Lens cap Saturday

[Graham06]

Would you like to have nice snug, leather lens caps for all your large format lenses? It is really not all that hard to make them. I just made another half dozen on a whim.

• You need some thick veg tan leather. e.g.

https://tandyleather.com/collection...-to-9-oz-2-8-to-3-6-mm?variant=34100261126275 ( each piece of leather is unique, so visiting a real store is better, but online places are fine)

• Find or make a round cylinder, with inner diameter 6+mm larger than your lens ( you'll be surprised what you have lying around). I've used string before or a pipe clamp.
  
• wrap your lens in saran/cling wrap. removing the element you are making a cap for helps. It will be in contact with damp leather for a few hours, and there will be a degree of wrangling to shape the leather so if your lens is too delicate make a form of exactly the same diameter. I am reasonably good and not breaking things, and so I mostly just use the lens in cling wrap.
• Cut a rough piece of leather with enough space for the sides and additional space to tie string around it ( if you use string, it will leave marks, and so you tie it on leather that will be trimmed off
• Wet the leather in room temp water for a minute ( it will become noticeably floppy. and then dry off excess moisture with a paper towel,
• Form the leather around the lens (or form.) As you work with it, it will take the shape you need. Use your outer cylinder, or string to tightly form the leather wound the lens with more than enough to cover the sides. Make sure there are no crinkles.
• When it is all tied up, leave it to mostly dry ( e.g. overnight )
• Once it is mostly dry, remove the outer clamps, and mark a cut line. remove the inner form or your lens so you don't scratch it and cut off the excess. A really sharp knife helps.
• Dye the outer an inner surfaces. ( I use dark brown and black) https://tandyleather.com/products/f...2&_sid=ff2f0a74c&_ss=r&variant=32105316712579
• Burnish the edge https://tandyleather.com/products/eco-flo-gum-tragacanth?_pos=1&_sid=3c3781c9c&_ss=r
• Leave the cap off the lens to fully dry. it will shrink just a little ensuring a snug fit.

I was sure I wasn't the first to do this and google shows me this page which seems like more or less what I did, though it seems a bit more fussy. https://www.refracted.net/lens-caps.html

Attached are pictures of today's work in progress and some lest caps I have made in the past.

Usually the first thing I make mostly works, but it reveals many mistakes, and process improvements, and then the second one is much better, once I have a good feel for things, so make just one the first time around

 

[Graham06]

Would you like to have nice snug, leather lens caps for all your large format lenses? It is really not all that hard to make them. I just made another half dozen on a whim.
Leave the cap off the lens to fully dry. it will shrink just a little ensuring a snug fit.

This should really be "Leave the cap on the lens to fully dry. It will still shrink a little, but if you leave it off, it risks shrinking too much.

Finished all 6 caps ab hour into Sunday. Spent most of yesterday working and waiting for various drying steps, and finished the last dying, polishing and burnishing this morning. A few shrank more than I would have liked overnight, but no real failures. If you wet the leather in boiling water, it will thicken, shrink and harden very soon after becoming flexible so be careful. It will yield much harder caps, but I find the slight flex if you use only cold water perfectly acceptable. Water based dye leaves a slight green sheen, but clears up nicely with some dubbin wax.