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Unjury-rigging a jury-rigged 470

TakK

New Member
Hello

I bought an old 470 from 1976 (built by Roga) but from what I can work out, the previous owner must have got been using it jury-rigged. The rudder was on facing the wrong way for a start... I'm struggling to work out how to get it properly rigged and I'm seeking your help. I know I'm not the first one to stumble into this forum with similar problems.

I'd previously owned a couple of Lasers so I thought 470s should be fairly simple and standard (like Lasers). But I was wrong.

The 470 is to take the kids out sailing and get them trapezing. I sailed a 470 from the late 80s (which didn't have a spinnaker or many of the controls) quite a lot when I was a kid so I have fond memories of it. If they take to sailing, I'll probably swap it within 2-3 years for an Optimist, a day boat or whatever takes their fancy. My aim isn't to restore the 470 to top notch shape but to get it to a point I can sail it without it falling apart so I'm looking to spend as little as I can get away with and with fairly minimal effort. I want to keep it simple and minimal because the kids are going to be crewing. To start with, I'm not going to bother with the spinnaker.

I've attached som photos with labels. Do you know what the numbered items might be for?

Slides 2-3: Securing and tensioning the main and jib halyards is, currently, my biggest problem. There's a rusty Magic Box for the jib halyard that should probably come off but could still be used. There's also a dual toothed rack riveted on top of the Magic Box. Presumably the Main Halyard used to hook on to it? What would be a good solution? There are various mystery brackets and blocks.

Slide 4: I've made a guess at what the eyes on the deck around the mast might be but do you know what they're for? What are the various cleats for? I expected more eyes around the front of the cockpit to guide the elastic for the trapeze. How is it usually done?

Slide 5: Lots of mystery cleats around the traveller.

Slide 6: It's a Proctor mast; probably from the 70s. I'm not sure it's a 470 mast though. I can't work out how to attach the hooks from the trapeze wire to the mast. Surely it doesn't go into the riveted hole where the shrouds are attached?

Slide 7: The boom end is hacked with a block on a bent shroud plate. I guess it'll do for now.

I welcome your suggestions and thanks in advance.

Tak
 

Attachments

LaLi

Well-Known Member
Slides 2-3: Securing and tensioning the main and jib halyards is, currently, my biggest problem. There's a rusty Magic Box for the jib halyard that should probably come off but could still be used. There's also a dual toothed rack riveted on top of the Magic Box. Presumably the Main Halyard used to hook on to it? What would be a good solution? There are various mystery brackets and blocks.
There really should be a hook at the top set of sheaves of the magic box. Seeing that it's a wire that comes out of the other end, there must be plenty of friction inside, and it's doubtful if the box actually contributes much to halyard tension :confused: You may have to dismantle and clean it and then see if it's functional. Is the jib halyard itself entirely of rope? If so, that's totally opposite to what you should have...
The rack may very well be for the main halyard. Is there an exit hole for it somewhere higher up? There is a yellow line that goes into the mast at the top, is it the same one that comes out near the mast foot?
1: not for the cunningham, nor for anything else I can think of.
2: blocks. Probably turning blocks for whatever runs through 7 and 8.
3: could be for the vang/kicker. The 45-degree eyestraps above it definitely are, and the double block could be for leading the tails of the vang control line aft. A mast-cleated vang is no good in a 470. It needs to be led aft and double-ended to the helm. I don't see those side-tank cleats in any of the pictures - are they actually there?
4: could be for the cunningham. May have replaced a block on the mast, like the ones on the port side (screwhole visible).
5: could be for anything. Vang, jib halyard?

Slide 4: I've made a guess at what the eyes on the deck around the mast might be but do you know what they're for? What are the various cleats for? I expected more eyes around the front of the cockpit to guide the elastic for the trapeze. How is it usually done?
6 through 8: the centre lead (7) is definitely for the spinnaker pole downhaul. The other two are possibly for external pole uphaul and spinnaker halyard. Are those two external or internal on the mast? Cunningham is also possible but not likely (runs directly from the sail to the mast step area).
9: these are most likely for the pole uphaul and cunningham.
The jib tracks are interesting. Is there really only a sideways pinstop adjustment? What are the Clamcleats next to them for?
The trapeze elastic fairleads are a little too close to the gunwale (typical in the 1970s). They would be better approximately where the mystery Clamcleats are. From there, a modern way to lead the elastic would be to blocks in the mast step area (the "5" eyestrap for example) and back along and around the centreboard case.

