The place for technical discussions about GA and flying.
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By a British pilot abroad
#1736713
Hello All,
Recently I have become involved in the maintenance of a Rollason (Druine) Condor so am looking for information.

The joint between the wings and fuselage, aft of the leading edge aluminium fairing, is covered by some plastic trim that is looking very second hand so we want to replace it. What are people using here?

The screws on the canopy are corroded so we want to replace them with stainless ones. They are a random mixture of pan head screws and countersink screws with cup washers. I see in the Rollason parts manual they used pan heads on the fixed parts of the canopy and countersinks with cup washers on the opening hatches. What are people using here?

Thanks for any help, Alan.
By condor17
#1737043
Alan , couple of years ago , a friend who's an expert in fibreglass; made us a pair of wing root fairings ...very nice job .
Not sure how to put 'fotos up . maybe PM me and we can swop emails , where I'll attach foto .
They are about 1/3-1/2 wing chord . Behind them to the trailing edge , one of the group made grey plastic drain pipe [ can now fly in the rain ! ] cut to shape size to nicely curve into the wing/fuselage right angle .
We have a pair of prototype fairings in the stash , as well as the moulds which were used .
All screwed into the structure with stainless self tappers , flat base to the head , slight mushroom shaped Phillip headed .
Canopy , we overhauled last winter. All removed . Where self tappers were loose in tube frame , another member put a spot of weld to shrink the hole . Whole frame sand blasted clean , and powdercoated by local firm .
Where glazing screws went into the fuselage , holes made good by glueing wood dowels in . filled , sanded , then light coat of varnish . Finally refitting frame with new bolts/nuts [ Think we replaced UK bolts with AN- series of similar size ] . Glazing screwed back with the same stainless steel self tappers , flat based head with semi-mushroomed top , Phillips again . The screws holding glass to canopy more stubby than those holding glass to fuselage .
Our weld member then really nicely stopped draughts with various car type 'P' and straight rubber door seals .

Hope this helps , as I said let me have you email and I'll attach 'fotos .

rgds condor .
#1737072
Hello condor17,
It sounds like you have done exactly what I want to do so your photos would be most useful. I have sent you a PM with my email address.
Thanks very much for responding.
Alan.
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By Genghis the Engineer
#1737300
Used to have a share in one, lovely aeroplane, sorry we sold it.

We had ours maintained by Alan Turney at Chiltern Classic Flight at Turweston, I'd suggest dropping him a line and see if he can offer any guidance - he was great with ours and looks after a lot of other vintage aeroplanes.

G
#1738700
Hello GtE,

I can find no current info on Chiltern Classic Flight and believe that they are no longer in existence. I guess I will be corrected immediately now ;-)

Anyway condor17 has sent me several photos of his lovely Condor so I have a way forward.

Thanks, Alan.
#1751556
A little more on the canopy screws.

Some of them are 1/2 in long pan head machine screws. I measure them as 0.1535in diameter with 36 tpi. That makes them a #7 UNF that is a size that does not exist.

Anyone know what they are?
By MikeW
#1751584
a British pilot abroad wrote:A little more on the canopy screws.

Some of them are 1/2 in long pan head machine screws. I measure them as 0.1535in diameter with 36 tpi. That makes them a #7 UNF that is a size that does not exist.

Anyone know what they are?


Isn't that M4 X 0.7, within measurement error?
#1751798
For the thread pitch it certainly is within my measurement error. But I also measured the diameter as 3.9mm that is small for M4 and an M4 nut is very loose on the screw so I had discounted them being metric.

Being designed in France and built in Britain who knows.

I will try an M4 screw in the canopy but I guess the way forward is as done by condor17 above, shrink the hole with weld and use #7 self tapping screws.
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By a British pilot abroad
#1752472
I believe 3 BA is bigger again at 0.1610in (4.1mm) so I don't think so. But the difference in thread pitch & angle is well within my measurement error.
By Aerials
#1753057
A suggestion for you; place a screw from the canopy parallel and touching a new M4 or other known screw so that the threads intermesh. Hold the assembly up to the light and you should see if they match quite easily. If they are close in pitch but not a match, there's no way they'll intermesh along the length. There may be light showing at the crests and troughs though because of how the screw threads are profiled but as long as they intermesh, you'll have a match.