Alberg 30 Chainplates

[Cruiser2B]

I have a couple of questions regarding Alberg 30 chainplates, I am getting ready to remove the mast and replace the standing rigging. I was hoping to get new beefier chainplates made as well as replacing and upgrading the harware. Are all the chainplates for liner and non-liner boats the same. Mine is a liner boat#457, i know someone who has a non-liner boat that just replaced his chainplates that I may be able to use as templates. I am trying to cut down on the down time. if I had chainplates built and ready to go back in this would keep it from getting dragged out.
also do the chainplates actually need to be replaced? i do not see any corrosion, i keep reading that just the hardware should be upgraded. it still has original hardware, so i am guess the chainplates are too. I do someday " plan" on sailing across the atlantic in this boat so I want the chainplates to be up to the task.. If i do end up replacing them, what material? 316? silicon bronze?

[Captain Smollett]

I am not 100% sure, but I THINK the chainplates are the same for liner and non-liner boats.

The two big things I understand need to be beefed up are the bolts: either go from the original 1/4" to 5/16", or increase the number of 1/4" bolts.  This was actually the cause of Yve's dismasting...he did NOT upsize the bolts on his lowers and had one sheer off; the mast snapped at the lower spreaders.

The other thing is perhaps beefing up the knees to which the chainplates attach.  Or, eliminate the knees and go to hull mounted chainplates; if you do this, however, using the templates from a "stock" installation will probably not work.

I've not heard of anyone feeling the need to 'improve' the chainplates themselves..only the attachments.  Careful inspection for crevice corrosion and the like may reveal if they are re-usable.

Not sure if any of that adds to what you already know, but there are the specifics just in case someone else needs 'em.

[marujo_sortudo]

Aluminum or silicon bronze looks like the bronze to use, and personally I wouldn't use SS it can develop crevice corrosion, etc. that is not easily inspected.  YMMV.  Whether or not to continue with your existing chainplates is another matter better left to someone with more experience than me, but I would pull them and inspect them carefully to assess.  Here's some good, relevant threads if you decide to fabricate some:

http://www.briontoss.com/spartalk/showthread.php?t=1949
http://www.cruisersforum.com/forums/f116/converting-to-and-fabricating-bronze-chainplates-tangs-31447.html

I feel like I found this same poster discussing the completion of his project somewhere, but I'm not seeing that right now.  Maybe you can dig it up.

[Cruiser2B]

I took the plunge and decided to make my own replacement chainplates. i was going to use another Alberg 30 owners chainplates but that never panned out so i am just using mine. I pulled the lowers and they seemed pretty straight forward to duplicate. I ordered a 6ft 1 1/2"x.250 piece of 316L from onlinemetals.com. it was $70.02 delievered. here is a pic of my efforts today. I will use the old chainplates as backing plates. the old did not look too bad at all but i really have no way of telling. they are 41 yrs old.....time for replacements regardless. I made the 3 attachment holes 7/16 and the clevis pin holes 1/2. all of the new rigging will have/use 1/2 clevis pins in the sta-lok fittings.
This is as far as i made it today, i still have to do some polishing before i install them

[Bubba the Pirate]

Would love to see more pix and read about what you're doing/how it went.  Keep us posted.  I will be hip deep in chainplate replacement next summer.  My Cape Dory 28 is an Alberg as well. 

Todd

[Bill NH]

I will use the old chainplates as backing plates. the old did not look too bad at all but i really have no way of telling. they are 41 yrs old.....time for replacements regardless.

When I replaced the chainplate bolts on my old Alberg 30, I ended up doubling the knees they were attached to as well.  If I remember correctly, the forwardmost knee was even smaller than the rest.  At minimum be sure to try a few test borings in the existing knees and see if you find good wood under the fiberglass.  You may want to double up or replace/rebuild entirely.  As I'm sure you know, the chainplates will only be as strong as what they're attached to. 

I like your idea of using the old ones as backing plates!

[Cruiser2B]

I pulled the mast today, was not nearly as bad as I thought. Actually quite easy with the boat yard forklift/boatlift(dry storage type). found that my base plate on the mast is cracked/broken. I will take and post some pics as soon as I get a chance. Caught a cold and feeling a bit crappy. I already ordered all the lower sta-lok and and turnbuckles. I hope to get all the upper sta-locs and wire ordered next week when rigging only reopens next week. taking a quick look at mast and masthead is looks like i will replace all pulleys/blocks and wiring too. I dont want mast down too long!

[ntica]

Hope you don't mind me on your thread ??? But I've also done some new chainplates...

[ntica]

I need your epxpertis... I need to laminat the inside hull, where the chainplates will fasten. I was thinking of do some layers of "Rowing matts"(thingamajiggy ;D) will this be enough you think?

[Steve Bean]

Do you mean fiberglass "woven roving" ?

[s/v necessity]

I used woven roving in a simular situation on my boat, and was chastized by a good friend, who was knowledgable on the matter.  Here is what he said to me:  "Woven roving is acceptable when used with epoxy, but there are much better cloths out there, and why not use them?"  He reccomended a biaxial cloth with a matt backing to me.  (I dont think the matt backing was important, it's just that the cloth that was available happened to come with it)   

[ntica]

Yes I mean Fiberglass woven roving.
a friend sead place the fiberglass (WR) in a "peacock feather" pattern, towards the keel. and I will use epoxi.
what is: "biaxial cloth"???

[s/v necessity]

This looks to be the same as what was rec comended to me (although my stuff is a good deal wider than 6 inches)

http://www.jamestowndistributors.com/userportal/show_product.do?pid=1442&BINGSHOP

Bi axial means two separate layers of fibers each fiber oriented along a different axis.  Since the cloth is not woven it ends up being stronger (the fibers retain more strength since they run in a straight line)

This website has a decent explanation also.

http://boatcraft.com.au/Shop/index.php?main_page=index&cPath=40_42

Not only is the biaxial cloth stronger, You will also be able to get a better resin/fiber ratio with the biaxial cloth as opposed to the woven roving.