Slide 5: Lots of mystery cleats around the traveller.
10: those are indeed for the spinnaker sheet.
11: that is where that spinnaker sheet comes from 10. It then crosses the cockpit to the corresponding block on the other side.
12: that is a cleat for the spinnaker guy(windward sheet) - the line runs through it on its way from 10 to 11. The idea is that it cleats/uncleats automatically depending which direction you pull the line through 11.
13: doesn't look broken. May be intended for a lead for or deadending an elastic, such as the one for the spinnaker pole downhaul.
14 & 15: the other is likely for the jib halyard, and the other remains a mystery...
16: this is likely for the spinnaker halyard (it's usually on the port side).

Slide 6: It's a Proctor mast; probably from the 70s. I'm not sure it's a 470 mast though. I can't work out how to attach the hooks from the trapeze wire to the mast. Surely it doesn't go into the riveted hole where the shrouds are attached?
The serial number ends in "78", but that may not be the year, as I think the golden colour points to the early 1970s. It's a 470 mast if it's the right length and all the fittings are in the right place - measure for instance the height of the spinnaker pole ring: if it's around 1250 mm, then you have the real thing. If not, then you have a big job ahead :oops:
The trapeze wires are from a newer mast, probably a Z-Spar. It looks like you could attach the J-hooks to the pins on the shroud fittings (which no doubt are intended for the trapezes), but if not, an additional shackle + tape should work as an interim setup. But chances are that the wires are too long (that was the style at the time), so you have more work ahead anyway. Attach them and let's see what the other end looks like.
17 is a fitting for a burgee/wind indicator.
By the way, the forestay attachment location looks odd, it should be at the same level as the shrouds. Not that it matters, but strange anyway. (Where's the spinnaker halyard block?)

Slide 7: The boom end is hacked with a block on a bent shroud plate. I guess it'll do for now.
No problem if the cleat holds. Could change to a small aluminium Clamcleat near the forward end of the boom and a little thicker line, though, so it's actually adjustable.

_
 

TakK

New Member
Thanks so much LaLi. That's explained a lot. I'll update the pictures with your suggested labels later when I've worked most of it out.

Magic Box & jib halyard:
There really should be a hook at the top set of sheaves of the magic box. Seeing that it's a wire that comes out of the other end, there must be plenty of friction inside, and it's doubtful if the box actually contributes much to halyard tension :confused: You may have to dismantle and clean it and then see if it's functional.
The Magic Box does move but it's a bit of a grind. It's probably less work in the long-run to make up a rig tensioner made up of free floating blocks like on a MacKay 420 you suggested in a previous post. In that photo of the MacKay system, the bottom triple block has a cleat on it. Why's that? Shouldn't the rig tensioner line go aft and cleated at #14?

I'm thinking that the starboard side of the double block #3 might be for the rig tensioner?

Is the jib halyard itself entirely of rope?
Unfortunately so. It also seems to cause a lot of friction when raising the main so I should replace it with a wire halyard. I'll replace it in the winter after some more sailing.

Main halyard:
The rack may very well be for the main halyard. Is there an exit hole for it somewhere higher up? There is a yellow line that goes into the mast at the top, is it the same one that comes out near the mast foot?
1: not for the cunningham, nor for anything else I can think of.
There's no exit hole for the main halyard above the rack. The yellow line in the mast is the main halyard and at the moment, it comes out at the bottom of the mast. Maybe the main halyard was led out of the mast just above the Magic Box, then hooked to the rack? Not a very nice arrangement and I thought that it had to be a wire loop to hook on to the rack (it's all rope in this case)?

Could the main halyard exit at the bottom of the mast through the port-side block #3 at the bottom of the mast then up to the #1 Clamcleat on the port-side of the mast?

