Need to add a tang for hoisting

[roverhi]

Get a stainless steel tang and mount it above the spreaders with drilled and tapped fasteners. Use Blue LocTite, TefGel, or Lanocote on the threads. The tang can be used as a topping lift for the spinnaker pole that you'll be needing some day to pole out your jibs even if you don't ever get a spinnaker. If you are paranoid about corrosion, put electrical tape or some other insulator on the back of the tang where it touches the mast. The fasteners will be no issue if you do the above with the threads. If you want the tank to stay on the mast wouldn't use aluminum pop rivets.

If you want to add a spinnaker halyard, get a ss plate with eye(s) to hang the blocks off for the spinnaker halyard to bolt on the masthead. You can pick up a spare sheave at the masthead for an additional halyard if you run your jib and main halyards internal.
internal.

[UNCIVILIZED]

Probably your two best possible options are:
- Hang a block for the spin/second halyard off of a pin that's already built into the masthead box (assembly), as in this image http://www.blumhorst.com/catalina27/...ead_detail.jpg
- Or go to a masthead crane with a bail, & hang a block on the bail for the halyard, as pictured in several of the images here Rebuilt Catalina 27 Mast

Make sure that the halyard is led such that it won't chafe, both when in use, & when stowed on the mast.

Like Jim, & a few others, you couldn't convince me to go aloft on a tang alone, especially one fastened with pop rivets. And it just makes sense to go ahead & fully add another halyard, vs. a line attached via some weak, half-assed attachment system. As if you don't need the halyard, or aren't using it much, just lead a piece of 3-5mm cord up the spar in place of it. Then stowing the halyard proper, somewhere out of the reach of UV & chafe.

To which end, put a reeving splice in the tail end of the halyard, & ALL of your halyards. They take but 10min. to put in, & with them, swapping out a halyard is literally a 3 min. job. So that if you won't be using your boat for a few weeks, you can swap out all of your halyards with 5mm accessory cord ($0.10/ft), & save the wear & tear on them. Such is common practice on racing boats, & it adds YEARS to the life of your halyards.


PS: If you'll be flying a kite a lot, then a crane is the way to go, as they're much more chafe free. And routing the halyard intenally up to the crane is a smart move as well. Which, if such is proving problematic to figure out, LMK.

[Jim Cate]

Originally Posted by Madwand

Gotcha, I hadn't seen the edit. So if you look at this page
https://www.catalinadirect.com/index...sting-c-30.cfm
This is a newer model, but at the bottom are some pix of an older corroded one which I think is mine, although I don't really recognize it from my one trip to the top. But if you are referring to the pin between the two "ears," then I follow what you're saying.

Yes, basically that is the go. That pin is way stronger than any tang uyou could attach and will give a better lead.

Jim

[UNCIVILIZED]

Originally Posted by Jim Cate

Yes, basically that is the go. That pin is way stronger than any tang uyou could attach and will give a better lead.

Jim

Jim, while your suggest method may be a bit stronger (depends on how a crane's built & attached). Usually a bail (or two) incorporated into a proper crane will give you a much better lead. As it puts the halyard quite a bit further out in front of the stay, so that there's much less possibility of chafing. At least so long as the run from the block on the crane to the mast is fair, you have a net gain.

Plus of course with a well designed crane you can incorporate Port & Starboard bails, so that 2 halyards can be run if such ever strikes your fancy. Not an uncommon thing on racing/performance oriented boats. And this option is even more chafe free, assumng that you don't cross the halyards over centerline when flying things from them.

[Redpcx]

DO NOT use aluminum rivets. Hollow STAINLESS STEEL rivets are VERY strong, and the tang shown is sized for stainless tell pop rivets. Materials are compatible. Oh? you have some question whether you can mix stainless and aluminum? Go to your mast, not mine, and see if they have been mingled. Oh? They have? Well the question is settle for all practical purposes.

Now Three problems you will have with using pop rivets.
1. Finding the right ones, they have to be a snug fit in the hole in the tang.
If one size is a little loose, go up a size and redrill to a larger size..
2. You must use the perfect drill size to achieve proper strength. It will NOT be a fractional inch size. A letter size, or number size for little ones.
3. The riveter required is a bit big. If it is hand powered. Borrow one if you can, it will probably be an inline, takes two hands to use it even on tiny rivets.

