H-34 Compression Beam

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Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
Doing the mast compression job.. here is a shot of the inside of the cross beam that the mast rests on.. as you can see, there is no material for taking the mast load directly under the mast.. when the wood on the sides became squishy the glass beam tried to take the load but the forward vertical wall collapsed.. Picture is looking up into the space that the compression post pushed on; looking toward port with forward to right in picture. You can see that the little 1” PVC wire run tube tried to help with the load and cracked from compression. The yellowish glass that ya see in the right side of the hole is the forward vertical edge of the beam that has buckled inward from compression. The post itself is in pretty good shape with only a small spot of rot on the very top. I plan on re-using the post after replacing that spot and heavily treating the boards. Interesting that the ends of the post seem to have been dipped in resin .. there is a thin end cap protecting the end grain of the 2X4’s that make up the beam. The vibrating tool is great for this kind of work! (I destroyed two blades getting through the fiberglass beam!) Will post more in modification page when work progresses.. Thanks Allan Hadad, Fred Ficarra, and Barry Olsen for your excellent pictures ..
http://www.youtube.com/watch?v=JdrSBzy8NwQ&feature=related
 

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Dec 14, 2003
1,393
Hunter 34 Lake of Two Mountains, QC, Can
Hi Claude,
I have a complete .pps with lots of picture of how I did it on my 34. Forward your e-mail address to me at c.l.auger@hotmail.com and I'll send it to you if you want.
Good luck
Claude
 
Oct 14, 2007
64
Hunter 34 Milwaukee
Thanks Claude

I asked Claude to email a copy of his PP Presentation of the post repair on his H34.

He did a fantastic job on both the repair and the documentation.

If/when I need to do this job, I feel prepared after seeing the pictures and Claude's explanations.

Thanks again. It makes owning a boat so much easier with people sharing their knowledge with others.

Al
 
Sep 25, 2008
385
Harpoon 5.2 Honolulu, HI
Kloudie -- I'm actually working on this same project tomorrow on Rogue. I cut in from the main salon on Saturday, then dug out all of the remains of the 2 X 4 that originally ran across. I'd say about a foot of it is gone. I am going to cut small pieces of teak to use as coring, then use fiberglass gel all around it to fill the voids. Hopefully that will displace the load somewhat. I replaced my compression post (used pressure treated wood) last year, but once I put it all together in June, a small crease developed in the inside on the fiberglass right above the compression post. So I knew the top part was gone.
Man, for about $5 more in fiberglass in that beam and probably $50 worth of stainless to use inside the compression post, Hunter could have made this so that it would have never had these problems. Oh well.
I'll try to send pics after I get 'er done tomorrow night!
 
Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Hi guys, I would suggest that you replace the pine compression post with something a little more subtancial (stainless stell or alum). Even if you get water in the post again you will not take a chance of a failure.

We had ours replaced (stainless steel post) on our '85 Hunter 31 and had another problem a little later on (couple of years) It was easy to fix the problem the second time around.

You may be able to find a piece of s.s. tubing from a salvage yard or even a welding shop at a discount.
 
Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
I definitely have to thank Claude Auger now as well. He forwarded me his excellent PowerPoint file with his excellent pictures and notes.. This week I am doing a lot of preparation work and hunting for a suitable piece of scrap aluminum for the beam internal compression part.
 
Oct 14, 2005
2,191
1983 Hunter H34 North East, MD
Claude A, Claude L and Mark...

Thanks for paving the way on this nasty job. I've been lucky so far in working to prevent water penetration at the mast and having this problem occur. With the good documentation you guys are developing I'm sure if and when the time comes I'll have great resources for the cure!
 
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Dec 2, 1999
15,184
Hunter Vision-36 Rio Vista, CA.
Mark: Nothing went wrong with the stainless. We got some more water intrusion but it was a matter of just resealing the drip tube.

The stainless just prevent you from having to replace everything.
 
Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
Finding something interesting.. I only started getting water on the post when the forward edge of the cross beam buckled.. which happened after the wood in the cross beam smushed.. I have a leak in a deck fitting that is leaking into the cross beam and not from the tube.. When the forward edge buckled, it put a lot of load on the little PVC wire trace and cracked it .. at that point, water from the beam could get down to the post.. Guess I'll re-bed and seal the deck mounted fittings in the area..
 
Sep 21, 2009
385
Hunter 34 Comox
A slightly different way of fixing the sinking mast

I have an 85 H34 and have the first signs of this problem. After reading everything on this site about the fix and after talking to the factory about it, I have decided to approach the repair from above instead of below. I really appreciate all of the forensic pictures and work that all of you have done. They allow a person to see what is going on inside the beam. First though, I think that tearing into the beam and digging out all of the wood is a bad idea as it is a major structural component of the boat and I worry that it could weaken it if it is not built back up to the same strength so... I am going to fabricate a 2 in stainless schedule 40 pole with a 3/8 stainless plate the shape of the mast foot (but 1 in. bigger) welded to one end. I will then drill an appropriate size hole(after removing the wiring) through the cabin roof and beam and insert the pole through and down to another 3/8 plate on stringer below. Because of the way the stringer and beam line up...or not, the pole will have to come through on the forward side of the (inside) of the beam to land on the aft half of the stringer. The wiring will be re-channeled through the pipe and holes will be cut where it needs to exit. When I looked closely at the beam where it is starting to "wrinkle" from the pressure on the cabin roof, it was clear that there was more pressure on the aft side than the forward side and all of your great pictures confirmed that the existing post was only supporting the forward half of the mast, so over time as the main sail is pulled down hard the mast had more pressure aft causing it to fail here first. In measuring things out it is clear that the mast sits center on the beam and needs support the full width of the beam so to ensure this, there will be a gusset welded to the top plate and pipe to give it the required support. This method of repair should result in minimal destruction and will take the mast downward load completely away from the cabin roof and transfer it to the stringer(which is also full of wood) where it should be. As well there will be a collar and plate installed on the new post that will support the beam from below. So, if you have your spin saw in hand and ready to cut big holes in the beam you might want to hold off a bit and see how this turns out for me. I plan to have it finished in a month if all goes well. I have a drawing or two on my laptop and could post them on request. If anyone out there has any comments please feel free.
 
Sep 25, 2008
385
Harpoon 5.2 Honolulu, HI
Heart of Gold -- that sounds like a very well thought out and permanent solution!

I fixed mine yesterday -- actually cut in from the main salon side. Dug out all of the smooshy wood, then filled back in with large blocks of teak, and filling voids above, below and between pieces with fiberglass gel. I will make a small wood cover to go over the hole I cut. It was a little hard to get to this way, but I didn't like the idea of cutting in from the bottom.
The old beam in mine was pretty much mush for about six inches on either side of the mast. Mine was starting to crease a little in the salon side, but I also did set my rigging up a little looser than it should have been after I noticed the crease. I launch again in about a month and we'll see how it works out. I think the material I have put in should be more than enough do the job.
 
Nov 6, 2006
9,884
Hunter 34 Mandeville Louisiana
Heart of Gold.. couple of things you might want to consider.. First, if you look at the picture I posted, the void is forward of the wire run, not aft. The forward vertical edge of the fiberglass cross beam is what collapsed on my 34..Next, Allen reported that underneath the mast step is: a, deck fiberglass, b, ¼” aluminum plate, c, ¾” solid synthetic core material, and d, another layer of glass.. before you get to the compressed wood residue.. Ya might want to think carefully about disturbing that piece of layup from the top.. there is nothing in there that will rot until ya get to the wood, and that is easier to deal with from below. My job is progressing slowly, I carved a couple of oak implants for the rotted spot in the top of the compression post, the post is treated now with copper napthenate, and I have located a 2” thick piece of aluminum, suitable for bedding inside the beam, up under the mast step..
 
