lowers

[matt (Guest)]

Hi,
I've got the standard lowers setup in N3486 but have usually set it up for reasonable mast bend in the lower section of the mast and not ever adjusted it during racing. I'm using a superspars carbon mast btw. Now I know that the accepted wisdom is that if you don't let the lowers off down wind in a blow you risk breaking the mast but I have never experienced that problem.
So now I'm thinking that I can save some weight by removing all the purchase blocks and simply tieing the lowers at the required tension pre-race a-la cherub rigs. Simplifying the cordage at the mast foot in the process.
Is this a fair analysis of the 'effective' use of lowers - or have I missed something important that does require dynamic lower control?
Matt

[andyp]

Hi Matt,
Do we take it from the lack of replies that nobody else knows what to do with them either?

[Antony (Guest)]

Matt/Andy,
I think that this one got missed out.  A lot of us do adjust them.  My basic rule of thumb is Reaches - On, Run and Beat - off.  We use a mast ram for adjusting the bend upwind as we have both, if you only have lowers as some boats do then use them to control bend upwind. 
The main purpose of lowers has always been to stiffen the mast, and so power up the mainsail, on a reach.  If you cannot adjust them and set them up as Matt suggests they still serve this purpose but to a lesser extent than if you give them a pull.
I have to admit that we are not that good at remembering to use them, i tend to rank them below a lot of other stuff.  I do make sure that we never have them on for the run so that the mast does not invert or break around them if/when we ease the windward shroud.
Antony

[andyp]

Arh simples!
Thanks that makes sense, I could never work out the difference between what the mast ram did and what the lowers did

[Lukepiewalker]

As stated above, usually lowers downwind, mast ram upwind. The lowers also give you a sideways stiffening effect too. The potential issue with non-adjustabubble lowers is as mentioned, with the adjustable rig if you let off the shrouds and the lowers are still on you can get inversion and potentially even breakage of the mast (especially seeing as the lowers act higher up the mast than the ram/deck.
The key difference with the Cherubim being I don't think they tend to bother with adjustable shrouds, thus this risk is removed.

[Steve (Guest)]

Matt,
I go along with the adjusting theory with a fair amount of purchase, but have to admit that once set for the conditions generally only adjust during racing if the conditions change. Maybe I should let them off more upwind, but I don't use a ram. If you take out your adjusting system and tie them you may find it difficult to re-tie them if the wind suddenly picks up. As you let off the shrouds even if its just the leeward one the mast will move forward and to windward at the top and with the lowers fixed it will straighten the mast in the fore/aft direction and counteract the bend induced by the kickingstrap and leech tension, so you get the affect without tensioning them.
When we first started using them quite a few years ago I know Chris Atkins kept his fixed and just used mast rake to alter the amount of bend in the mast. He also had a mighty screw that fixed the mast at space frame level. I disconnected mine, but kept it there as a pushing only device, probably similar to the way Antony uses the ram, as I felt that having it fixed could end up with it fighting the lowers and putting high stresses in the mast.
On the subject of fixed controls I recall John Holtum telling the story of when he bought March Hare from Mike Jackson and shortly after he told Mike it took him ages to get the siezed kickingstrap winch to free off and work properly. Mike told him that he had lost one of the critical tuning settings as once he had found the right kicking strap position he never adjusted it what ever the conditions or point of sailing.
 
Regards,
 
Steve
N3436  

[John Meadowcroft]

I love the Mike Jackson story.  He also favoured a fixed outhall position and had no spreaders on his mast...
I would love to say that we are following his trend, but we are not.  However on our boat we do not have lowers and just have a mast strut.  To compensate for the absence of lowers we have had the mast sleeved internally to the level of the gooseneck.  Another option, so maybe not too helpful...

[JimC (Guest)]

The key difference with the Cherubim being I don't think they tend to bother with adjustable shrouds, thus this risk is removed.

Also, in my day at least the typical C rig was skiff style with the mast locked to the spreaders, and the control mainly in the top mast.
Provided your lowers are at 90 degrees to the centreline then they shouldn't fight with the fore and aft control and I venture to suggest they probably can be fixed. That's probably the best solution, but may well be constructionally awkward as it means two separate high compression load points at the gunwhales. Logically I would expect that fore and aft adjustment and angled back lowers would mandate adjustment in the lowers.