Topics

[Amel Yacht Owners] Re: rig tuning

Ryan Meador
 

Steve, thanks for the data, that's very helpful.

Craig, thank you also for your advice.  That's a great rule of thumb.  I have The Complete Rigger's Apprentice, which discusses rig tuning a bit, but not as much as I'd hoped before I bought it.  I will definitely read the booklet you mentioned (which is perhaps this free PDF?).

I suspect the slight looseness in my rig is because the wire has stretched over time.  It was quite tight when I bought the boat, and I think the boat hadn't been sailed much by the previous owner after he replaced the standing rigging.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 12:40 PM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Hi Ryan,

I'd recommend Selden Mast's booklet Hints and Advice on Rig Tuning - you can download the pdf. They give a neat "folding rule" method (pg 32) of determining tension based on the fact that 2 meters of any diameter of 1X19 wire stretches 1mm for each 5% of breaking strength applied.

So, for example, if you want to tension your 12mm cap stays to 20% (Amel tight, maybe!) just tighten them until 2 meters stretches by 4 mm. That stretch will give you about 5600 pounds of tension, as the breaking strength is about 28000.

The Loos gauge doesn't handle wire over 10mm (actually 9.5 mm as it's rated for 3/8) and only goes up to 4500 pounds. That's why the results Nance and Underwood gave Steve Morrison in his post just show "very tight" for his 12mm stays.

After you get a sense for "very tight" you'll get to trust just feeling the stays and being able to judge if they're right. And use Joel's suggestion to go out, sail upwind in a good breeze and see if your lee shrouds are at all slack. If yes, they're way too loose. Oh yeah, and recheck after a while as the wire will stretch over time.

On the headstay there is a turnbuckle screw under the furler. ACMO just calls it "special" , as it's shorter than standard ones so the furler can be closer to the deck.

Have fun tuning!
Craig Briggs SN68 Sangaris


---In amelyachtowners@yahoogroups.com, wrote :


Hi all,

I'm about to embark upon tuning up my rig, which I feel is a little loose, but I'd love some guidance on how to do that.  I've scoured the archives of this list and found many mentions of guides from both Joel Potter and Olivier Beaute, but I haven't been able to find them.  The best guide I've found thus far is this one.   Can anyone link me to the gold standard(s)?

Also, has anyone done the tuning in a more scientific way, with a Loos Gauge?  I'm struggling to understand via qualitative descriptions just how tight is tight.  I think a quantitative measurement would be very helpful.

And finally, how does one adjust the forestay tension?  I admittedly have not studied it in depth, but I didn't see a turnbuckle or any other obvious mechanism.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


Craig Briggs SN 68 Sangaris
 

Hi Steve,
Yep, that's the booklet. Check out the "Folding Rule Method" of tensioning.
Sounds reasonable that the existing rig is loose due to stretch. That makes it pretty easy to tension back up - just count the turns you take on starboard and do the same number on port, assuming the mast is in column to begin with.
Craig SN68 Sangaris, Ft Pierce FL


---In amelyachtowners@..., <ryan.d.meador@...> wrote :

Steve, thanks for the data, that's very helpful.

Craig, thank you also for your advice.  That's a great rule of thumb.  I have The Complete Rigger's Apprentice, which discusses rig tuning a bit, but not as much as I'd hoped before I bought it.  I will definitely read the booklet you mentioned (which is perhaps this free PDF?).

I suspect the slight looseness in my rig is because the wire has stretched over time.  It was quite tight when I bought the boat, and I think the boat hadn't been sailed much by the previous owner after he replaced the standing rigging.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 12:40 PM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Hi Ryan,

I'd recommend Selden Mast's booklet Hints and Advice on Rig Tuning - you can download the pdf. They give a neat "folding rule" method (pg 32) of determining tension based on the fact that 2 meters of any diameter of 1X19 wire stretches 1mm for each 5% of breaking strength applied.

So, for example, if you want to tension your 12mm cap stays to 20% (Amel tight, maybe!) just tighten them until 2 meters stretches by 4 mm. That stretch will give you about 5600 pounds of tension, as the breaking strength is about 28000.

The Loos gauge doesn't handle wire over 10mm (actually 9.5 mm as it's rated for 3/8) and only goes up to 4500 pounds. That's why the results Nance and Underwood gave Steve Morrison in his post just show "very tight" for his 12mm stays.

After you get a sense for "very tight" you'll get to trust just feeling the stays and being able to judge if they're right. And use Joel's suggestion to go out, sail upwind in a good breeze and see if your lee shrouds are at all slack. If yes, they're way too loose. Oh yeah, and recheck after a while as the wire will stretch over time.

