DAVER1

[adla]

Dave -

Remember way back when we talked about mast changes??? i am in a panic because Steve wants to launch on the 17th...do you have any thoughts about these questions (noone laugh if these appear totally stupid):

if i raise my boom 6 inches - do i have to increase the entire mast size?

will raising the boom affect where the tabernacle should be?

changing the height of the tabernacle...would this allow me to make the birdsmouth mast part out of shorter stock??? (less than 16ft...) obviously the bottom portion will be added to the total height...i just get muddled when i think about the mast..

Thanks,

Adla

[Barry Pyeatt]

Adla,

Don't mean to butt in here since it was directed to Dave, but if you keep the portion of the mast above the gooseneck the same dimensions as plans you can just increase the height of the tabernacle. Everything will work out fine. You will of course need longer shrouds and forestay.

I made my tabernacle 51" and then put a 3" block underneath it with a pair of thin lines that allow me to remove it when I want to. The three inch block is a composite that will allow some moisture to collect in the bottom of the mast box and not have any effect on the bast base itself. If all works as planned, any moisture will drain off thru a weep hole at the base and there will be sufficient space to allow it to dry.

Nothing needs to be larger or oversized to compensate. I made my mast from a 12' 4X4 and the tabernacle from a shorter piece.

[adla]

you're not butting in...i welcome any response to my ???'s...Dave has just been real nice about helping with mast questions and i was just hoping to pick his brain.

i have a 4x4 that is straight and about 5 ft long.... i have some straight 2x12's in the yard that are dry (this is priceless with my time constraints) i have a program that gives me the dimensions of the mast staves for the birdsmouth method (i am not going to taper the mast)...i am just trying to figure out how to do this without having to get different stock...having never built a mast, sailed or anything like that...i want to have my head around the project, so to speak before i get cutting and glueing and wishing i had put the tabernacle 2inches one way or the other or even find out that the mast is not long enough or any other messy variable..

[umop_apisdn]

if you keep the portion of the mast above the gooseneck the same dimensions as plans you can just increase the height of the tabernacle. Everything will work out fine. You will of course need longer shrouds and forestay.

And possibly a taller carport/garage too. :-)

When I rebuilt my tabernacle, I briefly considered making it 4 inches taller as well, until it occurred to me I wouldn't be able to get it into my carport anymore.

Noel

[capt jake]

And possibly a taller carport/garage too.

BINGO! Been there done that. I started to finish installing my mast in my previous 'shop' and realized that I wouldn't be able to get it out of the garage. :shock: I installed it after teh boat was outside. I just finished a new addition to my shop (new place) and spec'd an 8' door. The door company didn't see the need until I shoed them what I was up against.

[Dave R1]

Adla, it's a good thing Barry chimed in. I haven't got much brain to pick.

I think you got some good info. Raising the boom is a good idea for reducing the boom-brain bucket interference. think of whatever height you add to the boom as being added to the bottom of the tabernacle. The distance between the gooseneck and the hardware aloft needs to remain at least the same as in the plans--the luff of the main isn't going to change any.

I added additional length at the top as well to spread all that hardware and the shrouds out but it wouldn't be absolutely required. I like having the space and I prefer the look with a slightly taller mast but that's just me.

Noel makes a good point about raising the boom. There's a corresponding increase in the height at the hinge which may preclude you from putting the boat in a garage. I'm not sure I would be able to get my boat in with the stock tabernacle but I sure can't with what I've got.

Another thing to consider is the attachment point for the forestay. If you are using the stock bowsprit dimensions, make sure that your forestay attachment is correspondingly lower from the top of the mast than the plans say. This will keep the fore triangle the same shape. and keep the jib in the same place.

Of course, you need to consider where the gaff jaws will ride relative to the top of the forestay because you don't want it riding on the eyebolt or mast band. you might want to make sure that the surface is flush on the aft side of the mast so the jaws don't hit the end of an eyebolt or something.

One other thing you might think about is the possibility of making a longer sprit. I did that to maintain the same fore triangle shape (it's a larger triangle but proportioanl to the plans.) and I think it also looks nicer to have the longer sprit with the taller mast. That could be left as a modification after launch and maybe as a "we'll change it later if we feel like it" sort of thing.

I hope all that makes sense and is not too daunting. I believe you'll like having the extra clearance below the boom and you find it is worth it.

