I prefer to use the plastic anchors also whenever I can.
I prefer to use the plastic anchors also whenever I can.
Tapcons will go in very well once you get the knack for it. Since construction here is entirely concrete these things are pretty much the fastener of choice. I can set them with and almost perfect success rate. Out of the last fifty I've installed I've probably had one spin out due to a wallowed out hole and thats because I had to back it out after the first try. Using an impact driver also helps greatly at setting them with success.
I usually avoid the phillips head ones since the torque required to set them is really not suitable for a phillips head. If it must be phillips then I only use the 1/4" taps that use a #3 head. The larger #3 tip is far more difficult to strip and a lot less likely to jump off the slot when setting it. Almost every single stripped head I see is because a #2 tip was used. Thats a guarranteed way to strip it and the number one reason I see for people complaining they strip out easily.
As far as the drill bit, there's nothing special about the one provided in the combo packs. It's just a regular 5/32" or 3/16" (depending on the screw size) masonry bit of average quality. Use quality masonry bits like Dewalt or Bosch which will make a clean hole of the right size with less effort. Cheapo bits are a lot more likely to wallow out the holes since the user will force them around more when drilling. Another thing I find is rotary hammers are not always the ideal tool to drill the hole unless the concrete is hard enough a hammer drill will not be able to make it easily. The hole needs to be just the right size and the impact blast from a roto hammer is strong enough to just oversize the hole enough to compromise the holding strength of the screw. I always try the hammer drill first. In the other extreme, when the concrete is way too hard then a roto hammer is the weapon of choice. Struggling with hammer drill in that situation, the user will tend to lean into the drill hard forcing the bit to wobble around and flex wallowing out the hole.
Once installed right they offer one of the strongest methods of fastening anything to concrete. It's about comparable to an epoxy bond. Far superior to rubber anchors.
Another thing that will keep your boxes hanging forever is hammer pins, or sometime called drive pins. I prefer them to tapcons and plastic anchors in most cases.
The design is finally done and thanks for all the info.
We are going with 3/4 emt and 4x4 boxes everywhere.
Maybe you can help with box reccommendations and covers in particular.
No wiring devices bought yet.
We have both single and double outlets and switches, a few single GFCI's, some ceiling boxes needed and exterior light mounts and a couple of weatherproof duplexes.
Any help will be appreciated on selections.
Please do this and you'll have loads of good info.
Click on the left side tab "Box Covers and Conduit Bodies".
Now look in the lower right and right click on "Catalog" and download the .PDF file. Once done open it with Adobe Acrobat Reader and you're set. You'll need to work through the pages until you find the right covers. They are on pages C10 and C11 in the catalog.
Are you sure you really want to use 3/4 EMT? Normally 1/2 EMT is more than large enough. If you think you may want a 50 Amp receptacle for a welder or such, then I can see it. In that case you should look into 4-11/16 deep surface boxes too. For the normal stuff, I really can't see a need for 3/4 EMT. You can pull (4) #10 type THHN wires through 1/2 EMT just fine and I bet in many cases you'll only need (3) #12 wires.
As for the 4 x 4 boxes, I recommend looking at RACO #190, 191 and 192. A good electrical supply house should have one if not all of them in stock. Ask to see them before buying. There are some differences regarding knock-outs on them. The #185 is too shallow and ends up being a PITA product for most users.
Additionally I recommend downloading and printing out this part of the RACO catalog. It's another .PDF Adobe Acrobat file.
If anyone needs the FREE Acrobat Reader, you may download it here.
Please note that I've had problems with Firefox browser on the Hubbell-Raco web site and thus recommend using Internet Explorer which seems to work fine.
Those catalogs were very helpful.
Now we have 4x4 boxes (leaning towards the 2 and 1/8 deep).
1/2 emt; most we will have is 6 number 12's in one conduit.
This is a small addition; 2br 1 bath and a laundry; we are thinking of putting in a sub panel as the home runs will go 45 feet without it.
4-20A circuits; 1 for the wet areas; 2 for the br's and 1 for exterior and future.
Was wondering why ceiling boxes are octagonal.
Also what is the O.D of 1/2 emt.
Can you run 1/2 emt down the wall surface and into the top of the box without an offset coupling.
They call it 1/2" EMTube but the inside diameter is not 1/2". My old 1999 NEC book has an internal diameter of 0.622". Don't know what the outside diameter is.
Use THHN type wire like Woussko said it is thinner and has a hard covering for pulling in conduit. You also need to pull a ground.
If you can find a 1/2" bender it is easy to use to offset the EMT. Usually somebody has one lying around. The offset fittings are very costly at least where I live.
Unless it is a local code, he doesn't need to pull a ground if he is using solid runs of EMT. EMT is rated for grounding as long as you use the correct fittings, which is pretty much any commonly used fitting, pulling another ground would be redundant.
Also, you can just go from the wall into a fitting, but it will not look good or professional. Any local rental store or hardware store should have a 1/2 EMT bender for rent for cheap. Doing a 1/2" box offset is pretty simple.
The outside diameter of 1/2" EMT would be fairly close to 3/4" or 13/16".
The only reason I have ever come up for ceiling boxes being octogonal is because the mounting straps on most fixtures are too short to stretch across a 4x4 diagonally. An octogon has a shorter distance between the screw holes.
If you go over 6 conductors (not counting a ground) in a single conduit you have to derate your conductors to 70% of the 20 amps or 50% if you go over 10 in a single conduit. So keep your runs to 6, and you will only have to derate to the standard 80% which is what you have to do anyways.
Didn't know that, in Ontario we need a ground in EMT runs.
1/2 inch emt only in traffic areas; romex through the roof trusses to a JB then down the wall in emt at each of the boxes.