On the headstay there is a turnbuckle screw under the furler. ACMO just calls it "special" , as it's shorter than standard ones so the furler can be closer to the deck.

Have fun tuning!
Craig Briggs SN68 Sangaris


---In amelyachtowners@yahoogroups. com, <ryan.d.meador@...> wrote :


Hi all,

I'm about to embark upon tuning up my rig, which I feel is a little loose, but I'd love some guidance on how to do that.  I've scoured the archives of this list and found many mentions of guides from both Joel Potter and Olivier Beaute, but I haven't been able to find them.  The best guide I've found thus far is this one.   Can anyone link me to the gold standard(s)?

Also, has anyone done the tuning in a more scientific way, with a Loos Gauge?  I'm struggling to understand via qualitative descriptions just how tight is tight.  I think a quantitative measurement would be very helpful.

And finally, how does one adjust the forestay tension?  I admittedly have not studied it in depth, but I didn't see a turnbuckle or any other obvious mechanism.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


Ryan Meador
 

I tackled this problem yesterday, and it did not go as planned.  My main mast is now pumping fore-and-aft in a wide range of wind speeds with the wind on the beam (I haven't been able to test any other wind directions yet).  The top of the mast seems to stay still, and there is little to no motion at the lower spreaders; the pumping is centered near the upper spreaders.

Before starting, I reviewed advice from this list, the Selden guide, Brion Toss's Rigger's Apprentice, Ivar Dedekam's Illustrated Sail and Rig Tuning, and other online sources.  I thought I had a vague idea of what I was doing.  Unfortunately, every one of those guides assumes you're starting from a freshly-stepped mast, so I had to improvise to apply the procedure to tune mine in-place (I couldn't use the folding-rule method because the stays were already under an unknown load).  Here's what I did:

  1. removed a slight forward tilt of the uppermost part of the main by tightening the backstay, which, as I suspected going in, was the loosest of all the stays -- the previous owner installed the radar on a Questus backstay mount.  I will probably put the radar back in its traditional place when I next unstep the mast.  I did not adjust the forestay.
  2. removed a slight lateral S curve
    1. tightened the starboard cap shroud
    2. the port intermediate shroud
    3. the starboard lowers
  3. I tightened all four lowers one turn just because they all seemed a bit looser than what was described on this list (they now make a sort of tone when hit with a wooden hammer handle, but they don't quite resonate)
  4. tightened mizzen starboard cap shroud one turn to correct slight bend to port
  5. tightened all four mizzen lowers one turn because they seemed loose
  6. loosened port mizzen backstay half a turn.  I know the backstays are supposed to be fairly loose and the port was a bit tighter than the starboard one
The masts were now in column and looked just about perfect.  When the pumping first became apparent (when the weather turned, of course), I added a turn to the main's forward lowers in an attempt to induce a minuscule pre-bend.  There was no perceptible difference in the mast shape, but there may have been a minor difference in the amount of pumping.

Does anyone have experience with this problem?  I'd greatly appreciate some advice on how to fix it!  I'm almost desperate enough to try a non-Amel-familiar professional rigger.

Thanks,
Ryan and Kelly
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 6:25 PM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Hi Steve,

Yep, that's the booklet. Check out the "Folding Rule Method" of tensioning.
Sounds reasonable that the existing rig is loose due to stretch. That makes it pretty easy to tension back up - just count the turns you take on starboard and do the same number on port, assuming the mast is in column to begin with.
Craig SN68 Sangaris, Ft Pierce FL


---In amelyachtowners@yahoogroups.com, wrote :

Steve, thanks for the data, that's very helpful.

Craig, thank you also for your advice.  That's a great rule of thumb.  I have The Complete Rigger's Apprentice, which discusses rig tuning a bit, but not as much as I'd hoped before I bought it.  I will definitely read the booklet you mentioned (which is perhaps this free PDF?).

I suspect the slight looseness in my rig is because the wire has stretched over time.  It was quite tight when I bought the boat, and I think the boat hadn't been sailed much by the previous owner after he replaced the standing rigging.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 12:40 PM, sangaris@... [amelyachtowners] <amelyachtowners@yahoogroups.com> wrote:
 

Hi Ryan,

I'd recommend Selden Mast's booklet Hints and Advice on Rig Tuning - you can download the pdf. They give a neat "folding rule" method (pg 32) of determining tension based on the fact that 2 meters of any diameter of 1X19 wire stretches 1mm for each 5% of breaking strength applied.

