VHF cable through Selden mast

Nina Lucia

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Will I be able to run VHF cable through the trunking on the keel-stepped Selden Mast, the boat is Aphrodite 36.
A long time ago, someone fitted through the sail track, and now, every so often, pops out.
 

TSB240

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I recently had to rewire our VHF cable on a keel stepped mast with internal trunking containing wiring for VHF MH light, MH wind unit, Radar and steaming light.
New VHF was a military spec large OD low loss vhf cable not the usual thin crap that comes with a replacement antenna.
I initially tried pulling out the old cable with the new cable attached. This worked fine until it got to the pinch point with all the cables in the trunking and my soldered and taped connection broke.

The trunking inside my Mast was 20mm dia plastic ducting. This is really too small for all the cables!

Eventually I pulled the blue three core arctic cable for the mast head light out. I replaced it with a lighter gauge three core, VHF Coax and a spare mousing line!

Most mast head lights are LED now and don't need heavy duty cables. 0.5mm three core works for fine for me.

Some cable installation lube or PTFE spray might have helped.
 

vyv_cox

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My VHF cable runs through the trunking alongside the sail slot on a Selden extrusion, 1985 Sadler 34. When I first owned the boat somebody had taped the VHF cable to the masthead light power supply, forcing me to pull both out when replacing the antenna. I found some heavier VHF cable that was too thick to fall through the gap into the sail slot. Failing that a few short lengths of tubing just tight enough to slide over the cable should keep it inside the trunking.

A method used for inside the mast is to fit cable ties at about half metre intervals, leaving the tails attached to centralise the cable in the mast. I thought this was likely to cause problems in the small trunking.
 

noelex

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Most modern Selden masts have an integrated conduit for wiring. I’m not certain when this feature was introduced, but refer to the details for your specific mast section (the model number is usually engraved near the base) to understand the design of your profile.
 

DanTribe

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in my Selden E-section mast the cable duct is part of the extrusion alongside the track groove but has a conitnuous opening on one side. This is wide enough to let the VHF cable escape.
I overcame this by wrapping a few turns of electrical tape every meter or so to fatten the cable. Has lasted about 15 years so far.
 

Nina Lucia

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Thank you! I will check the model number tomorrow. Hopefully, I will be able to run through the trunking without lowering the mast.
 

DanTribe

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Thank you! I will check the model number tomorrow. Hopefully, I will be able to run through the trunking without lowering the mast.
I think you will find that difficult / impossible because the exit at masthead is usually a very tight turn. I had to remove the mast cap to run my cable.. I wouldn't want to try it from a bosuns chair.
Good luck!
 

Nina Lucia

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I think you will find that difficult / impossible because the exit at masthead is usually a very tight turn. I had to remove the mast cap to run my cable.. I wouldn't want to try it from a bosuns chair.
Good luck!
😮‍💨 Dropping the mast down is not cheap,
I'll try from my bosun chair first if I can find right place to get in to the mast ducting at the top of the mast, as soon as weather gets little bit warmer. Thank you
 

st599

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😮‍💨 Dropping the mast down is not cheap,
I'll try from my bosun chair first if I can find right place to get in to the mast ducting at the top of the mast, as soon as weather gets little bit warmer. Thank you
Drop a length of old bike chain down on some string, fish it out at the bottom, then attach cable to string. Fiddly, but doable.

If you're going to the trouble of doing it, radio suppliers are your best bet. You can get less lossy cable, which is lighter and easier to bend and more abrasion resistant for a similar cost to chandlery co-ax. Worth ringing them and seeing what you can get - there are some very thin co-ax cables now with similar performance to RG58.
 

vyv_cox

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Drop a length of old bike chain down on some string, fish it out at the bottom, then attach cable to string. Fiddly, but doable.

If you're going to the trouble of doing it, radio suppliers are your best bet. You can get less lossy cable, which is lighter and easier to bend and more abrasion resistant for a similar cost to chandlery co-ax. Worth ringing them and seeing what you can get - there are some very thin co-ax cables now with similar performance to RG58.
He needs thicker, not thinner, to prevent it from passing through the gap into the sail slot.
 

pandos

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Will I be able to run VHF cable through the trunking on the keel-stepped Selden Mast, the boat is Aphrodite 36.
A long time ago, someone fitted through the sail track, and now, every so often, pops out.
Selden sell little foam plugs that are pushed into the track to stop the cables escaping...when I rewired my mast I did not know about these and I removed what were piece of green scrubbers..which had been when the mast had last been rewired.

Wires popped out after a few years and eventually I had to break them off just to be able to raise the sail and be sure I could drop it again. (For health reasons I was not able to climb the mast and I couldn't find a volunteer to go up it .)
 

noelex

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in my Selden E-section mast the cable duct is part of the extrusion alongside the track groove but has a conitnuous opening on one side. This is wide enough to let the VHF cable escape.
I overcame this by wrapping a few turns of electrical tape every meter or so to fatten the cable. Has lasted about 15 years so far.
Some Selden mast sections have a sealed (an opening at the top and bottom only) electrical conduit, so this not always an issue.
IMG_7696.jpeg
 

vyv_cox

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Some Selden mast sections have a sealed (an opening at the top and bottom only) electrical conduit, so this not always an issue.
View attachment 189071
These are relatively new sections in current production. I have found this collection of old sections https://www.kayospruce.com/kayo/pdf/Sailmakers guide_Selden.pdf. My section, and I am guessing the OP's, from memory is letter E with the 10 degree aft face. The cables run through the open conduits adjacent to the sail slot.
 

Nina Lucia

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Drop a length of old bike chain down on some string, fish it out at the bottom, then attach cable to string. Fiddly, but doable.

If you're going to the trouble of doing it, radio suppliers are your best bet. You can get less lossy cable, which is lighter and easier to bend and more abrasion resistant for a similar cost to chandlery co-ax. Worth ringing them and seeing what you can get - there are some very thin co-ax cables now with similar performance to RG58.
Thank you
 

st599

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He needs thicker, not thinner, to prevent it from passing through the gap into the sail slot.
If going thicker than RG58, you can vastly improve the performance, but the issue then is keeping within the larger minimum bend radius. That's quite difficult, especially in the deck entrys.
 

Nina Lucia

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Our one looks looks like Longitudinal oriented F-section. I just hopping that there is access hole a the top to the trunking.
If going thicker than RG58, you can vastly improve the performance, but the issue then is keeping within the larger minimum bend radius. That's quite difficult, especially in the deck entrys.
Thank you, what would be thicker equivalent to RG58? What shall I look for on line or chandlery?
 
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