mast idea

[BOOTY MONSTER]

ive been thinking about using either 1 1/2 inch or 2 inch conduit for mast material . not the super heavy stuff with the threaded ends and collars , but the regular stuff . what i was thinking of was taking them to a muffler shop to have the ends either reduced or expanded so the next section either slides in or over the previous section ..... like typical 5 and 10 ft 1 1/4 inch diameter mast sections sold at the phone shack .

RadioShack.com

im thinking the larger diameter conduit should be stronger , especially the 2 inch .
im thinking neck it down to size 12 inches and put them together using a #5 hardened bolt/washers/nuts about 5/16 or 3/8 diameter for locking pins.

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what do you think ?

 

[mackmobile43]

Mine is made out of the top pipe from a 5' chain link fence which in 1 1/2'' diameter and bolted to the over hang of my roof with 10' above the roof line and has been up there for 4+ years.

These sections are 21' and one end is already reduced like you're describing and if you like you could cross drill to add guy cables.

 

[office888]

I used that stuff. EMT, not rigid.

1.25" slipped into 1.5". Hole drilled through both, bolt+washer+lockwasher+nut.

Works great for guyed applications.

I'd use the rigid stuff for unguyed.

 

[BOOTY MONSTER]

they sell a similar fence top rail here , but its 1 3/8 inch diameter and comes in 10 ft 6 inch sections . i held a piece in the middle and shook it and could wobble it a little . the 1 1/2 and 2 inch conduit doesn't seem to budge at all .

 

[HomerBB]

Give it a whirl.

I've used the top rail, too, and it bent over without guys. The tubing you're looking at may just be the trick.

Where are you going to mount it?

 

[mackmobile43]

they sell a similar fence top rail here , but its 1 3/8 inch diameter and comes in 10 ft 6 inch sections . i held a piece in the middle and shook it and could wobble it a little . the 1 1/2 and 2 inch conduit doesn't seem to budge at all .

Yeah this stuff I have is industrial grade.

 

[74IN]

I use the top rail as well, it comes in 10'6" and 21' sections.

Works great, the 21' stuff is best, just gotta sort through it to get a really straight piece.

 

[mackmobile43]

I use the top rail as well, it comes in 10'6" and 21' sections.

Works great, the 21' stuff is best, just gotta sort through it to get a really straight piece.

Yeah I had my pick of several thousand.

 

[HBW1412]

Use Structural Steel

I used structural tubing to make my mast. Tubing is different from pipe or conduit. Tubing is the stuff used to make the cages in race cars. It's much stronger and it comes in 21' lengths. I have an I-10K on top of 2 sections welded together with the joint reinforced with 1/2" x 1" flat bar stock that overlaps the butt joint weld by 2 ft. on each side in three seperate locations. The bottom of the mast is mounted about 3' high in a "sleeve" that is mounted in a 6" steel pipe filled with concrete that is buried in the ground 4 feet. I have NO guy wires and I'm almost at the 60' legal limit for cb antennas.

Now, the tubing is steel and has to be painted. I used a military grade aircraft paint. I got it from a military surplus store. It is olive drab in color, but I don't mind because it's the only paint I could find that I felt would hold up well for long periods of time.

This antenna has been up for over a year with absolutely no problem. It has seen high winds and the structural tubing held up with no damage. I ordered my tubing from metalsdepot.com and had it delivered by Fedex. The shipping was VERY reasonable, but I think you can get structural tubing from most welding shops.

With the tubing, shipping, concrete and paint I have around $400.00 in this mast. I really like it because I don't have any guy wires. (I hate guy wires)

One warning - When I set the mast upright for the first time I didn't have the bottom scotched well. I had the antenna end held up by a makeshift "sawhorse" that was high enough to keep the radials off the ground. As I began walking the antenna upright the bottom began to slide and I hurt my back a little to save the antenna from getting damaged. What I do now is scotch the bottom with cinderblocks and rebar. Once you have walked the antenna into an upright position the entire mast with antenna and coax (please use at least LMR-400) is light enough to be lifted into the sleeve that's mounted in the 6" steel pipe.

