How to seal front-bottom wall of mast step?

M

MrktGarden

New Member
On the front wall of my mast step, about 1 inch from the bottom, the gelcoat has been worn off by the mast. I was able to repair/seal the bottom of the mast step fairly easily by pouring a thin layer of gelcoat over the bottom and then gluing a metal mast wear plate at the bottom with 5200.

Does anyone have any methods for coating / repairing the bottom walls of the mast step? At present, the wear is not severe but I want to find a way to recoat the wall so to prevent any water leaks from developing in the future.
 
I'll take a stab at it:

get two pieces of 1/2" dowel as worksticks

sand the area to be repaired with P40, vacuum out the dust and wipe it out with solvent

measure the circumference of the mast hole.

cut a length of fibre glass the width of the repair x the circ. of the hole

wet it out with epoxy resin

wet out the area in the mast hole where the glass will go with resin

wrap the glass tape tidily on one end of a work stick.

using the other stick, unroll the wrapped glass into the inside of the mast hole.

press it in place as best you can (should stick pretty easily), pushing out as many air bubbles as possible.

Done.
 
Chainsaw said:
I'll take a stab at it:

get two pieces of 1/2" dowel as worksticks

sand the area to be repaired with P40, vacuum out the dust and wipe it out with solvent

measure the circumference of the mast hole.

cut a length of fibre glass the width of the repair x the circ. of the hole

wet it out with epoxy resin

wet out the area in the mast hole where the glass will go with resin

wrap the glass tape tidily on one end of a work stick.

using the other stick, unroll the wrapped glass into the inside of the mast hole.

press it in place as best you can (should stick pretty easily), pushing out as many air bubbles as possible.

Done.
Click to expand...

Bad Idea:
- you have a big chance that the mast will not fit any longer!
- It is illegal

Better Idea:
- buy some of the 1 mm teflon tape that you can warp around the mast, to prevent wear. APS has this stuff. You tape it aound the mast at two places. It comes with instructions and is class legal.

Georg
 
I'd be careful trying to coat the inside wall. There isn't a lot of extra room, and it would be very hard to not leave it lumpy.

Also, the worn gelcoat may have been 1/16" thick or less, and is relatively soft. The GRP wall of the tube is about 1/4" think, and is quite a bit harder than the gelcoat. So, the loss of the gelcoat hasn't weakened the wall at all.

What I'd do is reverse the Lower mast end for end, assuming you have substantial wear, and put a new bottom plug in at the same time. The bottom plug is a little larger than the tube. This should eliminate metal to glass contact, and leave you with plastic to glass contact. After the bottom plug wears some, you can pull the rivet, and rotate it a 1/2 turn.

I haven't found any of the UHMW tapes to work well. Also, there have been threads about putting epoxy in the space between the mast tube and the plywood/GRP base.

Keep the sand out, and that should last a long time.

Al Russell 182797
 
One layer of 6oz boat cloth is 0.55mm thick. If the gelcoat is 1/16th" then fibreglassing it is thinner than the gelcoat. The mast will still fit. Any tape that is self adhesive will tear out on the first use.
 
Chainsaw:
I think that 1/16 inch equals 0.15 mm (I might be wrong, inches and metric system conversions always confuse me).
Nevertheless: In an ideal situation your idea COULD work. However, you are working in a tube, which is far from ideal. My hands are even too big to get in there. It is almost impossible to get it right, and whatever you screw up in there is very VERY hard to correct.
I bought the tape form APS two years ago. To my own big surprise: it is still on there. The key is to clean the mast well before applying it and to have absolutely no overlap.
I also agree with most of Al's comments. Keeping out the sand and other dirt is crucial.
G
 
Thanks for all of your replies. The attached pdf document in the second picture shows (not clearly but to a certain extent) the area where the gelcoat has been rubbed off by the bottom of the mast. I had a teflon strip ahered around the bottom of the mast but I think on one of my masts the edges of the strip flared out and that may have caused the wearing on the gelcoat.

I think the photo shows that the worn part is not deep or large in area. It does not appear that the mast has yet cut into the fiberglass. So, is the best way to seal this exposed area is to try and apply fiberglass cloth over this area?
 

