Bimini and boom clearance

[stuendan]

Put up bimini on "Genesis" (26M) first time while sailing on weekend and found I had to pull the boom up (via topping lift) about 6 inchs to get it to clear the bimini when centred (more while erecting bimini). Is this right? I think the sail shape would be less than optimal, with topping lift rather than sail determining boom height Could there be a problem with my rigging? Forestay too long perhaps, although shrouds appear tight enough. Any thoughts?

[sunshinecoasting]

Hi, you didn't mention if you have a vang or not, my had the same problem but I soon learned that you need to do two things, one, release the vang a little so that it still controls some lift but let's the boom up a little and two, adjust your bimini so the front cross bar leans forward a little making it lower and move the middle cross bar up or down on the rear strut until it flattens the top of the bimini out, this also makes your bimini just a tiny bit longer giving you a tad more shaded area, both of these adjustments allows me to keep my bimini up all the time when under sail without fowling the boom. Up here in the tropics you cant sail without the bimini or you will fry. I must say thought that not being able to readily see your sail from the drivers seat makes trimming awkward.

Cheers, Dennis.

[bartmac]

I wouldn't play with the vang and topping lift to accommodate the bimini....rather I'd adjust/modify the bimini....to compromise sailshape on an already slow sailboat is just not going to make for very good sailing....you would be wise to check your mast rake....ours was way out and made for real sh~t sailing....every gust rounded us up badly.Maximum front stay adjustment....maybe I should call it minimum ie shortest didn't allow for the problem to be solved....so rather than frig with the stay length I moved the top mounting up about 50-75mm which then meant I still had some adjustment up front...obviously side stays had to be attended to

[DaveB]

Look at your mast rake aft. To far aft more than 1.5 degrees will cause boom to hit bimini.
Personally I like a 1 degree aft mast rake on my heavy loaded MacX. Just right for weather helm beating to windward. Also gives more clearance for boom to bimini clearance.
If that doesn't change it than raise the Goose neck or recut the main .
Dave

Put up bimini on "Genesis" (26M) first time while sailing on weekend and found I had to pull the boom up (via topping lift) about 6 inchs to get it to clear the bimini when centred (more while erecting bimini). Is this right? I think the sail shape would be less than optimal, with topping lift rather than sail determining boom height Could there be a problem with my rigging? Forestay too long perhaps, although shrouds appear tight enough. Any thoughts?

[DaveC426913]

My boom falls well under my Bimini. If I douse the sail, I have to push the boom outboard past the bimini edge before I can haul it up out of the way with the topping lift.

It sounds to me like y'all's booms are above the Bimini?

[Wind Chime]

Our boom clears our dodger and bimini with the boom mounted in the factory height position with a standard size main sail.

We have the standard BWY wide dodger, with a custom bimini and full enclosure that matches the dodger height.
We can sail with this configuration by removing the connector piece between the bimini and dodger, and removing the front side panels.

There is not a lot of clearance but the boom never rubs on dodger or bimini, the boomkicker helps with this as well.

[stuendan]

Thanks for the input guys. I noticed that the manual gives a sketch (page 11) with dimensions to check the mast rake. I'll definitely start there. Appears that some of us out there have full clearance with standard setup and others not. I'm fairly sure that the boom should clear bimini and dodger or else the designers need a good talking to! Cheers all

[Wind Chime]

Hey stuendan,

To my knowledge, Mac’s were never designed with a dodger or bimini (except the pop-top on classics). Meaning they did not come from the factory with this as an option to the dealer. Dealers added dodgers, bimini’s, and full-enclosures as after-market options or we install them ourselves as modifications.

