Atlantic Society of Radio Controlled Modellers
https://www.asrcm.ns.ca/cgi-bin/yabb2/YaBB.pl
Atlantic Society of Radio Control Modellers >> Current Projects >> Mentor - best way to stiffen the motor mount?
https://www.asrcm.ns.ca/cgi-bin/yabb2/YaBB.pl?num=1304106981

Message started by speedbird on Apr 29th, 2011 at 4:56pm

Title: Mentor - best way to stiffen the motor mount?
Post by speedbird on Apr 29th, 2011 at 4:56pm
I am just finishing a Mentor - had to wait a week to get my hands unglued!
a 25 fits nicely in it, running with a 13x8 wooden prop to begin with...
Heard about the vibration...and some of the various fixes...
Any pictures?

My word, only two screws to hold the motor/prop to the fuse.  4 others (non-attached - acting as adjustable spacers).  The motor/prop assy rocks in pitch but it is stiff about the yaw axis

I would be grateful for any ideas & pictures?
Brian


Title: Re: Mentor - best way to stiffen the motor mount?
Post by astroflyer on Apr 29th, 2011 at 5:23pm
no pictures.  but jon fibreglassed the whole compartment around the motor.

he then test flew the plane and checked the motor plate alignment and when satisfied fibreglassed or glued that in place as well.

the mentor is noted for vibration in the motor mount especially when over powered.  "overpowered" means different things to different people.  just ask jon.  ;D

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Joe Di Profio on May 2nd, 2011 at 9:34am
Liquified viagra could work.....Grundy may have some to spare.  ;) :D ;)

Title: Re: Mentor - best way to stiffen the motor mount?
Post by sugarpops on May 2nd, 2011 at 7:00pm
Hey Joe......Bill did have some liquified viagra, but he spilled it all over his fingers, he keeps poking himself......

Sugar 8-)

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Joe Di Profio on May 3rd, 2011 at 11:10am
That gotta hurt..;)

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Bill G on May 3rd, 2011 at 3:29pm
Not as embarrassing as a stiff finger lasting over four hours…. 

This is the last time I’m taking any of Cousin Harold’s advice.   :o

Title: Re: Mentor - best way to stiffen the motor mount?
Post by speedbird on May 9th, 2011 at 7:04pm
here is one solution
mentor_mount.jpg (56 KB | 419 )

Title: Re: Mentor - best way to stiffen the motor mount?
Post by speedbird on May 9th, 2011 at 7:11pm
this is better and inexpensive
Small Parts CNC
interesting web site and company
http://www.smallpartscnc.com/funcub%20universal.html

you should paste this into a browser to see the image
nice CNC part
less than 20$ including shipping....
Brian

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Rob on May 9th, 2011 at 7:54pm
I have had good success "Beefing Up" the Mentor Motor Mount. I used some thick plywood 3/16" I made a slot in the nose and slid it down in front of the two longitudinal plastic stock mounts. As you can see I also used lots of 30 minute epoxy laced with Micro Balloons. This way the motor is installed using the stock steel mounts held on by Blind nuts through the new plywood firewall. Don't be afraid of using lots of reinforcement to this area,as this motor has tons of torque and will twist the nose of the aircraft,causing a Big Vibration and can shake loose of not well supported.  ;D

Rob
Mentor-3.jpg (45 KB | 432 )

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Rob on May 9th, 2011 at 7:57pm
Another mod I used with Great success is Flaps !
The mentor does not need them, however it makes for a super dive at a lower speed to get it down in a hurry.......
Mentor-2.jpg (31 KB | 415 )

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Rob on May 9th, 2011 at 7:59pm
I used a super sharp Zona Saw......and some Robart round hinges in a "V" configuration.........
The Mentor is a Good Aircraft,to play with on land or water.....it has a wide speed envelope and good flying characteristics.

Rob
Mentor-1.jpg (50 KB | 420 )

Title: Re: Mentor - best way to stiffen the motor mount?
Post by astroflyer on May 9th, 2011 at 11:41pm
Nice paint rob!






Title: Re: Mentor - best way to stiffen the motor mount?
Post by speedbird on May 10th, 2011 at 6:34pm
I like Robs Firwall mount
Using this you do not have to use a collet on a "reversed motor"
it solves the rocking with a four point attachment?


Title: Re: Mentor - best way to stiffen the motor mount?
Post by speedbird on May 10th, 2011 at 6:38pm
Here are some motor facts
using a 13 x 8 prop overheats the 25 size motor with a 40C 4S

using a prop sizing program i get an 11 x 7 as a good match with 50A max.  This with a 60A plush ESC and a 5A UBEC.

the Neodym 25 is a nice fit.
with the 13 x 8 prop I was getting 56A and 768W static and enough thrust to say "I had to hang on to the tail for all I worth".  But hot at the end of the run.
I will use the temp gauge on the next run

Just about to try an 11 x 7 for the numbers

Title: Re: Mentor - best way to stiffen the motor mount?
Post by JON BOY on May 10th, 2011 at 10:13pm
Brian, like I said before just use some fiberglass cloth and some resin. This takes just two evenings.Top and sides of the engin area one night, and bottom the next night.Test the plane to make sure that everything is ok then glue in the motor mount and you are good to go. Mine has almost 1400 watts, 15x8 prop, 5 cell lipo,around 70 amps full throttle and held together just fine. I think that you are making too much out of a simple problem. All this takes about 1 hour.... I should know, as this is my second mentor. My first lasted just 4 flights. :'( Dont ask. Wonderful flying airplane though. Looking forward to my new one.

Title: Re: Mentor - best way to stiffen the motor mount?
Post by Fingers on May 11th, 2011 at 9:41am
or a small pair of vise grips will work just fine .....

Title: Re: Mentor - best way to stiffen the motor mount?
Post by speedbird on Jun 20th, 2011 at 9:10pm
flies nicely with CNC mount and 4S 25 motor
wing does need stiffeners a la Jon Boy
Until then
just gentle flights


Atlantic Society of Radio Controlled Modellers » Powered by YaBB 2.5.2!
YaBB Forum Software © 2000-2024. All Rights Reserved.