Aluminum mast size

[willy13]

I'll say it, lol, .134 wall will be fine.

 

[abosely]

Lol Thanks Willy13!

For corrosion protection will be using Rustbullet coating on inside and outside of masts.

The stuff bonds extremely well to aluminum, won’t flake or peel and is very abrasion resistant.

For marine use a 12-15 mill dry film thickness is recommended applied in multiple thinner coats. All corners & edges will be eased so coatings have radius not sharp corners.

Will come up with a swab to run through masts to apply it to interior.
Will put 2 coats of WhiteShell gloss protective coating topcoat, gives a smooth surface inside masts.

50’ endoscopes are pretty inexpensive now and the white interior will make it easier to see condition of interior when putting camera through masts for inspection.

Exterior of masts will be coated with 12-15 mill DFT and top coated with epoxy paint.

All surfaces of masts & brackets will be coated with no bare aluminum anywhere.

Cheers, Allen

 

[Stijn]

Hi there.

Sadly I dismasted at sea with a Tiki 38 on my maiden trip. After talking to Hanneke Boon, I realised the mast steps were build for a Tiki 21 or 26 as the builder had build a Tiki 21 or 26 before.

As such, I am in the process of thinking about new masts (I do not trust the remaining mizzen anymore as you might understand).
I will build proper Tiki 38 mast steps and would prefer aluminium masts to the hollow wooden ones that were there.

Has any of you had any luck in buying the right aluminium poles or masts and could you kindly point me on the right direction?

Many thanks!
Stijn

 

[gonzo]

So question is will Schedule 10 pipe in 6061 T6 with 6.625"/168.3 OD, .134"/3.4 mm wall be adequately strong instead of 6"/152 mm, 4- 5 mm wall of unspecified alloy?

In short, no. The wall thickness is specified to take into consideration point loads that would crush a thinner wall. Also, a thin wall will buckle at a lower compression load when a point load is applied.

 

[TANSL]

Also, a thin wall will buckle at a lower compression load when a point load is applied.

No, that is not entirely correct. The buckling resistance, for the same material and for the same length of the column, depends not only on the thickness of the section but also on its polar moment of inertia.

 

[gonzo]

The polar moment of inertia of a thin walled shaft depends on the difference between the inside and outside diameters. It is the capacity to resist torsion, which is not quite relevant for this discussion.

 

[TANSL]

OK, @gonzo, whatever you say. It's not worth continuing.

 

[Stijn]

Hi there!

I have contacted two companies, Aalco in the UK and a company here in Greece.

They both can supply me with 11m, 140mm outer diameter, 5mm wall thickness, alloy 6082, tempered T6 tubes.

Price seems reasonable but I need to take 8. I would like to have two. Anyone interested?

Stijn