advice

I am building my first dd any thoughts on where to deploy the main chute midpoint or nose?

Having done plenty of both I would say start wih the traditional payload bay deployment.

are you asking if the main should be in the front section or rear section? or are you asking if the front section should separate at the nose or av bay? I like to have the main in the front section, so at apogee the rocket separates at the middle. that way it is less likely to stabilize and go ballistic. then I blow off the nosecone for the main. you want the deployment charge to blow the chute out of the tube.

If you are asking where to position the separation for the main, I use mid-point above the av-bay and fix the payload tube to the nosecone. Unless you need to add weight to the nosecone for stability, the cords / glue / fittings can be somewhat on the light side at the nosecone end compared to the booster end. Just make sure the main-to-av-bay connection is stout.

My L1 rocket is a "traditional" DD rocket, and I have been blowing the nose for the main. However, as I've gotten better at packing chutes the main inflates more quickly, and now it is prone to zippering...the last of which was 4" long. Since I needed to make a new payload tube I reversed the screws and the shear pins, so it will separate at the electronics bay (midpoint) in the future.

For me, I break rockets near the (assumed) mid-point at apogee (drogue or drogue-less) and deploy the main from the payload section @ nosecone.

What are you building?

How about taping the harness or chute lines or spill hole?