Sep 21, 2009
385
Hunter 34 Comox
Kloudie, Thanks for your comments, much appreciated, The Aluminum embedded in the deck is what I hope to drill and tap to anchor my Stainless plate to from the top. The mast step will bolt to the plate and perhaps the original holes as well. It is pretty clear that even though the original construction was pretty beefy as far as the glass layup was concerned, this wood in the beam was a bad idea. Aparantly the mast under full load will exert the boats own weight, for the H34 thats 12000lbs! It is interesting that yours is failing forward and mine aft. When I scoped this out with a fiber optic camera, I coud see voids forward and aft of the wood. It is almost as if it was an afterthought and the factory quickly added what ever they had on hand to keep the line moving. The method that I am using was actually suggested by Hunter as "that is the way they build them now" and the more I thought about it the more sense it made. I will be boring through the layers with my trusty hole saw and should have no glass repairs when finished. Cheers
 
Oct 14, 2007
64
Hunter 34 Milwaukee
Please post all pictures and methods

Heart of Gold,

Please post all drawings and pictures of the project that you can. The more we get to look at the problems with our boats the more informed we can be about the repair method to choose.

I'm sure we all have varied ideas on how to accomplish our goals. It really helps all of us in the long run.

Al
 
Sep 21, 2009
385
Hunter 34 Comox
Just thought I'd let you all know how my repair is going....and it is going as planned. The mast is off, the old post removed, wiring pulled out of the way, 2.5 in hole drilled through the roof, and new post fabricated and fit tested. I should be finished the initial install with mast re stepped late next week. Couple of things I've found, it really helps to have a machinist with stainless fab. experience as a neighbor(next slip) and it would be really nice to do this when it is sunny. While the mast is off, I couldn't help but try to pull the chainplate rods. Much to my surprise and relief, expept for frozen screws on deck fittings, they unscrewed as if they had been installed yesterday with little or no corrosion! relief. The chain plates themselves have surface rust and were actually loose in the hull compartments. I had to thread a similar size bolt in the holes beside the stainless rod anchor holes to make sure I could retrieve the plate for re install. I'm passing this along so that who ever wants to attempt this maint should have little fear and knowing how easy it can be, should be a regular occurance. If attempting for the first time though it helps to have a manual impact driver to get those stubborn screws loose. The original bedding, while adequate, no leaks, was pretty minimal so I rebedded with 4200 and installed with new screws. Anyway, I should have pictures and a story of the mast post repair in the next couple of weeks.
 
Sep 21, 2009
385
Hunter 34 Comox
I'm nearly finished! The post is in, mast restepped, shrouds tight and sail tested. I hope to spend some time soon posting the project in the mods section. This method ended up costing about 1200.00cdn including mast removal and install, machinists cost and stainless material cost. All that is left is to re fit the trim and connect the wires through at the mast base. Very happy with the outcome. cheers
 
Oct 14, 2007
64
Hunter 34 Milwaukee
looking forward to the pictures. Congrats, you should be set for a lifetime with that repair.
 
Sep 21, 2009
385
Hunter 34 Comox
Pictures of Fix from the top

I just spent about 3 hours writing out an excessively long story complete with pictures for the mods section, pressed submit and it disappeared. Does it take a while for this to get posted? Anyway, here are some pics of my nearly finished project. Just some cosmetic stuff left. Note my custom 5200 applicator.
 

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Apr 15, 2009
76
Hunter 27 beacon ny
Re: Pictures of Fix from the top

fantastic job. I planned the same fix for my 79 H27 last summer but made my flange the shape of raised base allowing me to weld pad eyes for vang and so on. I think this is the best all around fix for this stupid problem that could have been easily avoided during constructon at at no real extra cost. My leak from step allowed rain water to run down liner to portlight thought THEY where leaking. I may plan to fabricate these ssposts and make them available since I have sheet metal shop available....again nice job...cheers frank
 
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