Anyway, this is my first post on this site, so I hope someone finds this idea helpful.

 

[mackmobile43]

Some good suggestions.

 

[W5LZ]

Things can rust from the inside -> out. Did you paint the inside of that tubing??
- 'Doc

 

[HBW1412]

Things can rust from the inside -> out. Did you paint the inside of that tubing??
- 'Doc

No, I didn't paint the inside. I did weld caps on both ends to keep water out. Once a thin layer of rust forms on the inside the rusting process should slow down so significantly that the tubing would never rust enough to cause any concern within my lifetime.

You can purchase this same tubing that has been dipped in an anti-rust coating which would quell all concern about rust on the inside, but the extra cost wasn't worth it to me.

 

[office888]

I used structural tubing to make my mast. Tubing is different from pipe or conduit. Tubing is the stuff used to make the cages in race cars. It's much stronger and it comes in 21' lengths. I have an I-10K on top of 2 sections welded together with the joint reinforced with 1/2" x 1" flat bar stock that overlaps the butt joint weld by 2 ft. on each side in three seperate locations. The bottom of the mast is mounted about 3' high in a "sleeve" that is mounted in a 6" steel pipe filled with concrete that is buried in the ground 4 feet. I have NO guy wires and I'm almost at the 60' legal limit for cb antennas.

Now, the tubing is steel and has to be painted. I used a military grade aircraft paint. I got it from a military surplus store. It is olive drab in color, but I don't mind because it's the only paint I could find that I felt would hold up well for long periods of time.

This antenna has been up for over a year with absolutely no problem. It has seen high winds and the structural tubing held up with no damage. I ordered my tubing from metalsdepot.com and had it delivered by Fedex. The shipping was VERY reasonable, but I think you can get structural tubing from most welding shops.

With the tubing, shipping, concrete and paint I have around $400.00 in this mast. I really like it because I don't have any guy wires. (I hate guy wires)

One warning - When I set the mast upright for the first time I didn't have the bottom scotched well. I had the antenna end held up by a makeshift "sawhorse" that was high enough to keep the radials off the ground. As I began walking the antenna upright the bottom began to slide and I hurt my back a little to save the antenna from getting damaged. What I do now is scotch the bottom with cinderblocks and rebar. Once you have walked the antenna into an upright position the entire mast with antenna and coax (please use at least LMR-400) is light enough to be lifted into the sleeve that's mounted in the 6" steel pipe.

Anyway, this is my first post on this site, so I hope someone finds this idea helpful.

Oh man, I've got some DOM tubing.

I'd hate to use that for a mast. It's heavy, and EXPPPEENNSSIIVVE.

 

[HBW1412]

DOM Tubing (Drawn Over Mandrel)

I just checked the metalsdepot.com site to see the pricing of DOM tubing and you are right, it is expensive. Significantly more expensive than what I paid for mine a couple of years ago.

The tubing I used has 1/4" wall thickness. I did use 2" tubing which does add some weight, but I am still able to handle it by myself. I did hurt my back trying to raise it, but I contribute that to not having the bottom scotched well. Once I had the bottom scotched I was able to hoist it with no help, but I'm a big guy in decent shape. I have a few back problems anyway from shoeing horses, but I still think the tubing is the way to go. It makes for a very strong mask.

If I didn't despise guy wires so much I would probably use pipe or conduit, but guy wires are not an option for me. Besides not liking how they look I am concerned with my horses running into them if they get out of their fence.

Granted, you will pay more for this type of tubing, but it has several advantages that guyed pipe simply can't offer.

P.S.: I trim a lot of donkeys so I know how the person feels that made this emoticon. I think it's funny... :bdh: - BAD Donkey!!! BAD!!! LOL