Rebuilding mast support in a Bristol 29

[ddsailor25]

Originally I thought my mast step needed to be rebuilt but after closer inspection I found that my forward mast compression post is failing. I believe it's the support in the flooring that is giving way. Has anybody done a repair like this and have suggestions?

Thanks,

[David]

Can you provide some pictures? What leads you to believe it's the forward compression post at the juncture of the keel? Typically that is not an area that holds standing water. Last year you said you were going to sister the two upright posts. Did you do that? Did that have any effect?


David

[ddsailor25]

Dave,

Yes last year I did sister up the compression post, but the mast was aready under load. When the mast was unsteped this fall the sistered compression post was no longer in contact with the cabin top. Also, the original support is not in contact with the support ether. Looking under the flooring it's hard to tell how they ran the supports, but there is nothing under the compression post to take the load to the hull or the displacement block.
So, my plan of attack will be to take out the forward compression post and see if I can sure up the supports over the displacement to carry the load. What do you think? I can take some pictures when it gets a little warmer if that will give you a clearer picture.

Dave

[David]

Some pictures of both the top of the head door frame and also under the sole would be helpful. Also some shots of the exterior maststep if you can.

Thanks,

David

[Hirilondë]

You definitely need to take pictures. Your description of the problem is really hard to understand.

That the cabin top lifts off the compression post when the mast is removed means something has moved or rotted. Your post is no longer long enough in effect to carry the load from the mast step to the keel or hull where it was meant to. So now when the mast compresses the cabin top it flexes it down until the load is taken by the now shorter post or the cabin top itself. This could mean the bottom of the post has rotted and is now being squashed down, or that the landing on the bottom of it has moved or rotted. If the step and post where visible is fine, I would venture to guess the problem is the base of the compression post or the bottom of the post itself. Only a thorough inspection of all will tell.

[Capn_Tom]

If I'm understanding your description there is no support beneath the sole at the compression post to transmit the load to the keel. If that is the case you simply need to fabricate a beam for this space, glass it in place in the bilge, and drive in some wedges between the beam and the sole to tighten everything up. If on the other hand I am not understanding your description, I haven't got a clue.

[ddsailor25]

Dave Fennegan

That is what's going on. It's going to we warmer out this weekend so maybe I'll try and get some pictures and or video and post it on youtube. I'll be in touch.

Dave

[ddsailor25]

I posted a video on youtube titled "bristol 29 mast step". After closer inspection I do not believe the problem is at the top of the compression post, but in the floor. Take a look at the video and let me know what you think.

Thanks,
Dave

Ps. Please excuse the boat, she is a mess!!! Also, I got my port and starboard backwards in the video.

[Hirilondë]

Based on your video and commentary I think you have analysed the problem correctly. I don't know the Bristol 29 first hand, but it seems to have an interior fiberglass insert similar to the Renegade. The sole being part of this insert. Either the void under the mast compression post was never properly filled to carry the load and eventually sagged, or the shim moved. Ether way, blocking under the compression post to carry the load directly to the hull seems to be the right course to take.

[David]

Dave,

I checked my boat tonight and it looked similar, except instead of the two spacers that your mast step has, mine has a fiberglassed block. However it is not centered under the compression post. Adding it to the list of projects.

David

[ddsailor25]

Dave,

I'm glad that you found something simular and it can be repaired before your mast step starts to sag.

Dave

[Hirilondë]

LOL, the use of the name Dave is gonna get confusing soon.