Simple, DIY, Leather Scope Lens Caps

I see Cottis is turning out very elegant, professional looking sets though if one wants a DIY solution and lacks the talent or inclination to make a stitched pair, pressed is the way to go. Been thinking about this method for years, finally tried it. For a Swarovski 3-9X36, the objective and ocular diameters are about a 1/16" off, still easily served by the mold made by a 1 7/8" hole saw and it's plug when using 4-5oz veg tanned leather, which needs to be between 1/16" and a slightly scant 3/32" thick. A drill press makes cutting the hole, preferably in hardwood, much easier though it can be done with a hand drill if your board is securely clamped or screwed down, one proceeds slowly and is able to keep the bore plumb and square-this isn't easy but I've done it. Soak the leather in cold water till saturated, lay over the hole with enough excess to form the sides--I made this set about 3/4" deep--the thickness of the maple board. Use the plug cut out as the piston and pound in with a hammer on top of a flat surface: R0275333.webp
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I let those dry next to the woodstove for about 2.5 hours, rotating sides as the leather dried to a rigid state (why one doesn't dry wet leather boots near a heat source), then popped them out --another plug may be helpful here. I waxed one of the plug pistons which was easier to remove when dried. For finishing sake, I didn't wax the hole side which would prohibit uptake.

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Trim off the excess then cut to uniform height using the handy jig made up here, that Astra razor blade deflected too much so I switched it out for an Exacto blade screwed down in similar fashion, projecting out a bit more than the thickness of leather. With the plug piston still in place rotate the cap around the blade for a uniform cut.
Voila--finished with Fiebing's Vintage Gel in Medium Brown and some Obenauf's HD LP:
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Within a few hours of final drying, they shrink a bit, whch made for a perfect fit (use sand paper to open them up if they get too tight), They are snug enough to stay put without retention of sorts. With a bit of figuring diameters of objectives, oculars and available hole saws, combined with leather thickness, I'm sure this method will serve for a variety of scopes. Barring that, see Cottis! I would have if I were on that side of the pond or we didn't have ridiculous tarrifs in place.
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Good work that man. It is called wet moulding and you have done it very nicely indeed. Nice dye as well. And a nice scope. All round top job.

For future efforts if you were to do it again on another scope, in order to attain a perfect tight fit, you could make your mould undersize slightly and continue as you did. Then when they are dry and formed, moisten them again and put some thin veneer of clingfilm (saran wrap) on your scope ocular and objective bells to protect them and then force the caps on. As they dry again, they will form tightly around the circumference.
 
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I make a few bits from leather and find a visit to a few charity shops will get me a good leather satchel/soft briefcase for a few quid. Lots of leather to use.
 
Good work that man. It is called wet moulding and you have done it very nicely indeed. Nice dye as well. And a nice scope. All round top job.

For future efforts if you were to do it again on another scope, in order to attain a perfect tight fit, you could make your mould undersize slightly and continue as you did. Then when they are dry and formed, moisten them again and put some thin veneer of clingfilm (saran wrap) on your scope ocular and objective bells to protect them and then force the caps on. As they dry again, they will form tightly around the circumference.

Good call! I've used the saran method for knife sheaths and pistol holsters, it does work great!
 
I did this for one of my scopes. As an experiment I then brushed wood harder into the leather from the inside. Turned them into very rigid little caps that don’t go soggy in the rain.
 
I did this for one of my scopes. As an experiment I then brushed wood harder into the leather from the inside. Turned them into very rigid little caps that don’t go soggy in the rain.
Good way to go. I used numerous coats of Waterlox on my first experimental run to stiffen a thinner piece of leather. It's a resin modified tung oil that dries but probably not like wood hardener would, nor do I gather Waterlox is as water resistant. Though when out in any weather, it'll be wearing the see through caps.
 
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