Kicking strap/vang:
3: could be for the vang/kicker. The 45-degree eyestraps above it definitely are, and the double block could be for leading the tails of the vang control line aft. A mast-cleated vang is no good in a 470. It needs to be led aft and double-ended to the helm. I don't see those side-tank cleats in any of the pictures - are they actually there?
No, I don't see cleats on the side tank that could be for the vang. Could cleat #15 on the port side of the centreboard casing have been meant for the vang?

Cunningham:
4: could be for the cunningham. May have replaced a block on the mast, like the ones on the port side (screwhole visible).
Maybe we're missing a block and cleat for the cunningham. Still to be worked out...

Jib tracks:
The jib tracks are interesting. Is there really only a sideways pinstop adjustment? What are the Clamcleats next to them for?
I do find the wooden tracks charming. Yeap, only this adjustments. I'm not sure what the clamcleats next to the tracks are for. A bit strange but maybe the elastic for the trapeze went through it? Not sure why you'd do that.

Spinnaker sheets & halyard:
10: those are indeed for the spinnaker sheet.
11: that is where that spinnaker sheet comes from 10. It then crosses the cockpit to the corresponding block on the other side.
12: that is a cleat for the spinnaker guy(windward sheet) - the line runs through it on its way from 10 to 11. The idea is that it cleats/uncleats automatically depending which direction you pull the line through 11.
16: this is likely for the spinnaker halyard (it's usually on the port side).
Blocks & cleats for the spinnaker sheets/guy makes sense. Thanks.

13: doesn't look broken. May be intended for a lead for or deadending an elastic, such as the one for the spinnaker pole downhaul.
Thanks.

#16 Block on port side of the centreboard casing = Spinnaker halyard. Makes sense. In that case...

6 through 8: the centre lead (7) is definitely for the spinnaker pole downhaul. The other two are possibly for external pole uphaul and spinnaker halyard. Are those two external or internal on the mast? Cunningham is also possible but not likely (runs directly from the sail to the mast step area).
Could the spinnaker halyard go through #8 (eye on the port side of the deck around the mast as you suggest), round #2 on the port side of the mast, which look like two blocks with the plate in the middle snapped? Then along the port side of the centreboard casing to cleat #16?

Spinnaker pole up/downhaul:
Maybe the flimsy block #4 at the bottom of the mast on the starboard side is for the pole uphaul and there should another on the starboard side for the downhaul?

9: these are most likely for the pole uphaul and cunningham.
13: doesn't look broken. May be intended for a lead for or deadending an elastic, such as the one for the spinnaker pole downhaul.
Could the clamcleats #9 on top of the centreboard housing be for pole up & down haul? Or is the downhaul not a line but an elastic dead-ended at #13?

Mast:
The serial number ends in "78", but that may not be the year, as I think the golden colour points to the early 1970s. It's a 470 mast if it's the right length and all the fittings are in the right place - measure for instance the height of the spinnaker pole ring: if it's around 1250 mm, then you have the real thing. If not, then you have a big job ahead
Uh-oh. I'll measure it up.

By the way, the forestay attachment location looks odd, it should be at the same level as the shrouds. Not that it matters, but strange anyway. (Where's the spinnaker halyard block?
I wonder if this is a sign that it's not a genuine 470 mast.... The spinnaker halyard block is missing - where should it be?

Trapeze:
The trapeze wires are from a newer mast, probably a Z-Spar. It looks like you could attach the J-hooks to the pins on the shroud fittings (which no doubt are intended for the trapezes), but if not, an additional shackle + tape should work as an interim setup. But chances are that the wires are too long (that was the style at the time), so you have more work ahead anyway. Attach them and let's see what the other end looks like.
I wasn't sure about hooking the J-hooks to the other pin on the shroud fitting because I was worried that it would stress the fitting open when you go out on the trapeze. Hooking the J-hooks to a shackle on the shroud fitting sounds like a risky interim solution. I'll check the length first and then consider the next step.

The trapeze elastic fairleads are a little too close to the gunwale (typical in the 1970s). They would be better approximately where the mystery Clamcleats are. From there, a modern way to lead the elastic would be to blocks in the mast step area (the "5" eyestrap for example) and back along and around the centreboard case.
Thanks.

