Mast wiring

Post by **Russ** » Sun Mar 16, 2008 4:44 pm

I'm thinking of installing a masthead VHF antenna.

What's the best way to pull the wire?

Does the wire clank inside when the boat rocks? We had a boat that drove us nuts with internal wires clanking inside when the boat would rock. I ended up wrapping them in foam (pipe insulation) to silence them.

Post by **NiceAft** » Sun Mar 16, 2008 5:05 pm

My understanding of the M mast is that it is filled with foam. Those who have done electrical modifications which required running wires through the mast have made posts. Do a search!

I mounted my antenna on a starboard stanchion.

Here is another shot with the antenna down.

Ray

baldbaby2000 · Post by **baldbaby2000** » Sun Mar 16, 2008 5:11 pm

My mast has foam plugs in it. The dealer made a makeshift "drill bit" with a long piece of pipe with notches filed in the end so it cuts through the foam. Seems like he must have had a rod welded to it so it can go in the drill. No wires clanking on our boat. Seal the foam at the top when your're done.

Jack Sparrow · Post by **Jack Sparrow** » Sun Mar 16, 2008 5:27 pm

The mast is filled with flotation I cut it out by using 1 1/2 plastic plumbing pipe on one end of the pipe I filed cutting teeth and the other end drilled a hole through the pipe and inserted a turning bar. Rotating the pipe and pushing it down the mast (starting at the mast head) cutting about a foot the it requires it to be removed and the core cleaned out from the centre if the pipe. The pipe then remains in the mast and the coax' is fed down the centre of it. Now to answer your question the coax cables do slap on the inside of the raceway and require attachment points down the mast raceway, this job is on my winter lay up list

Jack Sparrow

Shane · Post by **Shane** » Sun Mar 16, 2008 7:59 pm

Russ,

As has already been pointed out, there's work involved in fishing that wire up the foam filled mast. Given your other posts on site, I'm assuming you'll be rigging the mast at least at least a handful of times each year (presuming summertime moorage with fall, winter, spring trailering). That means you'll have to deal with some sort of coupling at the mast base as well.

I'm looking at the same issue right now and have pretty much decided on mounting a 3db anntennae on the stern mast support. The only delay is deciding how, and by how much (if at all) I need to elevate the antennae
for radiated energy. While I know that it not much (energy), but I recall seeing figures somewhere that stated the base of the ant. should be 6ft above head height. Unfortunately, I don't remember where/how I came across that info, so it's a little bit of blind search. I know many people have installed under that height, and I don't have any problem with doing so, as long as I know it's not a safety issue (but there are a lot of follically challenged sailors on this site

) . I know the loss of elevation is an issue, but I'm sure the 20ft vs 50ft of co-ax off sets some of the signal strength -if not the line of sight

As is everything he does, Duane's site (www.ddunn.org) has photos of a very nice, clean install on his new arch.

Safe drive home, btw.

Regards,
Shane

Boblee · Post by **Boblee** » Sun Mar 16, 2008 8:02 pm

I think Synergy Yachts only use a bit of 3/4 conduit which would stop the cables rattling probably.
I think Phillip also runs some lines down there too but maybe he uses a separate conduit for that.

Terry · Post by **Terry** » Mon Mar 17, 2008 8:24 am

The PVC pipe with teeth cut into it works just fine, starting from the mast top you only need two 10' sections to clear the last piece of foam which is just above the running light on the mast, from there you can jiggle it the rest then grab it with a long coat hanger. Be sure to send a long peice of fishing line down there with it in case you want to add a wire later for a mast head light or something, makes it easier to pull one through with the fishing line. I left my PVC pipe in the mast to prevent any wires from slapping the internal mast although I may take them out this season, not sure it is necessary. I thought I could get by with inexpensive coax but have since learned that I will ahve to replace it with RG8U, RG213 or RG8X to compensate for the 50' length I use. I should be using a thru deck fitting to connect inside but I found the 50' pre-cut, pre-fitted ends could be secured to the hatch rails with loops holders and still be long enough to reach the bow when trailering. When I replace it I will have a look at going thru the deck although I do not like the idea. I prefer a 50' length all professionally done so all I have to do is put it on the boat and up the mast.

Catigale · Post by **Catigale** » Mon Mar 17, 2008 9:44 am

I had Caitlin stand at one end and guide the coax after I had run a fishtape down mast while it was on the trailer. Remove the mast step end to do this really easily.

The trick to stopping the wire from rapping (the annoying kind, not the rhyming kind...wait a minute, not enough differentiation...... I mean the non-musical kind...) is to put a ziptie on the coax every couple of feet. .....to be precise my Cray calculates they should be installed every

e/pi metres

but 2 feet will do for the blue hulls groping for yet another excuse of a lost race

baldbaby2000 · Post by **baldbaby2000** » Mon Mar 17, 2008 11:54 am

I think the reason our dealer didn't put conduit in the mast was because of the extra weight.

Post by **Russ** » Mon Mar 17, 2008 1:06 pm

Interesting. So there's foam in that thing.

The PVC "drill" idea sounds clever. I would imagine the cable running through the core wouldn't clank either. Then just the bottom half needs to be secured. That cable tie idea is clever. The last time I wrapped the wires with pipe foam insulation.

I'm leaning towards a mast head antenna because VHF is line of sight and altitude matters.

K9Kampers · Post by **K9Kampers** » Mon Mar 17, 2008 1:14 pm

I did same as Cat for my masthead all-around light, except with triple - star pattern ties every two feet. Looking to add mast antenna this year.

Highlander · Post by **Highlander** » Wed Mar 19, 2008 7:55 am

According to the mac site thier is supose to be a channel inside the mast now & on the inside of the cabin liner for the purpose of running extra wiring through the boat this might be on 2008 models I guess I'll find out soon enough when I start doing my upgrades , mods

J

Moe · Post by **Moe** » Wed Mar 19, 2008 4:37 pm

That wording about a channel through the 26M mast has been on the MacGregor website for five years now. Same for the large optional cooler that fits in the aft dinette seat, IIRC.

Highlander · Post by **Highlander** » Wed Mar 19, 2008 5:16 pm

Moe

You just burst my bubble

I guess things are going to take alittle longer now

J

Post by **Hamin' X** » Wed Mar 19, 2008 10:39 pm

Shane,

Maybe this chart will help:

Use the 2m/144MHz and assume 50 watts continuous, unc(uncontrolled).

Rich---Hamin' X---N7ZH

MacGregorSailors.com

MacGregorSailors.com

Mast wiring

Mast wiring