Bundeenaboy said..

I am intending to replace my two headsail winches. Currently I have two Vantage winches which are past their usedby date. I am looking at the Harken Plain Top size B8 or the Lewmar Plain Top size 8A. The drum size on these is approximately 2&3/4 inches in diameter whereas the Vantages drum size appears to be 3&1/2 inches. I feel the new ones may not work as well as the old ones should. They are on a Southern Cross 23. Please gives me your ideas and why.

Compare the published "power ratios" for both winches. Winches get their mechanical advantage in two ways. The first is the internal gear ratio (G). The second is the ratio of the winch handle (L) over the drum radius (R). The product is called the power ratio, i.e., P = G x (L/R).

So the smaller drum size actually means MORE power, not less (all other things being equal).

For more info, I recently did a write-up on winches over on my blog at:

blog.arribasail.com/2014/03/tech-wonder-of-winches.html

You should be absolutely fine with a drum diameter of 2 3/4".

My Andersen 28ST and 40ST winches have drum diameters of 2 3/4" (70mm) and 3" (75mm) respectively. I use the former with my halyards for gennaker and mainsail, which are both 47 sq m in area. I use the latter for jib and gennaker sheets.

The design of the drum probably dictates how well the line will wind around more so than its diameter. For example, Andersen winches have these nice ribs which work a charm.

References:
http://andersenwinches.com/AW/product_details.asp?prodno=RA2028000000
andersenwinches.com/AW/product_details.asp?prodno=RA2040010000

PS As you can tell, I'm a fan of Andersen winches.

+++ For the Andersens, we had them on a 40 footer I sailed on and they never failed with some pretty hard work.

Bundeenaboy said..

Thanks to Scruzin, Sands and Fiesta. I considered your advice and bought the Andersen 10 flat top. I may be able to get an extra turn on the wince with this make. What do you suggest I use to fill the old winch screw holes with?

The easiest way would be epoxy resin mix (resin + hardener) with some "filler extender" mixed in.

www.whitworths.com.au/pnt-ht450-fill-92g?q=56060

Poodle said..

Seeing as a few people might be reading about your new winches, I have two decent winches for sail...

I'm in the market for a couple of winches - pics; info???

Poodle said..

Lazzarae said..

Poodle said..

Seeing as a few people might be reading about your new winches, I have two decent winches for sail...

I'm in the market for a couple of winches - pics; info???

Try this linky..... http://freodoctor.com.au/index.php?option=com_adsmanager&page=show_ad&adid=362&catid=1&Itemid=0

Thanks, I need bigger tho.