Kali's back is ready to smooth!
In case you didn't see the last Instructable, I'm re-making an old aluminum walker into Kali, the multi-armed Hindu goddess of time and empowerment. Her "skin" is being made out of leather scraps.This segment is about smoothing the many seams that make up her back.
This technique works for all kinds of light weight leather and doesn't require toxic glues or special equipment. I used a hard shelled mannequin as a base. But you could also use bowls, PVC pipe, a bowling ball or one of those heavy duty cardboard tubes used to shape concrete pillars. Use what you have on hand that fits the shapes you're making!
Here's the tools:
A fiberglass store mannequin torso
Lighters (1 long handled and 1 small)
Leftover scraps of elastic (about 6 yards)
Stapler and staples
Kali's leather back from the last Instructable
And a wooden spoon.
Step 1: Fire for Finishing
I took Kali outside to a patio table to work on her back. I laid the mannequin face down on a patio table covered in wire mesh. The surface was secure and it didn't matter if I got it messy. Of course, that mesh would chip the paint off the mannequin, but it needed re-painting anyway.
There were a lot of seams on Kali's back. Most of the thread ends were clipped as I sewed, but I missed a few here and there. When seams are exposed, little tail ends of thread stick out like a sore thumb and it's not so pretty. Luckily I used polyester thread, which is both durable AND meltable. I could use a lighter to melt off the tail ends.
Pro tip: different threads are good for different things. They all have benefits and drawbacks. Silk thread is lovely for embroidery but is not very durable. Cotton thread takes dye, which is handy if you want to dye something after you've sewn it together, but the thread isn't very stable and it rots with time.
Nylon thread is sturdy and strong, but the ends are super poky and can be really uncomfortable on clothing seams. Polyester thread is durable but melts with heat. Both nylon and polyester threads are bad ideas for items that will be used near open flames, since they both melt and can stick to skin. And both of them give off nasty and toxic fumes when they melt. Please! Do not melt them without ventilation and protection!
Since I was working outside and had some air flow, I didn't need to worry about the fumes. I also wasn't burning off a lot of thread, so the fumes would be minimal. I melted the thread ends carefully using both a small Bic style lighter and a long handled firestarter. Both of them work well, but the small ones get very hot very quickly. I alternated between the two until all the thread ends were gone.
I checked over the back seams for popped or broken stitches. There was one broken seam at the top right shoulder, so I pinned it to remind myself to fix it later. Then I got ready for serious smoothing.
Step 2: Wooden Spoon Smoothing
One of the key touches in finishing seams is to open them up and smooth them out. This is the sign of a well-made piece. With most fabrics, the best way to do this is to iron the seams open and flat. Leather doesn't iron very well, though. The heat and steam from an iron can shrink and damage leather in weird ways.
Most leather clothing has glued down seams. This works all right on the inside of a jacket or pair of pants, but glue can stain- and glues that work well on leather tend to be both toxic and messy. Contact cements are toxic and leave sticky, shiny residues. Spray adhesives are toxic and leave a huge sticky mess no matter how careful you are. These were not good options for the very visible seams on the outside of Kali's back.
Not to worry. The back of a wooden spoon is a perfect tool for smoothing the seams open! Since I was working over a hard surface (the fiberglass mannequin torso) I could press all the seams open without messing up the mannequin. I carefully opened up each seam with the edge of the spoon and smoothed them as flat as I could with the back of the spoon. The areas where several seams came together took a little more time and pressure, but they smoothed out nicely.
Once all the seams were flattened out, the leather back grew a little bit. Not much, but enough so the tape wasn't holding the back in place smoothly over the mannequin. It was time for a better method.
Step 3: Stapling Straps
To stretch the leather nicely over the back of the mannequin, I needed gentle pressure on each side to hold it in place. Elastic was a great choice! I had lots of leftover bits from a TV gig, so I pulled out the bin and got ready to rig the leather. There was extra seam allowance on the side seams, shoulders and bottom edges of the leather back piece. I figured I could staple the elastic pieces to those edges and use the elastic to pull the back over the form.
I started with the top of the left side seam and stapled a piece of elastic to the edge. I set the mannequin up on its base and pulled the elastic across and over its bust to the opposite side seam. Then I stapled the end of the elastic to the top of the right back side seam. It was a little awkward to shove the stapler under the leather, but it worked okay.
Next I turned the mannequin over on its back. I took out 2 more pieces of elastic and repeated the process: first at the waist, then again at the bottom edge of the mannequin. The elastic held the leather across the back horizontally, but it was still bunching up vertically. I needed to add straps at the top and bottom to keep it smooth all over. So I stapled another piece of elastic at the bottom edge of the right back side seam, angling it so it would go over the bottom of the mannequin's torso.
This added a lot of staple holes to that corner. And when I pulled the elastic across to the opposite side, the leather started to tear. Okay, maybe staples weren't my best option. Time to bring out the safety pins.
Step 4: Safety Pins Are Safer
I took out my box of safety pins and pinned the stapled elastic in place, then removed all the staples. It was a pain to shove the pins through the leather, but it was a lot more secure.
There's a lot of different tools you can use to hold leather in place. They all have their good points and bad points. Sometimes you have to try things out and see what works, because it's not always clear from the start.
Staples are great for holding things down inside of a seam allowance. They do leave small holes, but as long as those holes are inside of a seam allowance it's okay. Unfortunately they don't hold up to a lot of pressure or strain, and stapling too many times can weaken the leather to the point of tearing. Which is what happened.
Straight pins are usually not very strong, so it's hard to get the points to go through leather. And the pointy ends will snag both the leather and your skin. My straight pins were kind of wimpy, so I didn't even try to use them.
Office clips don't leave any holes at all, but they are only good for holding things temporarily. They pop off when put under pressure. Not so good with elastic.
Big safety pins leave big holes in leather, and sometimes their points are very dull. It's difficult to get them through thick leather. It can really hurt your hands, and sometimes you need to use pliers. But when the pins go through, they really hold. So that was the answer for this round.
Next up was the vertical stretching!
Step 5: Cross My Heart
I pinned a long piece of elastic to the bottom edge of the leather, right where the pieces were buckling the most. Then I turned the mannequin over onto its back and pulled the elastic across the front all the way up to the left shoulder. I pinned the end of the elastic in place, turned the mannequin back over and checked out the smoothness. It was looking good!
The next step was to figure out where to pin the elastic to maximize smoothness and minimize areas with pin holes. One piece of elastic went from the right outside shoulder and pinned back around to the left side of the bottom. Another piece went from the inside right shoulder and across the mannequin's front to the left side seam. I checked after pinning each piece of elastic to make sure the back was smooth. There was still a little buckling at the side seams, but most of the leather fit snugly to the back and I didn't want any more pin holes than necessary.
Excellent. I made a final pass with the wooden spoon to smooth out the seams and brushed off any bits of leather dust. The back could sit on the form and finish stretching out while I prepared for the next steps.
Next up: making the leather front!