# Bronze vs Stainless steel



## killarney_sailor (May 4, 2006)

Thought I would start a new thread rather than burying this in the thread about losing a toggle at the head of the forestay since it might be general inters. The old toggle was bronze and the new one is stainless. In fact, you don't see many chromed bronze fittings anymore. Is this mainly a result of cost or are today's stainless fittings just better than bronze ones would be?

An aside, when I bought my boat it had bronze split pins. They were wonderful to work with and could be reused quite easily. I was going to buy new ones when the ones I had wore out - until I saw the price. I now have stainless pins instead.


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## ccriders (Jul 8, 2006)

I would think bronze is still the gold standard for turnbuckles. While they can turn green, I don't think they will suffer from crevice corrosion. Plus bronze is less brittle/more flexible which should extend its life cycle over stainless (but be specific about which stainless).
I recently paid $20 for two 3/8 X 3 inch flathead machine bolts with washers and nuts. Stainless would have been 1/4 the cost, but they are holding a bronze grudgeon in place.
John


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## aloof (Dec 21, 2014)

A bronze turnbuckle, especially the body, is the gold standard. $$


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## SloopJonB (Jun 6, 2011)

Lots of bronze stuff from Roman days 2000 years ago and longer has been brought up from the bottom of the Med in conditions from recognizable to very good.

Haven't heard about any comparable S/S pieces.


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## souljour2000 (Jul 8, 2008)

There are better students of metallurgy in SN than I ...who may add to the discussion hopefully... but to answer your question IMHO it is indeed "cost-driven"bottom-line issues and yet more pronounced it is perhaps more a lack of commitment to quality that exists today in most areas of mass-production...and consumers who quietly accept the crap foisted on them when they would rather have something decent and of quality for a couple bucks more but it's not even offered usually by the retailer/manufacturer...unless you want to hunt down and order from some small marine foundry supplier in New England, the northwest USA or northern Europe...


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## Classic30 (Aug 29, 2007)

Just be warned that there is bronze.. and other types of bronze - just like there is stainless... and other grades of stainless. They're both alloys and some alloys are better than others.

What I'm trying to say is that the quality of "bronze" can vary widely - far more widely than, say, '304 Stainless' or '316 Stainless' - so if you're buying "bronze" it's important to check with the foundry exactly what it is you're buying and whether or not it's ok for marine use.


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## JonEisberg (Dec 3, 2010)

killarney_sailor said:


> Thought I would start a new thread rather than burying this in the thread about losing a toggle at the head of the forestay since it might be general inters. The old toggle was bronze and the new one is stainless. In fact, you don't see many chromed bronze fittings anymore. Is this mainly a result of cost or are today's stainless fittings just better than bronze ones would be?


Coincidentally, I just replaced the same toggle you had fail a couple of months ago, when I took my forestay down to rebuild my furling unit, and replace the wire while I was at it...

All of my turnbuckle bodies and toggles are chrome-plated bronze... I lucked out finding a replacement this time, a new one from Wilcox-Crittenden on eBay at a very good price...


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## outbound (Dec 3, 2012)

If I had my way all metal fittings on my boat would be Monel or high quality bronze. Stays would be synthetic or bronze/Monel rod. One and done. Also would not have to go hunting around for replacements. The difficulty and cost of shipping I think would exceed to cost differential. However I have a stainless steel boat so buy Collinite by the gallon.


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## bob77903 (Nov 10, 2008)

Just had all my turnbuckles and toggles re-chromed. Decided I probably can't do better than the 40 year old bronze.


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## RichH (Jul 10, 2000)

outbound said:


> If I had my way all metal fittings on my boat would be Monel or high quality bronze. Stays would be synthetic or bronze/Monel rod. One and done. Also would not have to go hunting around for replacements. The difficulty and cost of shipping I think would exceed to cost differential. However I have a stainless steel boat so buy Collinite by the gallon.


