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[jaymac]

Are there  gearboxes to run 2 motors of one prop can't find owt on google

[Geoff]

I'm not sure but be aware gearboxes tend to be either very noisy or very expensive, or both! If you need to link two engines to one shaft maybe use one as direct drive and the other using a toothed belt as this would give quieter running.


It begs the question why as it probably won't be as efficient as using one larger motor. If you are very lucky you may be able to find a motor that has an extended shaft at the rear and then you can couple them in line.


Good luck


Cheers


Geoff

[ChrisF]

Geoff

The heading is opposite to the question and the former makes more sense.

Chris

[Umi_Ryuzuki]

Mack Products 
 However you want it, two motors to one drive, or one motor to two drives.
.

http://www.mackproductsrc.com/power%20units%20-%20q.htm

[jaymac]

Sorry about that don't know whether I'm coming or going. Actually maybe it need not be a gearbox just something that splits the drive to  2 props
Thanks

[Plastic - RIP]

It's much, much easier - and probably cheaper to use a separate motor on each propshaft - no complicated belts or gears.   

[jaymac]

Hi Plastic yes I know I already have that but the existing motors are very badly aligned . Their Beds  would be very difficult to remove and so locating  further fore or aft not possible.I though to fit a single motor  between them easier than chiselling the beds out hence my query. I think I will have to consider that though
Thanks

[roycv]

Hi all, just like to make the case for sticking motors in place with bathroom sealant!  Motors only have to be held in place and resist rotational forces, I have been doing it for years and had no problems. 

A few months ago I found I had fitted an old motor that turned out to be giving interference and it came away with a little help with a X-acto chisel blade leaving no residual glue.
A few years ago I had to use a hammer and chisel to remove a good motor from a redundant/donated hull.  There really is no need to use P 38 to hold a motor in place.
regards
Roy

[Plastic - RIP]

Hi all, just like to make the case for sticking motors in place with bathroom sealant!  Motors only have to be held in place and resist rotational forces, I have been doing it for years and had no problems. 
regards
Roy

I'm a second for bathroom sealant - shock absorbing and self aligning.   

[chas]

Me too for most models. The oldest is about 20 years old and still fine. The exceptions are the obvious ones like brushless.
  Re the twin props, we don't know what type of model it is, but if it's a ship or similar performing model why not a twin pulley drive?
2 drive pulleys on the motor shaft, and 2 drive belts to a pulley on each shaft. I did this about 30 years ago and it worked well.
Charles

[Ralph]

  Re the twin props, we don't know what type of model it is, but if it's a ship or similar performing model why not a twin pulley drive?
2 drive pulleys on the motor shaft, and 2 drive belts to a pulley on each shaft. I did this about 30 years ago and it worked well.
Charles

Belt drive is probably the easiest and quietest solution but it means both props turn the same way which could affect steering (I made that mistake with a flat bottomed hull - no problem going to starboard but port took twice as far to make a turn.  Changing to contra-rotating props sorted things).  A simple gear box with the motor pinion directly driving a gear mounted on one shaft and driving the other shaft via an idler would give contra-rotating.  Motor might need to be mounted off centre to fit the idler gear in.
Ralph

[GG]

Jaymac,
          At the risk of being accused of "self-promotion", I'd suggest you look at an item on the use of Pulleys in the Tutorial section of this site.
The can be an easy, quiet and reliable means of driving two propellers from one motor.
Glynn Guest

[jaymac]

Thanks Glyn just what I need to read though might have a go at chiselling out first

[jaymac]

Well removing the existing bed would  be too risky and belts and pulleys too fiddly for my knackered fingers. Toying with maybe moving the motors forward and extending the shafts app 3''.Thought maybe one  rigid coupling and one flexible the shafts are 2mm .Is there a better way to extend other than new shafts

[chas]

What is the model?  Advice on here might be more precise if we knew.

[jaymac]

Italeri S-100

[Geoff]

If you are looking to extend the shafts by 3 inches then just use a lay shaft with two Huco couplings (or the equivalent) for each shaft as this will take care of any small misalignment. I do this on a lot of my models and it works very well.


Cheers


Geoff

[jaymac]

Finally extended the shafts leaving  existing brackets in place (Immovable) . Got new mfa brackets for the 380 size motors. As I can only screw to the brackets when I have the bracket in my hand. There is very little space beneath the base plate of the bracket or I would  glue wood and then screw the bracket down. As  it has to be removable . Did toy with maybe Velcro . Anything else anyone suggest, several previously mentioned bath sealant would that work.
Thanks

[Plastic - RIP]

I always use silicone to fix my motors - if there's too much space, just silicone a packing piece underneath first.        If too little space, dump the bracket and just silicone the bare motor to the floor of the hull.

[jaymac]

Thanks  Plastic   just any bathroom sealant or particular type

[Plastic - RIP]

I've found ordinary high-strength bathroom silicone just fine - but the vinegar will rust the outside of the motor can slightly (just a cosmetic annoyance) so recently I've been using a polyurethane automotive sealant instead - this stuff - https://www.ebay.co.uk/itm/SOUDAL-HIGH-STRENGHT-POLYURETHANE-ADHESIVE-SEALANT-KOI-FISH-POND-310ml-40FC/143786910139?hash=item217a5e21bb:g:vBwAAMXQ8OdRJst6

This stuff literally sticks sh** to blankets!!      It's also flexible so isn't affected by vibration.

[jaymac]

Thanks

[roycv]

Hi all when using the large tubes of sealant that require a plunger to operate them, just leave the nozzle full of unused sealant.  If left for a while it will go off but is easy to remove.  If you clear the nozzle and the top surface dries off inside the tube, you might as well throw it away.
Merry Christmas
Roy

[Plastic - RIP]

Hi all when using the large tubes of sealant that require a plunger to operate them, just leave the nozzle full of unused sealant.  If left for a while it will go off but is easy to remove.  If you clear the nozzle and the top surface dries off inside the tube, you might as well throw it away.
Merry Christmas
Roy

I always push a nail into the end of the nozzle to seal the end to reduce the contact with air.      I also try to stack jobs so I get to use as much of the tube in one go - to get the maximum value before it goes in the bin. 

[Barney Magrew]

If you're worried about the acetic acid content on some of the sealants, Dow Corning do a sealant specifically for use on metals, electronics etc.