Everytime I used this, someone felt the need to (in some way) tamper with it.

Still feels unnatural I guess :')

https://cdn.discordapp.com/attachments/703543641498714196/719139951802974238/unknown.png

If the sand/lead conveyors get filled up with metaglass it gets stuck.

I built 100 of this setup in a sandbox map. I place them with all possible orientations. I let them run for half of hour at background. None of them get jammed. I saved the map, reloaded, no jam. I addd 100 more Only one of them jammed this time cause i forget to wire up some of the kilns in the setup. Guys, you are probably having the same mistake. This is working fine.

I would like to see a gif or image of it, maybe even meet ingame. There is a chance you haven't fully powered the setup, or some of the smelters aren't powered.

It jammed as soon as I used it.

I haven't had it jam personally, did you have any pictures or examples of it jamming, so I could take a closer look at it?