TECHNICAL GUIDE · COMPONENTSMay 29, 2026

About 1-1/2" NPT Pipe (1.5" Pipe) Used with TV & Projector Mounts

1-1/2" Schedule 40 pipe is the backbone of our TV and projector ceiling mounts. It is also called an extension column, mast, drop pipe, drop tube, or pole. Here is why we chose it, the exact dimensions, and how its tapered NPT threads work.

Also written as 1-1/2", 1 1/2", 1-1/2", 1.5 inch, or 1.5" NPT. All the same pipe.

Selling mounts online since 2003Expert mounting supportShips from Plano, TX

Why 1-1/2" Schedule 40 pipe?

It is not a proprietary part. It is the same rigid pipe stocked at every hardware store, which makes an entire ecosystem of couplers, extensions and fittings available to you.

Sourcing
Easy to find locally
The same rigid pipe used for electrical conduit and home plumbing, so replacement parts are everywhere.
Strength
Strong and rigid
A thick 0.145" wall gives excellent strength for hanging a TV or projector.
Material
Steel or aluminum
We now make most of our pipe from aluminum to cut shipping weight with minimal strength loss.
Ecosystem
Widely adaptable
The same pipe runs through scaffolding, lighting and stage truss, and handrails, so parts are easy to source.

Actual size and dimensions

A common surprise: 1-1/2" pipe does not measure 1.5" across. "1-1/2 inch" is the nominal (name) size. The pipe actually measures about 1.9" on the outside. If it is threaded, rigid, and holds a TV or projector, it is 1-1/2" NPT pipe.

Spec1-1/2" Schedule 40
Nominal size 1-1/2 inch (1.5")
Actual outer diameter (OD) 1.900" (about 1.9")
Wall thickness 0.145"
Inner diameter (ID) about 1.610"
Thread 1-1/2"-11.5 NPT (11.5 TPI)
Thread taper 3/4" per foot
Material / finish Steel or aluminum, black powder coat
"1-1/2 inch" is a nominal name, not the measured size.
1.900" OD 1.610" ID 0.145" wall
Cross-section: the nominal name is not the measured size

How do I know it's really 1-1/2 inch pipe?

Grab a tape measure and measure straight across the outside of the pipe at its widest point (the outer diameter). Most people eyeball 1-1/2" pipe as "about 2 inches," and that is right: 1-1/2" Schedule 40 pipe measures 1.900" on the outside, just under 2". Measure the bare pipe, not over a coupler or fitting, which will read larger. If it comes in right around 1.9", it is 1-1/2" NPT pipe, the size used on nearly every TV and projector mount we sell.

The one size to rule out is true 2" pipe, which a few older or heavy-duty mounts used. Genuine 2" Schedule 40 pipe measures 2.375" (about 2-3/8") on the outside, noticeably fatter than our pipe. So the quick test is simple: about 1.9" (a hair under 2") means 1-1/2" pipe; about 2-3/8" means true 2" pipe. The thread count is another tell, 1-1/2" NPT pipe has 11.5 threads per inch.

About the tapered (NPT) threads

A common question is why the pipes do not thread all the way in. That is by design. These are NPT (National Pipe Thread) tapered threads that get tighter the further they screw together. In plumbing the taper seals against leaks. For mounting TVs the benefit is thread-locking: the tighter they are screwed, the harder they are to loosen. Pipes usually thread together 3 to 4 turns and then stop. That is correct, not a defect.

11AC001 coupler · 2.559" 0.94" thread 1.900" OD pipe 2.165" OD 0.345" engaged · 3-4 threads DETAIL: 60° V THREADS MESH 60° P Threads mesh · 60° V form Pitch 0.087" · 11.5 TPI pipe crest fills the coupler valley
1-1/2"-11.5 NPT · 60° V thread form · 11.5 threads per inch

Building the exact drop you need

Every 1-1/2" NPT pipe here uses the same thread, so pieces mix and match. To add length, join two pipes with a threaded coupler, which itself adds about 1.5" to the total drop. The 10", 20", and 30" extension kits already include a coupler. For an exact height, a telescoping extension dials in the drop within a range. The 1-1/2" pipes can also replace the pipe or mast that came with your mount.

Most major AV mount brands build their extension columns on the same 1-1/2" NPT standard, so our pipe, couplers, ceiling plates and mount heads are interchangeable with those systems.

Common questions

Q

Is 1-1/2" NPT the same as 1.5 inch pipe, and why does it measure almost 2 inches?

Yes. "1-1/2 inch" is the nominal name, not the measurement. Schedule 40 1-1/2" pipe actually measures 1.900" (about 1.9") on the outside. If it is threaded and rigid, it is 1-1/2" NPT.

Q

How many turns should the pipe thread in?

About 3 to 4 turns by hand, then it snugs up and stops. That is the tapered thread doing its job, not a defect.

Q

Will this pipe fit my Chief, Peerless-AV, or Premier Mounts column?

In most cases yes. Those brands build their extension columns on the same 1-1/2" NPT standard, so our pipe is interchangeable. See our cross-reference to match a specific part number.

Q

Steel or aluminum: which should I choose?

Both handle the job. We use aluminum on most lengths to cut shipping weight with minimal strength loss. Steel is used where a specific part calls for it.

Q

How do I join two pipes to get more drop?

Use a 1-1/2" NPT threaded coupler. It screws the two pipes together and adds about 1.5" to the total drop. The 10", 20", and 30" extension kits already include one.

Q

Can I use pipe from a hardware store?

Standard 1-1/2" Schedule 40 pipe is the same base stock, so it will thread. Ours is cut to mount-friendly lengths, deburred, powder-coated black, and offered in lighter aluminum, so it looks right and ships cheaper for TV and projector use.

Building a pipe-mount setup?

Get the right pipe, cut to length, plus the parts to finish the job.

References: Nominal Pipe Size, National Pipe Thread (NPT), ASME B1.20.1 taper pipe threads.