Comments on: Substituting aluminium spars on the Oz Goose sail boat

By: chrstjrn

chrstjrn — Thu, 22 Sep 2016 01:48:14 +0000

Thanks very much. The vendor says that the shipping has a surcharge for pieces over 58″. I’ve asked for more specifics about that surcharge, but I would guess I’ll end up with a 3-part. The vendor hasn’t responded with more specifics, yet.

By: admin

admin — Thu, 22 Sep 2016 01:37:01 +0000

In reply to chrstjrn.

Hi Chris,

Normally a two piece aluminium mast will be lighter than the timber equivalent. . A three piece mast starts to be somewhat heavier than a timber mast and four piece heavier still.

I don’t know why you are planning to double the wall thickness – it will be a tank. Is there a problem getting the approx 1/8″ wall in the table above?

if there is no real compelling reason to go four piece I would go two or three.

After all, the yard and boom are already longer than half the mast which defines the stowage length. Looks like overkill unless you have something really specific in mind.

Saving weight in the rig is probably four times more effective than saving weight in the hull, but both will give you noticeable differences.

MIK

By: chrstjrn

chrstjrn — Wed, 21 Sep 2016 17:49:39 +0000

Thanks very much, Mike. Re-examining this (after looking at the vendor and shipping options), I’m thinking of a 4-section. Bottom 2 sections would be 2.5 OD, upper 2 sections would be 2.25 OD, and top 15″ would be 2″ OD. All wall thicknesses would be 1/8″, not the 1/16″ mentioned above. Sleeves would be inserted 9″ into the outer tubes. Total weight for the mast would be around 25 lbs. Does that sound reasonable to you?

By: admin

admin — Wed, 21 Sep 2016 00:32:03 +0000

In reply to chrstjrn. Absolutely fine. One option is that the top third of the mast can be the same section as used for the sleeve. It will save a little bit if weight and the taper effect will help the appearance. MIK

By: chrstjrn

chrstjrn — Tue, 20 Sep 2016 23:34:21 +0000

I need to build a 3-part mast. Would 2 1/2 OD still be correct? I’m figuring my inner sleeves would be 2 feet each– 1 foot on each side of the split. Does that sound right? And is there any problem with using wooden yard and boom with an aluminum mast?

Thank you.