Hello, if any of you fellow mac owners have any experience with changing out their stainless standing rigging to synthetic I would greatly appreciate any advice or info that you could pass along. MY stainless rigging is in need of replacing & I would like to learn more about the specific synthetic material used,the price per ft or meter of just the material, the diameter needed for the mac 25 & whether or not the veneers would have to be replaced with turnbuckles for adjusting the stretch. Thanks in advance for any info !!
Synthetic standing rigging for a mac 25
- Thread starter whudatt
- Start date
I replaced my lifelines with Dyneema, but standing rigging is another affair. Do you have any experience working with shrouds and stays? Have you familiarized yourself with the choices and capacities of the synthetic options? If not, I think you should consult a local rigger who knows the difference between the way steel cable and Dyneema behave, knows what hardware will work, and whether anything other than tried-and-true steel cable is even advisable.
Just for your information, you'll not save any money replacing wire with synthetic products. The issue that you seemed concerned with is the cost of the connectors. But......... there are less expensive ways to attach wire...as long as you aren't "fashion" conscious.
Look for shops online that make stuff for macs. They'll often make common parts in large batches to bring costs down. A local rigger quoted me 750. D and R marine was about 550 at the time
Thank you for your reply ! Did they replace your standing rigging with synthetic line like I am asking information about ?
I'm not sure if you're asking me but I'm still wondering why you want to go with synthetic over the tried and true stainless steel rigging? The cost is about the same but there are far more variables to consider
I had a local rigger match pricing similar to what I found online. It was steel lines and new turnbuckles
Thank you for your reply. I do have some experience with ss standing rigging, I rigged & swagged the last set on my boat, but no experience with the synthetic,heat set lines that have been gaining popularity over the last 20 years,so much so that the insurance companies have jumped on board (providing it is installed professionally) I have not familiarized myself with the choices & capacities of the synthetic options & that was the purpose of my post on the matter. I have read several posts on this forum on this subject but they are mostly 10 to 15 years old & I know that the synthetic line companies such as Samsons & Dyneema have progressed since then in regards to synthetic lines replacing standing ss shrouds & stays. I will share with you what I have read on this matter. I do realize that ss rigging is tried & true but from everything that I have read the synthetic lines are gaining popularity, especially on the smaller,trailerable boats such as my M25 because, diameter for diameter, the right synthetic line such as Samson's Amsteel Blue, Samson's Amsteel AS-78 or Dyneema's DM20 is stronger than 1x19 ss cable, breaking point is 4,200lbs for 3/16" versus 5,400lbs for the 3/16" Amsteel AS-78 ,1/7th the weight of ss & it is said to be easily eye spliced plus there are no hidden corrosion spots, such as behind the swaged ferrules on the ss, plus the synthetic lines are easily stored without worry of kinking them. also spare lines can be easily spliced & stored onboard just incase of a shroud or stay failure on the water,tough to swage a ferrule onboard ! The cons with the synthetic lines are stretch,chafing & cost.I read that all three of these pre mentioned lines are pre shrunk & heat set which will reduce the inevitable stretch,just as ss stretches & has to be tuned occasionally. Another factor mentioned about reducing stretch is that you can increase the diameter of the shrouds & stays by one size which will help reduce the stretch, so In my case I would go up to 3/16" from 5/32". Chafing, these lines either have a protective casing or are coated with a protective product called Samthane but as in the case with ss you always have to keep an eye out for friction spots.Last but not least,pricing, the only one that I have been able to get pricing info on so far for 3/16"Amsteel AS -78 is online through Vela & is 90 cents per ft without shipping costs included so since I live in Mexico that could be a factor since I am retired & on a fixed income. Taking these pros & cons into consideration I have to seriously consider the synthetic route ! I am basically looking for someone that has done this modification recently that can relate the experiences they had doing it & also if they had to change their adjusting veneers to turnbuckles because of the stretch factor. Thank you for your thoughts on this matter & I hope this answers your question as to why I am considering doing this. Another thing about the ss lines,maybe it's just me but looking at a 25ft Macgregor with it's mast lowered & all of the ss cables running every which way compared to what it looks like with the mast raised & under sail is to me like a pig wallering in the mud to a beautiful,graceful Swan gliding across the water, Jus' Sayn' !!
Nice to know you've done your homework. Not evident from the initial post.
My original advice stands. Consult a local rigger.
Thanks again for your suggestion about seeking the advice of a rigging company but there aren't any in the area where I live in Mexico.Would you happen to know of any in your area that i could email for rigging advice ? My thinking was that of the 36,000 Macgregor boats out there that someone on this forum might have more current info regarding experience with synthetic rigging, maybe in a few days someone will see it & offer their advice !
Thanks for your reply, it is definitely something to consider! Which Dyneema line were you consider using & how long ago was that ?
