Comment on My personal benchy: this one really tests a printer's capabilities

swizzlestick@lemmy.zip ⁨4⁩ ⁨days⁩ ago

• ExtremeDullard@lemmy.sdf.org ⁨4⁩ ⁨days⁩ ago

  Thanks for the offer! But actually I didn’t model that part for me but for others who need a model of a finished lens. I already have real lenses myself.

  The thing is, I shared the design of my glasses for others who might want to print themselves the same glasses too, and there seems to be enough interest that some folks printed them and went to their opticians with it, only to be turned away because the frames are unusual - or they didn’t want to risk having lenses made using the lens template only to find out that the lenses are unusable in the final frames - and they didn’t want to risk filing a notch in the lenses either, which is something that’s not usually done to fit lenses to frames.

  And I can understand the opticians too: if they agree to order lenses and they don’t fit the frame, the loss is on them and they don’t need the aggravation.

  I wanted to provide a model of a lens that those folks could print out of PLA to convince the opticians that it’s not sketchy or far-fetched. If this parts needs a resin machine - which, I agree with you, it absolutely looks like it does if you really want a quality part - then it sort of defeats the point of self-sufficiency of my little project.

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  • dual_sport_dork@lemmy.world ⁨4⁩ ⁨days⁩ ago

    The other point here is that if the lenses a user gets don’t quite match the frame you could always just tweak and reprint the frame a bit to match the lenses. That’s not really the end of the world, but I don’t count on any opticians to understand that. The concept of a user being able to so easily self manufacture a set of frames is probably completely alien to them.

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    • ExtremeDullard@lemmy.sdf.org ⁨4⁩ ⁨days⁩ ago

      tweak and reprint the frame a bit to match the lenses. That’s not really the end of the world, but I don’t count on any opticians to understand that

      Oh believe me, they understand perfectly.

      Here’s the thing - and I’m not inventing this: my current optician is a friend and she told me this verbatim: an optician’s bread and butter is selling you frames, and the services around fitting the lenses on the frame and fitting the frame on you. Opticians make almost no money on the lenses - which they have made abroad in developing countries usually.

      I don’t deny that there’s a lot of measuring prior to ordering lenses, counselling the customer, and then a lot of fiddling with the temples and the nose pads after the glasses are completed to make sure the glasses are comfortable and yada-yada. The services provided by opticians are definitely useful, particularly for young wearers and for people who change frames often.

      But really, if you’re a lifelong glasses wearer, you’re reasonably handy and you settle on one frame geometry, those measurements never change and you just don’t need the services.

      Me, the last time I needed an optician’s services was over 20 years ago when I made my first frames out of nickel silver. Since then, I’ve only made copies of those exact frames because I really like them - including those 3D-printed ones I drew a few weeks ago: they’re a bit different to account for the nature of the 3D-printing process, but the key measurements are the same.

      So whenever I go to an optician to order new lenses - which you almost have to because you can’t order the lenses direct, even if you have all the measurements needed by the lens maker, the convo always goes something like this:

      • Hello, I need a pair of lenses with these dimension (or for these frames), with this prescription. My pupillary distance is x, the vertical angle is y, the bevel is z all around and the optical axis is marked here. I don’t want you to mount the lenses on the frames and I don’t want you to fit me. How much and when?
      • Well okay, the lenses are $something. But since you don’t buy frames from us, we’ll have to charge you an extra $something.

      I kid you not, it’s extortion. They hate it when you can do their job yourself so they charge you for the privilege. And since you don’t have access to their suppliers (they look out for each other) you have to go through them.

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  • HumanPenguin@feddit.uk ⁨4⁩ ⁨days⁩ ago

    Sounds like the eventual end. Will be learning how to take raw circler optical lenses. As the optical centres do. And build the tools for folks to shape them at home.

    Such a project would be a huge advantage to many 3rd world environments. And would likely be about embedding quality glass cutting blades etc into 3d printed frames/mechanisms. Likely from PA. With the ability to embed metal rods and gears where stability, strength is needed.

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  • swizzlestick@lemmy.zip ⁨3⁩ ⁨days⁩ ago

    You’re welcome - glad to see you have it really sussed out. Finding something that works for you and knowing it won’t just up and disappear off the market (as many fashion frames do) is excellent.

    Can see the optician side as well - they have an established process and deviating from that is unwanted faff. However, they are perfectly capable of ordering a lens to a customer given spec. A short ‘if this doesn’t work then lol you suck’ disclaimer is all it would take to make the sale.

    Resin is well within reach of the casual hobbyist now - we’re talking a couple hundred dollars to get an entry level machine, and a little extra coin for the materials/consumables. I have a (now old) Mars 3 that is ticking along beautifully.

    Safety/PPE/ventilation is the main downside compared to FDM. It’s a stinky job but you can’t fault the results for presentable and functional parts. These things can print stuff like screw threads and other teensy features perfectly.

    Offer always stands if you ever want something to demo and can’t get anyone more local to help :)

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    • ExtremeDullard@lemmy.sdf.org ⁨3⁩ ⁨days⁩ ago

      Resin is well within reach of the casual hobbyist now - we’re talking a couple hundred dollars to get an entry level machine, and a little extra coin for the materials/consumables. I have a (now old) Mars 3 that is ticking along beautifully

      I am very tempted by a resin printer. However - and this is going to sound weird - I actually like the limitations of FDM.

      And this is why: I’m a hacker at heart (in the old sense, not the nasty illegal stuff) and I like to push the envelope of what our Prusa Mk4 printer can to. I’ve printed stuff with that thing that I had no right to print by working the workarounds in the model, playing with layer sizes and controlling the path of the nozzle so it ends up printing features that are right at the limit of what it can do. Hell, even the hinges in those specs of mine are kind of pushing it.

      And it’s fun! It provides hours of good fun trying and or that and finally getting the little printer to print something right.

      A resin printer would make very good prints without anything to do, if that makes sense 🙂

      Also I want to work with different materials. I’m actually looking into getting a Prusa XL with several heads to combine TPU for flexible, hollow parts and PLA for the supports inside the parts. That’s something a resin printer can’t do: resin printers print… well, resin.

      And finally, I’m always kind of designing parts with a view to making it available to anybody who has any old printer at home for them to print and enjoy. That approach entails designing for the lowest comon denominator (to a reasonable degree), something a resin printer is not.

      So you see, while I would like a resin printer, I feel it’s just not the right printer for me.

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