LAY FLAT KETTLE
This post describes a backpacking ultralight lay flat kettle that is made of silnylon, RTV silicone rubber and copper foil.
INTRODUCTION
My ultralight lay flat kettle (~31 g) for snow melting and water boiling is made of copper foil and silnylon and it has a capacity of ~700ml. The base provides good heat transfer and the wide opening makes it suitable for snow melting and boiling water for hot drinks, soups and noodles etc and will lay flat for ultralight backpacking.
Extreme ultralight backpackers sometimes resort to a ‘cold menu’ without the requirement for cooking. However, when the trekking is over, I enjoy my abundant hot drinks for hydration, relaxation and socialising. I also enjoy nutritious sustaining hot meals to replace the energy used during the journey. Consequently, an ultralight and compact kettle would make interesting backpacking kit.
THE LAYFLAT KETTLE
The lay flat kettle can be used for snow melting and boiling water for an ultralight backpacker. It can also be used to supplement conventional cooking pots by allowing the making of hot drinks and soups while a dehydrated dinner is being prepared in a pot.
The lay flat kettle partly removed from its flat pack that also carries other flat items such as the gland for the flue pipe for the tent stove and the plastic tent window. The loop on the green flat-pack allows it to be carried securely on the backpack in a protected area such as the hydration pocket.
Lay flat kettle deployed (popped up). The 31g kettle that holds 700 ml of water. It has a wide mouth for loading with snow to melt to make water.
HOW THE KETTLE WAS MADE
I use cheap acetic acid cure silicone rubber bathroom sealant (from Bunnings or Aldi). I prime the silnylon fabric with thinned silicon rubber and sand the copper foil where joints will be formed to clean and roughen the surface for good ‘keying’. After quickly applying the glue to both surfaces, I press them together and fold a thin flap of the copper foil back up on to itself using some thin (0.3mm) SS foil as a straight edge to hold the doubled over silnylon deeply in the fold. I push some more rubber into the fold. I quickly work around folding all sides. Then, starting with the first side, I fold them for the second time (to strongly lock the fabric in) and apply more rubber to the folds just before I crimp them closed between strong straight-edges. I wipe off the excess glue that squeezes out inside and outside the kettle. I presume that the joint is watertight because there is either a strong bonding to the rubber by both components or a rubber gasket forms in between them. For more on glueing please see silnylon glueing.
Tim
Hi Alan, Sorry I did not reply sooner, I will blame the good ski season. Thanks for your encouraging comments. I will put the answer in the body of the post.
Tim
Hi Alan, I use acetic cure silicone rubber for the seams (the cheap big tubes of bathroom silicone from the hardware store). I prime the silnylon with the rubber and sand paper the copper foil where the seal will form and after applying the liquid rubber I quickly close the joint and roll the two joined edges and press flat with flat piece of metal like a steel rule. It forms an effective sea whether it is by ‘glueing’ or forming a gasket. In my experience, not all silnylons are equal in glueing qualities, so you may be interested my other post on this. I will add this to current post
https://timtinker.com/silnylon-glueing/
I would also like to hear of your experience with glueing silnylon, and particularly if you can find/define the factor that makes it good or not so good for glueing.
Tim
Hi Tim, could you show and / or explain how you accomplished a watertight metal to silnylon seam? I’m interested in more construction details. I really enjoy your innovative ideas. Keep them coming!
Hi Tim, could you show and / or explain how you accomplished a watertight metal to silnylon seam? I’m interested in more construction details. I really enjoy your innovative ideas. Keep them coming!