Snapped off mast brackets

[alandav123]

Hi all, had a spot of bad luck today whilst trying to remount the mast on a Gem Mirco I bought yesterday.
We laid the mast along the deck but the mounting hole did not line up, we then were told it would be better to put a thinner bolt through the hole then hoist the mast up and then it would be easier to get the correct pivot bolt inserted.
Well it did not work and we lost control of the mast and it fell over, ripping the flange affixed to the bottom of the mast and badly bending the deck mounted bracket.

My question is would I be better to get an exact origonal of the broken one OR is the a more modern upgrade that would allow easier mounting.
It does seem strange that it was virtually impossible to get the bolt in using both in the lying down and upright mast position.

I have drilled out the broken mast fitting and removed the deck bracket and its just a question of what to do next?

From a purely engineering point of view, I would have thought that it should not be that difficult to mount a mast on a small trailer sailer like this.

Regards and thanks
Alan

 

[VicS]

That's rotten luck. I dropped mine once, fortunately the screws holding the mast step to the deck pulled out and there was no serious damage.

I expect you will have to make do with what ever you can find. I don't know when the Gem Micro was in production but finding spares might now be difficult. If you can identify the mast maker and they are still in business maybe they will be able to help but even that's a long shot as mast sections change over the years.

I can't comment on why the bolt was so difficult to fit, mine is not that bad. It was not a contributing factor to the mishap though!

Keep the broken bits you might need them as a pattern to get a new one made.

 

[William_H]

The problem you have had is not uncommon around here where boats lower masts for going under bridges. I have a friend who has about 45ft of mast and it got out of control when a mobo went past while mast was in transit from up to down.

The bolt size in the bracket should have been OK being smaller. The thinng is you must maintain the mast on the fore and aft line of the boat at all times from down to up.

This can be acheived in several ways. For a mast head rig where the side stays are abeam the mast the best method is to extend the chain plate up to a poi9nt exactly in line with the mast pivot bolt. This means that the cap shrouds are tight from down to up so holding the mast in the aligned with centre line.

If you have a fractional rig then it is more tricky because the cap shroud chain plates are aft of abeam the mast so do not tighten untinm the mast is vertical. I use (occasionally) a couple of cable clamps on the shrouds about a metre up from the chain plate. I attach a rope to this point and run it forward to a pulley then back to a cleat. This rope is duplicated each side and is pulled tighter as the mast goes up to hold the cap shrouds tight.

A very smooth system gaining popularity here is to have 2 poles (spin poles would do) that pivot on purpose made steel loops on the deck a little aft of abeam the cabin bulkhead and at the gunwhale.
These connect to a purpose built slider that goes up the mast track.
So if you are putting the mast up you attach the poles to the slider which would be about half way up the mast track. As the mast goes up the slider comes down the track at all times the 2 poles force the mast to stay on centre line. One rigging company is selling the system at huge cost with a rope to pull the slider down the mast so raising the mast. It seems to work although I instinctively prefer 2 poles as an A frame at the front with a tackle to pull the mast up.

However for all that with a small trailer sailer (mine is 21ft) Providing you have the A frame and tackle to raise thee mast if you stand in the cabin top holding the mast central while someone else pulls the tail of the tackle. The trick is to do it smartly as it gets easier as the mast approaches vertical. Of course it is much more stable on a trailer than bobbing about on the water.

The mast pivot or step that is really common around here has an aluminium casting on the deck with with 2 lugs rising up at the back. There is another casting plug in the mast which has also lugs at the back to take a 3/8 inch pin about 5 inches long. This type is very susceptible to damage when the mast sways to one side.
The leverage of 27 ft of mast on lugs 4inches apart is huge. The mast base can not hold the mast central if there is any force sideways on the mast like the boat leaning in the water when mast is down.