Boom/outhaul:
No problem if the cleat holds. Could change to a small aluminium Clamcleat near the forward end of the boom and a little thicker line, though, so it's actually adjustable.
That's a good idea. Another one for the winter.
 

LaLi

Well-Known Member
Magic Box & jib halyard:

It's probably less work in the long-run to make up a rig tensioner made up of free floating blocks like on a MacKay 420 you suggested in a previous post. In that photo of the MacKay system, the bottom triple block has a cleat on it. Why's that? Shouldn't the rig tensioner line go aft and cleated at #14?

I'm thinking that the starboard side of the double block #3 might be for the rig tensioner?

[the jib halyard] also seems to cause a lot of friction when raising the main so I should replace it with a wire halyard. I'll replace it in the winter after some more sailing.
It doesn't matter much where the jib halyard is cleated as you don't adjust it on the water (unless you're a top racer, that is). An "integrated" cleat means that there is one separate part less, but if you already have plenty of cleats to lead a line to, then you of course use one of those.

The numerous blocks in the mast step area, including the double block at the mast foot, can be used for anything. You want first to figure out what you want to do with each system, and if you can use existing fittings, fine. Don't worry too much about finding a function for every single part.

The jib halyard should be wire because it holds the whole rig up while sailing, and should be able to take 100+ kg worth of static tension without stretching noticeably. Some very good (=expensive) rope might do, but as you've noticed, it's a bit risky running one inside the mast.

Main halyard:

There's no exit hole for the main halyard above the rack. The yellow line in the mast is the main halyard and at the moment, it comes out at the bottom of the mast. Maybe the main halyard was led out of the mast just above the Magic Box, then hooked to the rack? Not a very nice arrangement and I thought that it had to be a wire loop to hook on to the rack (it's all rope in this case)?

Could the main halyard exit at the bottom of the mast through the port-side block #3 at the bottom of the mast then up to the #1 Clamcleat on the port-side of the mast?
The rack is there definitely for a wire but if there's no corresponding exit, then it remains a mystery. A rope main halyard is ok if it's good quality. You can take it to the Clamcleat but it's going to slip if that cleat is plastic (looks like it is). A similar aluminium cleat should be fine.

Kicking strap/vang:

I don't see cleats on the side tank that could be for the vang. Could cleat #15 on the port side of the centreboard casing have been meant for the vang?
If there are no cleats for the vang on the side tanks near the traveller, then it was most likely cleated on top of the centreboard case... or maybe to the Clamcleats by the jib tracks? (Now that would be a pretty neat system actually :) )

Cunningham:

Maybe we're missing a block and cleat for the cunningham.
There seem to be plenty of cleats to choose from, and you can always add a block or two of that "flimsy" kind to the mast step if needed.

Jib tracks:

I'm not sure what the clamcleats next to the tracks are for. A bit strange but maybe the elastic for the trapeze went through it?
They may have been for a now-discarded system for adjusting the jib lead height. which was common in the 1970s. But they definitely have nothing to do with the trapeze system.

Spinnaker sheets & halyard:

Could the spinnaker halyard go through #8 (eye on the port side of the deck around the mast as you suggest), round #2 on the port side of the mast, which look like two blocks with the plate in the middle snapped? Then along the port side of the centreboard casing to cleat #16?
In one word, yes. I'd also add a lead block behind the cleat so you can pull in any direction.

Spinnaker pole up/downhaul:
Maybe the flimsy block #4 at the bottom of the mast on the starboard side is for the pole uphaul and there should another on the starboard side for the downhaul?

Could the clamcleats #9 on top of the centreboard housing be for pole up & down haul? Or is the downhaul not a line but an elastic dead-ended at #13?
The pole downhaul wasn't adjusted in those days and you don't really need to. It's good enough that it has a stopper that keeps the pole from skying, and a take-up elastic.

The more I think of it, the case-top ("9") cleats were intended for the vang and cunningham, and 14 or 15 for the pole uphaul.

