470 Layout

LaLi

Well-Known Member
#61
I think the vang is supposed to run off of the metal strap on the lower, rear of the mast (the one that the inadequate vang is hooked into in the pictures). Connecting the vang at the mast step allows it to interfere with the front centerboard trunk.
I meant that the secondary vang line should run first from the boom to the mast, then down to the mast step. It will hit the centreboard case (the forward "lip" of it) if you lead it back directly from the mast. As I also said, the aft exit blocks are at an angle that doesn't point directly to the mast fitting. Are there by any chance any existing blocks or fairleads between the mast step and the exit blocks, possibly in the vicinity of the thwart? (That would explain a couple of things. Post pictures if you find anything.)

I'm going to try setting up the new jib purchase system to the existing I hook on the mast, rather than to the mast step.

It remains to be seen if this setup will allow enough room for proper tensioning of the jib, however.
I've been thinking that ever since I noticed that fitting. As your cleat block has a swivel, an additional shackle is all you need to attach it there.

You're right that the range of adjustment has to be tested "live"; it depends totally on the length of the halyard wire, so be ready to shorten it, or get a longer one. But at that point you're already doing basic tuning, so measure the mast foot position before that. Also, it helps if your forestay is the maximum length, that is, it barely keeps the widest part of the mast within the mast gate, with the mast foot in the right place.

What do you recommend for line for my jib sheets (both type and diameter) and the same for my spinnaker sheets?
For the spinnaker sheet, anything 6 mm thick that has a Dyneema core and isn't awfully stiff. The jibsheet could be a 6 or 7 mm polyester rope, but as your jib cleats are on the windward side (and you have to hand-hold the sheet a lot), some very soft 8 mm might work better.

Note that I used the singular for both sheets: a continuous spinnaker sheet is standard, and the smartest (I think) way of tying the jibsheet to the sail is with a piece of thinner rope in the middle of a continuous line.

At this point, I think I'll post this picture of a 2005-ish Mackay which illustrates this, and quite a few other things, too :rolleyes:

470.jpg.9b9e4a97072b572d610905546e0db44b.jpg

You can see the spinnaker sheet (white line with green fleck) crossing the cockpit, and the yellow jibsheet tied to the jib clew with a purple line (which I think should be shorter).

(And no, I don't know what the green handles are for. And yes, you do need spinnaker bags like those.)

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#64
After seeing that, I will stick with my Laser/ILCA Dinghy...
:)
Haha, Wavedancer, I hear ya!!! Though I always did admire the 470s, they perform well with the right skipper, but I reckon one can say that about any boat, LOL. Moi, I like the minimalist approach, keeping things streamlined and operating under the *KISS* Principle: "KEEP IT SIMPLE, STUPID!!!" :rolleyes:
 
Thread starter #67
Alright, so, I have been away from my boat rigging for the last couple of weeks. In the meantime, I have purchased a bunch of line and am returning to the running rigging again. I have found a way to attach my laser-style connector to the boom vang. The Jarken 093 was too big to fit my new 029 Harken block so I used this setup instead.
Vang boom connection.jpg
Not as elegant as the U Adapter but serviceable. I'm still looking for an elegant way to attach my new vang to the fitting on the mast. Perhaps a small enough twisted shackle is what I need.
Twisted shackle.jpg
Also, I am trying to figure out the routing of the line through the blocks of the vang. I have been using the picture that was posted earlier but I'm not certain of the details. I assume that there will be two ends of line coming out of the setup for cleating, is that correct?
 

LaLi

Well-Known Member
#69
The 093 too big for the 29 mm blocks? Should have tried it first before suggesting, sorry. (Everything has to be tested in real life.) But as I said, the swivel is pointless here, and you might want to use tape or thin elastic to keep the block from swiveling. The multi-part cascade will be a mess anyway at times (ask any Laser sailor).

The mast attachment: depends on the block. But it's always good to have plenty of small but strong shackles, both straight and twisted, available. You will need more of them than you think.

But as stated before, your problem at the mast end of the vang is that the eyestrap on the mast is above the level of the centreboard case top. You absolutely need to lead the line also via the mast step, and/or attach a second eyestrap on the mast below the original. And yes, there will be a vang line running on both sides of the case to the exit blocks right in front of the traveller. If there's only one system on a 470 that you want to be double-ended it's the vang.

I've been looking for good layout pictures for a while, and of course some of the best are to be found on this very forum :D

I thought of posting this one just to show how the centreboard uphaul (yellow in this boat) and downhaul (black) lines are led across the cockpit these days. But you can see some of the vang arrangement as well:

IMG_1198.JPG

Of course, no one ever takes pictures of the mat step area! (Or it's in the dark.) But you can still see here that all parts of the vang lead just below the case top level from the boom. Also visible are the vang tails (red in this boat) coming out of the exit blocks to the cleats on the side tank.

