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Old 11-06-2011
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Optimum stand placement for boats stored on the hard

I posted this over on the Catalina 25/250 forum. It would be interesting to hear you guys debate it:

I thought it would be interesting to discuss the optimum placement of stands for offseason storage of the C250WK. I'm putting this message into the General section because it may be of interest to C25 owners also, even though the specifics may be unique to the C250WK model.

Here's a pic of my boat in early 2010, before I purchased her:


Here is a diagram of the placement of the boat stands in this pic. Note that stands #3 and 4 are placed just in front of the keel. I surveyed stand placement for number of other C250s at Winters Sailing Center, (huge Catalina dealer in NJ), and they were all placed similarly:


One year ago when we moved the boat to land after our first season of ownership, we initially had the stands placed in that manner. But while leveling the boat, I noticed that once she sets on her keel, the entire remaining weight is borne by stands #1 and 2. In other words, in the absence of wind and/or weight shifts caused by someone walking toward the bow, the boat would stand entirely on a tripod formed by the keel and stands #1 and 2, without stands 3, 4, or 5. As a result, the sole purpose of stands 3, 4, and 5 is to provide additional secondary support to avoid the effects of wind and load shifts.

In light of this, I became very concerned about having stands 3, 4, and 5 all in front of the keel. With the boat's center of mass located behind the keel, I believe that stands 3 and 4 would offer stronger support behind the keel, closer to that center of mass. Therefore, I moved stands 3 and 4 behind the keel as shown here:


Note that this offers several benefits. The key benefit is that these stands now are placed at a position where a sideways force on the boat would push most directly against them. Note also that the boat's beam is broader at this placement, providing the best moment arm to resist falling. And also, note that in this case, stands 1, 2, 3, and 4 are all along interior bulkheads, thus minimizing the flexing of the fiberglass.

I did this last winter with a successful result, and just did this again today. My greatest reluctance was that it differs from Winters' placement, and since they're a big dealer they must know what they are doing. But I still cannot see any reason to place the stands the way they do.

What do you guys think?

DISCLAIMER: If you like my idea and decide to set up your stands similar to mine, you DO SO AT YOUR OWN RISK. I accept responsibility for my own boat, but I will not accept responsibility for yours.

And, just as a reminder, the goal here is to avoid ending up like this guy in another boat yard up the road from me:

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1998 Catalina 250WK Take Five (at Anchorage Marina, Essington, on the Delaware River)
1991 15' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)
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Old 11-06-2011
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A couple of other things.

Although I did not mention it, chaining the opposing stands together is essential. Doing so makes them act much more like a cradle would. Plywood under the legs is also important to prevent settling into the ground and rust from ground moisture.

Five stands, properly placed, is perfectly adequate for a 25 foot boat. I've never seen a yard use more for a boat this size. I had to buy my own stands (boat club rules), so I researched this carefully to ensure I was neither skimping or wasting money.

The boat that fell over appeared to be due to a several errors. There were insufficient stands - only 4 for a 28-30' boat, with nothing on the bow. They appeared to be over-extended (too small, and compensated by cranking the stands up too high). The keel was resting on a stack of cinderblocks - you can see that the stack fell in the opposite direction from the mast, so there was clearly a pivot around the stands. And the boat was stored perpendicular to the prevailing wind off the river. This is supposedly a "professional" yard that provides the stands and the manpower to secure the boat. I nearly used them before I decided to join the boat club. I'm glad I didn't.

I think it's a very good idea to drop the mast for boats of our size. It reduces windage and is relatively easy to do.

Finally, here's a pic where I added the triangle to show the load bearing tripod. It's pretty easy to visualize why it's better to have the stands behind the keel instead of in front:

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Formerly posted as "RhythmDoctor"
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1991 15' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)
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Old 11-06-2011
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Best critique of my thinking so far:

Quote:
Originally posted by Steve Milby
I think the flaw in your thinking regarding placement of jackstands is that weight distribution isn't the only concern. You also need to think about windage, and resistance to the wind. If jackstands 3 & 4 are placed aft of the keel, then jackstand 1 will prevent the bow from drooping, but it will provide almost no lateral resistance to the wind. In a strong wind, with no lateral resistance forward of the keel, the bow could rotate to leeward, twisting it off its jackstands. If jackstands 3 & 4 are placed forward of the keel, they will provide lateral resistance to any lateral movement forward of the keel. I've never seen any marina place jackstands in that manner, and don't think it would be safe in an especially strong wind.
Best point I've seen yet. Thanks! Something to think about (for a few days), and eventually to act on before the winds pick up. The middle pads are easy to relocate because they do not bear any weight. Fortunately I have trees close by to starboard, so lateral winds are slowed somewhat in my location.

