Compromised Mast Step on an Irwin 43?

[F15EWSO]

I'm looking at an Irwin 43 center cockpit that appears to have some compromised wood in a lateral stringer near the front cabin/head. A limber hole was drilled through the stringer just to starboard of the mast box to run a fresh-water hose underneath the sole. When they drilled they threaded the hose right through the limber hole and never sealed the wood/plywood. Since then the wood has absorbed water and part of the stringer "rings" dead with a hammer.

Access there is a bear, the surveyor and I are uncertain if the lateral stringer we see forward of the mast box is integral in the support of the mast or if it just mated or "sistered" up to the actual box/step that is the true support for the mast. The stringer could just support the molded plastic floor and the mast step/box is not really part of the compromised wood. There is a house bank battery tray in the way, we peeked in all the areas we could see but just can't tell if the stringers are "weight bearing" or if the mast step has its own supports actually beneath the mast itself.

I know this verbal description is a bit weak, what I'm looking for is if anyone has an idea of what the actual construction is like under the mast of this vessel or better yet a diagram or repairs undertaken at one time? If you click on the photo you can see half of the issue. Sorry took this photo previously not expressly for this issue.

This is pretty serious issue and we are not sure how to proceed further with the seller unless he authorizes some invasive investigation!!

Thoughts??

[barnakiel]

I would be surprised if the mast is supported by a box construction where any of the walls (stringers here) were structural. Compression forces there are substantial and so my guess would be that the mast is supported by a solid (block?).

If things look OK otherwise (no compression), I would simply cut out the offending member and replace with a new, properly sealed and laminated element. This should be a self-repair job for any owner. If there is compression, I would lift the the mast prior to repairs.

Upon cutting the thing open you will get a clear idea of how the mast is supported. If the support is a wood element that got saturated with bilge water, the wood will have to be replaced too.

b.

[F15EWSO]

Originally Posted by barnakiel

I would be surprised if the mast is supported by a box construction where any of the walls (stringers here) were structural. Compression forces there are substantial and so my guess would be that the mast is supported by a solid (block?).

If things look OK otherwise (no compression), I would simply cut out the offending member and replace with a new, properly sealed and laminated element. This should be a self-repair job for any owner. If there is compression, I would lift the the mast prior to repairs.

Upon cutting the thing open you will get a clear idea of how the mast is supported. If the support is a wood element that got saturated with bilge water, the wood will have to be replaced too.

b.

Thanks for the inputs Barnakiel,

"I would be surprised if the mast is supported by a box construction where any of the walls (stringers here) were structural. " Agree, it would make no sense to have the space underneath be empty, there should at a minimum be additional cross-members, solid, something beneath the mast, not relying on the "edges" into a stringer.

"Compression forces there are substantial and so my guess would be that the mast is supported by a solid (block?)." Yep

"If things look OK otherwise (no compression), I would simply cut out the offending member and replace with a new, properly sealed and laminated element. This should be a self-repair job for any owner." That's the issue we can't see unless we get permission to cut/drill through a stringer to figure out the type of supporting (if any) under the mast. Hopefully the fix will be as easy as you indicate. Though with the bulkhead, floor, available space it will not be that easy. Rocket Science? Oh heck no! But looks to be a real PITA spot.

"Upon cutting the thing open you will get a clear idea of how the mast is supported. If the support is a wood element that got saturated with bilge water, the wood will have to be replaced too." Yeah this could upset the balance of the agreed offer as getting the mast out will cost; as well as the repair.

THanks again

[Cheechako]

Is this a wood boat? Or are you saying a fiberglass boat has wood box stringers...? Or is the wood just the inside of a glass stringer?

[osirissail]

Look at the bottom of the mast step. Is it a fiberglass base that the mast shoe (part that captures and holds the mast in place)? It is highly likely that the mast is "keel stepped" which means it is sitting on top of the ballast or hull. And does not have any empty space underneath.

From the photo, I would surmise that that particular board is a wall/barrier for boxing in the battery box. If it is possible, see if that particular piece of wood passes through the forward/aft walls to the left and right of the mast step. You may be able to observe the "ends" of that piece of wood which are simply butted up against the forward/aftward beams that form the sides of the battery box and/or sides of the keel step box. So you could simply cut out the rotten board and replace it.