Attachments

  • Worn_Laser_Mast_Well.pdf
    126.9 KB · Views: 160
How old is the boat in question ? From the pics, it looks fairly new. The reason for asking deals with the fact you already glued in a SS disc, when one might have already been in place (the plate is located under the gelcoat, so it's normal to wear off the gelcoat on the bottom of the tube w/o any problems later.

The pic shows what I would call very minor wear of the gelcoat down on the wall of the tube - Your guess about the glued on anti-wear strip causing the wear sounds right - when one of the edges of lifts, it does a good job of abrading down the gelcoat (so much for the "anti-wear" moniker)

The wear is so minor, I would recommend doing nothing, other then making sure the wear strip is removed. It will take heaps more wear into the glass laminate itself before you need to worry about any sort of water penetration. Keep the mast and tube free of sand, dirt etc and you will get years and years of service before you have to worry about reinforcing the step area. When that time comes, it's always easier to repair leaks on the wall of the tube and reinforce the tube from the outside of the tube (inside the hull)
 
My boat is OQTH72192003 which I understand makes it a 2003. I added the steel disc at the bottom of the mast well before I became aware in the forums of the mast step issues. I have sailed to many spongy boats and I just wanted to make sure my boat stayed dry. However, I hope I did not make my boat illegal now. Do you know, from the class rules, what the depth of the mast well has to be?
 
I don't think there is a specific rule/measurement on depth of the mast step, you can check the rules here.
http://www.laserinternational.org/rules/ilcarule.htm I think mast depth issues would fall under Rule 2 where they take 10 random boats to measure..

IIRC, 14" is the avg depth on Vanguard boats, try searching the threads here, use "14 tube depth" as the search term.
 
Section 19 of the 2007 Laser Class Rules describe that a tube or collar can be inserted into the mast step to prevent abrasion of the mast step. Section 19 is repeated below. Has anyone used a tube or collar like this?

19. MAST(a)​
​
​
​
To prevent abrasion of the mast step, a tube or collar of uniform thickness not exceeding 1 mm may be placed around the entire circumference of the lower mast or the mast step cavity. The tube or collar shall not extend more than 10 mm above deck level. In addition, a disc of uniform thickness not exceeding 1mm in thickness may be placed in the bottom of the mast step.(b) The mast or mast cavity may be lubricated.(c) Tape or other bushing material may be applied to both the plastic end cap, the collar of the upper mast and the upper mast to ensure a snug fit. The tape or bushing material may only be used on that portion of the plastic parts that actually slide into the lower section and/or between the upper mast and the collar and it shall be a uniform thickness around the circumference. Taping or bushing material above the collar to fair the collar into the mast is prohibited.​

 
49208 said:
The pic shows what I would call very minor wear of the gelcoat down on the wall of the tube - Your guess about the glued on anti-wear strip causing the wear sounds right - when one of the edges of lifts, it does a good job of abrading down the gelcoat (so much for the "anti-wear" moniker)

The wear is so minor, I would recommend doing nothing, other then making sure the wear strip is removed. It will take heaps more wear into the glass laminate itself before you need to worry about any sort of water penetration. Keep the mast and tube free of sand, dirt etc and you will get years and years of service before you have to worry about reinforcing the step area. When that time comes, it's always easier to repair leaks on the wall of the tube and reinforce the tube from the outside of the tube (inside the hull)
Click to expand...


Thanks; the 'don't do anything' approach works for me :)
My mast tube shows the same type of damage as the one in the picture (thanks for posting). Wanting to protect my relatively new boat (and mast step), I installed the wear tape shortly after I had bought the boat, but that turned out to be a bad move. I did surmise that the wear strip had caused the damage, but wasn't sure. Now I am. For the record, no further damage to the mast tube after I removed the tape (about a year ago) and no leakage either (keeping my fingers crossed).
 
Hi

If I were desperate to do something about it I might have a go with gel coat filler. There's no need to add any glass it's only the gelcoat that's damaged. Gelcoat is too runny to use here but gelcoat filler should work.

I'd make a long spatula the right shape to put the filler on and put it on sparingly - it's not the easiest place to rub down.

It can be rubbed down - wrap a strip of abrasive paper around a dowel and staple it where it overlaps. Make it a narrow strip of abrasive paper so you can be very precise about where you're rubbing down.

Try not to get the filler anywhere you don't want it.

On the other hand I might just leave it alone.

Russell
 
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