Skinning the kayak - pulling out the concaves
Pulling out the Concaves
The last blog ended with the fabric - pinned at the keel, developing concaves between the chines due to the amount of its longitudal tension. It has been my experience that the considerable force required to flatten the fabric also tensions it around the boat.
As just grabbing the fabric and pulling can distort the weave of the fabric, I prefer to wrap a batten around the piece I am about to tension before pulling it tight. In this fashion with the boat upside down I tighten from the keel downwards one chine at a time. Thus I end up with a row of pins on the first chine stringer holding the fabric in place.
It is important to insert the pin all the way to the flat top of the drawing or upholstery pin so as to prevent the centre of the pin from pulling a hole in the fabric. If the pin does not go in easily first time it is probably best to re-insert it until you find the decreased resistance between the hard winter wood of the growth rings. I find that staples can chop through the individual fibres. Although that is not a problem with a natural fabric such as canvas, it is with polyester which tends to slip over itself.
Once the fabric is secured to the chine stringer, then the pins can be removed from the keel and the process repeated until the fabric is secured to the gunwale.
I use two hands when not taking photos, one pushing down on the gunwale and the other pulling the batten and fabric up and over until the pins are in place.
Above shows the redundant chine stringer pins being removed.
Pinned to the gunwale. Most of the creases are due to slack between the pins which should be addressed when the tension comes from the seam. The boat is now ready for sewing the seams - next post.
The last blog ended with the fabric - pinned at the keel, developing concaves between the chines due to the amount of its longitudal tension. It has been my experience that the considerable force required to flatten the fabric also tensions it around the boat.
As just grabbing the fabric and pulling can distort the weave of the fabric, I prefer to wrap a batten around the piece I am about to tension before pulling it tight. In this fashion with the boat upside down I tighten from the keel downwards one chine at a time. Thus I end up with a row of pins on the first chine stringer holding the fabric in place.
It is important to insert the pin all the way to the flat top of the drawing or upholstery pin so as to prevent the centre of the pin from pulling a hole in the fabric. If the pin does not go in easily first time it is probably best to re-insert it until you find the decreased resistance between the hard winter wood of the growth rings. I find that staples can chop through the individual fibres. Although that is not a problem with a natural fabric such as canvas, it is with polyester which tends to slip over itself.
Once the fabric is secured to the chine stringer, then the pins can be removed from the keel and the process repeated until the fabric is secured to the gunwale.
I use two hands when not taking photos, one pushing down on the gunwale and the other pulling the batten and fabric up and over until the pins are in place.
Comments
Post a Comment