Mast Support Base Arrangement Question

[johnjfrake]

I am the new, proud owner of a Folksong 25 that I am restoring/improving hopefully making seaworthy.

The Z_spars mast is removed and laying close to the boat for work.

When I removed the support casting, aluminium sheet and teak plate I found a fairly messy sight with extra holes, damaged gelcoat etc. all of which has been repaired to a high standard. I now need to refit the aluminum mast support casting and am looking for some advice?

The original set-up had the teak directly in contact with the gelcoat with possibly a layer of mastic or paste between, I would perfer to use a thin layer of marine grade butyl rubber, are there any disadvantages to this or indeed is it worth while??

The aluminium plate rested on the teak wwith once again a layer of a white substance, now powdery, probably zinc chromate between. the two. Again would marine grade butyl rubber be an improvement and is it worth replacing the aluminium with 316 stainless steel plate??

Lastly should I use butyl between the mast support casting and the aluminium/stainless steel plate beneath it? originally there looks to have been the zinc chromate paste layer.

Thanks for you forbearance in reading above never mind any answers that come along.

regards



John

 

[oldsaltoz]

I am the new, proud owner of a Folksong 25 that I am restoring/improving hopefully making seaworthy.

The Z_spars mast is removed and laying close to the boat for work.

When I removed the support casting, aluminium sheet and teak plate I found a fairly messy sight with extra holes, damaged gelcoat etc. all of which has been repaired to a high standard. I now need to refit the aluminum mast support casting and am looking for some advice?

The original set-up had the teak directly in contact with the gelcoat with possibly a layer of mastic or paste between, I would prefer to use a thin layer of marine grade butyl rubber, are there any disadvantages to this or indeed is it worth while??

I doubt the rubber would spread the load properly over the area.

The aluminium plate rested on the teak with once again a layer of a white substance, now powdery, probably zinc chromate between. the two. Again would marine grade butyl rubber be an improvement and is it worth replacing the aluminium with 316 stainless steel plate??

Adding stainless steel in contact with alloy may cause more problems.

Lastly should I use butyl between the mast support casting and the aluminium/stainless steel plate beneath it? originally there looks to have been the zinc chromate paste layer.

This might be a good idea provided the rubber is at least the same size as the alloy plate, though you might get the edges bending up under load.

Thanks for you forbearance in reading above never mind any answers that come along.

regards

John

Good luck and fair winds.

 

[kds]

Mast support

Does the mast support casting fully bridge the space between the two bulkheads below deck ? If not, consider making one which does. This age of boat usually had the thrust of the mast just where you least want it - and after some years the support starts to give way.
I raised the foot on a 4 inch square Ali section which bridges both bulkheads.
A plate of ss or Ali is not enough.
A few designs had the mast directly above a bulkhead - much better ! I can't remember if the folksong did.
Lovely boat - a pleasure to sail !
Ken

 

[johnjfrake]

Thankyou both for your replys, I will also have a chat with my Rigger. The Folksong does have the center of the mast support plate over the bulkhead!

regards


john