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[Steven.T]

Hi Jan,
thanks for your reply, I understand what you are saying, however, with my motor secured, this is how the coupling looks:



Which is why I think it keeps slipping off, it's basically getting pulled off?




However, if I prop the motor up from the rear, it makes the coupling look like this, should I do something to make it permanently like this?:



Cheers,
Steven

[lakesidebob]

You need to lessen that angle as much as possible,but even if you take away the motor mount and can hopefully secure the motor, it looks like there will still be an angle on it...As the earlier post says the shaft and motor should be exactly in line.Can you alter the prop shaft angle?Good Luck with that one.Bob.

[Steven.T]

I could alter the angle, but it would mean cutting the propshaft out from where it's held on the outside of the hull, which may not be easy, then re-positioning it inside aswell. Looking at it I don't think I fancy trying it, and I don't think the angle will be that much better than propping the back of the motor up as best I can,should be easier aswell I think?
Cheers,
Steven

[lakesidebob]

Thing to do Steven is secure the motor as in the 2nd picture,put the gear in and try it on the water.This is your main priority.If the tube falls off or vibration etc or generally 'no good',then i'm afraid.. ....with patience the tube will come out and you can then get it properly in-line and all will be sorted.No way could you see it working as in the 1st picture.Again,all the best.Bob.

[Steven.T]

Cheers Bob, will hook it all up at the weekend and give it a spin 

[rem2007]

I had a similiar problem with mine Steve. I molded some modelling clay in the motor mount to get the angle of the motor to sit true to the prop shaft and used wire to secure the motor in as it gets a bit warm and melts the rubber band they suggest, then put a proper universal coupling in as the rubber coupling kept slipping off, try this it worked week for mine. Almost classified as a fast electric.
Robert

[GAZOU]

 
if you draw back the engine 1 inch  you'll have a pus open angle.
You will not need to change the angle of the motor shaft
Buy a real coupling, you will not be bothered
your piece of rubber is of the breast, it is not reliable
 

[pompebled]

Hi Steven,

Oh dear...

The rubber coupler will only work if motor and propshaft are alligned perfectly, this is easily acheived by taking a longer shaft.
With a longer shaft, the motor can slide forward until the allignment is 100%.

You'll need to make another motormount (preferably without using rubber bands, even household silicone would be preferable), but that's no problem for a modelbuilder. You can even use 3 mm thick styrene card to make a motormount, just don't block the cooling slots on the shaft side of the motor.

If a longer shaft isn't an option, you could go for a coupler like this:
http://www.robbe.de/navy-kardan-44.html?___store=en&___from_store=de
Available in the UK from Cornwall boats:
http://www.cornwallmodelboats.co.uk/acatalog/robbe-coupling-assemblies.html

This coupler is long enough to 'emulate' a longer shaft and also requires a new motormount.
Don't be tempted to use the coupler to compensate for the odd angles in the first picture, make sure things are alligned properly!

Regards, Jan.

[Steven.T]

Thanks again for the replies guys, I will try some of the ideas and see what I can do.
Jan, Unfortunately the motor mount is vac formed as part of the internal tray, so removing it would leave a big gap where it was. I'll try some other options first but will bear this in mind.
Hopefully I will have some good news tomorrow if I get time to look at it!
Cheers for the help everyone!
Steven

[Netleyned]

The internal tray with the motor mount in the right location
should allow the motor to align with the shaft in the right
location/angle.
The motor shaft and the prop shaft should align or you
will suffer vibration/overheating and more current drain.

Ned

[pompebled]

Unfortunately the motor mount is vac formed as part of the internal tray, so removing it would leave a big gap where it was.

Hi Steven,

That's not really an issue, a cutting disk in a Dremel will take care of the plastic part and a couple of pieces of styrene sheet, cut to fit, will cover the gaps (or not, covering the gaps would be cosmetically, as there's the bottom underneath, isn't it?).

Having reasonable access should be more of a concern when fitting a new motormount.

Regards, Jan.

