Glueing instead of pinning for sewing backpacking tents
This post is about glueing instead of pinning in preparation for sewing light backpacking tents from light and slippery fabrics.
If you are a part-time or crap sewer like me, you will probably understand the difficulty and frustrations of sewing lay flat seams on backpacking tents. I make pyramid tents with many strong lay flat seams that are load-bearing. The cut of the fabric and the pairing of straight grain with bias grain makes the seams strong and makes all seams have a uniform and limited stretch. The unwanted stretch of the bias cut portion of the seam is particularly difficult to manage while making the first row of stitches.
My start to forming the seam is unconventional and it helps me manage the stretchy fabric. “Taught to me by Mum who was a professional seamstress, who made sewing look easy.” I wrap the taught straight grain around the bias cut edge to make a stable sandwich of the troublesome stretchy edge. (Described in Lay flat seams for pyramid tents.)
Frequent pinning of the seam in preparation for the first difficult line of sewing is necessary but not easy with slippery thin fabrics. “The points of the pins also make bad company while handling a growing tent canopy and passing the seams through the sewing machine bridge.”
I have experimented with practical uses of RTV silicone rubber to glue materials for DIY backpacking gear. Some materials form strong bonds and some form weak bonds with low peel strength. However, most fabrics form a bond that is strong enough so that it would serve as a substitute for pinning or tacking when sewing the many lay flat seams (18 Meters in total) while making a strong pyramid tent canopy.
Lastly, I was making a new experimental tent with a breathing polyester fabric (with poor glue bond strength) to hopefully eliminate the pesky condensation problems associated with my favourite silnylon pyramid tents. It became an opportunity to test silicone rubber glueing as a substitute for pinning. “The Covid19 close down of our ski season is another contributing factor.”
Experimental preparation of lay flat seams by glueing instead of pinning
To make the next glueing clamps, I made little double-sided pressure plates out of rectangles of stiff non-stick plastic sheet. (From cheap supermarket ice cream container lids.) These were `20mm wide and were folded in two and were ‘crunched’ with pliers to flatten and ‘break’ the bend, leaving the two plates hinged together.
I spread a tiny amount of the RTV acetic cure silicone rubber onto a point on the seam and smeared the glue over the contact surfaces at that point. Then I closed the seam and squeezed the fabric between my fingers so that the glue spread thinly along the seam for about 20mm. I placed the hinged plastic clamping plates over the glued portion of the seam that was then laying very flat. Initially, I clamped the glued zone together with clothes pegs. “I quickly found that this apparently complex procedure was actually quite easy. In fact, much easier than doing the equivalent job of quality pinning.”
Temporary clamping in preparation for glueing instead of pinning
I should mention that I mark seam datum lines on all my tent panels when I am preparing for the cutting out. These give me critical points that must coincide when forming the seam between the stretchy and the low stretch portion of the seam. The above-mentioned clothes pegs allowed me to set the seam up quickly according to the datum lines before any glueing was started and minor adjustments could be made.
My new tent design has rather radical corners where the roofline seam ‘seamlessly transition’ to the dwarf wall of my particular pyramid/bell tent. The bend in a lay flat seam needs to be ‘eased’ to round this bend (as an alternative to cutting a ‘dart’. I found that this easing was easy to do with glueing, so that sewing through the bend ‘easing’ was subsequently very easy.
Improved compact glueing clamps
While the pegs worked well enough, they were bulky and they did not provide a strong enough compression force to the glued zone.
Next, I made some simple clamps out of scraps of feisty ‘tray-deck’ roofing steel. I cut off the corners of the ends of the clamp and bent them outwards so that they could smoothly ‘slip’ over the pressure plates after the glue had been applied.
I knew this was a winner, as I found I could wrap and squeeze together the glued section of the seam within the pads while I simply slipped on the clamp. It was easier and less disruptive of the seam alignment than any pinning that I had previously done. It would be held securly when it came time to sew through the zone without the disruption of removing pins.
Mothy The Elder
Fast cycling of glueing clamps
The new clamps were strong and compact so that, I could do the glueing, have a cup of tea or do some other minor sewing task and then impatiently start sewing the seam before the glue was fully cured. I found that I could just sew along and pull off each clamp and throw it into a bowl as it approached the sewing machine foot. The glued sections were very easy to sew through.
Lay flat seam sewing had never been easier, for this crap-sewer, and I could concentrate on the simple task of sewing. It was almost a pleasure!
Mothy The Elder
Tie-out sewing with glueing instead of pinning
For years as an alternative to commercial webbings, I have used DIY light tent tie-outs that are made of a four-times-folded strip of the tent fabric. I sew the long strip down the middle to hold the folds together prior to attachment to the tent. The ripped-off selvedge edge of the fabric roll with cosmetic defects makes excellent use of this otherwise wasted part of the fabric.
They are so small that they are difficult to pin in place prior to sewing onto the tent seam. Could glueing with acetic cure RTV silicone rubber instead of pinning work in this situation?
Please see Tie-out tabs for pyramid tents for more information.
MORE ON ADVENTURE GEAR GLUEING
If you are a DIY adventure gear nerd like myself, you may be interested in my other glueing posts. However, before them, I thought a little ode about the fluid meaning of ‘nerdism’ would be fitting.
I tinkered in my shed like a passionate knurd, Or should I use gnurd, a more gnarly word, Or nurd, another old and similar pejorative, Meaning of all, now have morphed into positive narrative, So with obsession and a touch of pride I embrace the term nerd.
Glued repair to adventure gear
RTV silicone rubber, Oogoo, Sugru, Kintsuglue and Tommy tap comparison