Mast:

The spinnaker halyard block is missing - where should it be?
About 15 cm above the shrouds. I might as well list here the heights of the essential mast fittings & features (all in millimetres, measured from the lowest point on the heel fitting) so you can check them:

Lower point - min boom upper edge height; roughly the height of the gooseneck (depends on the fitting designs) - 1055 max
Spinnaker pole ring - 1240 to 1260
Spreaders - 2790 to 2810
Spinnaker pole uphaul turning block - free but usually a bit above the spreaders
Jib halyard - 4870 max
Trapeze - 4910 to 5110
Shrouds and forestay - 4995 to 5025
Spinnaker halyard - 5170 max
Upper point - mainsail head max height - 5750 max from the lower point

Trapeze:

I wasn't sure about hooking the J-hooks to the other pin on the shroud fitting because I was worried that it would stress the fitting open when you go out on the trapeze. Hooking the J-hooks to a shackle on the shroud fitting sounds like a risky interim solution. I'll check the length first and then consider the next step.
That second pin on the shroud attachment plates is clearly intended for the trapeze so I wouldn't worry about it. You'll have less than 100 kg of load on the wires, which also the smallest shackles can take.

No worries :D

_
 

TakK

New Member
Thanks LaLi. I think I've got the picture now. Just some details to work out and then I'll order the bits and try it out. I took the boat out today and I really do enjoy how 470s handle—even with a very floppy jib halyard.

Jib halyard:
It doesn't matter much where the jib halyard is cleated as you don't adjust it on the water (unless you're a top racer, that is). An "integrated" cleat means that there is one separate part less,
Cleat integrated into the rig tensioner on the mast (to replace the Magic Box) does sound simpler. I'll go for that. For this, I'm thinking about re-purposing the 4:1 vang like the concept in the photo below (obviously with the Magic Box removed). The fiddle blocks take up space in length and quite chunky but worth a try? It's only 4:1 but with my crew hanging off the forestay (and probably not making much difference because he's only 9), maybe I'll get just enough tension?
jib_halyard_concept_470.jpg

BTW, when I remove the Magic Box off the mast, is it structurally sound to just leave the open holes or do they need to be riveted?

Main Halyard:
You can take it to the Clamcleat but it's going to slip if that cleat is plastic (looks like it is). A similar aluminium cleat should be fine.
An arrangement like below seems to work. Yeap, it's a plastic Clamcleat. I'm concerned that the main halyard could be knocked out of an open Clamcleat like this so I'm thinking about replacing it with a traditional horn cleat. How are the halyard lines normally stowed away on a 470 so that they don't go everywhere?

main_halyard_470.jpg


Mystery Clamcleat next to jib track:
70s_jib_track_470.jpg
If there are no cleats for the vang on the side tanks near the traveller, then it was most likely cleated on top of the centreboard case... or maybe to the Clamcleats by the jib tracks? (Now that would be a pretty neat system actually :) )
That would also be quite neat.

They may have been for a now-discarded system for adjusting the jib lead height. which was common in the 1970s.
That's an interesting historical footnote. Though it's an interesting piece of 470 archaeology, I'll take up your earlier advice and remove them and move the fairlead for the trapeze there.

Numerous mystery blocks and cleats:
The numerous blocks in the mast step area, including the double block at the mast foot, can be used for anything. You want first to figure out what you want to do with each system, and if you can use existing fittings, fine. Don't worry too much about finding a function for every single part.
That's good advice. Thanks.

Vang:
The more I think of it, the case-top ("9") cleats were intended for the vang and cunningham, and 14 or 15 for the pole uphaul.
That makes sense. Gives easy access to the vang and cunningham.

I've been sketching up various vang system. I'm going to go for a single-ended vang to keep it simple (I don't have the cleats on the tank for a double-ended system any way). In another post, you advised that the standard vang for 470s is a double-ended 16:1 system (2x2x4) but that you've used 12:1 (3x4 and 3x2x2) before. I was thinking about a 12:1 vang (6x2) like the #5 drawing from Ronstan but you advised that it gets a bit crowded round the mast? Isn't a cascaded system (like 3x2x2) get into a tangle and a bit more work when rigging up? You also mentioned that a 6:1 system might be good enough for recreational use (that sounds like me).