I am not 100% convinced by your argument (I'm stubborn that way), but I understand what you are saying and am now 50-50. The really safe decision would be to buy two more stands, but I'm not there yet either.

The trailer comparisions are interesting. However, weight distribution could be very different due to the need to consider acceleration and deceleration at highway speeds. This probably requires a great deal of support in front to keep the boat from moving forward, especially if turning and braking at the same time.
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1998 Catalina 250WK Take Five (at Anchorage Marina, Essington, on the Delaware River)
1991 15' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)
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Old 11-07-2011
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My yacht club stores member's boats in our parking lots. The club requires 7 stands for all boats, even 25 footers. The extra pair provides redundancy. You basically have two pair supporting the stern section, and a pair plus the forward one supporting the bow section.

Last edited by JimsCAL; 11-08-2011 at 08:39 AM.
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Old 11-07-2011
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Hauled out on Saturday also, at high tide.

Five stands and sitting on wood blocks. I check the stands throughout the winter as I am at a low point in the yard that floods a few inches at high high tides.



Fox Grove will have pulled all boats by the end of this high tide cycle probably with the last high about 3:00 PM mid week.
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Old 11-07-2011
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Even my J24 trailer has six stands to balance and support the boat as when bouncing down the road on a small trailer using the keel for the full load is not the same as a static boat on the hard

The most BS thing i see is half rotted keel blocking



Every boat that gets moved around here spends some time on three stands which is always a bit hard on the mind



You cant move stands around to do bottom work without a set of seven anyway
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If a dirty bottom slows you down what do you think it does to your boat
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Old 11-07-2011
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Jackstands are not put in place to support the boat. The keel does that. The stands are there to keep the boat upright, over the keel. Yards usually place them where the force they exert will be spread as much as possible, to avoid them deforming the hull. The original positions indicated by the Dr. would seem to have them under the main bulkhead that supports the mast, though this particular design may not have that feature. It is usually the best place, structurally, to support and spread the loads involved. The hull, bulkhead, and cabin are all already reinforced there to support the stresses from the mast. These reinforcements spread the pressure of the jackstands as well. The area at the end of the bunks/galley usually only has a partial bulkhead, and the deck and cabin are not subject to extra stress from the mast, so are not reinforced. Though the fear could be misplaced, I would worry about deformation of the hull from putting the stands in the "new" positions. Our boat is larger, and the stands (seven in all) go at the bow, the main bulkhead (mast), the aft bulkhead (galley) and another set aft, under the cockpit.
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Old 11-07-2011
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Quote:
Originally Posted by paulk View Post
Jackstands are not put in place to support the boat. The keel does that. The stands are there to keep the boat upright, over the keel...
I am aware of that, and thought I made that pretty clear.
Quote:
Originally Posted by paulk View Post
...The original positions indicated by the Dr. would seem to have them under the main bulkhead that supports the mast, though this particular design may not have that feature. It is usually the best place, structurally, to support and spread the loads involved. The hull, bulkhead, and cabin are all already reinforced there to support the stresses from the mast. These reinforcements spread the pressure of the jackstands as well. The area at the end of the bunks/galley usually only has a partial bulkhead, and the deck and cabin are not subject to extra stress from the mast, so are not reinforced. Though the fear could be misplaced, I would worry about deformation of the hull from putting the stands in the "new" positions....
This boat is different. There is no forward bulkhead. The downward force of the deck stepped mast is transmitted to the keel via a compression post. The upward force of the shrouds is transmitted through the cabin top to the hull via rods that extend through cabintop chainplates that connect to the rods. So unlike most boats, there is no forward bulkhead for the chainplates to attach to. I have confirmed the lack of bulkheads with a stud finder along the outside of the hull.

As you can see in the picture, there are bulkheads to port on the front and back of the head, and between the aft berth and the battery compartment in the stern. From the standpoint of avoiding "oilcanning," all three of these locations are better than anything forward of the keel.

However, I am considering moving the stands forward of the keel for a couple of reasons, not the least of which is that I added 300 lb of ballast to the bow last season, so the boat may now be quite a bit less stern heavy than it was last winter. It is quite possible that once I've removed the outboard and battery from the stern, when I walk forward on the bow, the boat may become bow-heavy and need the side support in front of the keel to avoid lifting out of the four stands that are aft of the keel and twisting around the keel.

All of this is making it clear to me why Practical Sailor recommends tying the boat down with auger anchors or (preferably) eye bolts embedded in concrete.
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1998 Catalina 250WK Take Five (at Anchorage Marina, Essington, on the Delaware River)
1991 15' Trophy (Lake Wallenpaupack)
1985 14' Phantom (Lake Wallenpaupack)

Last edited by TakeFive; 11-07-2011 at 11:57 PM.
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