Justin's Raven

[justin.schoeman]

8mm hole in the skin

DSCF1306_opt.jpg

Excellent. Simplicity is always the best. Simple, robust and aerodynamically clean. I may just end up borrowing that idea!

Thanks!
-justin

[justin.schoeman]

How about a pic of the part you made, please.

Only have post-installation pics.

Here is the original end rib:

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Just a flanged rectangular plate that only covers half the surface.

Here is my attempt:

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Far from perfect, but it should do the job. Yes, it is a little skew - I had to take a template of the current LE, as it was bent off centre, and I could find no sane way to straighten it. Shouldn't have any real impact though.

I will use some 2 pack body putty to close it up and smooth it off. Will do the same for all the other end ribs to have aerodynamically clean ends everywhere.

[justin.schoeman]

Didn't feel like making more fillets today, so I worked on a mock up for a throttle linkage. I don't have any welding equipment yet, and I want everything adjustable anyway, so I tried to do an assembled, rather than welded system.

Here is a mock up of a torque tube with one arm attached. The tube is a 13mm aluminium extrusion from Builder's Warehouse, and the arm is 25mmx2mm bar extrusion from the same. The washers are a tad large, but all that I could find in my 'nuts and bolts' box...

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Holding the arm 10cm from the tube, I was not able to move it. At 30cm from the tube I could get it to slip a little. So it may not be sufficient.

But it may well work. I only require a 10cm arm - so it seems unlikely that even a strong pilot will be able to exert sufficient force on the throttle controls to damage the linkage.

Advantages:
- dead simple to build
- fully adjustable

Disadvantages:
- not well tested
- it may well be possible to twist the arm on the torque tube
- how will vibration affect it
- requires a lot of clearance around the torque tube for the clamp end of the arm

In the end, I should probably go for a welded steel construction like Zenith recommends, although it is very tempting to use this configuration instead...

[Boet]

Do as the plans say please. WELD the damn thing. Stop buggering around.

[justin.schoeman]

Do as the plans say please. WELD the damn thing. Stop buggering around.

Yup. Good advice. It's nice to have something adjustable, until it adjusts itself in flight!

I will use the aluminium mock-up to get the throws right for the stomberg, then have one made up in 4130. Simple, and indestructible.

[Boet]

TX for listening to sound advice. Herewith pics of how I have done the throttle system in the BB`s. The cables allways gets pulled in a straight line. IE, no wear on the cables. The little 'drum" is made up out of a piece of thinwall exhaust tubing. Hope you can understand what is going on here!

[justin.schoeman]

That setup looks great. Unfortunately, the Raven has no space for something like that - the fuel tank sits very close behind the panel. What is the approximate diameter of the tube. Maybe I can fit it in other side the firewall?

[Boet]

I use a 4" pipe. Can work in front as well. This system works very smooth.

[justin.schoeman]

I use a 4" pipe...

!!! I would hate to see (hear) the exhaust that pipe was made for!

10cm doesn't fit in anywhere. I will have to use the stock zodiac design .

[justin.schoeman]

Just made the mistake of sitting in the plane. I was planning on just figuring out how to do the centre console, but sat there for an hour, thinking about side panels, moving the brake handle, etc. Basically just sitting there imagining it flying, and making 'vroooooom' noises...

I think I must take next weekend off, and dip into the reserve funds for a bit of H&F, before the withdrawal symptoms get too bad!

Did finish off the rudder, and rudder fairing though. Need to go back to the workshop now, and actually make the template for the centre console, instead of just dreaming about it!

[grostek]

Just made the mistake of sitting in the plane. I was planning on just figuring out how to do the centre console, but sat there for an hour, thinking about side panels, moving the brake handle, etc. Basically just sitting there imagining it flying, and making 'vroooooom' noises...

I think I must take next weekend off, and dip into the reserve funds for a bit of H&F, before the withdrawal symptoms get too bad!

Did finish off the rudder, and rudder fairing though. Need to go back to the workshop now, and actually make the template for the centre console, instead of just dreaming about it!

Hi Justin,

Dreams are needed to improve the reality .

Kind regards,

Gunter Rostek

[justin.schoeman]

Well, a solid afternoon's work, and the centre console, and mounting brackets are done:

Run out of rivets, so I can't install it yet. Tomorrow I make mounting brackets for the transponder and radio.

Now I need to decide what to do with the brake. It was mounted directly in front of the stick, but the console goes there now. I was thinking of putting a T handle twist lock cable towards the bottom of the centre console, and using some pulleys to boost the pull a little.

Any other ideas?

[Wallaby]

Aah, I see that you made the same centre console as the guys that builds the CH 601's on their website. I've always liked the centre console. Seems to fit the plane better. Are you going to have a single stick or the Y-stick? Because if you stay with the single stick, why not put the hydrolic brakes as the Bantam and some of the Challengers have, on there? Then you have the brake handle on the stick and it works better than the drum brakes. What are you going to put on that centre console? Damn, I like that centre console......I think a Bush Baby will also look nice with one

[justin.schoeman]

Yep. I saw a picture of one on the ch601.org site. No plans, so I just measured up the gap, and the transponder, and made it all to fit. The straight section at the top is sized for the transponder, and the radio will go underneath it.

Both the radio and transponder are too long to fit in the standard panel - which is why I had to make the centre console.

The brakes are mechanical. I don't think I could squeeze a hand lever hard enough. I have been looking at fitting hydraulic brakes, but I can't find a system that works with drums, so I would have to replace wheels as well. And that would blow the budget (further).

[Wallaby]

Yes, THE BUDGET...... Funny how the budget seems to drain faster than you would imagine.
The hydraulic brakes, I think is about R6800 with the new wheels and rims. With the hydraulic brakes you can exert a much bigger force on the motorbike style handle than on the same type application drum brakes. I think that's why the Raven has a longer brake handle so that you can exert more force with the longer arm of the handle.

Oh yeah, and the only way that a budget will ever work is; When you budget, you take that amount and you double it and then you put 20% with the new budget.....That's the budget you are going to use. A budget is always a stick in the spokes.
Maybe you must use "the budget" as brakes

How's the engine coming along?