Dennis wrote:Hello Frank
The drawing you attached is very interesting.
However, I am not convinced that Mary Ann's mast #100 has been constructed in that way.
The original SA masts are hollow, constructed using the "birds mouth" technique.
I can see why HM would devise a simpler method of construction, and also why they would plan to have the hollowing in the main body of the mast, in order to get nearer to the weight of the SA masts.
However, I managed to [color="Red"]push[/color] the aerial cable for my VHF through the mast. If the mast was hollowed as the drawing suggests I think it would have "bunched up" and jammed in the widened section. I suspect that my mast at least has a 15mm x 15mm square hole only throughout the length of the mast.
This suspicion is reinforced by the weight of the mast, mine weighs 27 Kg without any fittings.
If anyone can be bothered to find the density of Douglas Fir they could calculate what the weight should be for both a solid mast and one built according to the drawing.
erbster wrote:
Dennis was the string in place when you pushed your cable thru? What made you choose to do that rather than pull with string?
Dennis wrote:Hello Charles
I cannot remember why I pushed the cable through
I just know I did.
How I envy David Peck and his carbon fibre version.
PS When you do pull your cable through the mast, remember to pull another piece of string through at the same time, that way you will still have a cord to pull in future.
erbster wrote: However, I'm not sure about a carbon one- I like the look of the timber.
popeye wrote:Hi,
at the boat handover bob gave me the attached drawing of the mast. The drawing shows that the HM mast has a bigger cavity than the hole in the mast foot/bottom.
But I`m´not sure if the SA masts or earlier masts (older than boat no. 106) have the same dimensions.
You should talk to Bob about this.
Kind regards,
Frank
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