I can see you dilema. Our local rigging guy is good, but old school, and I am not sure if he has any experience/knowledge with Dyneema. I will ask next time I see him at the marina.
That was 2013 and I don’t remember the exact product… I was looking at breaking strength … the Mac 22 standing rigging was not that substantial to begin with and so the weight diff was less than 25 pounds… didn’t seem worth the trouble or money then… I got SS wire rope from tractor supply and used SS wire nuts to terminate.
the M22 has a lot lighter mast than the 25. You may come up with a diff decision …
the M22 has a lot lighter mast than the 25. You may come up with a diff decision …
Thanks again for the reply ! in regards to the M22 & the M25 both masts are 28ft long so I suspect that the shroud & stay diameters would be the same 5/32". I suspect that there has been considerable progress made in synthetic lines since 2013 so I am hoping that someone on this forum who has done this modification recently will offer some advice. Thanks again !
I've done a fair bit (OK, an unreasonable amount) of thinking about this; considering synthetic for the next set of standing rigging on our C-22 and/or a future 25-footer if we ever upsize (probably with a practice run on our 15-foot daysailer). So I'm interested in this discussion. FWIW: I'd consider synthetic for some of the same reasons as the OP
Here are a few bits I've gleaned (caveat: I haven't actually tried synthetic rigging yet, and I'm certainly not a professional rigger - so I'm not an authority by any measure).
Dyneema and Spectra - these are two brand names of the sam(ish) Ultra High Weight Polyethylene fibers. There are other brand names too.
Bend Radius
Testing seems to indicate that an eye splice around a terminator needs a radius of at least 2x the line diameter (e.g. 1/4" for 1/8" Dyneema or 5/16" for 5/32"). That seems like a sharp bend, but recall that this is for an eye, where we have 2 legs sharing the load.
There are (at least) two kinds of stretch to watch out for:
Thermal Expansion
Dyneema is odd, in that it has a negative thermal expansion coefficient (TEC). Unlike most materials we're familiar with, it gets shorter when hot and longer when cold. So some sailors with synthetic rigs note that they're loose in the (cooler) morning, and tight in the (hot) afternoon. YMMV.
A few sources always worth listening to - unlike me
- To save a little weight (specifically mast raising / lowering - any weight saves there help with rigging / derigging safety)
- No kinks when the mast is stored or while trailering
- Because it's cool to think about
Here are a few bits I've gleaned (caveat: I haven't actually tried synthetic rigging yet, and I'm certainly not a professional rigger - so I'm not an authority by any measure).
Dyneema and Spectra - these are two brand names of the sam(ish) Ultra High Weight Polyethylene fibers. There are other brand names too.
Bend Radius
Testing seems to indicate that an eye splice around a terminator needs a radius of at least 2x the line diameter (e.g. 1/4" for 1/8" Dyneema or 5/16" for 5/32"). That seems like a sharp bend, but recall that this is for an eye, where we have 2 legs sharing the load.
- Colligo's connectors are really conservative here - something like 5x or more.
- Blue Wave has their own line, which look worth considering.
There are (at least) two kinds of stretch to watch out for:
- Construction Elongation - the fibers and splices settling in when first put under tension. It might take awhile (hours maybe, but not weeks?) but it's a one-time stretch.
- To deal with this, you'll want to stretch your shrouds after splicing and before installation. I have a 3500-lb 2-speed winch I plan to mount to my solid workbench (with blocks on each end) to make a rigging table with repeatable tension. (You can always stretch by anchoring to a tree and your trailer hitch and driving away, but that's not very repeatable).
- Creep - Dyneema fibers enlongate slowly over time when under constant load - creep might reach a noticable amount over a period of weeks or months, but not over hours (so you'd never notice it in running rigging, but definitely do in standing rigging).
- Here, we do several things:
- Use heat-treated fibers like SK99 and DM20, which have much lower creep. FisheriesSupply carries Marlow Excel D12 Max (SK99), but only in 100m spools (they might cut to order if you ask). DM20 is the lowest creep I'm aware of, but not widely available in small diameters appropriate for our little trailer sailers. JimmyGreen in the UK stocks D12 M-Rig Max (DM20); if anyone knows of another source, I'm all ears.
- Upsize from your default rigging size, so the standing rigging sits at a lower percentage of absolute breaking strength
- Allow some way to take up the slack over time - lashings (e.g. with Colligo's lashing terminators or turnbuckles with sufficient travel.
- Here, we do several things:
Thermal Expansion
Dyneema is odd, in that it has a negative thermal expansion coefficient (TEC). Unlike most materials we're familiar with, it gets shorter when hot and longer when cold. So some sailors with synthetic rigs note that they're loose in the (cooler) morning, and tight in the (hot) afternoon. YMMV.
