Channel Master 40ft Mast CM-1850

[Captain Midnight]

I have one of these telescoping masts coming and am trying to find out some information to plan my installation. I have a mast bracket at the end of my roof peak at 21ft. I ordered the 40ft mast but only plan to use about 32ft of it tops. I plan to guy it 3 ways at 30ft and have the antenna with rotor just above that.

Anyone know if there are predrilled holes for leaving sections not fully extended? I figure leaving some sections overlapped more could help the stability too.

 

[Jim5506]

Predrilled holes are only near the bottom of each section (about 4 inches up) plus a notch on each side at the bottom for you to extend the mast to full height and drop the section into a bolt or pin through the section below. They do include a "J" bolt that can tighten anywhere on the mast to hold it there but that usually collapses the section a bit and makes further extension and adjustment problematic.

If you have a 4 section mast, why not just use the three top sections (~32 ft.) and store the bottom section for later. I would recommend guying the top of every section that is above the mounting point, you do not want high winds to snap a guy wire and destroy the entire setup.

Partially extending a section will introduce some wobble into the mast because the bottom is slightly flaired to fit inside the stop of the section below and so you cannot pull an upper section out of the top of the section below. This makes for a snugger fit as you raise the section.

It gets slightly smaller until the final crimp near the top of each section.

 

[Captain Midnight]

Thanks for the info. I will try that method

Predrilled holes are only near the bottom of each section (about 4 inches up) plus a notch on each side at the bottom for you to extend the mast to full height and drop the section into a bolt or pin through the section below. They do include a "J" bolt that can tighten anywhere on the mast to hold it there but that usually collapses the section a bit and makes further extension and adjustment problematic.

If you have a 4 section mast, why not just use the three top sections (~32 ft.) and store the bottom section for later. I would recommend guying the top of every section that is above the mounting point, you do not want high winds to snap a guy wire and destroy the entire setup.

Partially extending a section will introduce some wobble into the mast because the bottom is slightly flaired to fit inside the stop of the section below and so you cannot pull an upper section out of the top of the section below. This makes for a snugger fit as you raise the section.

It gets slightly smaller until the final crimp near the top of each section.

 

[primestar31]

I would recommend guying the top of every section that is above the mounting point, you do not want high winds to snap a guy wire and destroy the entire setup.

Captain Midnight This is TRUE! Every 10ft (top of section) above a house or eve mount bracket, MUST be guyed with at least 3 guy wires around it.

 

[Captain Midnight]

Captain Midnight This is TRUE! Every 10ft (top of section) above a house or eve mount bracket, MUST be guyed with at least 3 guy wires around it.

I am planning a guy set at 30ft. Roof peak is a little over 20ft. 32ft extension total.

 

[primestar31]

Roof peak is a little over 20ft.

So, there'll be an eves bracket around 20ft? If so, then guys just at the top should be fine.

 

[Jim5506]

So, You are mounting the pole at ground level beside the peak of your house?

 

[Captain Midnight]

So, You are mounting the pole at ground level beside the peak of your house?

Yes and a bracket on the eave and middle of the wall. Guys set 10ft above top bracket. Base of the pole is buried 12".

 

[primestar31]

Base of the pole is buried 12"

Is that just going to be just in dirt, or is there some cement involved? I highly recommend at least one 80lb bag of Quikrete. You should be a little concerned with wind load, even with tv antennas.

 

[Jim5506]

What provision have you made to prevent the tower from rotating?

I have an old roof top antenna mount that I've surrounded by 4 cinder blocks. The first photo is of the base with one cinder block removed, the second the tower and Channel Master 4228 on top. Attached to the peak with a joist hanger spread out and attached with screws to the facia.

Just above the base is a 2 ft long piece of drive shaft.

The mast is inserted inside the drive shaft, ancored by a long enough carriage bolt.

 

[primestar31]

Jim5506 You need a drip loop where that coax goes into the bottom of that eve vent. Without it, I can almost guarantee you that you may have a lot of ROT there.

Rainwater will run down the coax, and right into that joint. IF you put a drip-loop right there (like an elbow) the rainwater will drip off the middle-bottom of that drip-loop, before it can run into/wick into the wood wall.

You just can't be too careful when it comes to water infiltration into a wall or roof.

What Is A Drip Loop and Why You Need It · My Busy Retired Life

What is a drip loop? Without them your home could be facing extreme water damage in the future. Find out what they are and bring yourself peace of mind.

www.mybusyretiredlife.com

 

[Captain Midnight]

Is that just going to be just in dirt, or is there some cement involved? I highly recommend at least one 80lb bag of Quikrete. You should be a little concerned with wind load, even with tv antennas.

I am thinking it will be needed. I had my first storm front pass by over it and the 3 guys saved my butt. But my wind anemometer only registered a gust of 28mph. I definitely plan to concrete the base and switch to a 4 guy system for safe measure. The wind load is definitely higher with it up at 32-33ft.

 

[Captain Midnight]

I think it looks pretty good. Hopefully the neighbors can handle it... someone reported my '89 Ford Van to code enforcement as a "non operational vehicle" Code officer came by and asked if it ran. I had driven it the day before... so I started it up and he tore up the ticket.

 

[Jim5506]

Does the rotator have guy wire attachments, if so, I would have guyed to it.

Lots of weight and wind resistance above the top guy point.