I don't think there should be much trial and error if you do the following. Say you want a 3% cambered airfoil. For a 3" chord, that is .09" high. A 45 degree diagonal rib will be 4.24 long. .09/4.24 = .021 = 2.1% camber. Dividing the straigjht rib height by the diagonal rib length will give you the camber percentage. Just plot that Simplex rib along with the straight rib to get everything.
Ray
--- In Indoor_Construction_at_yahoogroups.com, "joemargbartek" <j.bartek@...> wrote:
>
>
> Aki san
>
> Thank you for confirming this.
>
> I have found a calulator on RCGroups from May 2005 which generates a
> Simplex airfoil from Chord and % camber so I can get the 2 or 3
> different templates for a mixed F1L or EZB wing. I opened the *.txt
> file in the post listed below with Excel and was able to get tables of X
> and Y for airfoils. I used the Graphing function of Excel to plot them,
> after adjusting the axes of the graph to give a 1/1 printout. It might
> be better to divide metric chords by 25, or perhaps change the step size
> in the function, to make the calculator more friendly to chords in mm.
> iIt takes a little trial and error to match the height of straight and
> diagonal ribs by adjusting the % camber.
>
> Hope you and others find this useful.
>
> Joe
>
>
>
>
>
> RC Groups, Aircraft - General, Modeling Science, Simplex airfoil
> formula?
>
> Simplex airfoil calculator by JMP_Blackfoot
>
> http://www.rcgroups.com/forums/showpost.php?p=3763107&postcount=15
> <http://www.rcgroups.com/forums/showpost.php?p=3763107&postcount=15>
>
>
> --- In Indoor_Construction_at_yahoogroups.com, "Akihiro Danjo"
> <adanjo-373_at_> wrote:
> >
> > Joe san,
> > Thank you for the correction. I also had realized my mistake but it
> was
> > about 2 hours after my posting.
> > I am getting older.
> > Aki
> >
>
Received on Mon Dec 03 2012 - 06:53:17 CET