Gents,
I see an option to the pinning question. "SANDPAPER". The gripping power of
this
inexpensive and easily installed option will give good results. Use a large
grit
sandpaper and snug the clamps down. To provide traction glue two pieces of
sandpaper back to back with a waterproof glue i.e., contact cement or hot melt
blue. It will work as an alternative.
73 de n8csp k
jack colson wrote:
> Summary of: "To pin or not to pin"
> -------------------------------------
> What's the weight and turning radius of your proposed antenna? The
> G-800 is a pretty medium duty rotator and 14+ sq.ft. may exceed its
> capacity.
>
> In answer to your question, I don't recommend pinning the mast.
> First of
> all, drilling your 4130 will be a pretty tough job. That's the first
> reason
> NOT to do it.
>
> Second is that when you take a big gust of wind, not having the
> mast
> pinned will allow the mast to rotate slightly. If it's pinned, what you
> find
> out is what the next weak link in the system is - and it's usually the
> gear
> train. It's much easier and cheaper to recalibrate the antennas
> occasionally
> than it is to swap and repair rotators.
>
> As you're probably aware, the Yaesu mast clamps will crack at the
> slightest provocation. Be sure to follow their instructions.
>
> Cheers, Steve K7LXC
> --------------------------------------------------------------------
>
> But, Steve, Yaesu's instructions are very explicit in telling us to pin
> with
> the bolt provided! When I, as a believer in non-pinning, called Yaesu's
> tech
> support, I was told I must pin. Actually, considering that the 800SD(X)
> has
> no brake, this might be the proper thing to do. We can either crank the
> hell
> out of the clamps with no pin, and risk cracking them, or snug-em up
> gently
> per Yaesu's directions and pin. Wind blown rotation in the case of these
>
> rotators will just change its azimuth since there's no brake ("braking
> torque" is a result of gear-reduction and friction). With no brake,
> there
> should be less risk of gear failure. So...I pinned. When the wind blows
> it
> around, I just turn it back where it belongs. Just trying to follow the
> 'Prime Directive' ;>).
>
> Chuck, N4NM
> --------------------------------------------------------------------
> The antenna will tend to turn in the clamps otherwise, and if you
> tighten
> them enough to hold without the pin, they tend to break. Yaesu USA told
> me
> that they tried to get the factory to change to steel, but without
> avail.
>
> On mine (-1000SDX), I went with a pin, but I purposely used one that is
> smaller than the standard. My theory is that in a really extreme
> situation
> the pin might shear before the rotor died. So far I haven't had to find
> out!
>
> There have also been threads on Towertalk about materials that can be
> used
> between the clamp and mast to increase friction. The one I liked best
> was
> high-friction industrial belting scraps -- you might check the archive.
>
> 73, Pete Smith N4ZR
> n4zr@contesting.com
>
> -----------------------------------------------------------------------------
>
> Jack,
> I would pin it for sure. My experience is that when a pin I had broke,
> the antenna just spun within the clam shells of the SDX 1000. In fact,
> I
> had two pins from Yaesu break, so I replaced theirs with a stainless
> steel
> pin and have not had any trouble. The clam shell clamp will not hold
> your
> antenna, it is not strong enough, you need the pin.
> 73, Bruce K1XR
>
> ------------------------------------------------------------------------------
>
> Okay, okay - I'll concede the point.
>
> The original poster asked about *his* situation. I stand by my
> advice to
> 'not pin' since he's dealing with 4130 which will be a bear to drill.
> It's
> more of a practical consideration to me. I guess with the Yaesu
> 'prone-to-break' clamps, they're just ensuring that the mast won't slip
> inside the clamps.
>
> Cheers, Steve K7LXC
> --------------------------------------------------------------------------------
>
> Hi all,
>
> I use Yaesu rotors and big KLM antennas, and have tried it both ways.
> Obviously, there is no way to keep the KLMs from turning in the puny
> Yaesu
> clamps, so I've opted to pin. However, if you use Yaesu's supplied pin,
> it
> will simply shear off on both ends at the first gust of wind, so you
> MUST
> use SS bolts.
>
> Yes, the 4130 was a bear to drill through, but if you start with brand
> new
> titanium-tipped bits and go from smaller to larger while using some
> lubrication (and you exercise some patience, as well), you'll eventually
> get
> through. And I never have to re-orient the antennas (KT-34XA & 40M4 on
> same
> mast) anymore. They used to spin like tops!
