Mast reinforcement and GRP repair.

[Graeme Shimwell]

New year's greetings one and all.

Panacea annual improvements continue this year and two of the items on the
list I'd like to get some opinions on if you'd be so kind.

Firstly, reinforcement to mast step.

I have drawn a template to laser cut some 5mm stainless steel (see the
attached pdf). I'd love to hear thoughts on whether there is value in
having the two tabs on either side. Also, being inside the boat would I
get away with 304 rather than 316? About a £170.00 difference in price
between the two grades! If I don't have the tabs the cost will reduce some
more.

Second item. Please see the pictures. My hull was damaged in a grounding
by a previous owner. The hull repair was pretty poor and I have been
getting a very small amount of sea water in my bilges. I could not work
out where it was coming from so when the boat was out of the water I filled
the bilges with water and found I had a permanent wet patch just above the
rudder base on the port side. I set to with sanding the area down and
basically ended up with a hole in the boat! So, a bit of GRP work is
required and the main question is this. All indication from stuff I've
read says that I should chamfer the area around the hole to around 12 or
14:1. The GRP in this section of hull is approx. 8mm thick therefore I
should chamfer the area around the hole to about 100mm. My problem is that
I only have 50mm between the rudder socket and the hole. Will 50mm be
enough overlap in this area. It is a very strong area being so close to
the trailing edge of the keel. Any suggestions?

I'd love to hear your thoughts on all of this.

I hope every bodies preparation for a new sailing season is going well and
according to plan.

Kind Regards

Graeme
Panacea
V1479


[Non-text portions of this message have been removed]

 

[alaskaflyfish]

I used mast reinforcement plates on both sides of my step with (10) 1/2" thru bolts mating them together. I also reinforced the bulkheads with stringes and plywood plates at the foot. Inside the boat 304 stainless would be fine. As far as your FRP repair, not every situation is perfect so do what you can. You can taper the hole on the inside of the boat as well as the outside to give you more taper area.

 

[graemeshim]

Thank you Tim for your input.What guage plate did you use on each side of the beam? My beam has not deflected as yet, it's more of a stitch in time as I'm hope to do a few miles over the next few years.Again thank you.Graeme Panacea V1479

 

[alaskaflyfish]

On the forward face I used Steve Birch's 1/4" stainless steel plate and on the aft face I made an exact copy of forward plate using 5/16" 6061T6 aluminum. I epoxy primed the aluminum backsides and holes where the s/s bolts pass thru. I had previously attached pictures in the photo album of the mods, should still be there. I did all this for purposes of preventative maintenance, there were no signs of failure. A stitch in time...etc. The pics should be next to my homemade composting head in the photo album, check it out....Cheers

 

[Vega1447]

Maybe of interest to some that I also installed Steve's ss plate
- a year later I also doubled up the thickness of the mast support
beam.

A year or two later I found that one of the original load bearing
bulkheads was buckling slightly (starboard top right) probably due
to rig tension.
I had boatyard double up the thickness of bulkheads and bolt
through. Also diagonal struts bearing on underwater hull.
As Tim said, "a stitch in time" - I was able to put a little
pre-bend in the mast with no noticeable effect on the bulkheads. I
haven't had to retension in 6 months which suggests that the
bulkheads are sound.
(I posted pics at the time on this forum.)
John V1447 Breakaway


On 09/01/18 21:55, Tim Malone
alaskaflyfish@... [AlbinVega] wrote:

 

[graemeshim]

JohnThank you for your input. I think I will keep the tabs on my beam support from what you and Tim have said. I will look at doubling up the bulk heads next year. Do you think the tabs would get in the way of doubling up the bulk heads?Putting struts in on the starboard side seems straightforward however on the port side the lockers will need taking out I presume and the installing again around the struts.Again thank you for the input.Regards Graeme Panacea V1479

 

[Vega1447]

Hi Graeme.
I contracted the work to my local boatyard but monitored the work
*very* closely.
I had:
A good mechanic - not technically complex work but needed to be
done right.
Top quality marine ply, I paid about €250 for a sheet of (?) 5ft
by 8 ft top grade Lloyds certified 6mm marine ply - no voids...


