Mast Step
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Yep, it looks like we have been racing Spar Wars like we should be doing. A bit of ‘wear’ going on at the stringer supporting the mast. Nothing major, but will plan a fix next year before launch.
The ‘plank’ is sinking a little bit at the mast. The stringer looks like it has been hammered a bit in the shape of the plank and is now about a 1/4″ shorter.
I’m aware of jock straps and beams, but this is a necessary fix regardless AND I want to make the stringer more resistant to compression first.
Anyone done a cut into this stringer? Looking for advice on repair. I don’t believe a layer of glass will be a long term solution. I was thinking along the lines of an aluminum or ss plate or a layer or two of carbon.
Advice out there? I’m sure this isn’t the first fix.
Thanks All!
Bruce,
On Fast Company we added three 1x Ipe to each side of the cross piece and glued them all together. Then replaced the plank w 5/4 Ipe. Ipe is heavy but very dense and will not rot.Old School has an aluminum plate that sits on the bottom of the sump and is bolted through the stringer, acting as a compression post. It seems to work, but I have not taken the time to measure if the base is still where it is supposed to be. I believe the base is supposed to be 48″ from the bottom of the deck.
If I remember correctly, Ron Moore has a kit for rebuilding the stringer. Cut out the old one and laminate in the new. Supposed to be pretty easy, although I don’t know anyone who has done it.
It’s not bad enough to cut out. It needs cosmetics or you wouldn’t even notice. Goal is to solve it. Rules look like you can’t build across the stringer..say with an SS channel over the stringer..correct? The basic problem seems to be that all the stringers are not sharing the load. Spreading load across the one stringer would help. Then use a SS ‘plank’ to make a T or cross over the three(?) stringers. Added weight is not an issue when the mast is getting shorter…LOL
Pictures of ‘fixes’ would be nice!
The beam and jock straps seem to be “the fix” for this from an engineering standpoint. Snug up the straps tight and you should be able (theoretically) to suspend the bottom of the mast in midair without any styringer at all. I had the same issue and decided to fix the cause and leave the hidden cosmetics alone. Of course, my boat is a low budget beater and YMMV.
Don’t have a picture of the repair (at the moment) – but here’s the old stringer after we took it out – Ugly or what?
Repair was simple – had a wood working shop make up a new stringer 2 times as wide out of birch (Mahogany was recommended but I cheaped out) and epoxied/glassed it back in. After 4 seasons, it’s still holding up well. Installed BOD/Jockstraps at the same time, so less stress on it now.
We’ve had a lot of problems with moisture in the other stringers as well – drilling some holes, drying things out over the winter and refilling with thickened epoxy…
Wow..that is ugly. Only 1/4 inch? So that gives me a great idea how much glass is there…almost all of it! I can see it was crushing…and wet. It was plywood, right?
On a separate note..I have a couple of ‘classic’ ‘Surfline’ genoa lead blocks on ebay. Should have offered them here. Search Schaefer lead block
Want to make your boat ‘stock’? LOL
Not plywood – looked more like a 2×4 of some unknown wood. When we took it out – it was pretty mushy. It was compressed close to an inch. Here’s a top view.
Totally different perspective. Now that give me more encouragement to remove the whole stringer and replace as you did. Just need something that won’t compress/rot. The IPE idea is making sense. Or a piece of alum/ss channel over the top of the wood. I always thought of wood as being a mold to shape the FG. But to support a mast compression, it is asking too much of the glass & wood only 3-4″ wide.
Thanks!
I have always thought that placing a piece of channel over the existing stringer would work, but then do you rout a groove into the floorboard and plank to compensate for the thickness? I have seen a couple of boats that have been modified to spread the load over a couple of stringers, and they always seemed overkill, particularly when the actual load point is directly over the first stringer.
The straps are on my list for next spring.
Look at Pride Marines mast step plate with tangs for a picture of Fast Company’s repair.
(http://www.pridemarine.com/index.cfm?category=10007|10326&product=8435054&code=Olson%2030%20Mast%20Step%20Plate)
We did not glass it in place. Just epoxy bogg and screws. Three years in Hawaii so far w/o any issues and we do tend to push it out here.
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