Hole in mast base doesn't align with deck plate?

[Happy Camper]

I am getting ready to launch my 240 for the first time (for me!)
Yesterday I stepped the mast and put up the sails in the driveway. Everything went pretty good, but one problem came up as I was going through the process.

When I lifted the mast from it's "nest" in the bow rail, slid it back through the mast crutch and set it nicely down in the mast base plate; the hole in the casting at the base of the mast doesn't line up with the hole in the stainless steel mast base bracket that is fastened to the deck. In fact, it misses the hole by about 1/2"! It appears like the mast is 1/2" too long. There appears to be evidence of many previous mast raising attempts as well. (the stainless bracket and the screw heads are all chewed up from other people using pry bars to align the holes)

I had to use a pry bar to force the mast aft until the holes aligned. I can't imagine that is normal. Any ideas about what might be going on there. The boat appears to be excessively stock. The guy I bought it from has taken excellent care of her. He mentioned it was like that for him as well.

 

[Rick Macdonald]

I can't picture what you're describing. Can't you slide the mast back another 1/2" on the crutch to align the holes for the pin?

The mast plate on my H23.5 and my buddy's H26, H270, and 2 H260s have all had cast plates both on the end of the mast and attached to the deck. I wonder if yours has been replaced?

 

[caverun]

My 240 has a stainless base plate on the deck also. I think this was used for some of the 240's (mine is 1998 model, hull #200). Unlike the 23.5, you cannot slide the mast back farther because of the fixed struts that determine the position on the mast base after it moves into position. Fortunately my mast and base line up perfectly. Easiest fix I can see is to remove the base plate, fill old holes and redrill in correct position. Not sure how the base plate is attached- there may be an aluminum plate in the fiberglass that is threaded for the bolts (no nuts below), but not sure. Might need some advice from Crazy Dave on this one... @Crazy Dave Condon

 

[rgranger]

Like Rick Macdonald, I am also having a hard time picturing what you are saying. Is it that your rigging is tight and won't let you slide the mast back far enough to line up the holes? If that is the case, see if one of the shroud turn buckles can be pivoted aft to give you a little more slack in the rigging. But then be careful as you raise the mast and make sure the burn buckle pivots up with the mast or you will bend the turn buckle. Been there... done that.

 

[Rick Macdonald]

Hard to visualize this!

Caverun, it sounds like you're saying the fixed mast struts are attached before the mast pin is inserted?

 

[Happy Camper]

I think Caverun has figured out what I am (feebly) trying to explain. This occurs when the mast is still resting in the crutch on the aft end, and the mast base is resting on the deck at the mounting plate (before raising the mast) All lines and shrouds are loose at his point. The only physical reason the holes don't line up is that the fixed struts are too short, the mounting holes for the fixed struts were drilled in the wrong place, or the lower strut brackets are not in the correct location. It is a simple triangle. If others are not having this issue, the only thing I can think of is that something on this particular boat has been modified, or built incorrectly. Hmmm, I wonder what was done?
My boat is also a 1998 and has the stainless steel deck plate. Drilling new holes would certainly solve the problem and is likely my solution if I cannot find a "reason" for the miss-alignment.
The deck plate comes off easily with the removal of the four screws. I recently removed the plate to fix a bent tab on the front of the deck plate where the jin pole attaches. I also got a chance to re-bed the plate when I reinstalled it. Nice for my piece of mind!
I think I will have to do a quick check to be sure the mast base casting clears the screw heads if I move the mounting hole forward 1/2". Still, this seems like an odd thing to have to do/fix.
I guess another option would be to remove the mast base casting and cut 1/2" off the base of the mast. Seems like pretty radical surgery. I'm not opposed to doing that if necessary, but I thought I should check in with the knowledge base first.

 

[caverun]

Yes, the fixed mast struts are never disconnected, they rotate from fore to aft as the mast is lifted and moved back to the deck plate. As the mast is moved back out of the bow crutch they rotate up to vertical, and then back down aft of the mast step. And ideally the mast plate and deck plate should line up. The attached photo might help.

 

[Rick Macdonald]

I see! I gather the length of the struts is not adjustable? For example, if they incorporated a turnbuckle or similar.

Comparing a line drawn from the two strut attachment points across the deck plate for these two boats might prove if the plate (or struts?) is misplaced or if the struts are too short.

I doubt I'm being helpful but I find this very curious and interesting.

 

[caverun]

If you didn't want to re-drill, another option (if there is room on the deck plate) might be to elongate the holes into slots to allow necessary adjustment.

 

[Dennis Kitchen]

HC,
Something was made wrong or "remade" wrong for sure. When your mast is standing are your fixed struts under a lot of tension? It could be that the struts were drilled at the wrong length or more likely is that your step has been modified. Google US spar and look up your boat model and year to see what should have been there..