The design on my boat has a flat plate on the deck with a web about an inch high fore and aft with a raised lug at the back end. The mast has 2 lugs welded at the back end sticking out about an inch but only about 3/8 inch apart. A short bolt does the pivotting. In my case 1/4 bolt in a 3/8 hole. Plenty of slop.
This system of only one lug means there is a lot more room for the mast to sway sideways bfore there is any resistance at the step and if there is any damage it simply bends the lugs on the mast apart.
There is a slot in the base of the mast to sit over the web so holding the mast fore and aft and sideways. There is a plate welded to the bottom of the mast with the slot which hhelps take thrust loads without crumpling the mast thin edges.

You need to make up a step that is easiest constructed from the wreckage you have.

Another common design is to have a large U shaped plate on the deck which extends up the sides of the mast about 8 inches. There is a hole for a bolt near the top which corresponds with a hole through the mast. Often through a tube welded into the mast to spread the load. It is vital in this system that the bolt be very sloppy or at least have vertical movement so that when the mast is up the down pressure (which is huge) is not on the bolt but rather the bottom of the mast in the U shaped bracket. You will need to chamfer of the back corner of the mast to allow for it to pivot into the U shaped bracket.
Its a pity you don't live near here as mast riggers are very familiar with the design of mast pivots and could build /rebuild quite easily.

PM me if you want more help best wishes and sorry about your first sail being a disaster.

On my first outing with my TS I stopped the car at the top of the ramp and removed the safety chain thinking I would hit the brakes at the bottom to make the boat slide off. Unfortunately near the top of the ramp I touched the brakes and the boat slid off easily. Bounced across 20 ft of concrete and threw itself in the water. (too keen)
The outboard motor was badly damaged but the hull hardly scratched. The moral is that boating is all about crisis management initially you sail from disaster to disaster. Just enjoy the challenge.

good lcuk olewill

 

[William_H]

Gee that olewill certainly waffles on. So here is some more.
I found that a quite high A frame mast support at the transom is helpful. About 2 metres above the deck or as high as you can lift the mast into means that when you start lifting you don't have so far to go. The mast is heaviest when low near horizontal and lighter to lift once you get past 45 degrees.
What I do is have a low mast support for on the road with the base at the bow rail. I lift the mast up to the high mast support then slide the mast up the high mast support until the base can be engaged. Put the bolt in. Then raise the mast using another A shape made of 2 spin poles and a tackle to the bow. PM me if you are not familiar with this raisng /lowering method.
I use a 3 purchase tackle on a winch. This means you have plenty of power on the winch but plenty speed when it gets light. I mentioned pull it up as quick as you can. It is all easier with 2 people.
olewill (again)

 

[davidpbo]

Sorry for your bad luck, hopefully the bracket can be repaired or replaced without too much hassle.

We take a lot of care to make sure our mast can't move when being lifted. It is 10m long and of quite a heavy section.

I use ratchet straps attached to the mast as high as I can reach at one end and a pivot point in line with the pivot point of the mast at the other, to make sure the mast cannot deviate too much from side to side. The mast is 2m off the transom before we even start raising.

We use a pulley block to the samson post fed back to a winch to get sufficient control as the means of raising, this is attached at the other end to a scaff pole which is temporarily attached to the front of the mast as close to the pivot point as possible. The end away from the mast also has two ratchet straps attached going back to the same point as the two steadying the mast to stop the stand off pole from wandering too far. If you want more info I will provide it.

 

[Eygthene]

The design of your mast step and heel plug fitting sounds very similar to mine. My mast was made by Z spars (there is a very faded orange logo transfer with a big Z on the mast).

Z spars (sales@zsparsuk.com tel 01473 872354) were very helpful and supplied a new heel plug for my mast which was at least 20 years old.

John

 

[alandav123]

Thanks to everyone for your helpful replies.

I am going round a few places tomorrow that weld aluminium and see if its repairable, it should be.

Thanks again.
I think the boat being so light and easy to rock from side to side made this an accident waiting to happen.

God only knows why I didnt think about putting the mast up before floating her, I was really keen to get her in the water as we have no storage facilities to speak of.

Regards Alan