So, for example, if you want to tension your 12mm cap stays to 20% (Amel tight, maybe!) just tighten them until 2 meters stretches by 4 mm. That stretch will give you about 5600 pounds of tension, as the breaking strength is about 28000.

The Loos gauge doesn't handle wire over 10mm (actually 9.5 mm as it's rated for 3/8) and only goes up to 4500 pounds. That's why the results Nance and Underwood gave Steve Morrison in his post just show "very tight" for his 12mm stays.

After you get a sense for "very tight" you'll get to trust just feeling the stays and being able to judge if they're right. And use Joel's suggestion to go out, sail upwind in a good breeze and see if your lee shrouds are at all slack. If yes, they're way too loose. Oh yeah, and recheck after a while as the wire will stretch over time.

On the headstay there is a turnbuckle screw under the furler. ACMO just calls it "special" , as it's shorter than standard ones so the furler can be closer to the deck.

Have fun tuning!
Craig Briggs SN68 Sangaris


---In amelyachtowners@yahoogroups. com, wrote :


Hi all,

I'm about to embark upon tuning up my rig, which I feel is a little loose, but I'd love some guidance on how to do that.  I've scoured the archives of this list and found many mentions of guides from both Joel Potter and Olivier Beaute, but I haven't been able to find them.  The best guide I've found thus far is this one.   Can anyone link me to the gold standard(s)?

Also, has anyone done the tuning in a more scientific way, with a Loos Gauge?  I'm struggling to understand via qualitative descriptions just how tight is tight.  I think a quantitative measurement would be very helpful.

And finally, how does one adjust the forestay tension?  I admittedly have not studied it in depth, but I didn't see a turnbuckle or any other obvious mechanism.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA



eric freedman
 

Derick Gates
 

I had my rig replaced by Caraibe Greement in Le Marin, Martinique, in January, 2017, using ACMO rigging that I had purchased and had sent to the Amel office in Le Marin. Gaetan Rivet runs the rigging shop there. Gaetan’s riggers measured the tension of each stay with an instrument that clamped onto the wires and tried to bend them. In that way they achieved the correct tension for each stay and the tension was properly balanced all around. Don’t ask me for the tension measurements - I don’t know what they were. I will not however that the new rigging was extremely tight, and that includes the mizzen back stays which were much tighter than I had ever had them before.

I returned to Le Marin in January 2018 and received the free “tuneup” that Gaetan had promised I could have when the rig was initially installed. In the intervening year the rig had stretched a few millimeters and was “too loose” according to Caraib Greement. They said this is normal, and they retightened the whole rig. They also said I should not expect any further stretching of the stays.

Perhaps Gaetan Rivet could be prevailed upon to reveal what tension he puts each stay under. I think that Amel might have this information at hand too.

Note that the length of each set of stays needs to be kept constant port vs starboard, not just the tension. Thus the set of turnbuckles on each side for a particular stay should look like they have the same number of turns on them as the tension is adjusted.

Derick Gates
SM2K #400
Brava
Currently on the hard in Antigua

Ryan Meador
 

Hi Eric,

Thank you for the advice. That's my plan whenever I unstep the masts. I'm sure there is a dead spot in the radar, but every other Amel seems to get by with it. I'd rather not have the weight on the backstay.

I don't think that is the cause of my present problem, though. Now that I've tightened the backstay, the radar doesn't move at all. I don't think it is contributing to the pumping. Certainly, Frank had it tuned such that it wasn't a problem, so it's possible.

Thanks,

Ryan and Kelly
SM 233 Iteration
Boston, MA, USA

On May 27, 2018 3:36 PM, "eric kimberlite@... [amelyachtowners]" <amelyachtowners@...> wrote:
 


Hi Ryan,
I would ask Questus if they can sell you the Questus mast mounting kit for the Questus. Mine has been working fine on the Mizzen mast for 16 years.

Frank mounted the dome on the backstay as he said he gets a dead spot behind the mast on the radar. I thought his mount as odd.

Amel rigging is ridiculously tight the cap stay is like a piece of rebar.
Good luck with your rig tuning.
Fair winds,
Eric


On Sun, May 27, 2018 at 10:15 AM, Ryan Meador ryan.d.meador@... [amelyachtowners] wrote:

 

I tackled this problem yesterday, and it did not go as planned.  My main mast is now pumping fore-and-aft in a wide range of wind speeds with the wind on the beam (I haven't been able to test any other wind directions yet).  The top of the mast seems to stay still, and there is little to no motion at the lower spreaders; the pumping is centered near the upper spreaders.

