Fitting mast conduit

[Yellow Ballad]

One of my jobs was to fit mast conduit while the mast is down but I'm struggling settle on the best option.

I had settled on using corrugated flexible conduit with cable ties and tails but the more I think about it the more I'm thinking I may be better using 32mm PVC waste pipe rivited to the inside of the mast.

What are people's thoughts on how to fit the pipe to the mast? Rivet spacing (2m ish)? How to hold it agaist the mast whilst riviting it(mast head/cap is welded on)? I did think about laying everything out externally but I'm guessing the law of sod will means it'll not line up once inside. My other thought was drilling two holes one above the other and feeding a loop of wire through to snare the pipe and hold it up whilst it's drilled and rivited through the other hole?

I'm probably over thinking it but is there an easier/better way?

 

[The Q]

The question is why use conduit? I don't think the wear on a cable would warrant the problem of fitting it and if so you could always get armoured cable..

 

[john_morris_uk]

I've heard of people putting a pattern of cable ties with the tails still attached in a star pattern every metre or two on the table to stop it slapping around inside the mast. Some mast sections come with extrusions for cables built in?

 

[neil_s]

I would suggest that rivets wont hold very well in plastic pipe, if you go down that choice. The conduit in my mast is thin alloy pipe.

 

[Yellow Ballad]

Noise, my cables are loose in the mast and clatter about when trying to sleep. I don't want to cable tie them together as I may need to run another wire in the future.

I was going to try the cable tie route with the flexable conduit but part of me wonders if it'll just become one big cable that the cale ties can't dampen.

No extrusions in my mast.

 

[Motor_Sailor]

It's quite possible to use plastic conduit and you can get pop rivets that 'butterfly' out inside the conduit and don't pull through.

Some tips:
• Glue all the bits of conduit together so it is one solid length. Don't rely on friction in the joints.
• Drill a pair rivet holes in the mast (50mm apart on the upright mast's vertical axis). These must be at exactly 2000mm centres.
• Lay the conduit out along the mast and securely tie one end of a length (~ 300mm) of 2mm strong line around the conduit to correspond to each of the 'upper' holes of each pair. Leave the rest of each length of the line as a 'tail'. Again these will be at the same exact 2000mm centres. Use some hot melt glue to ensure the bits of line can't move when you slide the conduit up the mast.
•Lay the mast so your line of holes point perfectly down to the ground.
•Slide the conduit up the mast so each piece of line corresponds to the 'upper' hole in the pair.
•Use a rigger's hook (bent piece of stainless strip out of an old windscreen wiper / welding rod) to fish each 'tail' out of the 'upper' hole.
•Tie a nail or something to the outer end of each bit of twine so it can't disappear back in the mast.
•Roll the mast over to a convenient orientation.
•Pull the conduit towards the hole with the twine and when it's tight, drill its next door rivet hole and 'pop' it. Then cut as much twine off as you can and drill and pop what had been the 'twine' hole.
•Move along to the next pair

 

[Yellow Ballad]

This was the sort of thing I was thinking.

I'm still in a quandry to know what's best, my only other worry about conduit is trapping a mousing line underneath it causing issues when the last goes up also conduit getting around boom roller spindle/spreader bar meaning the holes nolonger line up. I think it calls for a trip to the boat and have a proper look.

I have 100 10mm wide cable ties sitting here in a bag, I might just go with plan A and if the slapping doesn't stop have another attempt next year.

 

[doug748]

I have done this on a 26 foot fractional rig. It had a removable heel and cap fitting so I could get into both ends. I removed everything (wires and lines) from inside the mast first.

It pays to set the mast up for maximum convenience, I was under cover with access to good lights and power with the mast supported at somewhat below shoulder height. I could walk right around it and had access to a number of different lengths and section of rods and battens.

The conduit was standard stuff, I can't recall but something like this, jointed into one long, straight length about a foot short of mast length, at both ends:

JG Speedfit 22BPEX-78028 Push-Fit PE-X Pipe 22mm x 3m

I pre drilled the rivet holes in the mast c1m apart and then shoved the pipe in position (with a single mouse line attached for rigging use later). By rolling the mast and pushing packing of rag and foam up the mast it was possible to jiggle the pipe so it could be seen though the rivet holes . They could then be drilled and riveted, one at a time. The middle of the mast was a problem and I resorted to pushing a red hot wire into the conduit where drilling proved difficult.

I can't recall what I did about the steaming light. I suspect I may have wired it separately at the start.

.

 

[bluerm166]

When I did this on a 11M mast I found ordinary plastic electrical conduit fairly easy to install using the standard couplers.I got a length of 16mm studding ( or what have you) notched one end to take a mouse line and gradually pulled it along inside with the conduit lying in position at the bottom of the horizontal mast so that I could hole- for and rivet the fixings .In fact I used a cheap pointed solder iron to pierce initial holes in the tough plastic first ,so no pressure involved , allowing a self tapper to hold the conduit fast temporarily and make drilling clean and reliable.I found my old plastic covered forestay ( from within rotostay ) to be absolutely invaluable as a push or pull mouse ,being longer than the mast.A drawing also helped to keep track of what should be going where.

 

[Stemar]

Would the bit of rivet sticking through the inside of the conduit be an issue feeding cables?

 

[Daverw]

Use smooth bore solid as flexible would be so difficult pulling stuff through

 

[Richard1952]

Could you not use pipe insulation as a conduit? No fixing required and very much quieter than free cables

 

[Ardenfour]

I forget the title, but in one of his books Ian Nicholson gives an in depth description of his method of inserting and fastening either a conduit or track in his mast

 

[Yellow Ballad]

Who's the muppet that didn't look properly up the inside of the mast, nice piece of aluminium conduit already in there but about an armslength up. All cables taken out and replaced through the conduit which was a pain but hopefully worth it.

Thanks for the input, hopefully it'll be worth it.

 

[andsarkit]

Who's the muppet that didn't look properly up the inside of the mast, nice piece of aluminium conduit already in there but about an armslength up. All cables taken out and replaced through the conduit which was a pain but hopefully worth it.

Thanks for the input, hopefully it'll be worth it.

Well done, but at least it generated an interesting discussion.
Did you feed in a spare light mouse line for when you next need to add another cable?

 

[Yellow Ballad]

Sure did but it.

Something I noticed (peeking through the tiny gaps) was the top of the conduit was cut and squashed to an oval meaning cables had to be pulled from the bottom up. I assume to grip the cable insulation so not to put strain on the connections. There was a convenient cut out for the steaming light cable as well.

Thank god for wire coat hangers.

 

[Mait]

Could you not use pipe insulation as a conduit? No fixing required and very much quieter than free cables

Interesting idea!