[lakesidebob]

Strange one this.Were you aware of this situation when you first started the kit 6 years ago?Is it the original motor?The angle of the shaft in the previous picture from outside looks 'ok' as if it should line up with the motor/mount,no problem,yet doesn't.Surely,the motor mount has to be dremelled out and the motor lowered or the shaft re-aligned? Trying to help.Bob.

[warspite]

Would moving the motor as far back as possible and then link to the prop shaft with either a single or double coupling be better, from the picture the prop shaft entering appears to be a little 'low' and may explain why the angle is so sharp, or it's designed for a motor with a smaller external diameter?.

[Circlip]

Or a motor with an offset drive?
 
   If you need to move the motor forwards (Towards the front or Bow) you could connect with one of these :-

http://miponline.com/store/page24.html

   Regards  Ian.

[warspite]

or move the motor further away vertically and use a geared setup or a vee belt drive, adjusting the tension by packing out the motor from underneath, just a thought

[Circlip]

No space underneath without extending the shaft.
 
   Would think the original build has been deviated from.
 
  Regards  Ian.

[Model_Slipway]

It does appear that the propshaft entering is too low. The hole should be 7-10mm from the bottom in order to lign up with the motor shaft.
Regards
Jackie

[Steven.T]

Ah right cheers Jackie, I see where I have gone wrong. It doesn't actually say about the 7-10mm in the instructions, just to use the skeg as a guide for the hole.
Right, looks like I'll have to remove the propshaft. Should be able to do it by taking a hacksaw in between the skeg and the shaft, that should free it off, and re work that bit then!
D'oh!
Cheers,
Steven


EDIT: I tell a lie! just had a look at the boat now, looking at the hole that comes through into the tray. By the looks of it, the glue that was holding the prop up into the correct position has given way somehow, thus letting the prop sit lower. I've just jacked it up by sliding some plasticard inderneath, and it now sits within a couple of mm of the shaft! Think I'll drop a spot of glue on it and try that first!

[lakesidebob]

Wonder if you've stored the boat for six years in a hot summer loft,shaft sitting on hard surface...not on a stand... things on top of it...weight...the glue has softened,shaft shifted...maybe this is what's happened?.At least you're getting there.The motor and shaft have to line up exactly,then it will work...Good Luck.Bob.

[Steven.T]

Right, well. I've managed to line the shaft up with the motor by lifting the prop to the top of the hole and wedging it there and gluing it. But (and that's a big but!) the tube has now got a very slight bend in it, in between the hull entrance point and the end of the tube inside. Obviously this isn't right, and makes the propeller wobble when it's running, and when dropping the prop back in it stops at this point. Looks like the whole thing is coming out after all...
Looking at the hull outside, the prop-shaft and skeg aren't quite central, so I'm going to have to remove it, and re-drill the hole bit further over unfortunately!
Oh well!
Steven

[Tug-Kenny RIP]

It's not that bad. We've all had alignment problems but not as much advise as you've received.

Imagine how proud you'll be when you line up the new one.   

Cheers

Ken

[Steven.T]

Cheers Ken.
New prop has been ordered from Model Slipway, might aswell renew it, more for my piece of mind I think!
I think half the problem is this is my first working model boat build, I've never had to align the prop before!


Cheers
Steven

[Steven.T]

The new prop and bits arrived today from Model Slipway, (Thanks for the helps there guys!) so I proceeded to rip the old prop out. Thankfully it has come out without too much damage, the skeg is still intact and nothing else is damaged so it all looks good so far!
One question I do have, does it matter what angle the Prop comes out of the boat at? I mean, obviously 90 degrees would be no good, but is there a certain angle, or just whatever lines up with the motor best?
Cheers,
Steven

[pompebled]

Hi Steven,

If it's a planing hull, 7° is regarded as the limit, less angle is better, but not always possible without resorting to a (much) longer propshaft and extensive surgery.

Regards, Jan.

[lakesidebob]

Good luck with this Steven,you have persevered with this and should get it right now.Go carefully and think about it...post pics? Lots of interest as well.Bob.