35-2 Compression Post Keel-Step Block Replacement


Member II
I have a 1970 35-2 hull #154.

There is some deflection in the deck where it appears the mast may be sinking in, however I have no way to confirm or deny this as I did not notice until recently and don't have anything to compare against over the last year of ownership.

Some things I do know is since ownership I have tightened up all the rigging, and the bilge has flooded a few times soaking the wooden keel step block under the compression post.

I think I should replace this block with a slightly larger, non-compressable, non-rottable material.

Has anyone ever tried this before and can give me any clues about how the block is fastened in, removal difficulty, comments on the deck deflection, etc.?

I have read many of the other posts on this subject and have come to the conclusion the setup is NOT the same as on the 32's....

The 35's appear to have a steel plate embedded in the fiberglass which sits atop the compression post...

The compression post below deck is ever so slightly bowed to aft... but salvageable, I think, perhaps with the addition of a piece of stainless angle iron running it's length, securely attached on forward and port sides with.. lots of small screws? Fewer big screws? Don't know the best way to maintain the integrity of the post while adding strength.

There are no cracks in the headliner or the deck, and no signs of rust, so I will assume the steel plate is good...

I'm trying to fix this 'problem?' for rig safety and for peace of mind, hopefully without totally laying up the boat for months...

I do expect to have to pull the mast, which will be a first, however the mast could use a re-finish and re-wire anyway...

Thanks in advance..



Member III
I did a similar job on my 1975 E-32. The compression post went through the cabin sole and was stepped on a metal ibeam which had rusted and degraded, causing the compression post to move towards the keel. I decided to fix it once the cabin sole had developed a slight crack due to the compression post shifting.

What I ended up doing was de-tensioning the rig, and using a 4"x4" post on top of plywood to spread the load on the cabin sole, jacking up the cabin top with a bottle jack. This took the load off the compression post.

The hardest part was getting the old metal ibeam out. While it has degraded, there was still plenty of it there, and access was tight. I used a dremel with a cutting wheel and other tools to chip away at it. Once out, using a wet tile saw I cut a block of 4"x4" g-10, and fiberglassed it in place in the bilge, and then added additional 1/8" g-10 shims. I jacked the cabin top up a little to squeeze the last one in under the bottom end of the post, and slathered the mass in thickened epoxy.

Once cured, I eased the jack and removed the temporary post, then tuned the rig.

While the design of the E-35 may be different, I suspect the approach to fix your boat is pretty similar.

The repair was done 4-5 years ago, and the compression post hasn't shifted since. In terms of material, it was a cheap fix. The boat was out of commission for less than a week.


Member III
Blogs Author
I don't imagine the 35-2 is exactly like the 25+, but they both have a wooden block in the bilge supporting the compression post. Here's what I ended up doing:

It's held up really well for the past 5 years.


Member II
I like the stainless steel jack screw! Did you make that or buy it?

I'm not sure I would trust the force of the double spreader, 43' mast with at least 8,000lbs of downward force onto a small diameter threaded rod though, while bouncing around in rough seas...

Still very insightful! The 35 does not have the cross beam, bu the compression post is relatively well centered on the mast, just a little off towards the stern I believe.

I think I'll be reaching out to the yard to remove the mast, I do not like the idea of trying to do this with the rigging "loosened".

Will likely end up going with G10 blocks laminated with thickened resin, and create a solid fiberglass base that is level so the block can be square rather than oddly shaped.


Member III
Blogs Author
I designed it, purchased the material, and had a local fabrication shop build it. It was difficult to tell what the original material was since it was so rotten, but it looked like many pieces of plywood glued together and stood on edge then tabbed in place (not structually laminated). I'm confident the threaded rod will support the weight much better than the original configuration, especially over time. However, the loads on a 35 will be a lot greater than the little 25+.

The main problem I ran into was installing a block that was perfectly configured to the keel, the right height to support the mast, and able to install. If you have the ability to remove the cabin sole so you have access from above, it's a much more doable proposition. Otherwise you're left with having to hammer in wedges to bring the height of the block up to the bottom of the sole. On the 25+, removing the cabin sole would have required removing the main bulkhead which would require pulling the rig. In hindsight, pulling the rig probably would have been a good idea regardless of which way I went. I was able to reasonably mitigate the problem by loosening the rig and lifting the cabin top and mast with a bottle jack mounted on an A frame. I went really slowly alternating between loosening the rig and applying pressure to the pump. When everything was done, I came to the conclusion that one of the previous owners must have replaced the outside shrouds at one point, because they were short and needed toggles added.

If you can work around the access limitations, a block of G10 epoxied to the keel at the correct height will be stronger than the jack screw and last longer. I had the G10 idea floating in my head for a while. It will be really cool to see it in place. Good Luck!