Dorade vents MarkII

[willie]

Does any one know the thinking behind Catalina removing the dorade vents from the newer production boats? And is it a problem with out them... getting enough ventilation.

Thanks

[Stu Jackson]

Willie

Thinking?  It's more like "what were they thinking?"

The Mark II brochure claims a lower profile and "sleek" lines.  See: http://www.c34.org/brochures.html, from the Original C34 Homepage.

With solid triple hatch boards on the Mark II, compared to the two on the Mark I, one of which has slits, it seems that passive ventilation is measurably reduced on the Mark IIs.

Of course, Mark II owners do NOT have the problem of replacing the dorade vents (see Mainsheet Tech Notes for a replacement project I documented http://www.c34.org/mainsheet/pdf/Aug_2005.pdf), or of trying to keep them clean, to say nothing about having the mainsheet get caught up on them... 

It's a boat, there are compromises.

[If you are not yet a C34IA member and the link above doesn't work for you without a password, you can join the Association and obtain access to all of the C34 Tech Notes from 1987 via "Tech Notes Online", which are PDF versions of ALL the C34 Tech Notes, pretty much up to date.  The Tech Notes Index, {2005 is: http://www.c34.org/tech-notes-index/tech-notes-index-2005.htm, and the whole Index is: http://www.c34.org/techindex_top.htm) is available to everyone, so you can see the topics that have been covered over the past 20 years.]

Mark II owners can chime in on what works for them for ventilation.

[Roc]

I always keep the small hatches in the head and aft cabin cracked open when I'm away.  They are under the dodger, so no rain seems to get in.  I keep them open about an inch..

[Ron Hill]

Willie : If you really want the answer to your question, call Jerry Douglas at Catalina. 
He the designer and can answer it, not the speculation from a bunch of C34 owners.   

[Jeff_McKinney]

Stu,

With all due respect to your expertise and knowledge I must disagree with one statement in your reply:

          "With solid triple hatch boards on the Mark II, compared to the two on the Mark I, one of which has slits, it seems that passive ventilation is measurably reduced on the Mark IIs."

Apparently the issue of diminished air flow in the cabin has reached someone out west. While there are indeed 3 solid hatch boards on my boat, there IS a ~1/2" wide X 8" long slot milled into the joint between the two upper boards that lets air through. It's not the world's best air flow, but it's decent. With the dodger up I have yet to see rain blow in unless I'm tied up at the dock AND the wind goes over 20 knots from dead astern. No need to leave the two small hatches open.

[reedbr]

I've got the hatch vent groove between boards 2 and 3 on my MkII.  I also leave my two small hatches under the dodger in the vent/lock position while away.  I.E. the hatch is open ~1" but you can still lock it in the second groove of the aluminum trim ring.  I leave both the head and aft cabin doors ppropped open.  However, the boat still doesn't vent enough and has that cooped up smell for the first 5 minutes I'm onboard.  I suggest mushroom vents on the main salon hatch and possibly on the forward harch, maybe even solar powered vents.  I just haven't had the guts to cut into my hatch plexi yet.