>
> 73 de Jeff K2KV
> k2kv@reallybig.com
> ------------------------------------------------------------------------------
>
> From:
> "Barry Kutner" <w2up@mindspring.com>
> To:
> towertalk@contesting.com
>
> I also pin the mast which holds a TH7 and Cushcraft 402CD turned
> by a T2X. Been up there almost 10 years. A few years ago, while
> up on the tower, I noted the bolt was cracked in half! I forget the
> exact alloy, but it was a high strength steel with some Beryllium in
> it. I did replace it with another bolt, and so far, it's still in one
> piece,
> last I checked.
>
> Regarding drilling, I first tried with a standard bit - wouldn't dent
> the
> stuff. Then, bought a Cobalt tipped bit labelled "for hardened metals
> including stainless steel." With some cutting oil, went thru like
> butter.
> 73 Barry
>
> -------------------------------------------------------------------------------
>
> You guys have me worried mentioning how hard it is to
> drill 4130. Just put a 20 foot stick of 4130 1/4inch wall
> in my tower. I drilled 2 holes 3/8 diameter through it to
> pin it to a prop pitch to mast coupler with grade 8 bolts.
> Had no trouble drilling it with standard drill bits and a
> battery powered Makita drill. Took a little pressure, and
> started it with 1/4 bit then drilled it out to 3/8.. yes I
> checked the mast, it was stamped with a mil spec number
> and 4130 printed all along the length. Sure hope its real
> stuff when the wind and ice hit it this winter. Have another
> piece here of 13/4 4130 that I cut with a hacksaw, didnt
> seem that hard either. Or do I have good blades?
> 73 Merv K9FD
>
> -----------------------------------------------------------------
>
> Greetings:
>
> It is not advisable to pin the mast to the rotor. In fact, many
> manufacturers of rotors tell you that if you do pin the mast
> in the rotor, you'll void their warranty.
>
> If you feel you need the additional "security," then a better idea
> is to pin the antenna's to the mast and leave the mast free in
> the rotor. This way, if it does spin under a load, it is easier to spin
>
> the mast back to where it should be than to spin an individual antenna
> somewhere up the mast.
>
> I never pin both the antennas and the mast...if you do and a big
> blow comes along, you have practically guaranteed that *something*
> will break.
>
> 73, J.P. W2XX
> -------------------------------------------------------------------
> From:
> Dick Flanagan <dick@libelle.com>
> To:
> Tower-Talk Reflector <towertalk@contesting.com>
>
> >In a message dated 99-09-06 17:49:54 EDT, clewis@ro.com writes:
> >
> >> But, Steve, Yaesu's instructions are very explicit in telling us to
> pin with
> >> the bolt provided!
> [...]
> > Okay, okay - I'll concede the point.
> >
> > The original poster asked about *his* situation. I stand by my
> advice to
> >'not pin' since he's dealing with 4130 which will be a bear to drill.
> It's
> >more of a practical consideration to me. I guess with the Yaesu
> >'prone-to-break' clamps, they're just ensuring that the mast won't slip
>
> >inside the clamps.
>
> Just as another data point, M2 specifically directs you NOT to pin the
> mast to their Orion 2800 rotors. If you do, it will void your warranty.
>
> Actually, I'm glad they said that because I didn't want to try to drill
> my 4130 anyway! :)
>
> 73, Dick
>
> --
> Dick Flanagan W6OLD
>
> -------------------------------------------------------------------------------
>
> I did not have any trouble drilling 4130 mast either
> Tony
> N2TK
> -------------------------------------------------------------------
> From:
> "Dan 'Hank' Arney" <kn6di@groupone.net>
>
> For the life of me I do not understand what the big deal is of drilling
> 4130. If you use a SHARP drill, correct SPEED, exert a fair amount of
> PRESSURE and some lubricant it is like a hot knife going through butter.
>
> If you are doing it all correct you should get nice little spirals as
> the drill eats up the 4130, if you are getting chips then you are doing
> all of the above WRONG
> You can double drill it if like 3/8 or 1/2" with a 3/16 or 1/4"
>
> With the correct flute angles you can drill SS and plastics just as
> well.