Before starting, I reviewed advice from this list, the Selden guide, Brion Toss's Rigger's Apprentice, Ivar Dedekam's Illustrated Sail and Rig Tuning, and other online sources.  I thought I had a vague idea of what I was doing..  Unfortunately, every one of those guides assumes you're starting from a freshly-stepped mast, so I had to improvise to apply the procedure to tune mine in-place (I couldn't use the folding-rule method because the stays were already under an unknown load).  Here's what I did:

  1. removed a slight forward tilt of the uppermost part of the main by tightening the backstay, which, as I suspected going in, was the loosest of all the stays -- the previous owner installed the radar on a Questus backstay mount.  I will probably put the radar back in its traditional place when I next unstep the mast.  I did not adjust the forestay.
  2. removed a slight lateral S curve
    1. tightened the starboard cap shroud
    2. the port intermediate shroud
    3. the starboard lowers
  3. I tightened all four lowers one turn just because they all seemed a bit looser than what was described on this list (they now make a sort of tone when hit with a wooden hammer handle, but they don't quite resonate)
  4. tightened mizzen starboard cap shroud one turn to correct slight bend to port
  5. tightened all four mizzen lowers one turn because they seemed loose
  6. loosened port mizzen backstay half a turn.  I know the backstays are supposed to be fairly loose and the port was a bit tighter than the starboard one
The masts were now in column and looked just about perfect.  When the pumping first became apparent (when the weather turned, of course), I added a turn to the main's forward lowers in an attempt to induce a minuscule pre-bend.  There was no perceptible difference in the mast shape, but there may have been a minor difference in the amount of pumping.

Does anyone have experience with this problem?  I'd greatly appreciate some advice on how to fix it!  I'm almost desperate enough to try a non-Amel-familiar professional rigger.

Thanks,
Ryan and Kelly
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 6:25 PM, sangaris@... [amelyachtowners] <amelyachtowners@yahoogroups..com> wrote:
 

Hi Steve,

Yep, that's the booklet. Check out the "Folding Rule Method" of tensioning.
Sounds reasonable that the existing rig is loose due to stretch. That makes it pretty easy to tension back up - just count the turns you take on starboard and do the same number on port, assuming the mast is in column to begin with.
Craig SN68 Sangaris, Ft Pierce FL


---In amelyachtowners@..., wrote :

Steve, thanks for the data, that's very helpful.

Craig, thank you also for your advice.  That's a great rule of thumb.  I have The Complete Rigger's Apprentice, which discusses rig tuning a bit, but not as much as I'd hoped before I bought it.  I will definitely read the booklet you mentioned (which is perhaps this free PDF?).

I suspect the slight looseness in my rig is because the wire has stretched over time..  It was quite tight when I bought the boat, and I think the boat hadn't been sailed much by the previous owner after he replaced the standing rigging.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA


On Wed, May 16, 2018 at 12:40 PM, sangaris@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Hi Ryan,

I'd recommend Selden Mast's booklet Hints and Advice on Rig Tuning - you can download the pdf. They give a neat "folding rule" method (pg 32) of determining tension based on the fact that 2 meters of any diameter of 1X19 wire stretches 1mm for each 5% of breaking strength applied.

So, for example, if you want to tension your 12mm cap stays to 20% (Amel tight, maybe!) just tighten them until 2 meters stretches by 4 mm. That stretch will give you about 5600 pounds of tension, as the breaking strength is about 28000.

The Loos gauge doesn't handle wire over 10mm (actually 9.5 mm as it's rated for 3/8) and only goes up to 4500 pounds. That's why the results Nance and Underwood gave Steve Morrison in his post just show "very tight" for his 12mm stays.

After you get a sense for "very tight" you'll get to trust just feeling the stays and being able to judge if they're right. And use Joel's suggestion to go out, sail upwind in a good breeze and see if your lee shrouds are at all slack. If yes, they're way too loose. Oh yeah, and recheck after a while as the wire will stretch over time.

On the headstay there is a turnbuckle screw under the furler. ACMO just calls it "special" , as it's shorter than standard ones so the furler can be closer to the deck.

Have fun tuning!
Craig Briggs SN68 Sangaris


---In amelyachtowners@yahoogroups. com, wrote :


Hi all,

I'm about to embark upon tuning up my rig, which I feel is a little loose, but I'd love some guidance on how to do that.  I've scoured the archives of this list and found many mentions of guides from both Joel Potter and Olivier Beaute, but I haven't been able to find them.  The best guide I've found thus far is this one.   Can anyone link me to the gold standard(s)?

