and some struts and she'll be back in business.

( my hunch was right. Live and learn ) , Always go with your Hunch Its always right Last time i failed to go With My Hunch, I Got a Speeding ticket a Woman Pissed me off, when she pulled out in front of me, almost caused a crash, I blasted the horn, and was able to go around her, then she speeds up and cuts in front of me and slows down, Can anyone say, ROAD RAGE, I went around her, speed up to loose this A Hole, and got a ticket, clocked on lazer at 50 in a 35MPH zone, was i pissed off, Its all my Fault, because a Hunch told me to go another way to work and i did not listen to my gut feeling Live and learn, My Ticket cost more than your Motor mount Take care, Chellie

[EDFrules]

Actually 50 bucks is less than the total damage if I have to buy another cowl($50 right there) and the mount plus some alum. You got off easy! My last speeding ticket was $135-ouch. But I finally got my revenge on another road A-hole(he was from Massachusetts does that make him a Mass-hole?) by baiting him. He was riding my bumper honking and flashing lights so I got parallel with the car next to me so he couldn't pass and waited for the next bend in the highway(where there were 10 staties setting a speed trap I knew about-haha!) and then at the right moment sped up and let him fly past=right into their radar guns! Gave him a nice wave as I drove past while the statie was pulling him over-felt good too! On a lighter note, I no longer feel the need to speed, I let the other "rabbits" attract the attention of the cops. I love watching them race by only to see the flashing blues pulling them over a few miles down the road. Lesson learned...

[CHELLIE]

Hmmmm I thought this was a interesting motor mount, from HugoW

[EDFrules]

He saw my old Unfuntana thread with mount. PVC works OK but some brands will deform after a while. Simple and lightweight but weighed a lot less than the stock Himaxx mount that came with my motor. And you can bevel it easily for thrust angle. Also forgot one of my Zafiro 3D test motors. Basic aluminum standoffs.

[CHELLIE]

Originally Posted by EDFrules

He saw my old Unfuntana thread with mount. PVC works OK but some brands will deform after a while. Simple and lightweight but weighed a lot less than the stock Himaxx stock that came with my motor. And you can bevel it easily for thrust angle. Also forgot one of my Zafiro 3D test motors. Basic aluminum standoffs.

Those Motor mounts look great, I am getting some ideas here too for my build, Thank You For Sharing, Chellie

[EDFrules]

When it comes to mounting motors there's always more than one way to skin that proverbial cat. Just limited by your imagination. And of course using the correct materials to keep it strong and lite. In my case I try to focus on structural integrity first then see how lite I can make it. I've also found a magic solution for keeping my larger planes in one piece-marine epoxy! It's a 2 part epoxy thats so thick you can stand a metal putty knife up straight in it and it won't fall over! Kind of heavy but it's only used on the landing gear plate area,firewall and wing tube spots. Just make a small fillet of it around the joints and it will not fail. The surrounding areas may fail but the joints won't. I fixed several 35 and 40% sized planes and haven't seen any failures thus far. Watched on 40% I fixed have the motor cut out in a hover and dropped right on the landing gear, not a crack! And the second time it cut out from about 30 feet up and pancaked down on the gear. Cracked the carbon LG but not the landing gear mount! Righteous stuff. Good luck on your projects and keep 'em flyin'!

Jason

[EDFrules]

Found some light aluminum angle struts at our local surplus store(cool place-has a flying saucer sticking out of it and missiles hanging from the rafters!). This sucker ain't goin' no where now! If it does it will be in a pile of balsa/plywood! Think it only added 1.2oz total=not a bad weight sacrifice to help save the plane next time.

[CHELLIE]

Stand off motor mount on Firemanbills 1/4 scale GP Shoestring nitro to E Power Plane, nice job Bill.

http://www.wattflyer.com/forums/showthread.php?t=44741

[Neogenesis]

There is one option I haven't seen here yet. How to mount a 50-65 270kv outrunner to a profile. Specifically I'm working on converting a OMP 67" Fusion. I've had to cut the old hardwood glow rails out to make room for the outrunner, and at this point am thinking of basically fitting a firewall in to mount the motor to. Using some triangle stock to reinforce and some angle aluminum to make sure it doesn't go anywhere. Anyone one else ever converted a profile?

Thanks,

Scott

[SunDevilPilot]

Here is another method of outrunner mounting. In this case the Hacker A30-12L has the drive shaft exiting the other side of the motor. Stock configuration for Hacker but opposite that of E-Flight.

SunDevilPilot