 

[Happy Camper]

The base bracket does not look like the one on the US spar web site for my boat, however, mine looks just like the one on the picture caverun posted. I think it's a stock base. As far as the tension in the struts goes, I can't tell by looking, but I (and others before me!) had to pry pretty hard on the mast base plate to get the holes to line up. It had to move almost a 1/2"! There must be some pretty big tension on them. I will check tonight to see if the tops of the brackets where they attach to the mast appear to be bent in any way. If they were, this could cause the issue. I will report back!

 

[Crazy Dave Condon]

Caverun
Happy camper hit upon what may be a problem here but I need some additional information. Send me a private email with your phone number. I will call. In the meantime. I need some measurements. First measure from center to center the attachment of the bolts for both struts and then measure from the base of the mast to the center of the holes where the bolt attachment of the struts are on the mast. I am trying to see if those two measurements are the same lengths.
I was aware there was no adjustment for the struts but later rectified due to my recommendation. I will call. Just include your number. Are you bringing the boat home anytime soon?

Currently I am working on Kermit boat here due to lightning strike. Even had lunch yesterday with a new owner of a 170 and went over the boat in detail.

Dave

 

[Happy Camper]

OK, I did a bit of digging around last night to verify my original thoughts. What I suspected was that the side strut mounting bracket holes do not line up with the holes in the mast base plate. It's a bit tough to see in the picture, but in theory the four holes should line up on the same axis; they certainly don't! Not too surprising they are off by almost exactly the same amount as the mis-alignment of the mast base hole to the deck plate. I have no idea why it would be like that, or if it was just that way from the factory. Now, what to do to fix it.
I will send you info Dave, thank's.
More fun to follow.

 

[rgranger]

Happy Camper

Can you disconnect the struts from the deck, put the mast base in place and then see where the strut attachments hit the deck. Seems like that is where the strut attachments should have been made. Mark that. Then fix it right.

??????

 

[Dennis Kitchen]

HC,
I think you're on to something now. Perhaps CD already knows of a fix. Be careful if you try to raise the mast without the struts. You must be on level ground side-to-side with no wind loads across the beam. Those struts are really only there for mast raising side loads. On the 23.5 we have removable bridle cables, on the 240 Hunter decided to make them permanent struts.

 

[Happy Camper]

That would be the way to set it up originally I think rgranger. The problem is that the bolts that attach the brackets to the deck are either 1/4-20 or 12-24 thread. I'm afraid that if I move them to the correct position, when I drill and tap the new holes, there will be almost no material between the old holes and the new holes.
It's just the wrong amount of "messed up" I think. Hmmmm.
At this point, I am leaning toward removing the mast base deck plate and drilling a new set of holes 1/2" forward of the existing holes. This seems like the least invasive approach and is reversible as well. If I don't like it, I can just go back to using the original holes.

 

[caverun]

That's the same mast base plate my '98 240 has. I forgot about that cut-out in the deck plate for the centerboard uphaul... if you move the plate will that be off too much and bind on the line?

 

[Rick Macdonald]

Moving the mast plate looks messy too, due to the ground wire and uphaul holes. Could the mast plate or strut brackets be refabricated using the same deck holes but with the other holes lined up? Or, somehow modify the struts to be adjustable? As they are now, I think the struts would be under less tension when the mast is raised because the mast pin is aft of the strut brackets. Making the struts longer could end up with the struts under compression load when the mast is raised.

 

[rgranger]

That would be the way to set it up originally I think rgranger. The problem is that the bolts that attach the brackets to the deck are either 1/4-20 or 12-24 thread. I'm afraid that if I move them to the correct position, when I drill and tap the new holes, there will be almost no material between the old holes and the new holes.
It's just the wrong amount of "messed up" I think. Hmmmm.
At this point, I am leaning toward removing the mast base deck plate and drilling a new set of holes 1/2" forward of the existing holes. This seems like the least invasive approach and is reversible as well. If I don't like it, I can just go back to using the original holes.

It's just the wrong amount of "messed up"

That is funny. I'll have to borrow that one.

What if you drilled out the old holes a bit to expose solid material. Then filled them with fiberglass reinforced epoxy. Let that set. Then drill out your new holes in the right place. Are you through bolting? If so, then just enlarge the backing plate and you should be okay.

 

[rgranger]

I would worry that moving the mast plate will mess up all of your standing rigging... then you would need to lengthen and/or shorten stays and shrouds etc. And how would that effect where your jib blocks are relative to the angle of your head sail etc. I would fear that moving the mast will cause enough other problems that you won't see water this summer.