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Thread starter #70
I've been looking for good layout pictures for a while, and of course some of the best are to be found on this very forum
Yes, indeed. I hope that this very long set of posts will be useful to others. I'll post all of my eventual set up in great detail as well, including the mast step and with no dark areas.
 
Thread starter #71
But as stated before, your problem at the mast end of the vang is that the eyestrap on the mast is above the level of the centreboard case top. You absolutely need to lead the line also via the mast step, and/or attach a second eyestrap on the mast below the original.
OK, I wish I could see an example of what you are saying here. Sorry for not fully picturing what you mean in my mind's eye. The way I was picturing the vang attachment was with my triple 16mm block hooked onto the big eyestrap on the mast (the attachment point that is, as you say, above the centerboard trunk). Is the attachment at the mast step that you are mentioning one of the line ends being tied off down there?
 

LaLi

Well-Known Member
#72
Well, no, the non-moving ends of the primary vang lines have to be attached high enough on the mast in order to not hit the centreboard case. It's the ends of the cleating line that should be led through some lower point such as the mast step, after they exit your triple block. Adding a second attachment point to the mast would make things clearer.

I try to find/post pictures/diagrams in a few days. I'd do the photography myself, but the class is inactive here and I don't know where they've put all the boats :D

Have you measured your mast foot position yet? :rolleyes:

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Thread starter #73
Measure the distance from the transom to the aft edge of the mast. The spar should stand at 90° to the mast gate (just for this measurement!), and you should include the mainsail track, as if it came all the way down where it's actually cut off now below the boom. The reading should be about 3095 millimetres. Chances are that the mast foot is farther back (smaller number) than that now. This is also part of the basic tuning; your sails may be some very old cut which may have used settings very different from the modern ones, but I still think that is the best figure to use as a starting point.
Hello, I'm finally getting back to this rigging project after having been torn away with other, less interesting work.

I'm not sure about this measurement that you mention, here. I get the measurement from the transom to the aft part of the mast (3095mm), but what does the main sail track have to do with the measurement? Also, am I sticking a nice, big carpenter's square on the deck to check that the mast is perpendicular?

I got my new Ronstan I beam from APS and took the old bent one out (I can't imagine how that got bent!). I now have to cut it to length and drill some new holes in the correct spots but the beam shape does fit, thankfully. A pain in the rear end to get the hardware off!

I'm still waiting for a few hardware pieces to finally get my boom vang rigged up but that should be done this week.

I will have to switch to fixing some running rigging problems on our racing boat (a flying scot) this weekend but I'm sure that I'll have a bunch more questions in the coming days regarding the 470.
 

LaLi

Well-Known Member
#74
I get the measurement from the transom to the aft part of the mast (3095mm), but what does the main sail track have to do with the measurement?
Your mast is an Elvström, which has the sail track cut away below the boom. The measurement is done as if the track continued all the way down (it's a class rule), so you need to subtract the track depth from the measured transom-to-mast distance.

am I sticking a nice, big carpenter's square on the deck to check that the mast is perpendicular?
If you absolutely want to :D But it's not really that accurate - the purpose of the measurement is to ensure that you're not totally off the scale. The 3095 mm is actually a number that I remember using for a former club boat years ago. The current North tuning guides give similar values; 3100 would probably be easier to remember. The class rule maximum is 3115.

Chances are that you want to move the mast foot forward on the step, but we don't know that yet.

I got my new Ronstan I beam from APS and took the old bent one out (I can't imagine how that got bent!). I now have to cut it to length and drill some new holes in the correct spots but the beam shape does fit, thankfully.
Cool! Have you thought about keeping the vintage single-car system vs. changing to a bridle? (The track has to be there even if there's nothing "travelling" on it.)

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Thread starter #75
Your mast is an Elvström, which has the sail track cut away below the boom. The measurement is done as if the track continued all the way down (it's a class rule), so you need to subtract the track depth from the measured transom-to-mast distance.
OK, I see the sail track section extending below the boom below the boom.
Sail Track below the boom.jpg

...and I have this measurement (approximately 3060mm) from the transome to the aft edge of the mast, along the centerboard trunk.

Measurement from Transome.jpg
Measurement From Transome 2.jpg
...oops, that's really blurry.

So, am I subtracting the little bit of sail track below the boom from the measure ment I made (3060mm)? Am I getting this correct? If so, this is looking like my mast needs to move forward. The boom is pretty close to perpendicular withe the deck surface, as measured with a square.
 

LaLi

Well-Known Member
#76
You measure how much the sail track protrudes (horizontally) from the mast (some 20 mm, maybe), and subtract that from the 3060 mm. But your mast really appears to be :eek: illegally far back! The minimum is 3055.

The next thing to do: move the mast to the forwardmost hole in the step and measure again.

(This is actually interesting. It looks like the whole fitting is farther back than on later boats.)

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