Cleaning muddy abs

Greetings..

My Drain lines are dry fitted in muck below where the slab used to be.. My question is how clean do I need to make these to glue.. When I clean with a rag, they end up a bit rough.. I was thinking about hitting em with some 400 grit as a final clean up. Is this adviseable... How forgiving is the ABS glueing process?? I also read that the pipes slide together easier when the glue is on and may go in deeper than they want to do on the dry fitting..

Thanks in advance

Why dry fit?
Every joint changes by at least 1/2" when you cement it...

Thats good to know.. We have a pre-glue and inspection, then a post glue leak test as well as ground work. It is a tight space in a basement and includes redoing the drains for the main floor bath, relocating the washer and dryer. The pre-glue inspection is Monday..

Dirt is not friendly to ABS cement, and neither is any moisture.

inspection

I have never heard of a "preglue inspection". I think the inspectors would be run out of office if they expected us to assemble the whole thing and then take it apart to glue it together. Besides the problem with everything eventually coming up TOO short after gluing them.

My guess is you misunderstood what was meant about a "preglue inspection". PVC and ABS can not be dry assembled. The pieces will not slid all the way in and if it did, you'd never get it apart. I would bet they wanted to inspect the layout including all the pipe and fittings before you glued them.