Out of interest, do you prefer the 3x4 or 3x2x2 system?

I'm thinking about a 12:1 system (6x2) like what I've sketched below. The block at the bottom that forms part of the 6:1 system makes use of the #3 blocks near the bottom of the mast. The block on the boom that's part of the 2:1 system is repurposed from the block that was originally on the Magic Box. What do you think?
Vang_idea1.jpg

Mast measurements:
Spinnaker pole ring - 1240 to 1260
I measured the height from the mast foot to the spinnaker pole ring: 1240mm. Phew. There's still hope that it might be a 470 mast. I'll tackle the other measurements next time I'm at the sailing club.


It's all coming together. Thanks!
 

TakK

New Member
LaLi—Thanks for the mast measurements; it's highlighted a big mix up on this boat.

As you can see on the photo below, I think the forestay has been attached higher than it should be to where the spinnaker halyard should go. This explains why the forestay is under so much tension (it came with some shackles to lengthen it and even then the mast looks like it leans forward in an unrigged state).
470_jib_halyard_forestay.jpg

By the way, the forestay attachment location looks odd, it should be at the same level as the shrouds. Not that it matters, but strange anyway. (Where's the spinnaker halyard block?)
Your earlier intuition was right. I think the forestay should have clipped on to the clevis pin just above where the jib halyard (red line) comes out.

Even with this corrected, the jib halyard, shroud and forestay seems to be out of spec [my values are in square brackets]. I probably got the measurements right to within 5-10mm as it was a solo job with a 3-metre tape measure (must buy a longer one):

  • Lower point - min boom upper edge height; roughly the height of the gooseneck (depends on the fitting designs) - 1055 max [1055mm when at height shown in photo]
  • Spinnaker pole ring - 1240 to 1260 [1240mm]
  • Spreaders - 2790 to 2810 [2795mm]
  • Spinnaker pole uphaul turning block - free but usually a bit above the spreaders [750mm above spreaders]
  • Jib halyard - 4870 max [4945mm: 75mm too high]
  • Trapeze - 4910 to 5110 [same as shrouds: 4960mm]
  • Shrouds and forestay - 4995 to 5025
    • [Shroud 4960mm: 35mm too low]
    • [Forestay 4945mm: 50mm too low]
  • Spinnaker halyard - 5170 max [5140mm]
  • Upper point - mainsail head max height - 5750 max from the lower point [5630mm from gooseneck]
  • [Mast length 6870mm]
I guess this suggests that it's not a genuine 470 mast but it should be good enough for recreational sailing and friendly club sailing.

Trapeze:
I was a bit sceptical about your suggestion about hooking the trapeze off a shackle and taping it. Actually, one side had a shackle (photo on right) so it looks like it was previously done like that. I could also hook it on the clevis pin like in the left side photo but I'm worried it'll put too much side ways force on the plate. For the proper solution, I'm thinking about putting a D-shackle and making up a new wire with a ferrule spliced loop.
470_trapeze_fitting.jpg

The length of the trapeze looks ok but the position of the elastic could get in the way of my eccentric wooden jib tracks. I'll give it a try and see how things go.
470_gooseneck_trapeze_handle.jpg
 

LaLi

Well-Known Member
I took the boat out today and I really do enjoy how 470s handle—even with a very floppy jib halyard.
Oh, you already sailed it! Good if it felt nice, although it sounds like it was heavily out of tune... I've been thinking of writing a general tuning page for everyone to read; it's that people who first get to this type of boats (including Laser 2s) tend to think that there's not much to adjusting the rig. Well, to get it properly tuned (even for "recreational" sailing!) takes hours of measuring and adjusting, because of the lack of standardization.
Anyway, at this point just see to that the mast foot is in the right place - it looks like it's very far back, which is somehow typical for old boats. Measure the distance from the transom to the aft edge of the mast: around 3100 mm is what most use today, 3055 being the absolute minimum. We'll get to rake and tension when you have a working jib halyard :rolleyes:


Jib halyard:

Cleat integrated into the rig tensioner on the mast (to replace the Magic Box) does sound simpler. I'll go for that. For this, I'm thinking about re-purposing the 4:1 vang like the concept in the photo below (obviously with the Magic Box removed). The fiddle blocks take up space in length and quite chunky but worth a try? It's only 4:1 but with my crew hanging off the forestay (and probably not making much difference because he's only 9), maybe I'll get just enough tension?