As you drill the holes, put a rivet in to hold the alignment, and tape it to hold it. DO NOT set any rivets until all holes are drilled, and burrs in between the parts are removed. Be real careful before setting the rivets, slide all in the holes. They are much harder to drill out than the aluminum mast.

If you do a bad job, it is a crap job. I recently installed one on a friends mast. we did an informal test with just one rivet. no deformation with about 200% load. So with all 3 rivets in, at least 6:1 safety.

Big hard rivets, big riveter. I had the riveter (from real work) and had to buy rivets.

[hamburking]

Originally Posted by Jim Cate

In the distant past, when I had a Yankee 30 and a ~10 year old son, he used to love to swing from a spare jib halyard which ran through the normal sheave in the masthead. A few sundays worth of that game chafed the halyard to an unusable state. Grrr...

Yes Jim, having kids aboard is just awful. Like the OP, I didn't have a spare halyard, so I would hang mine from the end of the boom until they were nice and dry, then stow them in a cockpit locker.

[Jim Cate]

Originally Posted by UNCIVILIZED

Jim, while your suggest method may be a bit stronger (depends on how a crane's built & attached). Usually a bail (or two) incorporated into a proper crane will give you a much better lead. As it puts the halyard quite a bit further out in front of the stay, so that there's much less possibility of chafing. At least so long as the run from the block on the crane to the mast is fair, you have a net gain.

Plus of course with a well designed crane you can incorporate Port & Starboard bails, so that 2 halyards can be run if such ever strikes your fancy. Not an uncommon thing on racing/performance oriented boats. And this option is even more chafe free, assumng that you don't cross the halyards over centerline when flying things from them.

Unciv, you are escalating the OPs situation a bit here!

From his initial post:

I wanna add one of these to the upper end of my mast for hoisting the water toys on and off the Catalina 30 foredeck, <100 pounds at a time. Maybe hang a swing from it.

While I agree that double cranes are great for actual spinny halyards, the installation of such for the above usage seems way overkill and over expense when he (I suspect) already has the hardware to hang a single block from the masthead fitting.

Jim

[Madwand]

Yeah, really just an extra hand for launching and retrieving the dinghy and sea kayak. 79 and 70 pounds, respectively. I can easily lift their weight, but at 8.5 and 11.5 feet, they are two awkward to pick up.

[Deltasailor]

As pointed out in other posts use the masthead cap to fix a block to.
A tang a few feet from the masthead would be subject to one hell of a jolt should you fall in the event of your halyard breaking. I doubt it would survive, nor would you!
The old way of preventing stainless screws corroding the ali is to use lanolin.

[Peter1949]

Is there a Catalina owners web site that could answer your question?

[Madwand]

I asked.

[chris95040]

Originally Posted by Redpcx

Materials are compatible. Oh? you have some question whether you can mix stainless and aluminum? Go to your mast, not mine, and see if they have been mingled. Oh? They have? Well the question is settle for all practical purposes.

Folks have already addressed the aluminum/stainless issue. They even mentioned the importance of isolation (tef gel, blue loctite, tape, etc) which you, surprisingly, did not.

And I can't imagine why someone would choose to use pop rivets on their own boat, unless they absolutely had to... Man the fun I've had removing riveted items once I found the right mix of momentum and approach. Though thats a little unfair, those were aluminum.

[Madwand]

You might imagine they'd do it if they want to attach aluminum to aluminum without having corrosion. If I want to lift 100 pounds and an aluminum rivet has 300 pounds strength, how hard is it to understand that 3 rivets in a tang will give 900 pounds of strength where only 100 is required, without corrosion? Or that the person asking has no other reason to think it's unacceptable? Simple.

[Dave22q]

The easy way is mount a stainless ring or heavy eyebolt well below the forestay with a matching cleat below to stow the line. Drill, and tap works well. You do not want to hang a block and drop a line from a masthead bale unless you want to make tacking more interesting.

[Madwand]

Originally Posted by Dave22q

You do not want to hang a block and drop a line from a masthead bale unless you want to make tacking more interesting.

Well, that is interesting, since I recently had to replace my roller furler and add a restrainer due to a bad halyard angle and a halyard wrap. I certainly don't need more interference up there now. I'm back to wanting a tang and a becket pulley like I originally asked for. So I need to get the tang I pictured, some tefgel, and a tap for some SS screws. And a cordless drill...