In situations where you expect wood to be exposed to water/sea water, cut and fit the new wood - but then remove it and soak/paint it with thinned epoxy to "waterproof" the piece of wood.

[F15EWSO]

Originally Posted by Cheechako

Is this a wood boat? Or are you saying a fiberglass boat has wood box stringers...? Or is the wood just the inside of a glass stringer?

I believe it is the latter; according to the surveyor the stringers in Irwins are marine plywood that is glassed in. Varying opinions on the use of the plywood vs solid wood, expansion, etc but again according to the surveyor the issue is when the glass is compromised, in this case by the limber hole to pass a fresh-water hose.


The boat is fiberglass.

[F15EWSO]

Originally Posted by osirissail

Look at the bottom of the mast step. Is it a fiberglass base that the mast shoe (part that captures and holds the mast in place)? It is highly likely that the mast is "keel stepped" which means it is sitting on top of the ballast or hull. And does not have any empty space underneath.

From the photo, I would surmise that that particular board is a wall/barrier for boxing in the battery box. If it is possible, see if that particular piece of wood passes through the forward/aft walls to the left and right of the mast step. You may be able to observe the "ends" of that piece of wood which are simply butted up against the forward/aftward beams that form the sides of the battery box and/or sides of the keel step box. So you could simply cut out the rotten board and replace it.

In situations where you expect wood to be exposed to water/sea water, cut and fit the new wood - but then remove it and soak/paint it with thinned epoxy to "waterproof" the piece of wood.

Good advice on "waterproofing" the future repair. I don't know the answers to your initial statements but that is the sort of advice or queries I am seeking so WHEN we do get eyes in there I can sort of cobble all these questions or answers together and form a better opinion. IF in fact it were sitting on the keel then this would be less of an issue. I don't believe that is the case but there may be a block under neath the mast that sits on the keel, again that would be good news.

please keep thoughts or ideas coming.

[Stumble]

I have found a plumbers snake, or any other little camera on a stick invaluable for things like this. You should be able to stick it into the limber hole and look around to see what it going on inside.

Short ones are available from Harbor Freight for I think $40. If not you can find them online for not to much.

[50gulfstar]

My Irwin43`s mast is sitting on the keel area just forward of the battery bank on solid hull over top the keel.I would follow the earlier advice and just cut out the damaged area and replace.I can assure you ,the mast is not supported by a wood stringer.
1986 Irwin43 - Play Date #134
Crisfield,Md.

[F15EWSO]

Originally Posted by 50gulfstar

My Irwin43`s mast is sitting on the keel area just forward of the battery bank on solid hull over top the keel.I would follow the earlier advice and just cut out the damaged area and replace.I can assure you ,the mast is not supported by a wood stringer.
1986 Irwin43 - Play Date #134
Crisfield,Md.

Thanks for the reply,
we are to get acess to it soon and will remove batteries and investigate. Your comments from your boat and model are reassuring.

Cheers

[Fiberglass1Inc]

It might help to get the structural terms correct. A transverse frame in way of the keel and/or mast step is a floor. Stringers run fore and aft. What you are standing on is a cabin sole, not a floor.
Floors reinforce the hull in order to support the keel. So if a floor has a hole that was never sealed it should be repaired so that the keel won't wiggle its way off the hull. As 50gulf said, it's not likely that floor supports the mast.

[adlib2]

Just came across this Post and doubt if F15EWSO is still requiring a response; however, I have owned my Irwin 43 for 17 years with no problems with the Mast Step which is an aluminum shoe with a key that fits into the bottom of the mast for location and the whole sits on the lead keel.
When I first purchased my Irwin I had problems with the Insurance Co. due to the Surveyor reporting rotted wood in the keel step. On investigation I found the rotted wood in question was the Form for constructing the fiber glass keel step box which had been left in and served no on going purpose. I removed it.
The athwart frame forward of the battery box and aft of the mast is to support the two small pieces of removable sole that are contoured to fit around the mast. There are no other loads on it.

Alan.