Question & Observations

Question 1: After years of handhelds, I am about to install a
fixed mount GPS on a swing arm which will allow it to live in the aft
corner of the cabin and be viewable in the companionway. Prior to putting
holes in my boat, I’m wondering where you all have mounted the external
antenna. I’m thinking about the aft side of the boom gallows… the
boomkin would be good but, with a windvane, there is already too much junk
there. Any advice will be appreciated .

Question 2: Has anyone plumbed a LaVac with a straight shot to
the top of the holding tank? Naturally, I am keeping the vented loop for
over-boarding at the seacock but am trying to figure a way to increase the
“useful flushes” into the holding tank. I cannot overboard in the Great
Lakes and I figure I am using an extra quart or two per flush to move used
pizza to the holding tank via the vented loop. The input into my holding
tank is almost on the centerline. I’m trying to imagine a full tank/major
heel situation that might set up a siphoning situation. Anyone try this?
With the luxury?? of de-rigging each fall, I have discovered that
the finish on my sprit chafes through slightly on the underside at the aft
end of the gammon iron. Can’t think of a way to mis-tension the stays to
cause this so I’m thinking the alignment with the fid notch in the sampson
posts and the gammon iron is a little off. I’ve clearanced the chafed area
under the sprit by sanding and protected it with a thin layer of West
epoxy. I’ll also radius the edge of the gammon iron. I know there have
been a couple of sprits having water damage problems…this might be the

Spade Anchors: Last year I was using an Alloy A80 Spade (15 1/2
pounds) as my everyday anchor. Wanted the light weight so it could stay on
the rollers on my bow sprit and don’t need over-kill holding power because
most of our anchorages in the Great Lakes are fairly well protected. (also
no hurricanes so far) In sand or our sand/clay mix bottoms, the setting
and holding were incredible. In mixed or weedy bottoms it wouldn’t set as
well as the Bruce I used on my previous boat. Seems like it doesn’t do
well when there is a lot of bottom vegetation … it balls up on the
broad flukes and prevents it from digging in. I switched to a 22# Delta
this season and it worked much better in the anchorages that had challenged
the Spade. Judging by the effort required on retrieval, the Spade’s
holding in clear, weed free bottoms is better but we have hung on the Delta
up to 25 Kts so far with no problem.
If any of you anchor in nice sandy bottoms, I would be happy to
sell the Spade for $250 and shipping. I have way too many anchors…I’m
turning into Roger and will have to raise my water line again if I don’t
reduce my inventory.

Tom Harrer
S/V Whitewings III

We installed a Lavac in IDUNA. My observations regarding the vented loop in the inlet hose follows:
The size of the hole or number of holes?in the supplied “vent button” determines the amount of water left in the bowl. Lavac, England, recommends starting with a small pin hole then increasing the number of pin holes to control the amount of water left in the bowl.

  1. The smaller the hole, the more water left in the bowl and the time required to break the vacuum in the bowl increases,
  2. Increasing the number of pin holes in the vent button, decreases both the amount of water left in the bow and the vacuum break time.
    The discharge hose loop only needs to be above the waterline for overboard discharge.
    I see no reason that would prevent discharging the head directly into the holding tank without an anti-siphon device installed in the discharge line.?Our Lavac manual is on the boat but I believe Lavac shows this arrangement. We will check the manual this afternoon.
    To decrease the amount of water pumped into the holding tank, we pump the “vacuum pump” about three times, close the inlet seacock, then pump the head until liquid ceases to flow through the holes. The “flow gauge”?is an estimate?based on the input feel?from the pump handle and the amount of air sucked into the inlet hose vent button. This is determined by the sound the air makes as it passed through the pin holes in the vent button. You probably already know the sound.
    Our general observations about holding tanks is a 20 gallon tank will last perhaps 5 days for two people with careful use of the head. This?subject is probably one of?common topics between cruising boat owners.??After?the city of?Baltimore dumped several thousand gallons of raw sewage into?Baltimore’s Inner Harbor last year?and turn the harbor water green with?algae, it sometimes makes one wonder how much holding tanks help the Chesapeake. It was officially?called an algae?bloom but the cause was never told to the public - “backdoor politics.”
    Lenora and I viewed the images you posted. Whitewings II is beautiful. The contrast between the dark hull and the deck/cabin sides are striking. She appears to be well kept and is a testimony to?her owners care.
    Fair Winds,

Zygote has her GPS antenna on the boomkin (starboard side). That
location places the antenna low, which minimizes the effect of roll
and is recommended by some authorities. But other boats have higher
GPS antennas without reports of problems.

Zygote has a Freehand windvane, mounted on the backstay, and I’ve not
known this to cause any problem to the GPS antenna.

Zygote’s GPS antenna is, because of its location, less than 2 feet
from the GTO-15 wire leading to her insulated backstay (the GTO-15
wire plus the insulated backstay serve as my MF/HF antenna). That
means that the GPS signal on her electronic navigation network gets
wiped out when I transmit MF/HF. I’ve not found it a problem (in part
because Zygote’s VHF DSC radio also displays the GPS location and the
VHF happens to have a low frequency refresh, so it doesn’t notice
that GPS signal is gone - if I need to read the GPS lat/long when
transmitting SSB, I just read from the VHF display).

Your idea of a display on a swing arm is good. Sumio has a nice
installation on BCC28 #121. Sumio found exquisite (but expensive)
slide out arms when he was building Zygote, so she has her
radar/charter display (and forward looking sonar display) on slide
out arms that put the info in the center of the companionway, for
easy reading from the cockpit. Zygote has a clear polycarbonate (?
Perspex?Lexan) drop board that replaces the top wooden drop board, so
the nav data is visible even when we have to batten down for rough



Zygote, BCC28 #116, in Penang, Malaysia


Hi Tom,

Aloha has a very, very nice swing out GPS Chart Plotter. I’m going to get a
combo Radar Chart Plotter (Raymarine probably) so that I just have one thing
to swing out. I’d not go with slide out things as I’ve seen that
installation. Get the most benefit packed into your display. We gotta have
it in the cockpit in front of us. That’s my idea. My swing thing came from
“Captain Jack”. It is perfect.

Kate Christensen
RogueWave Yacht Sales & Services, LLC.
1806 Dreams Landing Way
Annapolis, MD 21401 USA
410 571-2955 Office
410 703-5008 Cell
801 681-9741 Fax