Cd 28 halyards

[Benlieb]

Easy question:
I have a cd 28 late 70's model wondering what
the halyard diameter is supposed to be.
Mine were too big for the shiv I think.
Also looks like there is a groove for wire.
What is that size?
Also would like to talk to anyone
Who has installed a compression post on
This boat.

Thanks from a new poster

[Anthony P. Jeske]

Hi Ben;
The owners manual lists 7/16" x 72' for the main halyard.

The groove in the sheave is for the old wire to rope halyards that were once popular. The wire didn't stretch as much as the fiber line, but the wire/rope lines were expensive, and developed "meathooks" that were hard on your hands. New low stretch line material has eliminated the need for this type of halyard.

There's a large steel plate set in the cabin top under your mast step. It transfers the load to the bulkheads between the salon and the head and to the bulkhead between the head and the forepeak. Unless you have serious issues with this plate, you don't need a compression post. Did a previous owner do some modifications to the bulkheads? Is there visible depression in the cabin top?

Good Luck,

Tony Jeske
C&C 27 MkV
FLYING CIRCUS
Silver Gate YC
San Diego

[Benlieb]

Tony,

Thanks for the info.
The thing about the compression post is I don't trust the steel structure under the step.... I know it has leaked there for years. Just installed new external chain plates because the steel backing plates on the old setup were rotted away, and the deck was beginning to rip up. I understand that it's a roughly 2x4 piece of rectangular tube in there, not sure of the thickness. I need more info whoever is out there.

Thanks, ben

[Maine_Buzzard]

You can easily downsize to 3/8" or even a 5/16" T900 type hybrid wonderbraid for the halyards.

Your feel of the rope is as much of a concern, with smaller diameters hurting my hands. Hell, 5/32" Dyneema probably has less stretch than the original 7/16" double braid that was supplied. I'd hate to tail it though.

The wire halyard half was likely 5/32. Does anyone even splice wire to rope any more??

[Steve Laume]

I used 7/16 XLS and wish I had gone down to 3/8. The XLS is very strong with very little stretch so you don't need to use the old diameter as a guide. The stuff is also stiff, so a smaller line would have some advantage. It would also reduce windage by a small fraction.

The mast base structure on Raven is more than just a singular metal tube. It is quite robust and spreads the load out very nicely, Steve.

[Benlieb]

Solid advise thanks all.

Still curious anyone done a compression post on a cd 28?

[Steve Laume]

The CD-28 and 30 are very similar. On Raven a compression post would wind up square in the middle of the opening for the door to the head. Not sure this would be the best arrangement so I doubt anyone has done it. Lot s of Typhoons with compression posts but I have never heard of any of the larger Cape Dorys needing or adding a post that was not in the original design.

If you think you might have a serious problem with the steel structure that supports the mast, you might grind away the glass to either repair it or ease your mind before trying to install a compression post. The original design is very good and I have never heard of a failure in that area either. If it has been leaking for a very long time it could be an issue but you would want to get rid of the rusted metal before you installed a compression post anyway. If you are going to address any rusted metal you might just as well fix that and forget about the post.

Just my opinion but it is a good design that spreads the load over two bulkheads. This allows an unobstructed cabin area and eliminates the problems of trying to take the forces down to the keel.

Do you have noticeable problems with the mast support structure? Blistering, delamination, movement, sagging?

If it isn't broken why would you try to fix it, Steve.

[chelininger]

Compression post replacement, stay conversion from deck to hull with titanium, new rigging & other for refit of 28' currently underway - will post photos/process coming up. What an experience...whatever you do, don't drill a hole in the metal post & not seal it properly...

Anyone have spec & good photos of rigging for 1978 '28?

[tjr818]

Tony,

Thanks for the info.
The thing about the compression post is I don't trust the steel structure under the step.... I know it has leaked there for years... I understand that it's a roughly 2x4 piece of rectangular tube in there, not sure of the thickness. I need more info whoever is out there. Thanks, ben

Does anyone have information on the steel deck reinforcing? A steel plate would not do much, but a 2x4 tube would be very strong. Has anyone exposed the steel to see wha tit really is?

[hilbert]

Fred installed a compression post when he prepared his 28 for circumnavigation.

