Scale Soaring UK

Evening all!

Many thanks to Chris Jesshope - I am now the proud owner of his Rhonbussard. He had radio problems which led to a hard arrival, but the damage isn't too bad (pictures below). I will post pictures here as I work through the repairs, and welcome any comments or advice which you may feel like offering.

Here is the nose damage : Chris has started to repair this with carbon. I check the alignment, and then rebuild the internal former and stringers before replacing the sheeting. This repair looks straight forward.

Wing damage: About 8" of the spruce trailing edge is missing , and the rear spar has a kink in it. Straight forward repairs with a bit of balsa (and spruce) bashing!

Wing mount damage: The wing seat is not parallel to the tail, and it looks like the current position is wrong (looking at the gap in the former above). I suspect it took the brunt of the arrival. I will remove the wing seat again, and make some doublers for the formers (not full former, just around the breaks and feathered in) before remounting everything in line with the tail plane. Then I can re-sheet the fuselage and replace the covering. I will have a look around at options for the colour scheme.

In terms of other tasks - the pilot is pretty tired, and I may have to replace him, or at least find a way to freshen him up. I think I will put a multi plug under the wing seat to take the harnesses from the wings This should simplify the assembly process. Currently the servo leads are bundled together, and routed around the pilot to plug in under the dash. At the moment I don't need to give this much thought. If anyone has any ideas about the source of the plans (or kit, but I suspect it is scratch built from plans) I would appreciate knowing. The wing span is around 130" (ish), and it looks like the fuselage is constructed on half formers with the second side built onto the first.I am not the quickest builder (too many other things getting in the way), but I will record everything here. I will be asking for some advice when I get to covering and painting!

Paul, I have a few more of this if you're brave enough (it is only a few):

That looks nice - I would love to see the rest!

It does look like a serious painting challenge

Here you go:


This has been modelled before - quite a few years ago now and I managed to have the 'Rhonbussard' logo cut from vinyl by a sign supplier for the builder of the model so it should be more than possible to have it done these days.

I also have some photos of Chris Wills' Rhonbussard but it is rather dull (but easy):


All the photos are scans from hard copies so are not brilliant quality.

Thanks for sharing. Actually, the red and white one doesn't look too bad, if I can get the name produced in vinyl (once in red and once in white). The red over white with the black dividing line should be doable, and the wings look straight forward with just the red tips.

My plan is to get is back in one piece first - I can give the colour scheme more attention at that point!

That's how it was done - one set of white (ivory I seem to remember), one set of red. The Gothic script came straight out of the printer's library, not an exact match for the full size but near enough.

Good luck.

No pictures, but I have stripped all the covering off the fuselage, and removed the wing seat completely. I noticed the tailplane is not perpendicular to the fin and rudder, and it seems this is because of the soft balsa seat it is mounted on. The rear underside of the tailplane has two strips of wood about 8mm wide added, perhaps to adjust the incidence? Anyway, these had compressed the balsa on the tailplane mount. I will replace about 10mm of the tailplane mount balsa with some 1/16 ply - this should be more resistant to deformation without adding much weight to the tail area. Once I have a good mount for the tail, I can re-attach the wing seat portion and ensure the correct alignment.
I'll take some pictures next time I am working on it!

Okay, some progress, and if my phone decides to play ball and upload my pictures before I finish typing, possibly a picture or two.
Progress so far:

• 1/8th ply plate fitted at the back of the tail plane seat. This is the point the incidence wedges were digging in, and causing the tail plane to be misaligned with the fin. This resolves the alignment issue.

  

  Tail seat modification

• Wing seat re-attached. Alignment is now good between the fin, tail plane and wing, so I will be making some doublers to strengthen the butt joints formed when re-attaching. The goal is not to over strengthen the area, but to return it to the designed level of strength.

  

  Wing seat re-attached.

• I have stripped both wings. With the condition of the paint, I decided it is better to start again. I also want to have a closer look at the air brake servo mounts, as the operating range and throw are quite different from one side to the other. The servos are buried in the wing, so this will involve removing some of the d-box sheeting
• I have also stripped off the tail plane, again due to the paint condition.

So now I have a list of questions!