BTW, when I remove the Magic Box off the mast, is it structurally sound to just leave the open holes or do they need to be riveted?
I think cleat at the back end of the centreboard case is simpler because it's already there :D
I was actually looking at that vang earlier and thought of using it for the jib halyard along the centreboard case. But I think it would be best to just replace the magic box with two triple blocks, and take the line via the mast step to 15. That would be a 7:1, but of course hanging on the forestay helps...

All fastening holes do weaken the mast of course, but once they're drilled, it doesn't structurally matter anymore whether there is a rivet or screw there or not.


Main Halyard:

An arrangement like below seems to work. Yeap, it's a plastic Clamcleat. I'm concerned that the main halyard could be knocked out of an open Clamcleat like this so I'm thinking about replacing it with a traditional horn cleat. How are the halyard lines normally stowed away on a 470 so that they don't go everywhere?
Clamcleats are by their nature "sticky" and don't get knocked open very easily, at least if there is any tension on the line. Just switch to a similar aluminium cleat which won't slip. I'd be more concerned about that white small block ("2") which wasn't intended for that... maybe better to use the port block "3" after all.
The halyard tails are stowed in spinnaker bags :rolleyes: The starboard bag is usually empty anyway, and most bags have extra pockets as well for this purpose.

By the way: looking at these pictures... do you have a hatch for that opening in the main bulkhead (just forward of the mast)? And if not, is that round hatch for the forward bulkhead definitely watertight?


Mystery Clamcleat next to jib track:

Though it's an interesting piece of 470 archaeology, I'll take up your earlier advice and remove them and move the fairlead for the trapeze there.
Ok, fine. You'll eventually need some sort of vertical adjustment for the jib lead, though, even if it's just a piece of rope tied between the lead block and the track. As for the track itself, you'll keep it in the innermost position at all times. They're a fine museum piece (I'd keep them myself!), but no good for jib trim.


Vang:

I've been sketching up various vang system. I'm going to go for a single-ended vang to keep it simple (I don't have the cleats on the tank for a double-ended system any way). In another post, you advised that the standard vang for 470s is a double-ended 16:1 system (2x2x4) but that you've used 12:1 (3x4 and 3x2x2) before. I was thinking about a 12:1 vang (6x2) like the #5 drawing from Ronstan but you advised that it gets a bit crowded round the mast? Isn't a cascaded system (like 3x2x2) get into a tangle and a bit more work when rigging up? You also mentioned that a 6:1 system might be good enough for recreational use (that sounds like me).

Out of interest, do you prefer the 3x4 or 3x2x2 system?

I'm thinking about a 12:1 system (6x2) like what I've sketched below. The block at the bottom that forms part of the 6:1 system makes use of the #3 blocks near the bottom of the mast. The block on the boom that's part of the 2:1 system is repurposed from the block that was originally on the Magic Box. What do you think?
Cascades may get tangled when loose (the modern Laser vang is a classic) but I wouldn't consider it a problem really. Multiple blocks are more of a complicating factor.
I don't think I've ever suggested a 6:1 vang for a 470... you probably mix this with the jib halyard :rolleyes:

3x4 is my sentimental favourite as I designed it myself a long time ago :D Most of the fleet here had a 3x2x2 at the time, which has one sheave less, but needs to be dimensioned more accurately so that there's enough range of adjustment. Both are good. For the last 20 years at least, everyone's had the 16:1, though. I personally think it's a bit of overkill.

The sketch looks fine, but don't lead the line directly to the mast step area - it'll hit the centreboard case, and you'll also get lead problems with the "3" block when the boom swings out to the side. Take it instead first to the mast to whatever you have on the lower eyestrap, and then down to 3.

