this post was submitted on 26 Dec 2025
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It's only $300 dollars and I never pay for glasses again.
It pays itself off in 3 years.
Maybe I can 3d print frames too. 
I was curious whether it was actually simple to duplicate a lens, so I started to look into how this works and I’m afraid you’re missing a couple steps. This machine only enables you to grind the edge of another lens to match an existing one, so you still need a lens, just not in the right shape yet.
I assume that when you get frames, they also send a model lens for a machine to copy, I don't know how lenses would get made any other way.
I think they're saying that this doesn't make the prescription. This copies the shape of the model lens but you need to feed it both the model lens and a finished prescription lens made by another machine so that this machine can cut out the needed shape.
In other words, you still need machine to grind the precise prescription into a circular blank I presume.
Yes, exactly.
E: whoops, didn’t mean to switch accounts
E2: oh, now I remember why that happened. Please come back online hexbear 🥲
Hmm, how much more do you suppose that is?
I have no idea what the machine is even called haha. It probably depends on whether you need just spherical or if you have astigmatism and need a cylindrical axis too.
You could probably partially DIY it with enough time and effort, huygen optics on YouTube does something like that, idk how complicated it is to make an astigmatism prescription.
I've thought about DIYing some of the glasses process, but only the diagnostic part. You can get that machine that lets you try basically any prescription for under like $1k, so you could use that to adjust your prescription and then try to order the actual lenses through somewhere online. Lens grinding seems tedious if you're doing it by hand without an expensive automated machine.
This might be a bit cheaper. More analog.
https://gv2020.org/partner/
At a glance it looks like they only have 3 different strengths and no provisions for astigmatism. My interest is in fine tuning my prescription in increments of 0.25 as well as fine tuning my astigmatism in several degree increments so it wouldn't be of much use to me.
Edit: For anyone else curious about doing this on a budget, check out "trial lens sets", it's just a case of a couple hundred lenses you can get for around $200 that includes close to what looks like every prescription under the sun, including astigmatism and prism(!!). You're be manually swapping, stacking, and keeping track of every strength but it has strengths as low as 0.12 and looks like they include frames to pop them into.
I bought a trial lens kit from Amazon and printed an eye chart and then returned the kit afterward.
Still couldn't buy the glasses I needed without the prescription because they cracked down on the Internet sites that let you do that, but it was a cheap way to know I needed glasses before spending the money on an eye exam.
Sure, but all this machine does is cut the edge off one lens to match another, you still need a lens with your prescription that has been properly centered for cutting to the shape of your frame.
Oh how they keep the means of production away from me