• Is there an easy way to remove pin hinges which have been epoxied in? I am wondering whether I have to cut them in half and work on each side separately. Pin hinges have been used on the tail plane, and I am worried about damaging the structure if I put too much force on them. The flat aileron hinges had been pinned, and I managed to pull the pins out with a minimum level of damage.
• What do you recommend for covering the wings? In the past I would have assumed Solartex to be the best option, but as I understand this isn't available any more. I want to be able to paint what ever I end up using. I quite like the vintage fabric look - if that's possible...
• Should I consider glassing the fuselage? It is balsa skinned, and I guess this would provide some additional protection. The fuselage will be painted all over, so you wouldn't see the glass cloth.

Apologies about the "grass" - we are currently in the process of re-landscaping the garden...!
Thanks for reading, and thanks for your advice!

Paul,
Looks like good progress so far
As far as the pin hinges are concerned, I would probably opt for cutting the pin hinges in half & then try to drill out the plastic barbs starting with a very small drill in a pin vice & then work up slowly till the remaining thin shell can probably be extracted.
I would certainly go for glassing the balsa fuselage skin. I did this on my 0.4mm ply skinned Oly & it toughened up the structure considerably. It also gave a good paint surface as shown below.

Not sure about modern equivalent to Solartex, but I’m sure someone like Chris W will know.
Peter

Unless the position of the hinges is critical, could you cut off the old hinges and install the new ones alongside them?

One way of dealing with hinge removal (Robart pin type) is to use a sharpened brass tube slightly larger the than the diameter of the pin, attach it to a drill and do the biz...The resultant hole is neat and only slightly larger than the original, allowing for epoxy to make up the difference.

As to a Solartex equivalent, I still have some precious stock, so haven't had to find a substitute. (Smug mode) If the Rhonbussard is 1/4 scale, I would recommend using film for the flying surfaces, as this will make for a significant reduction in the AUW.

Thanks for the ideas about getting the pin hinges out - I will give them a go.

I will glass the fuselage - yours looks good Peter!

If I use film for the wings Chris, I guess I can't paint it?

Paul,
There was a response from Frank Skilbeck about alternatives to Solartex in another recent thread:
“Diatex or Diacov, Diatex is what they use to cover microlights, but needs an adhesive, Diacov is Diatex with an adhesive backing. Only comes in natural so you have to paint it.

You can buy Diacov from Sarik by the meter.”

Hope this helps.
Peter

Thanks Peter - I'll go and look it up!

Edit - Diacov 1000 ordered from Sarik, along with a proper iron (it's about time - I have been using the household iron for the last 40 years)!!

Finally got back to this, having been diverted to several other things (non modelling).

The wing is now repaired. I spliced new spruce into the sub spar top and bottom, and replaced the broken section of trailing edge. With new ribs and gussets, I am quite happy with the result:

I cut away the sheeting over the airbrake servo as I am concerned it is jamming. I will spend some time exploring if/why this is the case before deciding whether to do something about it such as replacing the servo / linkage.

The fuselage now has fewer holes. I have sheeted the nose section, and a couple of the holes in the tail fin.

I need to sheet the area around the wing seat, but I am considering if the current repair on the formers is good enough, or whether I need to add some thin doublers over the original breaks. Currently I have carbon tows on one side of the formers over the breaks. This area let go when it crashed last time, leading to the wing damage. I don't want to beef it up (I know where that path leads...!), but to return it to something close to its designed strength.

I am planning to use a light filler to smooth off the surface on most of the fuselage (lots of small dents and marks to cover up), taking care to avoid increasing the weight. I will then glass and paint it.

Peter Balcombe wrote: ↑28 Feb 2021, 13:39 I would certainly go for glassing the balsa fuselage skin. I did this on my 0.4mm ply skinned Oly & it toughened up the structure considerably. It also gave a good paint surface as shown below.

Good afternoon Peter - What weight of cloth do you recommend for the fuselage skinning? I am getting close to this stage, and want to buy it in ready!

Thanks!

Paul,
I used normal lightweight wing skinning type cloth (25gsm) so it doesn’t add much weight.

Thanks Peter - I’ll get some ready!