How to angle ABS

This may seem like a ridiculous question... but I am wondering...

What is the proper way to angle horizontal ABS drainage pipes?

If you connect the pieces, they seem to want to stay straight.
Example: Connect a vertical pipe to a 1/4 turn and add in a horizontal pipe, the horizontal pipe wants to stay... well.. horizontal. If you try to angle it, it pulls out of the 1/4 turn a bit.

I assume this is the way it is supposed to be and is why the collars are deep and the solvent helps make the seal.

How do you know that the pipe is on too much of an angle?
The reason I ask is because I have to juggle some angles when trying to tie new pipes into old.

At the 1/4" per foot for drainage, that is about 1 degree (or so I think).

If there is a post that already addresses this, please point me there. This isn't an easy subject to search.

Thanks!

Both ABS and PVC fittings have what is called the angle of acceptance but in practice knowing whether or not you have exceeded that angle is pretty difficult.

The hubs, once the glue has been applied has a fairly large tolerance for deflection. 1/4" per foot is a 2% slope, but that is a minimum. You can exceed it if conditions require it.