Also, has anyone done the tuning in a more scientific way, with a Loos Gauge?  I'm struggling to understand via qualitative descriptions just how tight is tight.  I think a quantitative measurement would be very helpful.

And finally, how does one adjust the forestay tension?  I admittedly have not studied it in depth, but I didn't see a turnbuckle or any other obvious mechanism.

Thanks,
Ryan
SM 233 Iteration
Boston, MA, USA




greatketch@...
 

Ryan,

Some thoughts.  

I have never been able to tune a rig accurately “by ear”.  I always use a loos tension gauge, or the stretch method with the meter stick.  But... that only gets you so far.  

Taking the boat out sailing in a good breeze is a very important part of the process.  Skipping that step, out of economic requirements, is why so many “Professional” riggers come up short in tuning rigs, and not just Amels. 

Olivier has written an excellent summary on tuning that is here in the archives.  The is no reason you can’t slack all the rigging and start as if your mast was newly stepped.  

If your back stay was too loose, then your forestay must be too, assuming the mast is straight, since they pull in opposition to each other.

Bill Kinney
Sm160, Harmonie
Norfolk, VA, USA


Ryan Meador
 

Hi Bill,

Thanks for the info.  I really don't want to try to slack all my rigging and start from scratch.  I'm not sure I'm strong enough to get it back tight again, and I also don't trust that the mast won't fall over while it's loose.  I need to find a professional.  I haven't been able to find Olivier's rig tuning guide, unless it's the one I linked in my first post, but I don't think it is.

I did end up tightening my forestay to no avail.  In a windy rain storm late at night.  It changed the frequency of the pumping, but didn't eliminate it.  I'm not convinced it was necessary or even a good idea, since the mast did have a slight bend forward before I started tightening the backstay.  Also, now the forestay turnbuckle only has about one more turn of adjustment left in it before it bottoms out.

Thanks,
Ryan and Kelly
SM 233 Iteration
Boston, MA, USA



On Mon, May 28, 2018 at 8:08 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Ryan,


Some thoughts.  

I have never been able to tune a rig accurately “by ear”.  I always use a loos tension gauge, or the stretch method with the meter stick.  But... that only gets you so far.  

Taking the boat out sailing in a good breeze is a very important part of the process.  Skipping that step, out of economic requirements, is why so many “Professional” riggers come up short in tuning rigs, and not just Amels. 

Olivier has written an excellent summary on tuning that is here in the archives.  The is no reason you can’t slack all the rigging and start as if your mast was newly stepped.  

If your back stay was too loose, then your forestay must be too, assuming the mast is straight, since they pull in opposition to each other.

Bill Kinney
Sm160, Harmonie
Norfolk, VA, USA



greatketch@...
 

Ryan (and everybody else)

The one thing I hate about this forum host is the totally AWFUL search capabilities it has.  It took a bit of digging to find, but here is the link to the rigging procedure that Olivier posted. It is really helpful, and makes things really clear.  There are several things in the initial set up that are going to be unique to the precision that Amel used in building these boats, but the final tensioning is pretty much the way I always handled any boat.


If you have an Amel to which this procedure relates, do what I just did and SAVE this link, and print it out for future reference.

Bill Kinney
SM160, Harmonie
Norfolk, VA, USA

Ryan Meador
 

Thank you for finding that, Bill!  It sounds like I will need to slack all my rigging and start from scratch, which I think will necessitate a professional.  Olivier has also graciously agreed to come visit my boat and take a look, which I'm sure will teach me a lot.

Thanks,
Ryan and Kelly
SM 233 Iteration
Boston, MA, USA



On Tue, May 29, 2018 at 8:01 PM, greatketch@... [amelyachtowners] <amelyachtowners@...> wrote:
 

Ryan (and everybody else)


The one thing I hate about this forum host is the totally AWFUL search capabilities it has.  It took a bit of digging to find, but here is the link to the rigging procedure that Olivier posted. It is really helpful, and makes things really clear.  There are several things in the initial set up that are going to be unique to the precision that Amel used in building these boats, but the final tensioning is pretty much the way I always handled any boat.


If you have an Amel to which this procedure relates, do what I just did and SAVE this link, and print it out for future reference.

Bill Kinney
SM160, Harmonie
Norfolk, VA, USA


scentstone
 

Thank you Bill
After some search, here it on this forum https://amelyachtowners.groups.io/g/main/message/26665
Kind regards
Fred
S/V ScentStone
SM2K #375
La Rochelle, France