6.3.3 - Fabrics

Question 1

List the threads used in a fabric in all direction?

Question 2

What is a roll of fabric called?

Question 3

What would red thread indicate on a selvedge?

Answer 3

Major weaving defects are marked on the selvedge with red thread.

Question 4

In what conditions should fabrics be stored in?

Answer 4

Fabric should be stored on wooden racks at an even temperature of about 20 ^C and a relative humidity of 70%

It should be kept dry, protected from
sunlight, and should remain in the original paper wrapping. It must be kept
away from oils, greases, dope, spirits, and acids.

Question 5

Which fabric is used for high strength application?

Answer 5

Unbleached Irish Linen is used where Strength is the most important factor.

Question 6

Egyptian cotton is normally used to make what for aircraft?

Answer 6

Egyptian tape/cotten tape is used for covering ribs, booms etc before stringing.

THis tape is selvedge

Question 7

Where is nylon cord used on a fabric aircraft? Name another type?

Question 8

Describe the thread that is used to hand sew fabric with?

Answer 8

Waxed threads are used for hand sewing, but waxed and un-waxed types are covered by the same specifications from suppliers

Question 9

Name two type of aircraft stitching and what might be applied over it afterwards?

Answer 9

herringbone Stitch and boot stitch

Applied over it (doping)??

Cover the stitches with an overlap of Egyptian and a serrated tape

Question 10

What type of products are man-made fabrics?

Answer 10

The two main types being used on aircraft are:

Polyester and glass fibre

Question 11

How do you apply tautness to a fabric that is being installed?

Answer 11

Doping

Question 12

What is the term used to fill in a hole that is 2” or less?

Answer 12

Small holes not exceeding 2’’ diameter may be repaired by darning

Question 13

What type of needle is used? (For darning)

Answer 13

A curved needle is used

Question 14

What type of stitch is used on the trailing edge?

Answer 14

The trailing edge is normally sewn with an over hand and lock stitch

Question 15

Describe the normal method for cutting an opening in a fabric?

Answer 15

Fabric covers often require opening up for repair or inspections of internal members.

Cutting of the fabric must be kept to a minimum.

The normal method is to make an ‘L’ or an ‘X’ shaped cut, parallel to warp and weft.

On completion of the work, the fabric must be repaired as with a tear

Question 16

Dope fabric must have a special edge to it, what is it called and how does it look?

Question 17

Why do you dope a fabric on an aircraft?

Answer 17

To produce and maintain the tautness in the fabric

To make it both air and moisture proof

To produce an aerodynamic smooth surface

To protect against the deteriorating effect of sunlight and heat

Question 18

What is blushing effect?

Answer 18

When doping a fabric, if temperature or humidity is outside the ideal limits, it may result in ‘blushing’,

Shown by the finished surface being dull or white, and it indicates that the dope applied has lost most of it’s desirable properties

Question 19

What is orange peel effect?

Answer 19

If you have a painted surface, orange color can show where there is bad conditions prior to a paint job.

Question 20

What direction must you wipe the dope in when applying?

Answer 20

The first coat must be rubbed down with a fabric pad, in one direction only, leading edge to trailing edge.