Front Wing design and build1

[GrantL]

5-6mm chopped matt mold with structural stiffness to stop mold twisting

Mold removed from split plate. Flanges light wet sand with 800. Wing cavity as laminated. Ready for waxing for 2nd half

[mcfly777]

Thank you this is really helpful. Look forward to additional steps!

thanks
Leo

[GrantL]

Waxed and ready for 2nd side

Pinot helps with waxing application

[BWD]

Interesting, would have thought Grenache or Syrah to be more typical foil wines. But you might be onto something...

[GrantL]

SECOND SIDE HAND LAYUP.
Laminate outside or with good ventilation. Outside is best with sun. This allows the resin to set off evenly with heat from sun.

Carefully gel coat all over

Split chopped matt laminate in half. Cut pieces to butt up to plug all around

Carefully wet out laminate to edge for plug

Prepare another thin layer to cover the plug

Place prepared piece of laminate to go over plug. Wet out completely with roller removing any air bubbles.

Allow 12hrs to dry.

[GrantL]

Add multiple layers of laminate to build up thickness. Reinforce lastly same as 1st half

Wedge open 2 halves with plastic or hardwood wedges to release 2nd half. Remove plug front mold.

2 mold halves, plug removed. Ready for clean and polish of cavity and flanges.

[revhed]

Xcelent info thanks!
Would you, could you please explain in detail just how you get your split plate perfectly aligned with plug center PLEASE!
I have been semi happy with the few molds I have made but always find L E and more importantly T E to not be as clean as I would like.
As you have so kindly done above, photos and your technique would sure be great as I am just now wanting another F wing and R wing soon as winter project.
R H

[GrantL]

Xcelent info thanks!
Would you, could you please explain in detail just how you get your split plate perfectly aligned with plug center PLEASE!
I have been semi happy with the few molds I have made but always find L E and more importantly T E to not be as clean as I would like.
As you have so kindly done above, photos and your technique would sure be great as I am just now wanting another F wing and R wing soon as winter project.
R H

.

Exactly it is not easy by hand , but the method I use seems to be pretty accurate.
The most important step is in the manufacture of the plug. When I make my plug I make a frame with multiple ribs (profiles) spaced every 20mm or so , a little less on the tips. This is the only way to accurately make a plug (wing) with symmetry left and right. Anhedral , dihedral and accurate washout is possible also. I suspend the wing profiles on a frame which I can measure with a vernier height gauge to position correctly and angle relative (AOA)to the middle centerline profile (AOA=0). When I haveall the ribs in place I cast between each rib. It normally takes about 3-4 casts to fill up everything. I have tried bog but casting is quicker. I make my ribs out of steel , laser cut but you could cut and file from aluminum. The reason I use steel is that I can now file or sand (wet of course) the casting resin back to the ribs with out loosing the accuracy of the leading and trailing edge profile. You tend to get slight flats from rib to rib across the length of the wing but this is easy solved later.

end view showing steel rib with holes for bonding

my used frame with plug sitting on top to give you an idea

I then hand laminate150g on twill on top/botom to give the plug some strength.I allow 0.2mm per side for the laminate and some finishing primer. This is about the most accurate way I can think of to make a complicated wing profile unless you want to machine from solid on a CNC machine. But that defeated the purpose of hand making a wing.
The reason the frame/jig is so important is because you now have a matrix of accurate dimensions to make the split plate (pic on page 2 ). Any errors in the split plate will only be +/- 1mm out. This can easily be rectified by sanding the MDF or adding a little finishing bog . I put a very thin black line all around the wing which makes it easy to align plug and split plate.
Hope this gives you some idea of my method.

Grant

[revhed]

Thanx for your quick reply.
I want to reproduce a wing that I already made by painstakenly shaping the bottom as my male mold has a flat cord top.
I do almost exactly inverse as your plug build by using external thin plastic profile templates to shape layed up parts, to much work!
I am quite sure that I have used up WAY to much time and elbow grease doing this both on several wings and STRUTS.
SO, as I do not have your plug matrix as you so kindly described above, how you you proceed making a mold with a F wing that has already been flown all summer and is well liked what is what you call "bog" did a quick search and found nothing?
Thanks, R H

[GrantL]

Thanx for your quick reply.
I want to reproduce a wing that I already made by painstakenly shaping the bottom as my male mold has a flat cord top.
I do almost exactly inverse as your plug build by using external thin plastic profile templates to shape layed up parts, to much work!
I am quite sure that I have used up WAY to much time and elbow grease doing this both on several wings and STRUTS.
SO, as I do not have your plug matrix as you so kindly described above, how you you proceed making a mold with a F wing that has already been flown all summer and is well liked what is what you call "bog" did a quick search and found nothing?
Thanks, R H

Sorry for the confusion, but the colloquial term "bog" is automotive body filler. I understand you have a wing (French) "F wing" you want to copy.?