Brolga Props

[Guest kylep]

G'day Everyone,

 

Some interesting news on Brolga props, they are not going to be available soon. The business is going to close up due to illness.

 

So look after your current brolga.

 

Kyle

 

 

[pylon500]

You can fit a Brolga to your Gazelle without CAR 35 approval

Do you have a link to this information?

 

Arthur. (Currently driving an Allsize Gazelle in Taree

 

 

[tangocharlie123]

Dexter the warpdrive distributor here in Aus is W.ade Air in orange still about the same price as a bolly/brolga

 

 

[Guest TOSGcentral]

Latest news TOSG has is that Bolly will be making blades soon after Easter and will then probably move onto hubs afterwards.

 

 

Dexter I am not sure about you comment ‘how it goes together especially pitch blocks’ so here is a general run down.

 

 

• There are three basic types – two blade, three blade and four blade. The hubs are standard generally but equipped to take the blade model.
   
   
  
• They come in pusher and puller configurations so be careful there.
   
   
  
• Diameter is fixed by the blades –Pitch is sorted by the pitch blocks with two each per blade.
   
   
  
• The props are easy to work with and virtually fool proof – you can dismantle or reassemble one in about 10 minutes without the fiddling around that you have with some ground adjustables – the pitch blocks sort that out nicely and instantly without having to get out protractors etc!
   
   
  
• The props come (did come) with excellent assembly and maintenance notes.
   
   
  
• The only real thing to take care with is that the props are individually balanced. So each blade and each half of the hub is stamped with a clear 1,2,3 or four white painted recesses and you simply make sure that each blade and hub half are showing the 1, 2 etc matched markings together at each blade base – too easy!
   
   
  
• It is possible to put the prop on the wrong way around so check your blade profile vis a vis the engine active rotation.
   
   
  

 

 

ASSEMBLY.

 

 

The various components are as follows.

 

 

• Two hub halves
   
   
  
• 6 x bolts and nuts to connect the two hub halves
   
   
  
• However many blades you have.
   
   
  
• 2 x pitch blocks per blade pre drilled for the mounting bolts. The pitch angle is stamped into the block around the narrow end.
   
   
  
• 2 x bolts for each blade and each blade is prior drilled to connect the assembly with no further work.
   
   
  

 

 

Lay one half of the hub on a table. This is going to become the back of the prop.

 

Thread two bolts through it for each blade that you have

 

Load one pitch block for each pair of blade bolts

 

Load a blade for each pair of blade bolts and ensure it is correctly orientated.

 

Load another pitch block for each pair of blade bolts.

 

Put on the second half of the hub.

 

The open ends of the the hub connecting bolts are now facing you – put on lock nuts and tighten lightly so there is still movement in the hub/blade/pitch block assembly

 

Thread through the hub (from the front of the hub) the prop retaining bolts.

 

When these are in position juggle the assembly around a little so it all settles down and aligns

 

Torque up the hub IAW with manufacturer specifications.

 

Offer the complete prop to the drive flange on the engine/gearbox and engage the already loosely fitted prop retaining bolts.

 

 

TORQUING.

 

 

As an overview – what you currently have looks untidy but is practical. The connecting bolts for the prop hub and blades have their lock nuts facing forward. This is to enable you to get a torque wrench onto them.

 

 

The entire prop retaining bolts are going the other way. This looks neater and also enables you to get a torque wrench on them because you work on the heads not the tails.

 

 

The blade/hub assembly is torqued onto the lock nuts.

 

 

The prop retaining bolts are torqued into the drive flange of the engine/gearbox.

 

 

I have personally only worked with 3 blade Brolgas but they all look a similar set up but check the manufactures required torque settings.

 

 

On the three blades the hubs are bolted to 10’/lbs and the flange attachment to 14’/lbs.

 

 

Torque setting should be checked again after the engine has been run and then again at 100 hours plus IAW manufacturer directions.

 

 

LOCKING.

 

 

The hub connector bolts are locked by the nylocks being ‘in safety’ at the correct torque.

 

 

The prop mounting bolts may be either (once at torque settings) wire locked at their heads or nylock used at the other end (NOTE: Do not torque these bolts into the nylocks they must be torqued into the drive flange – just tighten your lock nuts down to a snug fit ‘in safety’.

 

 

PROP PROBLEMS.

 

 

I have not had any. These are very smooth and reliable props. The only fault that I know of (and have seen) is cracking in the pitch blocks. This comes about from poor assembly procedures and ‘forcing the issued’. The pitch blocks are shallow triangles in cross section with a 90 degree return at the thin end to grasp the back of the blade. If the blade has been torqued when not seated correctly then unreasonable force is applied to the neck of the return and this may crack. The blade still cannot come off but it is not ‘healthy’.

 

 

Fortunately this is all in plain view unless you have a spinner fitted. So part of your pre flight inspection with a Brolga is to just check for cracking in this area exactly as you check for cracking in other areas!

 

 

BROLGA PROBABLY FOR SALE.

 

 

I recently picked up a R582 motor for a TOSG member and this came complete with a four blade pusher Brolga. I understand this prop is for sale. It is no good for a Thruster but could be fine for a Drifter. The prop had to be taken to bits to get it into my car so I had a very good look at it and it is in very good shape.

 

 

If anyone is interested then PM me and I will put you in touch with the owner.

 

 

Hope all that diatripe has been of some help to some of you

 

 

Aye

 

 

Tony

 

 

[Guest Andys@coffs]

Hey guys, my old trike had a brolga prop and from dim dark distant memories I seem to recall that the hub was only rated such that a 582 provided the max power of 65hp that the prop was able to safely handle.

 

Is the hub for one that fits a 912 different and rated to 80hp or greater?

 

Or is it simply that I have completely got that wrong and my memory of brolga hp and pink elephants belong in the same rubbish bin....

 

 

[pylon500]

Warpdrive distributor here in Aus is W.ade Air in orange still about the same price as a bolly/brolga

Given the choice, if the same price, I'd choose the Warp prop.

 

The Brolga/Ultraprop hub does need an adapter if going on a 912.

 

Arthur.

 

 

[Guest Maj Millard]

I ran a four blade Brolga on my 582 Drifter for 600+ hours with no problems or worrys. I don't know frankly if I would put one on a 912 however. That's not what they were designed for. I run a three blade Powerfin which is big and strong, and designed for the 912.

 

Remember the propeller is the most stressed component on the whole aeroplane (crankshaft #2) with about eight strong forces trying to destroy it in flight. There is a lot of horsepower in a 912 to be absorbed.

 

The Brolga props are hollow with little white foam blocks inside. The Bolly, Warp drive, Powerfin and most others are solid in construction.

 

 

[pylon500]

The Brolga props are hollow with little white foam blocks inside. The Bolly, Warp drive, Powerfin and most others are solid in construction.

Actually, the Warp Drive is the only prop with solid blades, some of the early Brolga's were solid (glass), but later ones had a foam core.

 

The new Brolga's being made by Bolly are going back to being solid (so I'm told).

 

The irony of this topic is that, if your prop comes into contact with the ground, would you rather shatter a $1600 prop, or wreck a $23000 engine?

 

I know everyone will say you have to bulk strip the engine anyway, but remember, teh 912 has a clutch....

 

Arthur.