Backpack Construction
Construction FAQ's
C1 What materials are utilised in manufacturing White
Mountain™ Backpacks?
- 950 Denier Kodra - Polyurethane Coated.
- 420 Denier Rip Stop Nylon - Polyurethane Coated.
- 420 Denier Nylon - Polyurethane Coated.
- 600 Denier Polyester - Polyurethane Coated.
C2 What is Bar Tack Stitching?
Bar Tack Stitching is multiple of straight stitching that crosses a piece
of cloth at a right angles. This provides added strength to that area of
stitching.
C3 Do White Mountain™ Backpacks have Bar Tack Stitching?
All areas subject to stress have Bar-Tack stitching.
C4 What Thread is used on White Mountain™ Backpacks?
Nylon thread is utilised in all stitching of White Mountain™ backpacks
providing durability, strength and rot resistance.
C5 What stitching process is used on White Mountain™
backpacks?
All White Mountain™ backpacks are twin stitched at eight stitches per
inch.
C6 What zips are used on White Mountain™ Backpacks?
YBS Coil Zips are used throughout the entire range of White Mountain™
Backpacks.
C7 What Buckles and Clips are utilised in White Mountain™
backpacks?
All Buckles, D-Rings and Clips utilised in the construction of White
Mountain™ backpacks are National Moulding Duraflex and virtually unbreakable,
non-slip and easy to adjust.
C8 What Webbing is used on White Mountain™ Backpacks?
All webbing utilised in the construction of White Mountain™ backpacks is
of the highest grade Nylon or Polypropylene and heat cut to prevent separation
at the ends.
C9 How is the Backpack Length determined?
In designing backpacks for White Mountain™, measuring numerous body types
and studying backpacks manufactured for other wholesalers internationally,
we are able to establish some standard dimensions for internal frame backpacks.
One notable standard is the length of the base or bottom section of the
Stave. This is measured from the tailbone between the Coccyx and Sacrum,
to the top of the hip belt at the point where the hip belt crosses level
with the hipbone or Iliac Crest. This length on the majority of people measured
is between 11cm (4 3/8") to 14cm (5 1/2"), with the standard hip belt position
set at the average length of 12.5cm (5 0/0"). The point at which the hip
belt meets the top of the lumbar pad on the backpack can be as much as 20cm
from the base of the stave. But the point at which the hip belt crosses
the hipbone or Iliac Crest is 12.5cm or 5 0/0" from the base of the stave.
The overall length of the parallel staves after subtracting the lower back
length of each stave and the approximate 3cm reduction that is lost in bending
the staves to the curve of the back, is then the Optimum Torso Length. Most
manufactures in the world today use 5 standard stave lengths, 50cm, 55cm,
60cm, 65cm and 70cm. These standard stave lengths can vary by as much as
2cm and would equate to an average Optimum Torso Length of approximately
38cm (50cm stave), 42cm (55cm stave), 46cm (60cm stave), 50cm (65cm stave),
and 54cm (70cm stave). White Mountain™ use only 4 stave lengths to a maximum
stave length of 65cm.
Please look to our page on
Torso Length FAQ's for further details.
C10 How is the Backpack Width and Shape determined?
For total stability the backpack should be symmetrical and to counter
balance leg movement our arms need to move freely. For practical purposes
such as moving through scrub with a hike pack, or through people and city
obstacles with a travel pack, the width of the backpack should not extend
beyond the width of the body. Well designed backpacks are wider at the base
(hip width) and taper to the shoulder (chest width) conforming to the natural
shape of the body. Generally in the travel packs the width would be more
square and wider at the shoulders and the depth would be a little deeper
than that of hike packs, but still not extending beyond the body width.
C11 How is the Backpack Depth and Shape determined?
To determine the backpack depth it is then simply a matter of taking
the stave length (backpack length) and backpack width to build a backpack
of the correct depth to provide the capacity we are seeking. Although we
are not limited in the depth of the pack, the greater the depth of the backpack
the more leverage on the back. This is why we do not construct a backpack
in Extra Large (Higher Capacity) with a small stave length of 50cm, or a
Net Torso Length of 38cm or 15". There is a natural tendency to lean forward
when carrying weight on our backs. By making the lower section of the backpack
with less depth and the upper section of the backpack with more depth a
more natural posture is possible. The larger opening on the throat provides
easier access and the shape does not prevent loading your backpack as required.
C12 How is the Internal Stave Positioning determined?
We first need to consider the areas of the back that are best suited
to comfortably bear weight, or the the areas of our body that have the best
muscle cover. The upper buttocks extending outwards offer the best lower
back support in the hip area. In the upper area, either side of the spine
on the upper back, and the front of the chest offer the best support. It
must be noted that the lumbar position near our spine is poorly padded and
we would avoid placing weight directly on this area. The correct position
of the Internal Staves is then tapered at the lower back, either side of
the spine or lumbar region at the base of the backpack and then extending
upwards and outwards to the padded area either side of the spine on the
upper back.
|