Well, after a very nice day off yesterday, today was eaten up by doing this small thing and that one and another one, all good and necessary, but somehow it led to me not getting done what I wanted to do today. Mind you, my brain was quite scattery anyways, so the flitting from one small task to another suited the day's mood, but still - the main task for today did not get dealt with. (Yet. I am planning to squeeze in a little bit more time to at least get it pre-organised.)
Part of today's planned and not-yet-done task involved calculations on the costs of fabric reconstructions. Only approximate ones at the moment, but they are still complex to do, and need some brain power and checking of lists (of previous similar, or sometimes not-so-similar tasks), and checking of material availability and costs.
On a similar vein - I've been asked if the membrane thread will eventually make its way into the online shop. Ah. Well. Theoretically... it could. But practically... I'm not convinced it will be a well-selling item. It will, however, definitely be a very, very pricey item.
Membrane strip, wound up, my current favourite tool for cutting it, and a little helper card - this time not for yarn thickness or twist angle check, but for strip width check!
The easy part for calculating the price of membrane silver thread like this is adding up the material costs. There's the goldbeater's skin as the basis, the parchment glue (which has to be prepared, too), the leaf silver, and the core thread. The core thread I currently use is vintage linen yarn, and I can't really remember where I bought it, but it's possible to find comparable yarn and see how much that costs. For the rest, I have the numbers... and adding them up, they are not pretty. But that, of course, is only the first part of the calculation process.
Now that I've more or less gotten the hang of cutting the strip and winding it around the core, I can do some time measurements for how long things take, and add those up. For the gilding process, though, I will have to estimate - I have not done that often enough yet to have a good established process, and the last approaches at stretching the skin in a frame for the glueing and gilding did work, but took a disproportionate amount of time.
Those bits in the calculation process are the hardest for me. I don't want to shortchange my customers, but nor do I want to end up with a much lower wage than intended because I underestimated the time necessary by a lot. And unfortunately, when you do those estimations for work time, that is very easy to do.
So... I've made a rough guess on where I will end up, per metre, if I calculate properly. I can tell you that the material costs for about 30 metres of thread are at around 40 €. Added to that is the work time necessary to do all the steps from naked membrane to finished thread: Framing the membrane, treating it with glue, gilding it, glueing it into a cylinder, cutting the strip, preparing the core thread (which means winding two single yarns onto a spindle), and finally wrapping the core thread with the cut strip.
Want to guess along with me? Then let me know in the comments where you'd see the price for a metre of the membrane thread end up!