He wrote "The compression post. This is made with a piece of 1 & 1/2" schd 40, 304 grade SS pipe. At the top is a Dwyer mast base plate welded to the post. I have leveled the top of the ballast where the post will rest inside the boat. On top of the leveled area will sit a 6" square X 3/8" thick SS plate. This will have a SS slug welded to it's top surface that keys into the bottom of the post. The old mast step casting will be reused. It was bolted to tapped holes in the steel molded into the deck. The steel in the deck is a 2" X 4" rectangular box section. It is hollow inside. When reassembled the mast step will be bolted all the way through the deck. I will cut the pipe a little long so that the deck is lifted to the bottom of the Dwyer plate. This way the principle load bearing is handled by the compression post and not the deck and bulkhead structure. Many Cape Dory owners have noted gelcoat cracks near the forward cabin top hatch and mast step. This is not caused, as the popular theory presumes, by excessive thickness in the gelcoat. It is caused by the cabin top mounted mast and it's associated compression loads. The compression post will be about 6' 4" long when finished."

More information is available by going to http://www.sbastro.com/FeNIX/Projects/P ... temsFS.htm and clicking on "Rig". You can also find his posts on this site by searching "fenixrises".

[hilbert]

Does anyone have information on the steel deck reinforcing? A steel plate would not do much, but a 2x4 tube would be very strong. Has anyone exposed the steel to see wha tit really is?

After Roberto posted a reference to Paul Calder's blog about the restoration of a Cape Dory 27, I took a look and found that he had posted pictures of the rectangular 5" x 2" mild steel under the mast step. Very cool to finally see what was used and how it was positioned. http://www.sailfeed.com/2015/09/mast-st ... ollective/

[tjr818]

Thanks hilbert.
As an owner of a 27 I find this very reassuring. Ours has always been freshwater boat and the mild steel has held up well. Here is a photo of the chain plate "metal reinforcement" called out in the diagram from the owners manual. It still has the original steel fabricators red oxide primer that is in decent shape. In fact the primer is so good I wonder if the bonding wire is really making any contact. The mud daubers don't seem to mind the primer at all.

Chain Plate & Mud Daubber.jpg

[Jim Walsh]

Does anyone have information on the steel deck reinforcing? A steel plate would not do much, but a 2x4 tube would be very strong. Has anyone exposed the steel to see wha tit really is?

After Roberto posted a reference to Paul Calder's blog about the restoration of a Cape Dory 27, I took a look and found that he had posted pictures of the rectangular 5" x 2" mild steel under the mast step. Very cool to finally see what was used and how it was positioned. http://www.sailfeed.com/2015/09/mast-st ... ollective/

Pretty interesting. Thank you for posting. The article initially seemed negative and I nearly stopped reading since I'm one of those who recognize that Cape Dory overbuilt their boats as opposed to some of the real crap which was available, in the 70's in particular. Then the tone of the article changed once the grinding wheel had done its work to expose the suspect box girder. It was in perfectly serviceable condition after nearly four decades. Good job Cape Dory!

[Jim Walsh]

Thanks hilbert.
As an owner of a 27 I find this very reassuring. Ours has always been freshwater boat and the mild steel has held up well. Here is a photo of the chain plate "metal reinforcement" called out in the diagram from the owners manual. It still has the original steel fabricators red oxide primer that is in decent shape. In fact the primer is so good I wonder if the bonding wire is really making any contact. The mud daubers don't seem to mind the primer at all.

Chain Plate & Mud Daubber.jpg

That chainplate reinforcement looks like it was installed yesterday. Fantastic.
Cape Dory was evolving and clearly striving to improve their product as they matured as a Company. My CD31 is an 84 model (hull number 27) and one of the construction improvements which was implemented was changing the chainplate reinforcement from mild steel to 1/4" aluminum which, in my particular case, extends under all four chainplates (the CD31 is a cutter, hence the extra chainplates). I don't know if they implemented this improvement across the entire product line from this time forward but it should have been. Cape Dory's really are very well built for production yachts from the era in which they were produced.

[chelininger]

Here some photos of mast step removal taken from CD 28 #214 part 1