I think I realized how sooy glued layers carbon fabric outer loop.

Under 90 degrees to the plane of the rib is formed of equal height shelf template that is embedded in the rib, right?

Hi Valerii,

I'll be uploading a new video in a couple of days showing how I fabricate ribs (the flaperon ribs this time) which should answer your question... I hope!

In the meantime, I hope this drawing will help to illustrate how the ribs are fabricated:



The small flanges (A & B in the bottom drawing) are critical. They ensure that the two layers of carbon remain bonded to each other. If you were to trim the flanges completely off then the two layers of carbon would only be joined together by the foam core (which does not have any structural strength at all.)

Flange 'A' only needs to be about 5mm wide, making your rib 10mm thick overall, and gives you a good bonding surface for gluing the rib to the spar web. You do not have to trim the carbon web from the plane of the rib (to create Flange 'B') - you can, if you like, just leave that carbon web as it is, but this adds a little to the overall weight of the glider... though not much!

Phil.

Hi Phil.

Yes, exactly what I "saw" but only after sent a message №912. The message of №913 I asked if my guess is correct?

You carefully pressed carbon fabric to the template with a wooden spatula kitchen exactly for a snug fit carbon fabric layers to each other and to the template and to create a strict 90-degree angle between the plane of the ribs and flange.

Thank you for your detailed answers, the result will be very detailed instructions and I hope not only for me it helps.

Valerii.

Hi Phil.

Do I understand correctly that the foam in the ribs and other details serves as a frame when forming details and almost does not bear mechanical loads during operation? So I use the lightest foam?

What is the foam, and why you are using?

Val.

HI Val,

That's correct - the foam core is simply there to give the ribs thickness - to hold the two layers of carbon cloth apart and thus creating a stiffer box-beam structure. The foam itself is very weak and does not lend any structural strength to the part.

In the AIR ATOS rigid wing hang glider, the carbon ribs are made in a very similar manner (foam core encapsulated in several layers of carbon. Once the carbon has cured, the manufacturer then dissolves the foam core out by injecting a solvent and flushing out the resulting goo - all to make a small weight saving! I wouldn't recommend doing that with my ribs however - the foam does prevent the two layers of carbon from buckling inwards or being crushed during building.

I use this 75kg/m3 3mm, 5mm and 10mm thick closed cell PVC foam:

www.easycomposites.co.uk/products/core-m...l-PVC-Foam-Core.aspx.

All my ribs and tail boom bulkheads are made from 5mm foam board, with the exception of the main wing #1 ribs, which are 10mm thick. My flaperon rib cores are made from one layer of 3mm and one layer of 5mm foam held together with double sided sticky tape to make up an 8mm thick core.

Phil.

Hi Phil.

When I saw you did rib I was dimmed with tears. So much carbon fabric and epoxy was going to waste, just awful.

Do not get me wrong, I'm not greedy, I just economical, especially at this price on carbon fabric.

I thought that if I use unidirectional carbon fabric that can take half the weight fabric. To the carbon factory that you are using does not work half of the fibers.

Using unidirectional carbon fabric pieces can be neatly cover the carbon fabric rib rack, and then the whole loop around the perimeter with overlapping layers of carbon fabric on the racks. To fix all this thread does not have any waste almost no carbon fabric, a large consumption of epoxy. Another bonus - no need to drill and milled parts, resurfacing only light in the right places before gluing.

How do you like this idea?

Val.