Agree totally. The problem is that because of 'environmental reasons' bronze, monel, inconel, hastalloy, etc. manufacture of extreme consistent high quality is no longer or very rarely made in the USA. Bronze/monel/cu-ni/Ni-Al Bronze etc. manufacture is an exceptionally 'dirty' process and virtually all the foundries that once made exceptionally high quality for naval and aerospace, etc. use .... as well as the metallurgical knowledge/expertise no longer exist in the USA; the same for smelting of lead, zinc and other 'dirty' metals. Steel, ductile iron, etc. is rapidly following to be all asian produced.

I wouldnt 'rechrome' as fatigue is the ultimate destroyer of all dynamic structural metals.


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## aa3jy (Jul 23, 2006)

RichH said:


> Agree totally. The problem is that because of 'environmental reasons' bronze, monel, inconel, hastalloy, etc. manufacture of extreme consistent high quality is no longer or very rarely made in the USA. Bronze/monel/cu-ni/Ni-Al Bronze etc. manufacture is an exceptionally 'dirty' process and virtually all the foundries that once made exceptionally high quality for naval and aerospace, etc. use .... as well as the metallurgical knowledge no longer exist in the USA; the same for smelting of lead, zinc and other 'dirty' metals. Steel, ductile iron, etc. is rapidly following to be all asian produced.
> 
> I wouldnt 'rechrome' as fatigue is the ultimate destroyer of all dynamic structural metals.


Concur...The test these days for quality metals if it's good for the Chinese Military then the quality is good..other then that it's of questionable quality...


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## bob77903 (Nov 10, 2008)

RichH said:


> Agree totally. The problem is that because of 'environmental reasons' bronze, monel, inconel, hastalloy, etc. manufacture of extreme consistent high quality is no longer or very rarely made in the USA. Bronze/monel/cu-ni/Ni-Al Bronze etc. manufacture is an exceptionally 'dirty' process and virtually all the foundries that once made exceptionally high quality for naval and aerospace, etc. use .... as well as the metallurgical knowledge/expertise no longer exist in the USA; the same for smelting of lead, zinc and other 'dirty' metals. Steel, ductile iron, etc. is rapidly following to be all asian produced.
> 
> I wouldnt 'rechrome' as fatigue is the ultimate destroyer of all dynamic structural metals.


Your opinions stated above, are exactly why I did rechrome my better material, metallurgy, manufactured toggles, turnbuckles.


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## killarney_sailor (May 4, 2006)

I assume that the toggle that failed was because of fatigue as a result of long use and many miles. Certainly there was no shock loading involved. The new stainless one is certainly pretty but I am sure it will not stay that way for long. My wife has her PhD in metals and corrosion and we saw some titanium fittings in a store here. She thinks that is the material but the price is ridiculous.

i think that Rich may have it nailed that bronze production has just become too problematic from the environmental and cost perspective. When my boat was built it had a lot of bronze fittings, not so many anymore.


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## knuterikt (Aug 7, 2006)

Any pictures of the old toggle?
Is the forestay toggled so it can articulate inn both directions?


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## Bill-Rangatira (Dec 17, 2006)

there are so many types of bronze alloys and fot that matter stainless 
you would need a metalurgy degree to truly compare the two


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## killarney_sailor (May 4, 2006)

They took the old toggle, but it was very good New England technology from 30+ years ago. It was installed properly for the task - it just got old and gave up the ghost. Why wife has three degrees in metallurgy fields and she could not tell you what an alloy is without the ability of lots of test equipment. Unfortunately or not you need to trust the vendors. The new toggle is Navtec. Good rep I think, if this one lasts for 30 years it will outlast me.


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## bobmcgov (Jul 19, 2007)

killarney_sailor said:


> I assume that the toggle that failed was because of fatigue as a result of long use and many miles. Certainly there was no shock loading involved. The new stainless one is certainly pretty but I am sure it will not stay that way for long. My wife has her PhD in metals and corrosion and we saw some titanium fittings in a store here. She thinks that is the material but the price is ridiculous.
> 
> i think that Rich may have it nailed that bronze production has just become too problematic from the environmental and cost perspective. When my boat was built it had a lot of bronze fittings, not so many anymore.


