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[tomo55]

Looking to mount a motor in a ASRL .Is there away to mount it on expanding foam to deaden the noise?
Thanks Chris

[nhp651]

don't laugh, but i always mount mine on dollops of blue tack.

always worked fine and easy to extract when me boats sink.lol

[Shipmate60]

Or self extract if motor gets hot!!!

Bob

[stallspeed]

The stuff changes shape all the time and would prevent motor cooling.

You can get antivibration material from RS components and stick adhesive backed foam into the hull

I have a cassette motor mounted onto a bracket with anti-vibratin grommets.(high-density rubber)
The screws don't make contact with the bracket. Shaft coupling is by pulley.

[nhp651]

i never have the problem of big motors getting hot, the slow scale speeds i sale at., and as it was for an air sea rescue launch, they weren't particularly fast. that was the reason for posting bluetack as a solution
mind you i can understand your comments for fast electrics....now that would be hairy.lol

[DickyD]

To cut down on noise buy a decent motor. 

[Proteus]

i never have the problem of big motors getting hot, the slow scale speeds i sale at., and as it was for an air sea rescue launch, they weren't particularly fast. that was the reason for posting bluetack as a solution
mind you i can understand your comments for fast electrics....now that would be hairy.lol

they weren't particularly fast. Are you thinking of the right boats, because the ones I have pictures of are going reasonably fast

Proteus

[tonyH]

Try fixing the motor mount to the hull with a decent dollop of silicone bath sealant - worked very well in an old Deans Motor Gun Boat I had.

Tony

[nhp651]

no proteus, they weren't the ones i was thinking about, emmmmmmm

[tomo55]

thanks for the suggestions ,the bath sealant seems a good way to try.
do you hold the motor in place on the bed of sealant(elastic bands) or does it stick in place unaided?
Thanks again Chris

[wombat]

Remember, when mounting the motor, the mount onto the hull has to resist the maximum torque the drivetrain is liely to see, preferably strong enough to resist a stall of the motor - if not, chances are that if you foul the prop you could tear the motor off its mount.

Wom

[FullLeatherJacket]

Sorry if it seems like the "elephant in the room" question, but what type of motor are you wishing to mount and in what type of hull (i.e. size, material etc)? Bear in mind that Model Slipway's RTTL is a different matter from a four foot Aerokits clone.
These details might just be important....indulge me!
FLJ

[derekwarner]

Hi...it can sometimes be the reverse  ...if the motor + mounting has any potential for vibration...this is the attracted into the hull as a resonance & is literally in a BOOM box & amplified

An alternate is a much more substantial motor mounting eliminating the vibration & hence the resonance is absorbed into the hull & structure & partially negated  ....Derek

[MCAT]

You can also use the sound pads , used on car doors self adhesive sheet can be trimmed to size gives a nice padded look in the boat  

worked on a tug I built as there was so much space left over I swear there was an echo in there. any shop that supplies car parts
for old mini's adds a bit of ballast too.

[John W E]

hello all

Just a question - what type of electric motors are you using?  Because if its the electric motors which are causing vibration, then, I would bin them.  I think there is something seriously wrong with them - as in, something out of balance on the armature or the commy - or a bent shaft.    The majority of electric motors I have bought/used run quite silently.   

The majority of problems come from either:

a) a cheap, out of line coupling

or

b) a bent prop shaft

You should be able to mount the motor securely in the hull; without the need for any insulation or sound proofing material - as I believe one has already said, all the thrust and tork end up being transferred from the propeller eventually ending up at the motor mount and then being transferred to the hull.   Any weak spots between the motor mount and the hull is when you encounter problems where the motor tries to leave the hull.

Im attaching a pic of the three Graupner Speed 600s mounted in the 63ft whaleback running on 8.4 volts - the problem I had, was that I had originally fitted a 'cheapo' red coupling in there and I found it was of line - go for the black couplings. 

aye
john

[Proteus]

One problem I have noticed more than once when people have vibration problems is that they have the wrong coupling size there are so many close sizes but not close enough I have seen one person had to use a bolt as the grub screw was not long enough , it should be a reasonable fit wit he grub screw out with no slop .

Proteus