I’m working on the final details for mounting the radar on the mast and have a few questions:
I’m looking at this radar mast mount from Scanstrut: SC20 Mast Mount for Sail Boat Does anyone have any experience with this mount? I will have to drill 12 holes into the mast to rivet it (aluminum rivets), and I’m planning on locating it about 24" above the boom hangers. Thoughts?
There are fasteners that run up the front mast - Are these attachments for the wiring conduit on the inside of the mast? If I’m drilling a new hole for the radar cable do I have to do it to miss the conduit?
Thanks for your thoughts -
Bob Gehrman
NS30U #396 “Quickbeam”
Baltimore, Maryland
A common way to attach the radar mount is with hose clamps around the mast and run under the sail track. You might fasten the “feet” of the mount to shaped vertical bars then clamp that assembly to the mast.
The nuts marked what are these are the mounting for the wiring conduit.
Rather than running the radar cable inside the mast you might consider surface mounting glue on wire tie bases to the front of the mast. Easy, no holes in mast. Put a wiring gland in the deck forward of the mast.
Bob,
I was pleasantly surprised to open your email and see a picture of my former Nonsuch 30U “Carpe Diem” #484 at anchor at Harbor & Hall Islands in Muscongus Bay, Maine! You must have seen it on the recent YachtWorld listing?
The Brooks & Gatehouse radar is mounted on a Scanstrut bracket. Based on your question, I have had a positive experience with this mount. It is very solid.
I want to quickly point out that when we acquired Carpe Diem, the twelve(12) holes were already drilled & tapped for a previous radar unit, plus a hole for the radar cable.
I think you’ll find that the general consensus from this INA Discussion Group is to minimize any/all holes in a Nonsuch mast.
That said, during the marine survey to acquire, we used a magnifying glass to inspect the entire mast and found no issues. Although I understood the preferred approach was to use clamps, I decided to continue use of the Scanstrut with machine screws. The prior owner had removed a non functioning radar unit. My marine electronics installer fashioned a piece of “Star Board” to mount the new B&G unit onto the Scanstrut. The previous owner had saved everything from the Scanstrut bracket, including machine screws but I used new machine screws & lock washers to attach the Scanstrut bracket to the mast.
As Ward Woodruff confirmed, the nuts on the leading edge of mast are for the wiring conduit, which is wide enough for the running, steaming, foredeck, VHF & anchor light wires, but not the radar cable. The installer used foam copper pipe insulation tubes, which we easily slipped through the radar cable. Virtually no weight and it eliminated any noise.
If you decide to mount the bracket using fasteners(which I’m not suggesting or recommending you do) instead of clamps, I think you should ask this INA Discussion Group about the use of aluminum rivets vs stainless steel machine screws. Among other issues, I’d think the halyards might “catch” on the splayed rivet? I think other fellows can advise better than I.
You mentioned installing your radar about 24” above the wishbone boom hangers. I’ve attached a side view of Carpe Diem prior to haul. I think my radar is only about 12” above the hangers with no issues. Keeps the weight a bit lower too.
If you’d like to discuss further, my mobile number is below. Good luck.
Eric Hakanson
Former owner of NS30U “Carpe Diem” #484
P. S. If you Google Harbor Is, Muscongus Bay, Maine, you’ll see that it’s in the south central area of Muscongus Bay, a lovely, convenient one day sail from Boothbay Harbor. It was frequently used on our cruises “Downeast”.
I got the no-go from Mike Quill about the 12 holes also. Oh well, thought I’d ask. Klacko is working something up for me as a strap-on mount.
Where is the hole for your radar cable? You said you used foam tubing to run the cable inside of? Is that to keep it from banging on the inside of the mast?
Bob,
when we bought La Reina she had radar. The scanner was mounted above the boom, just below the mast joint. The screen was in the forward cabin and the cable was not long enough to set the screen up near the companionway so it was rather useless.
Before we would leave the dock I would attach the halyard to the sail so I did not have to go forward when it was time to hoist the sail. Unfortunately if there was any wave action, the pumping of the mast would swing the halyard forward and it would wrap around the scanner. I would go forward to flip it clear (so much for not having to go forward) but it would catch on the boom before it would clear the scanner. Freeing the halyard was a pain. Later I would hoist the sail a few feet as soon as we cleared the dock. The weight of the sail would keep the halyard from going forward. There were times after I dropped the sail but before I made it forward to take the halyard off the sail the halyard would work its way around the scanner. The good news was it was easier to free the halyard the dock than in a lumpy seaway.