So it’s a bit of the chicken and the egg - the dodger and bimini need to fit under the standard height of the boom the way the boat was designed, not the boom being high enough to clear the dodger and bimini. Hope that made sense

by stuendan » Tue Dec 10, 2013 2:48 pm

Thanks for the input guys. I noticed that the manual gives a sketch (page 11) with dimensions to check the mast rake. I'll definitely start there. Appears that some of us out there have full clearance with standard setup and others not. I'm fairly sure that the boom should clear bimini and dodger or else the designers need a good talking to! Cheers all

[bartmac]

Given the number Mac produced and the mods inflicted on some.....assuming the boom clears the bimini could land you in trouble.The whole mast rake adjustment should not be about boom/bimini clearance but about weather helm....careful because the over adjustment could lead to lee helm and on a Mac that would not be desirable.There's been discussions about raising the boom gooseneck (should mast length allow) which would certainly make for boom/bimini clearance but at what cost in terms of a already tender boat become more tender???
I've seen a trailersailer which have experimented with lowering the boom and also using sailboard style booms to lower the sail and extract more go out of their rigs???

[DaveB]

On my 1997 MacX I had to cut the bimini support poles down to sitting down at Helm gave me 5 inches of headroom below bimini. My mast is raked aft 1 to 1.5 degrees and is great for weather helm and boom clears bimini 1 inch close hauled.
Order a new Main Sail and cut 4 inches short on leech, or raise gooseneck or if your mast is raked more than 1.5 aft than straighten it.
I was probably first one who ordered a new main from Judy ( stock MacX size) and advised her to shorten the leech and think she did.
I do have another larger bimini I use during the summer here, mast off and full standing headroom under bimini. (here in FL. hot days and calm winds I like doing day launches)
Dave

Given the number Mac produced and the mods inflicted on some.....assuming the boom clears the bimini could land you in trouble.The whole mast rake adjustment should not be about boom/bimini clearance but about weather helm....careful because the over adjustment could lead to lee helm and on a Mac that would not be desirable.There's been discussions about raising the boom gooseneck (should mast length allow) which would certainly make for boom/bimini clearance but at what cost in terms of a already tender boat become more tender???
I've seen a trailersailer which have experimented with lowering the boom and also using sailboard style booms to lower the sail and extract more go out of their rigs???

[DaveB]

Nice Pictures, whats the year of your MacX ? I think Rodger raised the gooseneck and maybe the Leech after 1999.
Think Dimitri can chum in on this as his 2000 MacX has a lot more bimini clearance than mine.
Dave


[quote="Wind Chime"]Our boom clears our dodger and bimini with the boom mounted in the factory height position with a standard size main sail.

[Wind Chime]

Thanks Dave,

Ours is a 2000X.
We bought the 2000 specifically because it had some changes released that year. Most notably for us was the change from a plastic companion way step (with ballast vent hole inside) to a solid stainless steel and wood three-stair ladder, as well as more efficient rudder design and stainless steel brackets. I can not comment on whether the gooseneck is higher or not.

by DaveB » Wed Dec 11, 2013 4:47 pm

Nice Pictures, whats the year of your MacX ? I think Rodger raised the gooseneck and maybe the Leech after 1999.
Think Dimitri can chum in on this as his 2000 MacX has a lot more bimini clearance than mine.
Dave

Our boom clears our dodger and bimini with the boom mounted in the factory height position with a standard size main sail.

[Nick]

A slightly different way of setting up a bimini. More than 6'2" of headroom at the wheel As long as you keep the boom vang cleated there is no interference with the sail or boom. Essential when the admiral is a redhead and burns easily. Obviously you can't link it with an infill to a dodger( if you had one.)



Cheers Nick

[Boblee]

Got to agree with Bartmac all the way here, modify/move your bimini to clear the boom not the other way round.

[TessabelleNJ]

Hi all I'm hoping someone can help me out and I hope this doesn't come off as bashing to BWY, but from looking at the specs of their Bimini for the McGregor 26x it seems that they are made of aluminum frames only and yet they're asking $600 for basically the same Bimini I can find online anywhere else for under $300.
Is there any justification for this increased price?
Can anyone compare the BWY Bimini to an off-the-shelf Bimini of the same dimensions?
Thanks for any information you folks can provide.
Larry