I think that this thread is missing the point of the original question.
The bending strength of the spar is proportional to the width of the section
times the third power of the depth of section.
So 6" x 1" edgeways if 36 times stronger than 1" x 6" ( wing in vertical
dive position).
Half of the aircraft weight at a loading of 5g is crudely equivalent to 3430
lbs loading on the wing (excluding self-weight of wing, contribution to lift
---From the fuselage and tailplane downforce; before you shoot me down on
this!).
3430 divided by 36 is 95 lbs, about the weight of one complete wing.
So supporting the wings on trestles in the dive position will load the spar
to beyond its designed working limit (but not beyond its ultimate limit).
Bolting the two wings together makes no difference, as the maximum bending
would be at the root rib position on the spar, which is outboard of the
section where the two spars overlap.
I don't think that I would be inclined to support the wing as you suggest,
especially as (whilst in the paint shop) someone is bound to walk in and
lean on the tip-end of the wing (or some other miscellaneous additional
loading beyond mere static self-weight).
Duncan McF.
----- Original Message -----
From: "R.C.Harrison" <ptag.dev@ukonline.co.uk>
Subject: RE: Europa-List: Wing supports
<ptag.dev@ukonline.co.uk>
>
> Hi! Pete.
> That's why I said CLAMP THEM TOGETHER but suggest some wood spreaders and
a
> number of clamps.
> You normally carry the wings in the spa horizontal mode when rigging
anyway
> and the spa's are more robust inboard also.
> Regards
> Bob Harrison G-PTAG
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com]On Behalf Of Peter
> Zutrauen
> To: europa-list@matronics.com
> Subject: RE: Europa-List: Wing supports
>
>
> I'm referring to supporting the entire wing with the spar "on it's flat
> side" - 90 deg to the normal operating orientation (as the wing was
> rotated around for painting). At only 1" thick or so, I was wondering if
> there is a problem with concentrated bending moments on the spar at the
> face of the first wing rib.
>
> Still curious,
> Pete
>
> -----Original Message-----
> From: R.C.Harrison [mailto:ptag.dev@ukonline.co.uk]
> To: europa-list@matronics.com
> Subject: RE: Europa-List: Wing supports
>
> <ptag.dev@ukonline.co.uk>
>
> Hi! Pete.
> I would expect they would carry far more weight and stress in flight
> pulling
> 4.8 G be long or short wing, but I'm not the leading authority !
> regards
> Bob Harrison G-PTAG
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com]On Behalf Of Peter
> Zutrauen
> To: europa-list@matronics.com
> Subject: RE: Europa-List: Wing supports
>
>
> <peterz@zutrasoft.com>
>
> Clamping them together sounds like a neat idea - but a question from the
> 'newbie': Can the spars support the weight of the wing with the
> leading-edge down/up without any damage/problems? If it's acceptable to
> do this with the short wings, I assume doing so with the long wings
> would be out of the question?
>
> Cheers & thanks,
> Pete
> A239
>
> -----Original Message-----
> From: R.C.Harrison [mailto:ptag.dev@ukonline.co.uk]
> To: europa-list@matronics.com
> Subject: RE: Europa-List: Wing supports
>
> <ptag.dev@ukonline.co.uk>
>
> Hi! Paul.
> Can't remember what my RAF painter did but HE had room to pin and clamp
> the
> two spa's together, set them on THREE tressles in diving mode!(You need
> THREE to handle the overturning moment of the dihedral. If they are
> nicely
> clear of the floor he can do the leading edge OK then the trailing edge
> from
> above stood on a beer crate or steps. That way you don't need to turn
> them
> OR touch the tips.
> Regards
> Bob Harrison G-PTAG
>
> -----Original Message-----
> From: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com]On Behalf Of Paul
> McAllister
> To: europa-list@matronics.com
> Subject: Europa-List: Wing supports
>
>
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