The more I read with regards to this topic, the more sense it makes to use a
crane.
I had a crane dude that was $100 per hour and it made the assembly of my system
so easy that the project was finished in a day which was beyond the
expectations of the tower dude.
The stresses were minimal and there was no jockeying of guy wires or other bits
of potential headaches.
Time is money and anytime you can reduce headaches is money well spent and
likely a savings.
Nat
> On Sep 14, 2019, at 2:53 PM, <wc1m73@gmail.com> <wc1m73@gmail.com> wrote:
>
> I'm not an expert, but I did tram three 4-el SteppIRs, mounted on TIC rings,
> and a Cal-Av 2D-40A, mounted on the bottom of the mast, up my 110' Rohn 55
> tower using a similar system. The SteppIRs are only 110 lbs or so with 30'
> booms, but they're not very well balanced due to the heavy motors mounted on
> the booms. The Cal-Av is 165 lbs on a 16' boom with 75' elements. Your
> antenna and tower are considerably larger than mine and may require different
> materials and procedures.
>
> All tower work is dangerous, including tramming. My advice is to give a lot
> of thought to how you will setup the tram and perform every step of the
> process, especially what moves will be required on the tower. Here's what I
> did:
>
> 1. I used a split "trolley" on the tram wire, which consists of two pulley
> wheels mounted so that you can slide the sheaves apart to slip the trolley on
> the wire. A carabiner attaches to the bottom of the trolley and the
> attachment point on the boom. As I recall, I used heavy-duty nylon straps on
> the boom to attach the carabiner, and secured the strap with hose clamps to
> keep it from sliding on the boom. I used some sort of padding between the
> hose clamps and strap to prevent the edges of the hose clamp from digging
> into the straps. There may be a better way to attach the tram point on the
> boom. Maybe some pros can chime in.
>
> 2. I found that it's essential to use a "rudder" attached to the boom. The
> hoist rope is attached to the rudder, not the boom. The rudder keeps the
> antenna at the angle of the tram wire, so you don't need to attach ropes to
> the elements for the ground crew to keep the antenna at the correct angle. I
> fabricated my rudder out of a piece of thick aluminum angle stock about 1.5-2
> feet long. It's attached to the center of the boom with a U-bolt. The hoist
> rope is attached to the other end of the rudder with a carabiner through a
> hole.
>
> 3. However, you may still need ropes thrown over the ends of the boom (not
> tied!) to keep the antenna from tilting perpendicular to the tram line.
> Depends on how well the antenna is balanced. My recollection is that I didn't
> need the ropes. That could have been partly due to using the rudder. You
> should be able to get a pretty good idea of whether ropes will be needed
> while the antenna is still close to the ground as you begin hoisting. Usually
> minor adjustment of the boom mount point will balance the antenna.
>
> 4. My anchor point is closer to the tower, I don’t recall offhand where I put
> it, but I think it's roughly 200' away. The highest tram point was 110'. This
> was fine for getting the antennas over the guys, but to get them over the
> highest mounted antenna I had to rotate the TIC ring so the mounted antenna's
> boom was perpendicular to the tram, then rotate the boom in its boom-to-mast
> clamp to point the elements on the tram side downward and away from the tram
> line.
>
> 5. I used a 3' screw-in anchor from an AB-577 surplus military mast. I was
> only able to get about two feet of it in the ground until it hit ledge. While
> this worked, I probably shouldn't have relied on that anchor. When we trammed
> the Cal-Av, vibration on the tram line caused the anchor to oscillate
> slightly and I could hear the tip of it banging against the ledge. Luckily,
> it held. I have to believe that a reasonably heavy pickup truck or larger
> truck could handle the weight, would be safer than a screw-in anchor or a
> tree (depending on the tree), and has the advantage of being able to adjust
> the anchor point to get the best angle for the tram line.
>
> 6. I didn't add a temporary guy opposite the tram line. The tram line was
> secured to the tower, not the mast, directly opposite one of the tower legs,
> the main guys are 1/4" Philly and EHS, and the anchor piers are one size
> larger than required -- 6'x3'x1.5', plus quite a bit of extra concrete to
> fill the irregular hole. It seemed to me that adding another temporary guy to
> the main guys wouldn't increase the margin of safety. I would definitely have
> done it had the tram line been attached to the mast.
>
> 7. I used a come-along at the anchor rod to lift and tension the tram line. A
> vehicle could have been used instead, though I'd still use a come-along for
> fine adjustment and to avoid an unfortunate accident. The tram line was
> attached to the come-along with a Klein grip so I could adjust the length of
> the tram line for each of the four tram attachment points for the antennas at
> 33', 66', 95' and 110'. A come-along cable isn't long enough to provide that
> much adjustment.
>
> 8. The tram line was secured to the tower using two heavy duty nylon rigging
> straps around each leg just above a cross member and a carbiner through the
> two free loops.
>
> 9. A pulley for the hoist rope was secured to the tower just below the tram
> line using similar strapping.
>
> 10. I used a My-Te 300AB electric (AC) capstan winch bolted to the base of
> the tower for the hoist rope. It's rated for 800 lb. single line. Same winch
> I used to hoist all the Rohn 55 sections, TIC rings, and other heavy items.
>
> 11. As your tower is 132' and you are mounting the antenna at 123', you can
> secure the tram line above the mount point. If you use a rudder, there will
> be a gap between the highest point the boom can reach and the mount point on
> the tower or mast. You will need a come-along mounted above the tram line to
> support and take the weight of the antenna off the tram line so you can
> remove it from the tram line, remove the rudder from the boom and lower the
> antenna to the mount point.
>
> (FWIW, I didn't want to secure the tram line for the Cal-Av to the mast,
> which is aluminum with a 1/4" wall, so I secured it to the top of the top
> section and secured the come-along to the mast. After supporting the antenna
> with the come-along, I disconnected the antenna from the tram, the ground man
> slacked the tram line, I relocated the tram line below the boom, and hoisted
> the antenna up and over the top plate to the mount point at the bottom of the
> mast. Pretty tricky for one person with a 165 lb antenna -- had to stand on
> the top plate for part of it. But none of that is applicable to your case.)
>
> Hope this is helpful.
>
> 73, Dick WC1M
>
> -----Original Message-----
> From: Charles Morrison <junkcmp@gmail.com>
> Sent: Saturday, September 14, 2019 10:03 AM
> To: TOWERTALK@contesting. com <towertalk@contesting.com>
> Subject: [TowerTalk] Can you TRAM this ?
>
> Will this work using a TRAM system and not a crane ?
>
> Antenna to raise: 310 lbs x 48ft boom to be installed at 123'
> Tower: 132' 55G (130MPH guying) with starguy at 122'
> Tram wire: 1/4" EHS
> Pulley on tram wire
> Tram anchor point: at ground level @ 300ft away from target tower.
> Slope: 0.41
> Antenna launch point 135 feet away from target tower. (h=0) (165 ft from Tram
> anchor point) Attach 1/2" rope to TRAM WIRE PULLEY - up to pulley @ 130ft -
> then down to electric rope capstan.
> Begin tightening tram wire to slope thereby raising antenna located 165 ft
> from target tower off the ground.
>
> Then begin tramming antenna with electric rope capstan.
>
> What weight/mass do I need at the tram anchor point ?
> Tree ?
> Vehicle ?
> Deadman anchor in ground ?
>
> Antenna launch point can not be moved. Lot is too narrow and theres another
> tower nearby.
>
> As an alternative, I may a usable tram anchor point 400+ feet away. - I'm
> going out to look ant how that lines up now ....
>
> -Charlie N1RR
>
>
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>
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