How can I estimate where the drill point will come out when drilling an angled hole through a wall?

Angled holes are tough to pull wires through because the cable catches on the sharp edges.

1. Before beginning any project, plot out exactly where large pipes and ducts will run and determine how you'll get them there.
2. Wherever possible, run large pipes and ducts vertically into unfinished attics or basements, then install elbows and run the pipe or duct horizontally below the floor joists or above the ceiling joists.
3. Build 2x6 stud walls where DWV pipes and holes exceed the limits shown in Fig. A.
4. Rent a right angle drill and use Selfeed or hole saw bits for boring large holes (Fig. B). The right angle drill allows you to drill holes square to the stud face. Holes drilled at an angle will wind up oval and therefore larger.
5. Drill holes at least 1/4 in. oversize, especially for hot water pipes. If you don't, they'll make annoying sounds as they expand, contract and rub along studs.
6. Joist hanger manufacturers sell wrap-around, stud reinforcer plates (Fig. A). Ask your inspector if they are permissible in special situations.
7. When boring electrical holes, keep them square to the stud for easier wire installation, or pulling. This may seem trivial, but angled holes like those shown in Fig. C “catch” the wire and keep you from pulling wire through more than two or three studs at a time. Holes in a line (Fig. D) let you pull wire through an entire wall length of studs at one time.