Parts for main boom

[Ronar M]

Hi All,

The aluminium fitting at the after end of the main boom on Ronar M is very worn from 40 years of the main sheet upper block shackle wearing against it. When I took Ronar out of the water for the winter I brought the boom home to get the slot in the fitting built up with weld. Unfortunately, on the way, the worm gear housing and associated fittings fell off (they are only held on by a single central nut and bolt, the nut having to be loose to allow the boom to rotate for the original round boom reefing system (which I no longer use)to work). I should have thought of that.

I am going to have to get some new parts made unless anyone out there has an old boom from which I could scrounge the parts. As I said, I no longer use the worm gear as I changed to slab reefing some years ago and, luckily, the main gooseneck fitting was left on the mast. However, short of someone having an old boom they could sell/donate, a photo of the set up would be helpful to whoever I get to make the new parts I need.

Here’s hoping, yours, Trevor

[Van]

Hi Trevor, have a look at the photo here:

(be patient for this to load, web server is sloooowww).

Is this what you mean? I would assume if you are having some parts remade, you will need to have some dimensions. I just took off the sails yesterday so the boom is free and clear to take photos with a tape measure in them. How much did you lose? I never took off the roller mechanism. I reckon it just gets in the way – maybe this is a chance to make a replacement that has the fittings/attachment points you want!

Let me know what dimensions you need and I can easily measure them – obviously the distance from the pin in the gooseneck to the start of the aluminum boom is an important one. I’ll be down on the boat a lot over the next few days as we are doing some engine work and I have to winterize the systems. You can email me at v a n e d e n (at) hotmail.com – no spaces of course.

Cheers,

Van

[Ronar M]

Hi Van,

Thanks for that. It’s amazing how you sail with all this gear but never study it closely so that when you lose a bit you have little idea what it looks like. Your photo has been very useful already but, you’re right, I will need some dimensions. Since I wrote, an ex student of mine, who has an engineering works, has offered to make some parts for me. I will show your picture to him and get his ideas and then get back to you about dimensions. I’m busy for the next month marking public exam papers and will not be able to get anything done on Ronar for a bit so there may be a delay before you hear from me again. Thanks again, Trevor

[zigzag]

Hi, I have basically the same boom on my nic 42 ( 4.025 long 115 Dia.)which broke two days ago. A previous owner had cut out a large window for the outhaul rope and a flush fitted jamb cleat.
Well with the addition of some corrosion and a stress crack in the aforementioned area, the boom was doomed to fail and luckily it did so in moderate winds.
As soon as I can find a nice replacement (Selden perhaps. anyone have any ideas?) The reefing system has been upgraded to a slab system so so the rotational gear is now unnecessary.
Meanwhile the addition of an inner sleeve, some welding and rivets must suffice for the present, however the parts would be available once a new or good condition replacement boom is found. Baz

[Ronar M]

Hi Baz,

Thanks for that offer. However, I have been very lucky. A former crew member who has his own engineering company is making new parts for me which should be ready in a week or two.
Your story just shows the problems which can result from cutting holes in things. I have had endless trouble with the outhaul on the mainsail and have decided to rig up a 4;1 system external to the boom. Will post pictures once it is up and running.
Incidently you may see I posted a note several years ago saying that my main boom has a slight bend (which I have learnt to live with) but there was a time when I investigated getting a new boom. Two years ago the basic boom with no fittings would have been £800 + VAT. Cheers, Trevor

[zigzag]

Hi Trevor,
Thanks for the feedback. I am rather disappointed that I am paying 600 Euros in Mallorca to get a splint welded and riveted into the boom and yes of course closing the oversize opening that was cut out. I will put a much smaller fairlead stainless plate about 500mm further aft to allow for the same concept as yours which is to put an external purchase. The moving of the fairlead opening for the main outhaul to a more aft position will allow for better purchase than before. The other issue is the two reef lines as I have had to install two SS stirrup/hat brackets on the round boom as the previous owner had only tapped in 3 bolts without enough support so that was the last accident that also cost sail battens when a reefing cheek block detached.
There was a sheeve in the boom when it was accidently opened in two pieces, Ha. How this sheeve and the internal purchase was meant to be accessed I cannot fathom except by dismounting the boom.
The issue here is in the long run these furling booms are perhaps more trouble than they are worth and in the case that the sail has been already modified for standard reefing, I think the boom should be changed. Could you please advise on the boom manufacturer that you have made the enquiry with and can, as has been suggested they match the gold anodized finish? Perhaps I could get the boom fitted in Gibraltar as using this patched up boom (with other smaller areas of corrosion) could be folly in respect of my planning to cross the pond next month. What is your solution for the reefing in the case you have a battened sail as I was planning to share the genoa halyard winch by installing a lever rope clutch?
cheers Baz, S/Y Zayda Nic 42.

[Ronar M]

Hi Baz

I plan to fix a double block to the clew of the mainsail and another one (with becket) to the same fitting the topping lift fixes to. This will give me a 4:1 purchase and I will bring the tail to a cleat on the forard end of the boom. This will be all external, the line being threaded through a couple of s/s stirrup/hat fittings.
Van & Marilyn have taken their boom to pieces and beefed up the internal outhaul purchase – you will see details on the website. I have opted for an external system – better the devil you can see. In fact, as it happens I have taken the after end off the boom to get the attachment ‘loops’ welded up – in 40 years the stainless steel shackles of the mainsheet and topping lift had almost cut through the aluminium so an engineer is dropping some weld in the grooves and reprofiling the fittings for me.
My spars have been painted white but are gold underneath. I doubt if you will be able to get a new boom with gold anodising – they all seem to be silver these days. As far as I can remember the £800 boom I was looking at was a Selden spar.
I have led my reefing pennants to the front of the boom and do not need to use a winch to tension them. I use the topping lift to raise the boom (maybe 20 degrees above the working position) and then find it very easy to pull in the reefing pennants by hand. Once the pennants are tight I drop the boom and away we go, the spare bunt of the sail being held in place by lazy jacks. Works very well and avoids the stretching of the sail which is a danger with a winch system.
Hope all this is clear. Good luck with the new boom. Cheers, Trevor

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