Intersection fairing layup issues

[Cam7nut]

Hi,
I'm making my wheelpant to gear leg fairings and have been having trouble getting the fibreglass cloth layups to conform around the sharp radius of the trailing edge and aft part of the fairing.
I tried a dry run with 1 piece of cloth for the front and one for the rear. The front conformed ok but the rear, once wetted would not follow the tight radius.
Any suggestions?
I'm thinking maybe an inch width strip along the sharp radius and cut the main part of the layup to conform to the profile of the curve.
Any suggestions from builders who have successfully made their fairings would be much appreciated.
Cheers,
Cam

[woodmanrog]

Be sure to cut your fiberglas at a 45 degree angle (on the bias,). It will then form around the curves easily. You can lay up in several pieces as well. Be sure to use a stiff separator such as a thin piece of aluminum, at the aft end so you can remove the fairing easily after it hardens. Good luck.

[BobRv4]

Try laying the glass at a 45 degree bias to the edge, this will help it lay down better. Or you can make it a split line to help removal. Lay a thin piece of aluminim along the edge lay over it, once cured remove the aluminim. Make sure you wax or add release to it. You can also glass this split line from the inside built up with glass or flox, then it's just and easy bondo and fill job.
It's a sharp edge so maybe a pain.

[BobRv4]

Just like he said!

[Cam7nut]

Thanks.
I was intending to make the fairing in one piece and then Dremel cut it along the wheel pant split line.
I'd like to permanently attach the fairing halves to their respective wheel pant halves.

[DanH]

Placing the weave at a 45 to the edge won't help much with an edge that sharp.

I'd try a flox corner.

[sblack]

Yep, no way it will turn that corner. I would cut the corner back about 1/8", lay your first piece down and trim it 1/2" past the trailing edge. The lay in some flox to back fill the void, the lay up the other side. It will be a 1 pc fairing.

[Cam7nut]

Thanks Dan and Scott.
I decided to do as you say and use a flox trailing edge.
Also thought it might be easier to lay the top half then trim the trailing edge once the epoxy starts to harden. The top trailing edge will need to be pretty much flush as the lower layup will tend to push away because of the intersecting angle.
I cut a pattern for my 2 layers and also added an inch wide strip along the trailing edge, also overhanging a bit.
I'll fibreglass the bottom tomorrow.

[Cam7nut]

Progress pics,

[DanH]

Pretty work Cam.

Classic flox corner procedure below, illustration from Rutan's "Moldless Composite...."

Looks like you've elected to install the flox after laying up both sides, which is fine. That's the nice thing about FRP; understand the fundamentals, and you can use whatever procedure fits the situation.



Suggestion; After bonding the fairing to the wheel pant, cut away the unused wheel pant skin inside the fairing, clean out the form material, sand well, and lay another two or three plies overlapping the inside of the pant skin. It will ensure that the bonded-on fairing doesn't delaminate from the pant, given lots of grass field abuse.