What is it? Prather?

[David Bryant]

Located this custom fabricated Octura "Swift-Switch" engine mount, was packed away in a box. The Swift-Switch "insert" portion (engine-mount platform) is missing from these images. I'm showing the "base" portion, and comparing to the conventional Octura 5-60 rigid mount.

Prather produced a limited quantity of these mounts for the Piranha outrigger kit to reinforce structural integrity. A number of racers were experiencing cracked crankcases, especially using the larger displacement engines (K&B .67's/.80's, etc.,...). Transferred forces caused by engine torque was responsible for "levering" the sponson bracket (aluminum "Wing Ding's") directly into the (stock) Octura rigid mount, causing the mount to flex. Resulting in excess stress to the crankcase. This was more of a unique issue with the Piranha- being a hollow epoxy fibre-glass fuselage design. The wood frame design of the Wing Ding hulls incorporated two bulkheads in the engine compartment.

The Prather mount incorporated a .125in thick aluminum plate TIG-welded to the forward (milled) edge of the Octura mount. Essentially an aluminum "Bulkhead". The side mounting surfaces were cleaned (milled) off. The finished mount, and aluminum sponson brackets, were then anodized a grey color (included in latter kit production).

The aluminum plate has to be milled open to provide proper clearance of rear portion of engine.

 

[Scott Miller]

I have one very close to finished it is for a 45 i know the mounts are not correct I can not find the hard mount

Gary send me a pm I think I have this engine mount.

 

[David Bryant]

I have one very close to finished it is for a 45 i know the mounts are not correct I can not find the hard mount

Which engine are you planning to use?

I was lucky, just recently came across a brand-new Prather aluminum motor mount- milled and drilled/tapped to fit Picco 45. These are similiar to the original Octura aluminum mounts. They are heavier than current mounts but function well in these older outrigger designs like the Wing Ding and Prather Piranha. The solid aluminum provides more structural support to prevent flexing (into engine crankcase) caused by engine torque.

I have had 7 wing dings over the years the wing ding was one of my first riggers bought in 79 this is one that did not get finished it was started by Mike Hallam not sure I am going to run it but I am going to finish it this year if you have the hard mount and think it will fit I am interested I would like to run a vac 45 but this would just be a fun run boat as there is not much nitro running in my dist. so any good 45 would do

Thanks

If you can, measure the engine compartment/fuselage width to comfirm whether it's 4in or 5in wide.

I would actually consider going with a .21/3.5cc marine engine (CMB .21VAC, Nova Rossi 21, Picco P21-R) if it's a Wing Ding 40 kit, and using a .45/7.5cc marine engine (CMB 45VAC, Nova Rossi 46, Picco P45-R, AA 45) in a Wing Ding 60. I think these older Octura outrigger designs are better overall balanced this way. Current engines are way more powerful than older models originally used in these popular boats back in the day.

Just to know, both, the Octura Wing Ding 60 and the Prather Piranha, are 37in overall length.

 

[Gary Murcott]

Is this the mount I should be looking for I have had 6 or 7 wing dings over the years and yes I did brake a case my tub is 4 inches

 

[David Bryant]

Is this the mount I should be looking for I have had 6 or 7 wing dings over the years and yes I did brake a case my tub is 4 inches

actually that's a nice Octura mount, but may not function properly in a Wing Ding (or Piranha) design, is that 4 inch wide? I've never experienced using a flex type mount in one of these boats. It may work. I would fabricate reinforced bulkheads to increase fuselage structural integrity (using laminated carbon fibre sheet over plywood).

Otherwise you'll want to use an Octura 4-40 or 4-60 solid mount. You can contact Octura.

 

[Gary Murcott]

Thanks David I will call Octura

 

[Gary Murcott]

I called Octura to day and talked to Trudi was able to get the mount what great service

Thanks all for your help

Gary

 

[David Bryant]

I called Octura to day and talked to Trudi was able to get the mount what great service

Thanks all for your help

Gary

Glad everything worked out.

 

[David Bryant]

Circa 1986: Prather Piranha outrigger w/Picco P45 Marine, & exhaust throttle, owned by Jack Oxley. Set 2-lap record on that day.

Was noticing, after re-analyzing this image recently, Jack extended, both, left & right sponson position outward (maybe .625in to 1.00in, could be more) to create wider footprint. Looks like he fabricated aluminum extension plates (.125in thick), which pick-up the sponson bracket mounting holes and the pre-defined (threaded) mounting holes on the sponsons. But after analyzing other images (different Piranha kit's) I'm not sure if he's using the "stock" Piranha sponson brackets (Wing Ding's), they look possibly like the smaller (shorter)versions? Hard to tell from images. Also, the "stock" sponson brackets that were included with the Prather kits were mostly grey anodized.

He also added plywood sheet (.062in) to bottom of left-side sponson riding surface, w/overhang extension (maybe .250in to .375in I'm guessing, toward inside of hull). I'm assuming to provide improved stability in turns/maintain plane easier?