A few sources always worth listening to - unlike me
- Brion Toss (deceased)
- Evans Starzinger : Still active on SailingAnarchy.
- Julian Bethwaite has done a fair amount of work on synthetic rigs for 49ers and International 14's. Also active on SA.
I ran into him yesterday, and he says he does not have any experience with anything other than SS cable. Sorry.
Good morning & I thank you for the information & the references that you posted ! I am looking at Samson Ropes Amsteel AS-78 for my M25's upper & lower shrouds. I have sent an email to them asking if this can be used for standing rigging but I haven't heard back from them yet,maybe I'll try calling them today. The recommended product that specifies use for standing rigging is Colligo Dux but from what I understand it is $4 per ft(plus shipping to Mexico, which would be another arm & leg) I am retired on a fixed income so this product is out of the question for me.If Samson replies back to me saying that the Amsteel AS-78 is ok to use then Vela Sail has it advertised online for $.90 per ft which is affordable for me but I am still trying to find out if they ship to Mexico & how much that would cost. I'll post the findings when I find out everything. Two more pluses about the synthetics are that it is much easier to eye splice synthetic than swaging ss wire rope so it could be done onboard on the water & it rolls up & stores onboard easily so carrying spares is less awkward than ss. Thanks again !!I've done a fair bit (OK, an unreasonable amount) of thinking about this; considering synthetic for the next set of standing rigging on our C-22 and/or a future 25-footer if we ever upsize (probably with a practice run on our 15-foot daysailer). So I'm interested in this discussion. FWIW: I'd consider synthetic for some of the same reasons as the OP
(Note that cost savings is not a significant factor here, as you'll see when you look at terminators)
- To save a little weight (specifically mast raising / lowering - any weight saves there help with rigging / derigging safety)
- No kinks when the mast is stored or while trailering
- Because it's cool to think about
Here are a few bits I've gleaned (caveat: I haven't actually tried synthetic rigging yet, and I'm certainly not a professional rigger - so I'm not an authority by any measure).
Dyneema and Spectra - these are two brand names of the sam(ish) Ultra High Weight Polyethylene fibers. There are other brand names too.
Bend Radius
Testing seems to indicate that an eye splice around a terminator needs a radius of at least 2x the line diameter (e.g. 1/4" for 1/8" Dyneema or 5/16" for 5/32"). That seems like a sharp bend, but recall that this is for an eye, where we have 2 legs sharing the load.
Strech
- Colligo's connectors are really conservative here - something like 5x or more.
- Blue Wave has their own line, which look worth considering.
There are (at least) two kinds of stretch to watch out for:
If I do this, I would likely use 5/32" DM20 (if I can find it) or SK99 to replace my 1/8" SS, and use turnbuckles - on a trailer sailer, my rig is only up for a few weeks per year, so I think creep would be manageable with turnbuckles.
- Construction Elongation - the fibers and splices settling in when first put under tension. It might take awhile (hours maybe, but not weeks?) but it's a one-time stretch.
- To deal with this, you'll want to stretch your shrouds after splicing and before installation. I have a 3500-lb 2-speed winch I plan to mount to my solid workbench (with blocks on each end) to make a rigging table with repeatable tension. (You can always stretch by anchoring to a tree and your trailer hitch and driving away, but that's not very repeatable).
- Creep - Dyneema fibers enlongate slowly over time when under constant load - creep might reach a noticable amount over a period of weeks or months, but not over hours (so you'd never notice it in running rigging, but definitely do in standing rigging).
- Here, we do several things:
- Use heat-treated fibers like SK99 and DM20, which have much lower creep. FisheriesSupply carries Marlow Excel D12 Max (SK99), but only in 100m spools (they might cut to order if you ask). DM20 is the lowest creep I'm aware of, but not widely available in small diameters appropriate for our little trailer sailers. JimmyGreen in the UK stocks D12 M-Rig Max (DM20); if anyone knows of another source, I'm all ears.
- Upsize from your default rigging size, so the standing rigging sits at a lower percentage of absolute breaking strength
- Allow some way to take up the slack over time - lashings (e.g. with Colligo's lashing terminators or turnbuckles with sufficient travel.
Thermal Expansion
Dyneema is odd, in that it has a negative thermal expansion coefficient (TEC). Unlike most materials we're familiar with, it gets shorter when hot and longer when cold. So some sailors with synthetic rigs note that they're loose in the (cooler) morning, and tight in the (hot) afternoon. YMMV.
A few sources always worth listening to - unlike me
- Brion Toss (deceased)
- Evans Starzinger : Still active on SailingAnarchy.
- Julian Bethwaite has done a fair amount of work on synthetic rigs for 49ers and International 14's. Also active on SA.