or just print it?
It's a bit of a no brainer.
Even if you just want a shielding layer, the convenience of this will win out on low volume parts.
If you need complex parts, this could be an excellent choice.
Idk what the confusion here is. Maybe you are unfamiliar with machining?
I can't explain everything in every comment. You can research the materials if you want to understand the discussion in more context.
Tbh I have no idea how you came away thinking I said lead is hard. "also difficult". "this" is the material that is the center point of the discussion. Context, yo.
(i actually had the impression that working lead on a lathe was very easy indeed due to its softness, but i've never tried doing it myself, and my bachelor's degree from youtube is worth what i paid for it)
i think you may have misunderstood something in the comment you were replying to yourself
A little bit of lead in steel will increase machinability, but only a teeny amount. Similar to adding a small bit of phosphorus.
It's also hard to hit dimensions in lead, and if you do hit them, the second the temperature changes you'll lose them. Additionally, whatever you make can't see any stress, or the part is donezo.
Idk if you've ever handled lead - but considering you can bend thick sheets of it by hand and melt it on your stove, I'm sure you can imagine the kind of issues you might have integrating expensively machined chunks of it in to hot high pressure environments with moving parts.
Even though lead is cheap and this filament is expensive, actually getting the lead to shape by machining or working it is also a costly process. 3d printing has a sort of cost ceiling. Once a part is designed, all of the real work is done. For fabrication and machining - once the part is designed the work has only begun.
What might look like a small and simple combination of geometric shapes can cost thousands to machine.
I'd rather spend 500 on filament and a day's engineering labor on a part than the same day's engineering, 100$ of lead, and 1k or more on manufacturing. Not to mention the lead times on machined parts can be wild.
maybe an exception is that petg's maximum elastic strain is larger than lead's
Of course the petg in there is a limiting factor, but even plain petg is an order of magnitude better than lead at retaining its shape under a wide range of loads. You can print gears for lathes in petg! And they last years! (If you're wondering why you might do this - it's a good idea to have a cheap point of failure on devices that have enough power to rip themselves to shreads.)
Not to mention this is only v1 of the material. We could see exotic plastics that are far more heat resistant like PEEK get a secondary filler for niche radioactive usecases.
(at such low filler loadings the tungsten will change the modulus of elasticity very little)
petg does have higher yield stress than pure lead (53 megapascals vs. what https://nickelinstitute.org/media/1771/propertiesofsomemetal... says is 17 megapascals) but there are lead alloys that are in the same range of yield stress, including regular lead-tin solder. but they won't last if you try to make change gears out of them precisely because they're harder than petg
by the same token, though, i think you're going to get a lot of springback and long-term distortion out of petg you aren't going to get with lead
I did not, in fact, come away thinking lead is hard. I did, however, explain and spell out for you how @kragen probably did so; I'm not sure how I can make it any more clear.
you seemed to be saying that this filament might be a better alternative to lead sometimes, but i couldn't tell when that might be. pure tungsten is clearly a better choice sometimes, for example because it shields better than lead, is harder, is denser, and is more refractory, but none of those seems to be true of this filament
from your other comment at https://news.ycombinator.com/item?id=35206874 it looks like you're saying that, although this composite is inferior to lead in those ways, it's easier to print
For the right application, there are some good wins here.
what do you think about copper-filled or baryta-filled filaments as cheaper alternatives
maybe this is wrong but i feel like both tungsten and copper are in the 'if you have it embedded in your body you are going to need surgery to get it out before you get gangrene' while lead and baryta are not