Kirt,

Finally got around to measuring some masts.

I made up cradles to support the mast in each plain out of 4x2 oregon cut to the mast profile. As a weight I used 2 X10 litre water containers filled with water and then weighed on accurate scales. I also used two water containers to wiegh down the saw horse end of the mast. When you tie the containers together they easily can hang over the mast to apply the 20kg weight.

I haven't managed to measure my 1997 mast yet I will post the info when I get to it.

I have measured 4 masts of the 2001-2002 vintage.

1,2 &3 have not been rigged and 4 has been sailed for 1 season.

I'll add it to your data,"0" is your mast in the table below.

MAST------0--------1---------2 -------3------4------ Range

Fore-aft: 48mm,-- 38mm, ---37 -----41---- 36---(35-45mm)

Sideways:179mm-165,-----165,----166---147-(140-170mm)

Lower mast bend-

Fore-aft: 12mm------9--------9-------9------8 -----(8-10mm)

Sideways: 47mm---38------39------41-----40---(38-48mm)



A mast will deflect under its own weight. especially in the side direction. What I measured was the increase in deflection when the 20kg weight was applied.

I tried measuring total deflection but that will measure differently depending on the tension of the string line used.

I decided measuring change in deflection by measuring the change in distanse between the scribe lines on the masts and the concrete path the saw horses were sitting on. I reasoned that this would give a more accurate comparison.





Regards,

Phill


I know that the voices in my head aint real,
but they have some pretty good ideas.
There is no such thing as a quick fix and I've never had free lunch!