Scatch Building FT Simple Cub - 2213 motor too short

[pjmills81]

Hello,

I am scratch building the FT Simple Cub and bought the MT2213-935kv motor today as recommended in the power pack B. When I have my power pod installed it is fitting correctly with the internal structure and the firewall sits flush with the top foam piece but when the motor is attached it is too far back and the prop is touching the front of the fuselage.

Am I doing something wrong or is this motor/shaft not long enough?

Please see attached photo.

Thank you

 

[daxian]

hi pj....
did the motor come with an x mount ?? mine did (2212 1400 kv) and just fits nicely....yours seems to mount straight to the firewall....

 

[pjmills81]

Thanks for your reply daxian. Nope it didn't come with an x mount.

 

[Ken Myers]

I'm curious as to why no one from Flite Test has chosen to respond, also why they chose a multi-rotor motor with no motor mount.
The fix if pretty obvious, but why it has to be fixed is not.
In general, it has been pretty quiet around here regarding the Simple Cub recently.

 

[mrjdstewart]

they are normally very close, but not that close. not sure what happened. grab a couple washers and you will be fine, or just trim a little off the nose.

laters,

me

 

[checkerboardflyer]

I bought both the Old Fogey and the Old Speedster along with one PowerPack B and one PowerPack C. The C was for the Old Speedster. Made a mistake. Started building the Speedster but using the B. Had the exact same problem; prop was touching the front of the fuselage. The pic attached shows that the B is shorter than the C. I was ready to use standoffs until I realized my mistake.

 

[mrjdstewart]

i have multiple Simple Cubs and they are split between the B and C packs. both motors fit for me.

laters,

me

 

[Ken Myers]

The 'fix' for the motor 'coming up short' is quite easy.
Cut a piece of foam board the width of the power pod and about 1/4" wide. Remove the power pod. Pin the extension piece to the bottom of the back of the power pod. Slide the power pod back in. It will now stop a 1/4" farther forward. Put two new holes through the power pod, using the holes in the fuselage as a guide. Reinsert the skewers that hold the power pod in. Done. No cutting of the front end of the fuselage or adding spacers to the motor. It will also benefit the balance as well.

 

[Forster]

The new power pack motor is shorter than the old one (even with an X-mount installed) but the plans were not adapted. You can fix this several ways. The easiest is to just install the prop when you push the mount in and skewer it into place where it fits (you could also add a spacer between the motor and firewall or other options like a washer behind the prop or trimming the nose fairing a bit). This might be a good discussion to have on the Unofficial Simple Cub Page as you could easily add length to the upper nose panel on a scratch build model.

 

[Hai-Lee]

I do a number of repairs, gas to electric conversions and a fair amount of design and prototyping of RC model aircraft and the problem you face is quite common.

It seems that electric motors are getting smaller, lighter and more powerful than ever before. I have struck where replacement motors based upon similar performance are shorter and lighter PLUS electric motors seem to be lighter and shorter than the electric equivalent. When designing for a model to support a number of different power setups to suit different experience levels the problem occurs yet again.

My usual fix for the different distances between firewall and prop line is to use a plywood donut shaped disk. The plywood is selected to give the correct spacing and the donut hole can be big or even omitted to aid in proper balance. The donut spacer is screwed to the existing firewall and the electric motor mounted to the plywood disk. This allows the process to be reversed easily if required. Where weight needs to be added to achieve balance the hold in the donut can be capped with a thin additional layer of thin ply, after the fitting of the ballast in the donut hole.

Done properly it can be quick to fit, easy to balance, (a secure place for nose weight if required), and fully reversible if required.

Just what works for me!

Have fun!