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LaLi

Well-Known Member
I think the forestay has been attached higher than it should be to where the spinnaker halyard should go. This explains why the forestay is under so much tension (it came with some shackles to lengthen it and even then the mast looks like it leans forward in an unrigged state).

Your earlier intuition was right. I think the forestay should have clipped on to the clevis pin just above where the jib halyard (red line) comes out.
The forestay position doesn't really matter, as I said earlier. The 470 forestay is only a rigging help and a safety device. It should be under no tension whatsoever when the jib is up. (And the shrouds should be loose when the jib is down.) It should be the maximum length and that's it.
What to do: 1) measure the mast foot position (like I said in the previous message), and move it if necessary, 2) take all the extra shackles off the forestay, and replace them with a piece of rope (at least for now), 3) adjust the length of the rope so that the mast comes not more than halfway out of the mast gate (that's the definition of max length). The mast should rake back quite a bit then. You can tie an elastic along the length of said rope to take the slack out when the jib is up. If you want, you can later change the rope to a wire of the same length.

the jib halyard, shroud and forestay seems to be out of spec.
I guess this suggests that it's not a genuine 470 mast but it should be good enough for recreational sailing and friendly club sailing.
The measurements don't all quite match, so it wasn't class-specific originally. Makes one think, what was it originally then? The pole fitting and spreaders are lower on the 470 than in other comparable boats, but they're just "right" on this mast for the 470, and there are no signs of old mounting holes. All one can say it's at least a few years older than the hull, and a mystery :confused: But the bottom line is, you can tune it like a 470 mast and fly 470 sails on it. You obviously agree that that's what counts.

Trapeze:
I was a bit sceptical about your suggestion about hooking the trapeze off a shackle and taping it. Actually, one side had a shackle (photo on right) so it looks like it was previously done like that. I could also hook it on the clevis pin like in the left side photo but I'm worried it'll put too much side ways force on the plate. For the proper solution, I'm thinking about putting a D-shackle and making up a new wire with a ferrule spliced loop.

The length of the trapeze looks ok but the position of the elastic could get in the way of my eccentric wooden jib tracks.
As expected, the handle looks like it's on the low side, and the wire quite long :rolleyes: Pull the wire tight along the mast: the handle should be above the gooseneck. My personal favourite height is nearly halfway to the pole ring (from the gooseneck), so that would be like 1130 mm up. (If you want to customize this for children, we can talk more about that later.) Depending how much you can/need to shorten them, you can probably redo the upper attachment with the existing wires. I'm still not concerned about any sideways forces, but I understand you want something else than a "jury rig".
By the way, the proper place to tie the elastic to that type of trapeze ring is to the part between the circular and elongated halves. All the associated fittings look fine.

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TakK

New Member
I've been thinking of writing a general tuning page for everyone to read; it's that people who first get to this type of boats (including Laser 2s) tend to think that there's not much to adjusting the rig. Well, to get it properly tuned (even for "recreational" sailing!) takes hours of measuring and adjusting, because of the lack of standardization.
That'll be really handy.

Anyway, at this point just see to that the mast foot is in the right place - it looks like it's very far back, which is somehow typical for old boats. Measure the distance from the transom to the aft edge of the mast: around 3100 mm is what most use today, 3055 being the absolute minimum.
I'd moved the mast a little forward since the photo was taken. I'll measure it properly.

By the way: looking at these pictures... do you have a hatch for that opening in the main bulkhead (just forward of the mast)? And if not, is that round hatch for the forward bulkhead definitely watertight?
Ah, you've got sharp eyes. Yes, it's one of things that makes me a bit nervous. No, the seams of the big round plywood on the bulkhead is not very watertight and I've been thinking what to do about it: Just fix it up a bit better or make up a proper GRP piece with a hatch like:

hatches.jpg

You'll eventually need some sort of vertical adjustment for the jib lead, though, even if it's just a piece of rope tied between the lead block and the track. As for the track itself, you'll keep it in the innermost position at all times.
Hmmm. Another one for the next season.

Thanks for the tips & ideas. I'll order the parts and get to work in a couple of weeks' time.
 
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