Bronze (like any copper alloy) can 'fatigue' in the sense of work hardening/embrittlement, but good silicon bronze is fairly resistant to fatigue if kept w'in a working limit of, say, 25% breaking strength. I would guess (guess!) that you experienced enuf transient dynamic loads during your recent passages to push the fitting past its limits frequently enuf to cause work hardening. There is also the possibility of galvanic corrosion, tho that's an unlikely place for it.

Stainless also work hardens -- but that's mostly during machining, at the micron-thick cutting interface. In operation, your steel alloys are highly resistant to cold hardening. That's one of the glories of steel. They can also be hot-worked w/out totally messing up their properties, which cannot be said of bronze or aluminum.

Bronze hasn't got so expensive because of environmental concerns -- you can bet the Russians, Chinese, and Chileans aren't exaclty following the Clean Water Act -- but rather because the commodity price of the base metal (copper) tripled around 2004. This was during the peak of the US housing boom and more importantly China's & the UAE's city-building boom, which continues today, albeit slowing. As someone who was wiring a new house and shop at that time, I can tell you what it did to the cost of Romex. Also, bronze has become very much a specialty or niche product, with fewer smelters or founderies working it. The price is high because it is no longer a common industrial metal, except for certain military or chemical-handling operations where price is no object.

Titanium is an amazing metal with some issues when used for rigging hardware. For straight chainplates, there is perhaps no better material. Bolts and forged fittings, no problem. But there have been a number of documented failures of cold-worked parts, notably tangs and chainplates bent in vices and dies. The alloys seem to exhibit acute work-hardening and embrittlement at the bending angle. Most recent example I know of was a failed Ti mast tang on the cruising cat _Ceilydh_.

Ceilydh Set Sail: Some days are like this

Not sure I would trust a random cold-formed toggle made of Ti. It has to be done just right: speed of bend, not bending back, elevating temperature before bending, heat treating afterwards. Cold-working or cold-forging Ti increases its strength, but this benefit comes at the expense of ductility & possible fracture unless the metal is later annealed to relieve stress. It's a tricky metal that requires skilled & knowledgeable people working it. If you just have Charlie bending your tang or toggle in his bench vice w/ a pair of locking pliers, stainless is a much more forgiving material. It's possible Stumble (of Allied Ti) can set you up with a proper forged or milled or shaped titanium toggle.

http://www.alliedtitanium.com/vupdc_Results.php?S_UDescription=toggle&x=0&y=0


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## killarney_sailor (May 4, 2006)

I have a new stainless toggle that will last many more years than I need. Titanium fittings are outside my (financial) weight class. I am sure that my fitting just wore out. I have been trying to compare the loads from our trip to what a boat would get in normal usage … and I really can't make a proper comparison. In the Indian Ocean we had three weeks where the winds were never less than 25 knots and our daily averages were always above 6 knots. You get used to it and don't give it much of a second thought at the time, but in retrospect the number of cycles as waves pass every ten seconds or so is incredible.


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## bobmcgov (Jul 19, 2007)

The dynamic loads and load cycles of offshore sailing are so much different than years of coastal; and I'm not sure how accurately they can even be enumerated. "Multiply by five" seems to be the design approach. 

Just hunting around, I found quite a number of suppliers for bronze eye toggles, chromed and un-. Suncor and Unicorn Stainless both sell plain; Downwind Marine has some lovely chrome-plated bronze specimens for decent prices. Fisheries Supply sells the same toggles. Nice soft curves that reduce stress risers. Among the milled stainless type, I'm a huge fan of Hayn rigging gear. Their bronze body/stainless stud turnbuckles will be going on our Ballad.

Speaking of which ... crap metallurgy is not a new thing. This is a stainless/stainless turnbuckle from the upper shroud. Probably not original to the boat, since the factory wire was metric. But I'd bet at least twenty years old.





It's _possible_ those cracks are artifacts from the casting/forging process & not radiating from those nasty, acute-angle slots.... Don't care to bet the rig on it, tho. You can also see the severe galling of the stud threads. Somebody was slacking on the lanolin front. That's maybe the best argument for bronze-body turnbuckles: no galling, easy to adjust under load.


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