Probably caused by walking far enough away for the chunks to unload client-side, and walking back?

The pipes have a collision box, but do not ray-trace and do not render.

This is an annoying reoccurring issue with most tile entities I think, but they show up if you place a block next to them. I wasn't aware this happened when you walked far enough away as well though...

maybe just force a blockupdate when it recieves it's desc packet clientside?

That's not the issue @AEnterprise , the issue is that the client doesn't receive a desc packet from the server- it doesn't know that it needed to send a packet at all, so the client does its best with an invalid pipe and doesn't render it.

@AlexIIL that's very odd, when a TE is loaded on the client side the server sends a desc packet to the client, if it's not doing that then you're eighter blocking that (by accident) in the code or there's a forge bug

I'm was blocking that on purpose and just sending out a BC packet instead of a normal MC packet, however in my dev environment I'm testing sending an MC packet and it seems to be working.

What's the current status of this, @AlexIIL ?

Yeah I haven't encountered this. But it could be a duplicate of #3238.

has this been fixed? the commit and lackof other reports sugests so