Precedent T180 Restoration

I use Eneloop batteries in my transmitters. They're great. I'll come back to the power setup later, I don't want to get too far ahead of myself.

Anyway... I started tidying up the fuselage. The window plastic had been epoxied on, so was a royal pain in the a*** to get off. I had to skim over with light filler and sand it.

I also planed off the epoxy from the tail. I think I'll probably replace the wedge of Ply when I rebuild the tail, as I want to create a slot for the tail, down into the fuselage for more support.

I also think I'll either build up, or build a new servo tray. There's not currently a place to fix the receiver to.

(before and after)

If you can - add a hardwood load-spreader above that block with the blind nuts, where the trailing edge bolts go - to make sure it cannot pull out under any G loading. Then check you have some washers or similar under the bolt-heads but above the te, so the heads can't pull through!

Thanks, I'll look into that. I need to double check the wing alignment. I test fitted it earlier, and there was some gaps at the leading and trailing edge. So I'm not convinced it's square. Before I finish it all, I'll check the measurements to make sure. But I might need to redo the t nut positions if it's not square.

Paul
The Eneloop chemistry is 1.2V but 6.1 v would not be a surprise when under charge.

Did a bit more work today to fix the nose.



It was like this...

While I was looking at the nose, I started thinking about the engine mount.

The plane came with the mount at 45 degrees.


So I was wanting to mount my engine either at the same angle, or 90, so the exhaust goes underneath. There's a channel that seems to be for it.

But that would make it tricky to get the throttle cable to the carb.

It's not a great photo, but you can see it's quite low down. So I'll need to work out what to do. I'm hoping to not have to redo the firewall, as that'll be a lot of work.

On to the serious stuff.



I'm still in 2 minds whether to try and rebuild the tail from scratch, or just repair the existing one. All that needs replaced is 2 ribs, and the sheeting on the underside where it joins the fuselage. I could just beef up the area to strengthen it.

One aspect to consider is that weight in the tail is far more significant than the same weight added to the wing or nose.
Almost any repair tend to add weight to achieve the same strength as the original. Even a few grams at the tail needs several times that in the nose to compensate. If your motor is lighter than used in the original extra tail weight will only add to any ballast required.
A new build tail plane should match the original's strength and weight.

It all comes down to a judgement decision.

I agree with Simon about weight.....build a new one !

Easier said than done though. I've never built balsa before. These plans were assembly plans, for the provided pre-cut parts. So I'd now need to make all the ribs and spars myself.

It would be a satisfying achievement if I managed it, but feels like a long shot at the moment.

Throttle push-rod - use a bike spoke - easily bent by hand, but stiff enough to retain it's shape, so you can bend it into all kinds of weird shapes to get the drive where you want it!
And the other end is ready threaded just right for a clevis!

Back from holidays, and there was a delivery of control horns and connectors waiting on me. Always nice to come home to swag :lol:

I picked up a new, but second hand scroll saw for £40. It's never been use so seemed a bargain.

I'm now thinking about how to cut out the ribs for the tailplane.

My plan is to trace the outline of the rib from the plan, then make a template of it from poster card. Then use that to mark out the ribs on balsa and cut them out.

Anything wrong with that plan? I've never scratch built from balsa before.

I am not sure you need a scroll saw to cut out balsa whereas for plywood yes.
If I were doing it I would actually use the scroll saw to cut a ply template. When you are happy with the profile, for a power plane tail a constant smooth shape is more important that the exact profile, I would then use that as the master and actually cut round it over the balsa with a suitable scalpel blade.
With a bit of practise you should find the ribs end up almost exactly identical and need only the lightest of sanding.
If the ribs have spar 'notches' in them cut them out, or wood file them out, after the rib has been cut out.

Quorneng wrote: I am not sure you need a scroll saw to cut out balsa whereas for plywood yes.

Well maybe I didn't "need" one, but I fancied getting one for a while, and I'm sure it'll be useful for future builds.

Quorneng wrote: If I were doing it I would actually use the scroll saw to cut a ply template. When you are happy with the profile, for a power plane tail a constant smooth shape is more important that the exact profile, I would then use that as the master and actually cut round it over the balsa with a suitable scalpel blade.
With a bit of practise you should find the ribs end up almost exactly identical and need only the lightest of sanding.
If the ribs have spar 'notches' in them cut them out, or wood file them out, after the rib has been cut out.

Thanks for the tips. I thought about just using a scalpal, but thought it would be more consistent with the saw. But I can see how the Ply template would work with the scalpal.

I always make a ply template, I soak the edges in cyno to toughen them up.
As you've now got a saw you could make 2 templates and use the sandwich method to produce your ribs, clamp strips of balsa between the templates and cut and file to shape...one set of identical ribs!!