Super Diamond Engine Mount Build Thread

[old man emu]

My boss has been asked to help a homebuilder make the engine mount for a Super Diamond. The engine is a Jabiru 4 cylinder.So far a jig has been made to assist in the locating of the frame work.

 

As soon as possible, I'll post some photographs of the jig. When the day comes to construct the mount, I'll photograph the process and post a build log.

 

At the moment I'm having trouble posting pix on this forum. If anyone urgently wants a look at the jig, just PM me with your email address and I'll send them through my work email address.

 

Old Man Emu

 

 

[old man emu]

The first step in making the engine mount was to make a jig so that the spatial arrangment of the components was set before any cutting and fitting was done.

 

The jig consisted of a base board which represented the firewall of the aircraft. Short lengths of tubing were inserted into the back board to replicate the fuselage longerons. Note how the lower pieces of tubing emerge at an angle from the firewall.

 

Engine mounts were fitted to another piece of board, and threaded rod was used to set the distance between the firewall and the engine mount board. Use of threaded road allowed the engine mount locations to be varied to allow for displacement of the engine's thrust line to the left or right, and up and down.

 

In this instance, the nose wheel attachment bracket was attached to the firewall board so that struts could be fitted between the bracket and the engine mount.

 

After all distances and angles were checked for accuracy, construction of the engine mount began.

 

Short pieces of tubing, all of equal length, were cut and fitted into the longeron positions. Then further lengths of tubing were fitted to reach from the longeron tubing to their adjacent engine mounts. The ends of these lengths were 'bird mouthed' to enable them to be welded to the short longeron inserts and the engine mounts.

 

As of 5th May 2008, that's how far the build has progressed.

 

Old Man Emu

 

 

 

 

 

 

[coltri]

Old man emu,

 

I am building a Cheetah (Brisbane-southside) & my bottom longerons are narrower than the top longerons, why are your firewall longeron penetrations rectangular?

 

Coltri

 

 

[pylon500]

That would be because the 'SUPER DIAMOND' is a single seater and has a square fuselage section.

 

Was originally powered by a 503.

 

Arthur.

 

 

[old man emu]

Sorry that I haven't been keeping this up to date.

 

The engine mount has been completed and is fitted to the aircraft. I'll have to nip up to the builder's place to get some photos to post.

 

Coltri,

 

The enging mount jig shown here is specific to the plane being built. As Pylon500 says, the aircraft being built has a square fuselage section. If you are going to make a jig, make it with the spacings that suit your aircraft. What I was trying to do here was to describe a method of making sure engine mounts fit the airframe they are going onto. Each specific case needs some modification of the actual build to suit the airframe it is being built for.

 

Old Man Emu

 

 

[coltri]

Thanks Old Man Emu, I have since re-read your first post & there in bold is "Super Diamond".

 

Coltri