Another centre board removal question.

[TheMonk]

After inspecting my I563's centre board from underwater I have decided to pull it out for either replacement or refurb'. I have read over the information on the site and have begun by chiseling away and extracting the pivot bolt. So next step is to jack-up the boat in situ on the trailer, block it up and pull the CB out.

So I have a couple of questions from those that may know. Firstly, in the topic Swinging Swing Keel, an entry indicates they have done the same job and had replaced the spacers with a material that might be laminex, am I right? Then in the same series of photos the pivot bolt has a neoprene bush and 2 washers, can anyone advise me what material these 2 washer are made from?

Also, on pulling out the CB is it worthwhile trying to salvage this badly rusted CB? My mate reckons that steel will rust again after treatment as the salt has impregnated the surface!

I feel I would like to refurbish the old CB but I guess the over all condition will dictate this.
What cost are involved in re-galvanizing an old CB and what am I up for to replace it with
an aluminum replacement? Finally, is anyone using anything other than SS wire cable,
maybe that super strong rope, the name of which escapes me now.

Thanks John.

[Yara50]

John
Yara has an aluminium c/b and it is extremely light. With aluminium you coulf use either stainless or spectra due to its low weight. Even my 10 yo can lift it literally single handed.

[TheMonk]

Thanks Yara, I've seen your posts and have learned from you. Did you do the CB or do you know where it was fabricated. I guess when I pull it out I'll just take it down to one of these aluminium blokes and get it coppied.

Does your spectra line extend to and attach directly onto the CB or does it attach onto a cable?
Thanks John.

[graham5494]

Gidday all . I would recommend using stainless wire , not from a strength point of view , but because of abrasion resistance . The wire runs up a fairly narrow tube into the cabin , so swages need to be tight . One swage can be made on the bench but the lower one has to be done under the boat . Make sure that the wire is routed correctly . On mine I simply ground down the rust scale with an angle grinder , then applied two coats of epoxy paint. I was lucky to find a boat position on the trailer where the board slipped out between rollers . Watch out for the board falling and taking out , a chunk of body part !

graham5494

[graham5494]

Gidday all . Thinking on a bit.... be careful using aluminium in salt water if there is any chance of contact with stainless steel , remarkable corrosion can result ! Has anyone tried laminating a board using epoxy and glassfibre ? Perhaps alternating layers of chopped strand and unidirectional would work best !

graham5494

[Yara50]

Yara's aluminium centre board has been installed for many years and shows no sign of corrosion.
When I get a chance I will try to make the drawing of the centreboard in the technical section more readable.

I have now attached a downloadable PDF file in the technical section, of the drawing for the centreboard. I have not checked it, but believe it is suitable to make up a new one from scratch, in whatever material takes your fancy. Unfortunately it does not nominate material thickness, but you can guesstimate from your existing. It would also be improved if radiused corners in plan view/cross section were added.

I personally am very happy with my aluminium one.

[TheMonk]

Hi all, pulled out the CB and it was beyond repair. Have taken the old one down to an aluminium bloke at Brookvale, he has quoted me $140 for a duplicate cut in 10mm aluminium. A bargain I reckon!

Can anyone advise me about the spacers, can I use laminex? Also the pivot bolt, should I use sikaflex or anything similar?

Edit. . . . Someone on the Trailersailerplace website advised me to ensure the aluminium CB in insulated from the SS pivot bolt to avoid the aluminium from being eaten away. Can anyone advise me on a solution, a grommet or maybe a suspension bush. I did read a post on the very same issue but now I can't find it.

John

[Yara50]

John
Take a look in our Technical section. I have copied an old thread regarding centre board replacement, which has more info. Yes, you need a bush around the centreboard pivot. See http://www.investigator563.com/forum/vi ... ?f=4&t=167
In fact this thread should be in the technical area.

[TheMonk]

Well the job's completed, picked up the aluminium CB this arvo and a few hours later she's in. I placed a neoprene suspension bush in the pivot hole and laminex as spacers, as per the above link from Ian.

Looking from underneath, the CB cavity had a few small cracks located at the fore and aft end of the casement, the point nearing the hull. I re-glassed these cracks and also epoxied in a couple of imperfections near the pivot holes. The boat had a little leak but I couldn't identify the source, this might be the culprit.

The job of aligning the pivot holes and inserting the pivot pin was something I thought I was going to struggle with, especially attempting it solo. Then lo and behold. she goes in on the second attempt! As a rule, Murphy's Law is strictly enforced on me when attempting these little jobs. Today he left me alone.

The CB lifting line appears to be Spectra and extends down to the CB itself. I'll just re-tie it and use that.

So thanks for the tips, I hope to be in Pittwater this weekend.

John


























to a new hole at the rear of the CB.


















I will re-glass the pivot bolts tomorrow