>
> My .02 centavos
>
> Hank
> -----------------------------------------------------------------------------
>
> Thanks Hank for the info, thought it was just me going senile,
> I use quality drill bits from a machine shop and they go through
> very easy. Speed is very important depending on drill size..
> Maybe the ones having trouble use wallmart bits and run the
> drill at 5000 rpm ? 73 Merv k9FD
> -------------------------------------------------------------------------------
>
> Several years ago, when I first got my G-1000SDX, I asked Yaesu USA
> about
> the mast clamps/pinning issue. I was told at the time that they had
> asked
> the factory to change over to a more durable clamp design, and the
> factory's response was to add the bosses and drilling for the pinning
> bolt,
> while sticking with the old material. Presumably the new production
> clamps
> are as weak as the old ones, because the tightening instructions haven't
>
> changed.
>
> By the way, my G-1000 does have a brake -- a tiny drum, so identified on
>
> the blow-up drawing of the rotator itself. Also has a spec for braking
> torque, so maybe it's different from the G-800 in this respect, though
> the
> control boxes are identical.
>
> 73, Pete N4ZR
> --------------------------------------------------------------------------
>
> For whatever anecdotes are worth, I'm turning a Force 12 C-3/Short 40
> combination with a pinned G-1000SDX, and have not had any signs of
> trouble
> in 3+ years, including some pretty fierce winds. Since the Yaesu design
> is
> not a worm gear drive, and the brake drum is a very small device without
>
> the wedging design of the T2X-style, my hunch is that in a real pinch
> the
> brake drum will simply slip, at least until things hit the stop at one
> end
> or the other of rotation. Maybe they assume that in most cases the
> antenna
> will windmill into equilibrium before that occurs.
>
> 73, Pete N4ZR
> -----------------------------------------------------------------------------
>
> Hello Jack,
> As reported in prior posts, having some weight on the rotator is a good
> thing, as they are designed for a vertical load, which helps keep their
> bearings seated and wearing evenly. This also seems to help them resist
> lateral loads from wind, which try to push the mast back-and-forth down
> at
> the rotator level. Just be sure you are not over-loading the rotator
> weight-wise.
> What I did was to install a second thrust bearing above the rotator.
> During normal operation, I have the clamping bolts tight on the upper
> thrust
> bearing and loose on the lower bearing, with all the weight being taken
> by
> the rotator (I also have a Yaesu 800 SDX). For maintenance, I lift the
> mast
> and antenna assembly up just enough to clear the rotator, and tighten
> the
> clamp bolts on both bearings to hold it in place. Then I can remove the
> rotator.
>
> --...MARK_N1LO...--
> ------------------------------------------------------------------------------
>
> I do not believe you can make a blanket statement like that.
> I do not buy for one minute that pressure on the rotor is needed
> for sealing, or any reason. The use of two thrust bearings is ideal,
> as this removes ALL weight and keeps the mast centered in high
> winds.
>
> IMHO, the less work a rotor is required to do, the longer it will last.
>
> (((73)))
> Phil, K5PC
> ---------------------------------------------------------------------------
>
> From: Tom Champlin <w0hh@grapevine.net>
> To: <towertalk@contesting.com>
> Sent: Monday, September 06, 1999 7:57 PM
> Subject: [TowerTalk] To Pin!
>
> >
> > I have always pinned with my Yaesu G2800SDX. The clamshells show no
> > signs of wear or cracking. I have done this with my 20M4 (114lbs). and
>
> ^^^^^
> This (wear) is the key reason for pinning -
> IMHO.
>
> Any one who has had a knurled nut slip in a tool the first time and get
> stripped knows how
> much harder it is to get any purhcase on it the second time. The inside
> of
> the clamps have
> "teeth", made of cast aluminum that provide the gripping capacity. Spin
> the
> mast around
> a few times and they begin to lose their grip. From then on it is a
> vicious
> cycle of tightening
> and slipping to the point where the clamp breaks.
>
> Solution pin it and let the rotor (brakeless Yaesu 800 that I have)
> give.
>
> The manufacturers' suggestion.
>
> Regards,
> Rajiv, N2RD
>
> -----------------------------------------------------------------------------
>
> Thanks, W3TMZ
>
> --
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