Broken mast base

[groby]

I am going to try to describe my problem and try a picture later. The fiberglass in the cuddy where the mast sits has broken and is cracked. So, the mast was pumping up and down the fiberglass area. This shouldn't happen because there is support directly under the mast base area. BUT, on my DS II the mast base was mounted just aft of the support post under the cuddy. It seems there was a manufacturing error. So, now I have a problem to fix. If I move the mast base forward to be over the support I would have to move the base forward about 4 inches. By the time it goes through the hole in the roof of the cuddy the mast will have to be leaning back a lot. Does anybody have dimensions from the inside of the cuddy wayy to the front of the mast base I could use as a starting point to see where I am at. If I have to keep the mast base in the same place I will have to make a new support under that area.

[GreenLake]

@groby.

As you correctly note, the fore-and-aft position of the bottom of your mast determines the mast rake. And the mast rake is something that you don't want to change (even a little) for the convenience of mounting the mast. Instead, normally you adjust the mast rake carefully so that the boat performs optimally.

If the fiberglass is cracked (or worse) you need to cut out a section and make a repair. That's not too hard. At that time, you can replace/reposition the support between the cuddy floor and the hull. I take it, that was the mis-located piece you were trying to describe. (I have a DS1 not a DSII and pictures would definitely help me better understand the situation).

Recreating a support should also not be difficult. I'd assume you could shape one from any suitable wood and then coat it on all sides with epoxy.

If your boat sailed well before the damage, you could simply maintain the mast position, or you could try to determine an optimal mast rake from various tuning guides.

[Alan]

My 1980 DSII has a round-section metal mast support in the bilge, between the keelson and the cuddy floor, then a lower mast section on the cuddy floor, passing through a hole in the cuddy roof, and then a hinged mast on top of that. Sounds like yours.

My first thought was to move the mast support post in the bilge aft to align with the mast, complicated though it would be, but:

Here's where the relocation might get tricky: There are two formed fiberglass cuddy floor supports (stringers, if I've got the term right) running crosswise just aft of the mast. If you relocate the lower mast support aft (at the bottom and at the top), and that way keep the mast rake the way it's supposed to be, the stringers will be in the way, and you don't want to cut them. (Unless the problem is that the mast support was located too far forward when the boat was built, in which case you should be able to relocate it aft without cutting the stringers.)

I have photos of the stringers and mast support somewhere, taken through an inspection port, and I'll post them once I find them.

[Alan]

The more I think about it, the more likely it seems that the lower support was located too far forward when the boat was built. It's attached at the bottom by just a glob of fiberglass (someone else on this forum noted the same thing in their DSII), so it would have been an easy mistake to place it four inches or so too far forward.

[groby]

You all have the right idea on my problem. The cuddy floor is actually broken through for about two wide from side to side. Yes the round support was placed too far forward. For those that have a DS II it would be nice to get your measurement from the back of the mast support to the cudd opening along the cuddy floor. This was I could measure mine and verify the mast support was placed correctly and that the tube underneath was misplaced.

I was thinking I could just fiberglass in some additional wood behind the tube. I am also thinking I will have to cut out a portion of the cuddy floor in order to do this right and then have to redo the floor. I have not done any fiberglass repairs like this before so this should be interesting.

Anybody know of someone in Maryland that can help or do this work?

[Roger]

I added a 10 inch inspection port to my cuddy floor to access the area underneath. I added a bilge pump in a glassed in housing down there.

It was more than adequate room to manage my repair. If you want a picture, just e-mail me at roger.conrad 'att" mts.net

[Alan]

I come up with approximately 31-1/2 inches from the aft edge of the mast support post to the forward edge of the inspection ports in the cockpit floor, and about the same measurement from the aft edge of the mast stub in the cuddy to the forward edge of the inspection port. So, in other words, my support post and mast are in vertical alignment.

This is probably the way they're supposed to be, since the vertical alignment of the mast is determined by the placement of the mast hole in the top of the cuddy, and, theoretically, the placement of the support post under the mast is determined by the vertical alignment of the mast.

I started by measuring from the aft edge of the mast, inside the cuddy, to the lower edge of the cuddy opening (26-1/2 inches). Then I realized that wasn't especially useful.

So, I tried another approach. I placed an extended tape measure inside the bilge, through the port-side inspection port in the cockpit floor. Using the centerboard trunk as a support for the body of the tape measure, I managed to place the end of the tape against the base of the mast support on the bottom of the bilge. I used a bicycle mirror and flashlight to see what was going on in there.

The end of the tape measure, sliding along the bilge, was against the glob of fiberglass, so I slipped it slightly forward to align it with the mast support. After a bit of wiggling (and maybe a bit of nautical language), I managed to get a reasonably accurate measurement.

That leaves the question of getting into the bilge. You could cut a hole in the cuddy floor easily enough, but if you did it aft of the mast, you'd want to avoid the crosswise stringers. It also looks as though there may be stringers just forward of the mast - I couldn't quite tell. I'd recommend checking with a flashlight and mirror, or maybe a small digital camera.

Once you've got the stringers located, you might be able to get enough access by installing an 8-inch access port in the cuddy floor. That's my plan, anyway, to allow access for installing a bilge pump.

[Alan]

Aha. Roger's got it. Got to drag by my weary bones to bed, but I'll be emailing tomorrow.

Thanks, Roger.

[GreenLake]

The actual fiberglass work isn't really all that difficult. There are excellent guides available, and many people here have done similar work and can assist with detailed suggestions.
The trick in your case is how to support the fiberglass for the repair of the cuddy floor until it's cured.

Option 1 is to make a patch on top of the damaged section. That would work, but not look great.

Option 2 is to use a temporary support. Some cardboard would work, which you could remove through an inspection port afterward (like the one Roger suggested). Wax paper would make a good release layer.

For the other aspects of the fiberglass repair technique, get the repair guide from the West System guide, or the "Epoxy book" from the System Three site.

These are both suppliers of epoxy for boat building and repair, and for a repair, epoxy would be the preferred resin (it bonds more strongly to old fiberglass). Their guides are well-written and should help you get up to speed quickly. (The manufacturers instructions as to temperature and mixing ration must be followed with the highest precision you can manage, those are perhaps the most crucial aspects, followed by how to wet out the laminate correctly - but all of these are not inherently difficult to get right).

My personal suggestion would be to find some other small project you can use as a test run to practice your technique. Anything, even a dummy piece of layup would probably result in increased confidence when you do the actual repair.

[groby]

I already have a 6" inspection port just forward of the mast and can see it is definetly not lined up with the support underneath. I am figuring the easiest way to do this is to go ahead and cut out a section of the cuddy floor and go at it. Oh well, just something else to do now.

[GreenLake]

Isn't it fun? Let us know if you want / need suggestions for anything.