Dave

[kydocfrog]

Timely discussion for me.Thanks.

I bought the wood for my mast today. A beautiful piece of clear, tight grained Douglas Fir, 2x8x12 foot with another matching hunk to laminate the lower piece. I'm planning on a four foot base and twelve foot main spar; adding just enough to play with the halyard blocks some. I'm still very seriously considering an older rig; boomless main, a single halyard, and a vang for peak control. The boomless main does keep the center of effort lower without the cranial threat factor.

It is a nice piece of lumber.

DocA

[adla]

assuming i know nothing about rigging and sailing...i lOok at the plans and see that the gooseneck is to be 17" from the deck. i see that the total dimension is 15'1"(i thought it was 16 feet for some reason) i don't see dimensions specifiying (sp) the distance between the gooseneck and whatever else just the dimensions for the hardware at the top. i think i am probably ok making it pretty much to plan (except for the birdsmouth thing) because i wouldn't know one rigging method from another....so my stupid questions really include - raising the tabernacle doesn't negatively effect anything, right? and raising the boom is as easy as a 5" block under the whole deal??? is that what i am reading.

btw...i am pleased to announce that i have gathered my plans and put them in order and in plastic protectors in a notebook...much easier to make sense of them this way..

a.

[Craig]

Alda, I raised the Saralee

[Dave R1]

Adla, unless you want to space things out aloft, you are correect. It is as simple as adding a 5" block under the mast and tabernacle.

The plans do see a bit vague about the distance between the gooseneck and all that stuff above it. You kind of have to infer some of that stuff. The luff of the sail is 9'10" plus you add the thickness of gaff and the height of the throat block above the gaff and add some space for lines and blocks and stuff up there. Or you can just go by the plans and measure down from the top.

Since I also added some length at the top, I basically just spread the stuff out making sure I didn't impinge on the space needed for the mainsail and the gaff. That left me with plenty of room. clearly you don't want the blocks for the throat halyard banging into each other when the main is raised. The line runs easier when the space between blocks is greater because the run is straighter.

As far as figuring shroud and forestay length, you should just be able to attach the shrouds to the mast, raise the mast and see where they meet your turnbuckles. You can use the cable clamps shown in the plans and attach them to an eyebolt also as shown. I made soft eyes (loops in the cable) that slip over the mast and ride on the eyebolt for the peak halyard block. I also made a large eye on which to hang the jib halyard block.

The jib halyard block slips over the mast first, then the forestay, fore starboard shroud, fore port shroud, aft starboard shroud and finally the aft port shroud. It probably isn't critical which order they're done in but that's pretty much the way it is described in The Art of Rigging by George Biddlecombe of the Royal Navy.

[Barry Pyeatt]

I also added 18" to the length of my bowsprit to keep the geometry the same for the stock jib. But adding a roller furling lapper infront of that location. Extra height on the mast makes it 16' 1" on mine. My height difference was primarily to add about 4" to the cabin height and both my son and I are over 6' 1" and figured we needed the little bit of extra clearance. The COE was raised a little but I don't really figure that it will make a significant difference.

[Phil Gowans]

My loosefooted sail was cut just a little different than my prior sail. It brought the boom lower. I decided to raise it this last winter. I did exactly what you suggested, I put a 6" block under the stub mast. This required extending the length of the shrouds and forestay slightly. I made short clip in sections for them. This way I could go back to the prior geometry without anything except taking out the extensions. It has all worked well and a little more headroom is appreciated.

[adla]

well, i cut the mast stub at 53" - intending to widdle some out for the birdsmouth to fit down over (about 2") and make the tabernacle at 51"....so far none of that has to do with the boom...if i raise the boom only, say 4" will it mess up the geometry of the sails? or just the shrouds? (sorry to sound stupid about this but i really haven't a clue about this part of the boat) - i bought the dacron sails, so i don't want to do anything that screws up being able to use them...i am not very tall...seriously about 5'1" is all and wonder if raising the boom is even necessary. As far as speed increase and all - forget it...the boat will go plenty fast for me, i am sure....

here is the stub..

[Barry Pyeatt]

In all reality, if your mast is at the right angle you shouldn't have any issues with the boom being too low. I doubt that you would need to raise it unless you just want more clearance.