MacGregorSailors.com

There's a nice article on p 50, Cruising World, Sept 2013 on chainplate basics.

Some points: Inspect annually, ensure they are thick enough (many are not), 304 stainless is common - and prone to corrosion - 316L is better - keep it polished, etc.

Any suggestions on chainplate Johnson plate reploacement with a turnbuckle system?

The factory says that turnbuckles will turn due to the constant slack/tension of a mast that is raised and lowered, and are not recommended even when wired tight. Perhaps there's some locking version of a turnbuckle I've not seen.

That's a good observation - but my mast is raised and lowered twice each season.

mastreb wrote:The factory says that turnbuckles will turn due to the constant slack/tension of a mast that is raised and lowered, and are not recommended even when wired tight. Perhaps there's some locking version of a turnbuckle I've not seen.

mastreb wrote:The factory says that turnbuckles will turn due to the constant slack/tension of a mast that is raised and lowered, and are not recommended even when wired tight. Perhaps there's some locking version of a turnbuckle I've not seen.

All you need do is put a locking nut on the turnbuckle, Never had one loosen ever..

Can you name the turnbuckle you are using?

JohnCFI wrote:

mastreb wrote:The factory says that turnbuckles will turn due to the constant slack/tension of a mast that is raised and lowered, and are not recommended even when wired tight. Perhaps there's some locking version of a turnbuckle I've not seen.

All you need do is put a locking nut on the turnbuckle, Never had one loosen ever..

JohnCFI wrote:All you need do is put a locking nut on the turnbuckle, Never had one loosen ever..

Or a cotter pin on each end, assuming it's drilled for it.

But the problem with turnbuckles on these types of boats comes from bending them when the mast is not in place, and during raising. The vernier adjusters used on the Macs are supposedly much tougher than the skinny threaded ends of turnbuckles of similar capacity, which I believe.

I agree - my problem is getting to the plates when the boat is in it's slip.

tkanzler wrote:

JohnCFI wrote:All you need do is put a locking nut on the turnbuckle, Never had one loosen ever..

Or a cotter pin on each end, assuming it's drilled for it.

But the problem with turnbuckles on these types of boats comes from bending them when the mast is not in place, and during raising. The vernier adjusters used on the Macs are supposedly much tougher than the skinny threaded ends of turnbuckles of similar capacity, which I believe.

[quote="dlandersson"]Can you name the turnbuckle you are using?
[quote]

To be honest all I have are some cheepo jobs that I got a the hardware shop, they are just galvanised, cost a couple of pounds. when they start to lose the galvanising and rust I replace them.

Roger - what size do you use?

JohnCFI wrote:

dlandersson wrote:Can you name the turnbuckle you are using?

To be honest all I have are some cheepo jobs that I got a the hardware shop, they are just galvanised, cost a couple of pounds. when they start to lose the galvanising and rust I replace them.

Pretty sure they are about a 10mm thread, I will correct this tomorrow if I am wrong..