Running wire down a mast... - Page 3 - SailNet Community
LinkBack Thread Tools
post #21 of 25 Old 07-10-2013
Senior Member
rugosa's Avatar
Join Date: Aug 2011
Location: In a strange land
Posts: 578
Thanks: 1
Thanked 10 Times in 10 Posts
Rep Power: 6
Re: Running wire down a mast...

If you are going to buy the fish tape and ultimately store it aboard, make sure you extent it full length after the job and protect with lube film before coiling back in the disc, avoids the ugly rusty coil next time around All tools should be properly maintained, and only loaned out VERY sparingly
rugosa is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
post #22 of 25 Old 07-10-2013
sailing soon
mark2gmtrans's Avatar
Join Date: May 2013
Location: Texas
Posts: 813
Thanks: 2
Thanked 31 Times in 30 Posts
Rep Power: 4
Send a message via Yahoo to mark2gmtrans
Re: Running wire down a mast...

Originally Posted by JulieMor View Post
Electricians NEVER try to blow a line through conduit that already has wire in it. That only creates problems as the mouse (whatever you tie the string to) will get snagged on, or pinched between, the wires. Most mast chases (usually a plastic conduit) already have wire in them. Trying to blow a string through them is an exercise in futility.

When the conduit is empty we use foam cylinders with a nylon jet line attached to it and blow it through with compressed air (CO2 or a compressor) or suck it through with a vacuum. The longer the run, the less effective the vacuum. I've used a full size compressor for really long runs in larger conduit.

While the foam cylinders can be found on most jobs and are often used, a baggie with a jet line attached to it can work better, especially on smaller conduits. But you typically don't see vacuums or compressed air used on short runs. We typically use fish tapes. And of those different types, the spring steel are most commonly used, but we're talking metallic conduit.

In the mast, I'd choose the slinky. As you are dropping it down, you can easily spin it if it gets caught and it will find its way through. But they're not cheap. A 50' Sparks will cost you about $75.00. That's why I didn't initially suggest it.
Why that was silly of you not to suggest it when it was nearly free in comparison to everything else used on a boat ...LOL

I never have had any real problems with a steel fish tape, but I have only run maybe a few thousand yards of conduit, well maybe a couple of dozen miles, only four or five buildings worth and they were not huge. On some jobs we used a huge Joy Compressor like you run a jack hammer off of to blow the line through, and a huge glob of that old yellow snot stuff, what was that called, yellow 77 or something like that, but thank goodness I have not had to do that since I was a kid.

I would buy the slinky thingy, just because I would love to have a really good one to work on other people's boats, next time I go to Granger's I will have to get one. Maybe I can figure out a way to fit all the tools I like to carry onto a boat smaller than the Queen Mary

It is good to learn from your mistakes, but much better to learn from the mistakes of others...
mark2gmtrans is offline  
Quote Quick Reply Share with Facebook
post #23 of 25 Old 07-10-2013
Over Hill Sailing Club
smurphny's Avatar
Join Date: Feb 2009
Location: Adirondacks NY
Posts: 3,663
Thanks: 93
Thanked 111 Times in 108 Posts
Rep Power: 9
Re: Running wire down a mast...

We used to call the yellow pulling lube "goose grease." +1 on using a plain old steel fishtape.

Alberg 35: With a philosophical flourish Cato throws himself upon his sword; I quietly take to the ship.
smurphny is offline  
Quote Quick Reply Share with Facebook
post #24 of 25 Old 07-10-2013
Senior Member
JulieMor's Avatar
Join Date: Sep 2011
Posts: 853
Thanks: 47
Thanked 16 Times in 16 Posts
Rep Power: 6
Re: Running wire down a mast...

Originally Posted by mark2gmtrans View Post
On some jobs we used a huge Joy Compressor like you run a jack hammer off of to blow the line through...
That takes me back to my first year apprenticeship. The foreman, a journeyman and I were blowing water out of underground conduits to prepare for wire pulls. It was the end of the day and there was a short run of about 500' of 2" conduit. I was the signal relayer. The foreman walked into a building to make sure everything was clear then came out and gave me the okay to let 'er rip. I waved to the journeyman to open up the compressor and turned to see the foreman disappear back into the building. About a minute later he walked out swearing and soaked, but just the front of him. The back was bone dry. The water hit the top of the panel and shot right out at him.

About 20 years later I ran into the journeyman who was on the other end and he was still laughing about it.
JulieMor is offline  
Quote Quick Reply Share with Facebook
post #25 of 25 Old 07-10-2013
Senior Member
redline's Avatar
Join Date: Feb 2010
Posts: 201
Thanks: 9
Thanked 10 Times in 9 Posts
Rep Power: 8
Re: Running wire down a mast...

I second the comment about taping the hook end of the flat fish tape. I (attempted to) use one to run the new radar cable (from mid-mast no less) through an internal conduit (a slit PVC pipe fitted over a "T" on the inside corner of the mast extrusion).

Two problems - said PVC pipe was not one continuous run, apparently about halfway along the tape exited the conduit in the gap between one section and another, then went the rest of the way somewhere in the middle of the mast. Then when trying to pull the fish back it became clear it was stuck for good, and eventually I had to resort to cutting the fish and going back to "plan A" (which apparently everyone else does), namely pulling out the nav/deck light wire and using that to pull through a string, then the radar cable and replace nav/deck light cable. My concern about losing the existing cable (as the original poster did) was what prompted me to try the fish tape instead. In the end, the "old way" worked better.

I hate to admit that, as the mast was laying on the boat on its cradle, with the bottom end hanging about 4' aft of the the stern and some 14' off the ground, I did not notice when the fish tape reached the bottom... and hooked on the end of the mast itself. It had in fact exited the conduit about half-way, but I missed my measurement and hadn't realized I'd fed enough fish to reach the end, which was on the "far side" of the mast, between the furler, shrouds, halyards, and all that "stuff" that gets bundled with the mast when it's stowed for transit, and so invisible. Was kind of surprised when the cut section slid out the bottom so nicely. So I now have two fish tapes.

In short, tape the end, watch that hook, and if you have a conduit, it may not be a single piece.
JulieMor likes this.

s/y "Redline"
1998 Jeanneau SO45.2
redline is offline  
Quote Quick Reply Share with Facebook

Quick Reply

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Forum Replies Last Post
Re-wiring mast...What size wire? rhr1956 Gear & Maintenance 11 02-11-2013 11:47 PM
mast wire ambianceack Gear & Maintenance 3 01-14-2011 08:54 AM
Connector for running a wire through the deck arf145 Gear & Maintenance 8 01-29-2010 05:11 PM
wire halyards damaging mast dancamp Gear & Maintenance 12 10-06-2008 03:32 AM
Wire tube in mast loki Gear & Maintenance 3 03-26-2001 06:50 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome