I am smiling, because I am imagining you being all Steampunk with your antique glasses and your amazingly custom-made magnifying lens attachment. Which is all *working*, not cosplay. Now I'm wondering what you're making that you need a magnifying lens to assist you...
:) It makes fitting bristles to my hand rolled threads, namely piercing the fine thread for locking off the bristle (right towards the end of my thread making video), very easy. I have ordered in another lens, which I will be able to fit to the opposite arm of the spectacles, to give me binocular vision, and will see what can be achieved in regards fine sewing with them. I am beginning to learn about watch and clockmaking, but have found it very useful for adjusting a Russian circular sliderule and doing some very fine turning on a watchmaker's lathe (known as a 'Turns').