Parts needed to make two telescoping metal poles:
2 pc 1" EMT Conduit 10' (about $8)
1 pc 3/4" EMT Conduit 10' (about $2)
2 pc 1/4 x 1&1/2" bolt with matching wing-nut (about $1)
2 pc 1/4 x 2" carriage bolt with washer and nut (for attaching houses to pole)
2 pc 8" 16 guage galvanized wire (for attaching houses to pole)
Tools needed:
Hacksaw, vice, drill or drill press with drill bits, pole driver, level, metal file, pliers, wrench set. [Note: often a store like the Home Depot will cut the conduit to any size for free. In this case you do not need the hacksaw and vice.]
To make it:
=== Cut the two 1" EMT to 7', 8' or 9' (if you are short --5' 6" and shorter-- cut it to 7'. Taller folks can cut it longer). Use the vice to hold the conduit as you use the hacksaw. Save the short pieces for some other project.
=== Drill a 1/8" hole one inch from ONE end of each of the 1" EMT pieces. If you need to, you can use a center punch to mark starting point for the drill. Usually a small hole like this is easy to start without such a mark. Start to drill slowly, once the drill bites you can drill with more force.
=== Drill these same holes larger to 9/32" (drilling a hole in metal requires first a small hole, then the second time drill up to the wanted size). It is a good idea to file the "burr" which results from drilling in metal.
=== Drive these two pieces of 1" EMT into the ground using the pole driver. MAKE SURE THE 9/32" HOLE IS AT THE TOP. This takes about 5 minutes (less if my 19 year old son is helping). As you drive it the first couple of inches, check using the level that it is going down straight. Put the level along the conduit and check at two points around the pole, 90* apart. Drive these EMT onduit down a couple of feet till the top is at the level you want the nestbox to be. Check for level is not essential if you have a good eye for vertical. I often look against the corner of a house to tell vertical quite accurately.
=== Cut the 3/4" EMT conduit in the middle (result: two 5' pieces).
=== Attach the houses to the ends of the 5' pieces just obtained. Best way is to use one or two bolts through the box and the pole with nuts. Tighten the nuts well. I use a bolt, washer and nut at the top of the box, and a wire through the box around the pole (twist wire ends) to tie the bottom of the house to the pole. [NOTE: IT IS IMPORTANT TO ATTACH THE HOUSES OR SOMETHING TO THESE 5' POLES SO THEY DO NOT FALL INTO THE LARGER EMT CONDUIT IN THE GROUND. IT IS HARD TO RETRIEVE THEM IF THEY FALL IN!]
=== Insert the thin pole (with the house attached) into the EMT in the ground. It should be at eye level where you can inspect it when monitoring. Orient the house and raise it to the height you like it when in the raised position. Mark the position of the hole from the outer to the inner pole. Now in a similar way as before (first drill 1/8" hole then enlarge it to the 9/32") drill the thinner conduit at the mark.
=== Now insert the thin pole into the one in the ground, match the holes and insert the 1/4" bolt, fasten with the wing-nut.
本文转自：China Industry News