Eventually I removed the radar. The scanner weighed about 20 pounds. A rough estimate is that the scanner was 15 feet above the deck. Good for range but it was the approximately equivalent of a 200 pound crew member on the deck. The boat felt a bit stiffer after the scanner came down.
Of course Murphy’s law kicked in. We did not sail in fog until after I took the scanner down.
If the scanner is below the boom clearing the halyard after a wrap will be easier but the effective range of the radar won’t be as good. Dick Lane had the radar dome on his 26 mounted on the mast below the boom. The mast diameter is bigger there and he found that it created a blind spot behind the mast that a tug could hide in. He was heading back to Port Townsend in the fog and just about fell overboard when a tug and tow appeared about 15 feet off of his port rear quarter. IT showed up in his vision before it showed up on the radar.
A scanner mounted on a pole at the stern will reduce the potential blind spot caused by the mast. The top of the scanner needs to be above the heel of the boom so the sheet can’t catch on it and far enough back that the boom won’t hit the pole. It will be lower than a scanner mounted on the mast above the boom so range will be some what less.
If you don’t attach the halyard until you are ready to hoist a scanner mounted above the boom will not cause as many issues.
Sailing like life is full of compromises. Pick which ones you want to live with.
We are contemplating replacement of our Paloma on demand water heater with a hot water tank like the example shown. If we go ahead, then I am thinking about locating it in the starboard locker that is a box above the fuel tank.
In any case, has anyone installed a hot water tank like this? If so, where? Do you like it? This tank is heated by taking hot coolant from the engine and via a 120V connection.
We have one internal halyard and an external halyard (back up) that goes through a cheek block on the port side at the top of the mast and is rated for 3,000lbs. The cast aluminum mast head fitting has two sheave blocks, but one has been seized since we bought the boat. I managed to pull the fitting and free up the 2nd sheave. Now that we have two working sheaves, I would like to add a 2nd internal halyard. Meaning I need to cut an opening in the mast, likely somewhere near the opening for the existing internal halyard but on the opposite side of the mast.
Doing this will declutter the lines. Also, we could get rid of the flag halyard which is on its own lighter duty cheek block. On the rare occasion we want to sport our flags we can use the spare halyard rather than a dedicated flag halyard.
Has anyone done this? Any words of wisdom, instructions, detailed engineering procedures😊you can share?
We have one internal halyard and an external halyard (back up) that goes through a cheek block on the port side at the top of the mast and is rated for 3,000lbs. The cast aluminum mast head fitting has two sheave blocks, but one has been seized since we bought the boat. I managed to pull the fitting and free up the 2nd sheave. Now that we have two working sheaves, I would like to add a 2nd internal halyard. Meaning I need to cut an opening in the mast, likely somewhere near the opening for the existing internal halyard but on the opposite side of the mast.
Doing this will declutter the lines. Also, we could get rid of the flag halyard which is on its own lighter duty cheek block. On the rare occasion we want to sport our flags we can use the spare halyard rather than a dedicated flag halyard.
Has anyone done this? Any words of wisdom, instructions, detailed engineering procedures😊you can share?
Nonsuch Luck was delivered from the factory with two sheaves and two halyards. As you point out this requires two exit holes in the mast. These are 19 x 110 mm (¾ x 4.33in) and positioned on opposite sides of the mast but offset vertically. The main halyard exit hole is centred 4.215m (13ft 10in) from the bottom of the mast (with the boot casting removed) whilst the secondary halyard is a bit lower at 3.745m (12ft 3½in. It is recommended not to drill any holes in the mast nearer to the deck partner than 2m (6ft 6¾in) so these holes are above that limit.
It is important to clean the edges of the holes carefully with a fine file followed by fine-grit sandpaper.
Bob Illingworth
Nonsuch Luck 30U #367 (GBR1262T)
Moored Titchmarsh marina, Essex, UK; cruising the rivers of East Anglia, and, the North Sea.
Here’s a photo of my radar on 30U, taken today with a snow cap. It’s mounted to mast with long hose clamps through plastic tubing (hose?). I believe to avoid contact between stainless clamp and aluminum mast. Probably also grips the mast better. Also see radar wire access hole in mast.
This was done by yard for previous owners in 2017. I think there was an older radar mount there before.
Hope that helps.
Don
‘87 NS30U #369 Breezin’
Vancouver, BC
. It is recommended not to drill any holes in the mast nearer to the deck partner than 2m (6ft 6¾in) so these holes are above that limit.