Comments:

The woodwork aft of the original bulkheads had to be rebated
about 6mm (maybe a little more) as the new ply was glued &
through bolted to the aft face of the old.
Some minor work needed to re secure the saloon bunks and shelving
to the new aft face of the bulkhead, easy as far as I recall.
Good news, the lockers and shelves didn\'t need to be removed.
The diagonal struts were not a major job though the mechanic
spoke (to my unneeded alarm) of "encouraging" the lower bearing
ends of the struts into place with wooden mallets. (I hope that
they were mallets not steel hammers...) To be fair no signs of
striking damage on the inner hull.

Great not to have to worry about bulkhead buckling - the strength
of the bulkheads (I am told) increases as the square of the
thickness - fingers crossed.

Glad to provide photos and my then work plan "instructions" to
the guy who actually did the work.
All the best,
John


On 11/01/18 11:04, Graeme Shimwell
gnshimwell@... [AlbinVega] wrote:

 

[graemeshim]

Hi John That is very interesting thank you. I was imagining the ply would have been 12mm or there abouts. Fitting it to the aft side certainly would be easier. I don't know why I didn't think of that! I would be very interested to see pictures and any other information you would be happy to let me have.I would be very interested to see how the diagonal struts fit in too.Not sure how sending information works but you could send it to my personal email address gnshimwell@... if that helps.Many thanks for sharing your experiences. It will perhaps save me some worry whether I'm making it strong enough.Kind regards Graeme Panacea V1479

 

[Vega1447]

Hi Graeme,
re thickness you are right of course. 12 mm it was.
Some pics here:

Dropbox

www.dropbox.com

On 11/01/18 22:34, Graeme Shimwell
gnshimwell@... [AlbinVega] wrote:

 

[graemeshim]

Hi JohnInteresting pictures. Do you find the diagonal struts get in the way when laying in the berths or are they outboard enough not to interfere with your noggins?I think I'm going to have to sharpen my wood work tooling up!!Many thanks again GraemePanaceaV1479

 

[Vega1447]

No problem at all re sleeping and a second pillow makes reading
when sitting up OK.
The diagonal struts may be overkill but I was determined after a
few years of fussing over sagging beams and bulkheads (and
constantly having to tighten the standing rigging) to get it done
right..
So far so good.
John


On 12/01/18 08:07, Graeme Shimwell
gnshimwell@... [AlbinVega] wrote:

 

[Gazuum]

 To those who used the Ballenger hinge with the wiring running thru the center, have you had any problems with water ingress? Alaskaflyfish, What paint did you use on your non skid? Thanks Gordon

 

[alaskaflyfish]

The Ballenger hinge is the best I could find on the market. I have had water leak thru the hole I drilled in the center but it is very light. Water only comes from the top of the mast where the halyard pulleys are and flows thru the center. The old mast plate did the same thing. It has to rain mighty hard and sideways before water drips come thru, and only very little at that. I did pour thickened epoxy thru the mast foot center hole to coat and waterproof the mast support beam (from the top) before I installed the Ballenger hinge. The bottom plate of the mast hinge is bedded with Maine Sails' Bed-It butyl rubber tape, as is everything on my deck. Good stuff. As far as the non-skid, it was already painted on when I got the Vega. I don't know what it is. It is very thick and seems to have tiny rubber pellets encapsulated in it. When I painted the deck and topsides I just sanded and painted around the existing non-skid.. It has held up really well. I hear people talking about Kiwi-grip and are very satisfied with the results.

 

[Gazuum]

Thank you Tim
g

On 1/27/2018 8:40 PM, Tim Malone
alaskaflyfish@... [AlbinVega] wrote: