Rohn Foldover tower summary - by WB2DNE - November 1997 I received 11 responses to my inquiry about the use, maintanance and safety of Rohn foldover towers that I posted on this reflector last week. All but one were positive. The one negative response was associated with a situation when the winch cable broke during the foldover process. I'd like to thank all those who responded - if all goes well I may have a 64 foot Rohn 45G foldover next spring. 73, Ed WB2DNE ===================================== You wrote: >My questions; how easy/difficult is it to un-tension and detach the top set of guys prior to folding over - can it be a single person job? Yes it can be done by one person but a second person is helpful to keep the guys from tangling in something as the tower is lowered. >What type and how often does maintanance need to be done on the winch, cable, foldover section etc. My 45 has been up for 10 years with no maintenance required, just close inspection before use. >Are there any reports of disasters/failures during the foldover process? I've used and seen them used for over 30 years. The only failure seen was a 25 that was overloaded with antenna weight by a friend. Bent the hinge section that I repaired and still have in use. >How does the Rohn foldover concept compare with crank-ups? I have both. Both require that you treat them with a lot of respect. Remember, the foldover requires that you climb to the hinge point and remove the back bolts that hold the hinge section together before you can lower. ========================================================================== I am the happy owner of a 64 foot 25G tiltover and hope to put up a 45G next year also. Have had it up for about 8 years and it is great. Have had no trouble with the winch/cable etc. I just keep it oiled and painted and the cable once a year sprayed with cable lube. To tilt it over is a one man job for sure, I just loosen the turnbuckles on one side and crank it over. Work on the antenna upside down. Have a 6 el KLM long boom 15 meter beam (36 foot boom) and a T2X rotor, have had a 3 el ten or 3 el 6 meter stacked 6 foot higher at times. I have to really recommend one as I have had to quit climbing due to back problems. Great tower and price not too bad even. ========================================================================== I have been using a fold-over for the last 10 years. I inspect my tower every 6 months, good PM will keep you ahead of any problems as you start to see them. You only have to undo 2 top guys to tip the tower down. I tip my tower over in about 10 min's. I use a Loose gage to make sure all guy's are at the correct tension. Rohn over builds this tower. As long as you stay at or under the loads put out by Rohn it will last as long as any Rohn tower. I have a Force12 C4XL on top of mine. ========================================================================== On Wed, 5 Nov 1997 10:28:55 -0600 (CST) wb2dne@ix.netcom.com writes: >My >questions; how easy/difficult is it to un-tension and detach the top >set of guys prior >to folding over - can it be a single person job? My Rohn 25 48' foldover has been up for 20 years. To remove the top guys you just unscrew the turnbuckles until the top guys are loose and unscrew a bolt, or in my case with old-style Philly terminations, pull a cotter pin. It's a one person, 4 minute job. When the tower is folded over, the two bottom guys closest to the antenna also go slack and can be removed temporarily if they get in the way. > What type and how >often does >maintanance need to be done on the winch, cable, foldover section etc. I've never done any maintenance on the cable or foldover section. I had to disassemble the winch once and clean it up because the clutches were stuck. It was no big deal. The winch has a little manual with an exploded view of all the parts and how they fit together. Actually, I fold it over so seldom, I really should take the winch off and store it in the garage when it is not being used. Keep in mind that I live in a very dry desert. > Are there any >reports of disasters/failures during the foldover process? How does >the Rohn foldover >concept compare with crank-ups? I think it's safer than a crankup, but I would not overload it. The current Rohn catalog specifies a safe dead weight load at the apex. Old catalogs used to have an additional specification "safe moment about the hinge." As I remember that spec, it was approximately = (safe load at apex) x (distance from apex to hinge). In this case 190 x 16 = 4750 ft-lbs. You apparently have a long mast, so you need to go through the moment calculation for each component; rotor, mast, each antenna, coaxes, etc. to make sure you don't exceed 4750 ft-lbs. The foldover is not as cost effective as it used to be when priced against crankups. It's no fun installing the boom section, since it weighs 165 pounds. It has guy wires, which are unsightly, and always in the way when you're trying to do something. If I were to do it again today, and had $2200 to spend, I think I'd buy a heavy duty 55' crankup. Actually, I think I'd spend $4000 for an LM-470E 70-footer. Not many choices available when you don't like high work. Oh by the way, installing or removing a foldover requires high work. ========================================================================== Hey Ed, Had a 25G foldover years ago. Maintained it well. One day the aircraft cable supplied by Rohn broke. Near miss of possible fatality. I will NEVER have a foldover again. ========================================================================== Howdy --- I have 25G foldover up at this location abt 18 yrs and previously 5 yrs at another location. Only had 40ft up and no problems with tension or anything else. Mine has a 6el 6mtr, 16 el 2mtr horiz, 12 el 2mtr vert polar & 16 el 432 horiz on it. All yagis. One should ck the cable for rust every now and again --- guess I should change mine out some time. ========================================================================== ED; I used a 68 ft. 25G fold-over in the Canal Zone with a 2 el. 40m beam. One person loosens back upper guy; then pull pin, then start boom going at winch end. ALL on a calm day and no difficulty encountered. ========================================================================== I have used 25G and 45G foldover towers since 1962 and am satisfied with their performance. Currently I have two 45G foldovers installed. One has a KT-34XA and a M2 6M2WL installed and the other has four FO-25 432 antennas plus four 45 element loop yagis for 1296 installed. It is very easy to "un-tension" the back top guy wires with the turnbuckles and common sense maintenance on the winch is required. It is recommended you have at least one extra person to help you when you are tilting over the tower but it can and has been done alone. I use a "x-cross'" brace to support the top end of the tower when it is lowered and the antennas are being worked on. A heavy duty 12 ft or higher step ladder is a plus when working on the arrays. ========================================================================== Ed, I just put up a Rohn 45G 64' foldover last month. Bob W2CNS helped me. It works great. Quite easy to tilt over, very smooth, positive. Gave me a good secure feeling. Easy to get it off the dime to start the tilt. Didn't twinnnng upon landing back st raight up again. Excellent. I consider Bob, W2CNS the expert. I only have a small tribander on top of mine. Guess the dead load rating of 135 lbs is a limiting factor, especially if you feel the need to use steel mast material. Can increase that by limiting to 1 full section and the top section above the hing, 54 ft height. The reasons I selected the foldover over crank up models: relative small concrete base requirements (dug hole myself, mixed cement myself), tower is in sections - doesn't require heavy machinery to move and install (that you'd have to hire $$), about same price as US Towers HDX-555 but 10 ft. taller, the 4 point guy system is fairly small footprint, 25 ft square. Note also the 45G is *VERY* confortable to climb/install, more so than 25G. Bob and I together were on the tower all the way up during install. Lots of room to stand and work. ========================================================================== I missed the initial question so will give you my response. I have helped two guys with Rohn Fold overs with good success. One is a 25 fold over and the problem we had was the winch breaking with an extra section above and below the fold over point. The other is a 45 and they have the larger winch already installed on this one. This was three years ago and it supports a big Hy-Gain LP and a homebrew 2 el 40. We did guy it 4 feet from the top and just above the fold over section with phillystran every 120 degrees. The 25 has a 2 el quad on top for 20 to 10 with a single 40 loop. No problems with either....just be careful on folding over! They are fine towers. ==========================================================================