I was getting a bit sick of the canopy edging strips so I thought I’d start on the engine mount for a change of scenery.
It was a test of my patience, and the jig was a monument to mathematics, but its kind of fun. The welding is still new to me but its amazing what you can do when you practice a little. I’ve even surprised myself a bit.
All jigged up and ready to go. Making a start to the dynafocal ring supports.
01 Jan 2001
Just for those interested, I’ve decided to go with the 160hp engine. Its only taken 5 years to make up my mind but now I’m committed!! One of the major influences in my decision was Luciano Nustrini who considered this engine the best for the Falco. How could I possibly compete with such experience ??!!
09 Jan 2001
Pretty much all done now.. a little more stress relieving to do and then paint it.
18 Jan 2001
One man’s rubbish…. here it is at last.. the noisey bit for the front end.
11 Jan 2002
This one came from Aussie out of a crashed Twin Comanche courtesy of Mark Vinsen at Aviation Salvage in Bankstown. Its had a prop strike and is out of hours so needs a bulk strip & overhaul but the cylinders are quite low time.. all in all a good deal I think.
The engine mount on with all the isolators and spacers. Waiting for the engine to come back from its bulk strip. The Engine turned out to be a real beauty. Just the typical Lycoming camshaft wear and center main issue but otherwise some parts up to new specs.
24th March 2002
Starting to make quite good VP (Visual progress). I picked up my engine from my overhaul man and pulled it over on a crane. After I stopped puffing (1/2 hour later) I put the engine on. Here it is with a start on the baffling.
28th June 2002
Putting the engine back on for (hopefully) the final time. It has now been un-inhibited and run on the test truck with a test club etc. I used the time to powder coat the engine mount.
28th Sep 2003
The first run of the engine on the plane. Great fun !!
22nd October 2003
After advice from someone, I elected to replace the DZUS fasteners with Camlocs. The main advantage is the fact that they are much easier to install and you don’t need all the special tools to set the grommet. Camlocs are much easier to install. The only special tool is Camloc pliers which you can get very cheap or borrow them. If desired, you can also swap the winged fastener for a flush equivalent in about 2 seconds (speed advantage??).The only bit that could ever break is very quickly and easily replaced.. not so for the DZUS. If you want to do the same, the part numbers are:
4002-7W for the winged fastener.
4002-HS for flush mount stainless grommets (more expensive but worth it)
244-16SD for the floating recptacle (Also more expensive but worth it) and 40G26-1 for the retainer ring (Stainless also)
you need a 15/32 drill for the grommet and about 7/16 for the receptacle plus 1/8 (or number 30 more precisely) for the rivets.
Looking around a bit I figured there is a great potential for improvement in the propeller department. I’m not against Hartzell, I just figured that it is quite an old prop and there are a lot of more modern high tech props available now so I had a bit of a hunt around. One thing I will warn about is the fact that the spinner diameter is not that standard so it is hard to find something similar. Also, I was more interested in speed so a 3 blade prop was less desirable. What I do like is the lighter prop from the other manufacturers offering lower polar moments of inertia and less torsional vibration stresses.
For what its worth I approached the following companies.
◦ Hartzell (for a different type of prop) – got no reply
◦ Hoffman – They couldn’t (wouldn’t) do anything
◦ Whirlwind – They were helpful but were still in the testing phase.
◦ Aerocomposites – took a hell of a lot to get them to reply. With that said, I like it. Expensive but I think they know what they are doing and the props look awesome. For now it is a bit out of my price range.
◦ MT Prop – Well the guy was very helpful. It took a while to persuade him into discussing a two blade prop though. In the end I decided against it (although I very nearly bought it) why? 1 – the life is relatively short, 2 – some guys in Aussie had a bad run, 3 – they go back to Germany for maintenance and 4 – the spinner didn’t quite fit. It was a bit small in diameter. (A lot of these problems now fixed)
In the end I ordered the regular Hartzell, mainly because I’m getting sick of messing around and I just want to get flying ! I’ll leave this for another day.
Further to this, Vans has done a lot of testing on various props for speed on an RV-8. The end result had all props within about 3 knots of each other. The best was the scimitar shaped Hartzell. The rest were all very similar with the metal Hartzell of the old shape being better than most. And the MT and Aerocomposites not quite as good. So it seems that it isn’t worth the trouble, especially when you consider the cost of the Aerocomposites prop and the fact that it is experimental without nearly as much experience on the front end of aeroplanes.