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Heat treating stainless

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I have Ronstan calibrated turnbuckles. The main problem with them is that the turnbuckle nuts are machined to be exactly round numbers. My understanding is that it's the wrench that should be the exact size and nuts are supposed to be about 0.5mm smaller - or thereabouts, depending on the size. The usual convention - nuts are smaller than the wrenches, which are the size that's printed on them - exactly. Anyway - I can't get an off the shelf wrench to fit the damn Ronstan turnbuckles.

Adjustable wrenches are a pain in the ass and they corrode and become crap within a couple of months. So I decided to make some custom wrenches using an online machine shop. For $100 I received two beautiful and accurately machined 1/4" thick 304 stainless wrenches with exactly the right sizes on each end for the shrouds. Awesome.

Until it blew like snot this weekend and I needed to crank on the rig - it opened up one of the wrenches and now it slips on the nut - useless. My plan is to squeeze it back to size in my vice, but I suspect that it will just stretch again. Is there a heat treatment for 304 stainless that will help lock the size down once I have pressed the wrench forks back together? 

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I'm pretty sure you can't harden 300 series steels, 400 series you can, most cheap chinese knives are 400 series for example, some decent ones for high corrosion areas are 400 series too(trading a bit of edge life for corrosion resistance).   If you find the wrench is bending, maybe look at a remake from a steel knifemakers would use, then send it out to one of the many heat treat places in the US(many knife makers send their knives to big heat treating facilities since they have computer controlled ovens.  )

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It will be work hardened by the process described.... but heat, no.  I would try again with maybe bronze, monel, titanium something like that or just a larger cross section for the SS wrench.  Interesting problem.  

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you want 420 or 17-4ph stainless, they both can heat treated and are used to make SS wrenches. Ronstan turnbuckles are  imperial threads and nuts . have you tried both metric and imperial wrenches?  some of the sizes of the wrenches are very close. there are manufactures that make SS wrenches, not cheap but sometimes worth it. Steritool is one that makes them. 

http://www.steritool.com/tools/open_end_wrench.htm

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^ This.

If metric doesn't fit then try Whitworth.

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You're focused on the symptom instead of the problem:

  1. Don't adjust your rig when it's highly loaded; remember this is illegal when racing, too
  2. Stop buying tools that corrode, get a quality non-corrosive crescent wrench like this or this.

 

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46 minutes ago, Moonduster said:

 

  1. Don't adjust your rig when it's highly loaded; remember this is illegal when racing, too

 

The Melges 24 fleet is doing this constantly. I asked for another 30 seconds before the tack too many times to count so I could finish winding up (or unwinding) that f'ing rig. Don't know of any other classes that allow this (there may very well be some). I also have no idea if the OP is racing in a fleet that allows such adjustments while racing. If not, then yes, adjust the unloaded shrouds on the leeward side. 

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I know of a Viper guy that used the turn buckles and had "knobs" machined out of G10 to fit the nuts so they could be loosened when not loaded up and the TB adjusted. 

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Maybe a stupid idea, but why not just get a slightly undersized open ender and die grind the jaws until it fits? You can also get those self locking style jobbies that don't have the rust (and seize) prone worm adjustment of a regular shifter. And 400 grade stainless is what you want if persisting with the DIY route, but there are two distinct types - ferritic and martensitic. Martensitic is the stuff they make knives and forks from and is the heat treatable stuff that you'd need.

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3 hours ago, toecutter said:

Maybe a stupid idea, but why not just get a slightly undersized open ender and die grind the jaws until it fits? You can also get those self locking style jobbies that don't have the rust (and seize) prone worm adjustment of a regular shifter. And 400 grade stainless is what you want if persisting with the DIY route, but there are two distinct types - ferritic and martensitic. Martensitic is the stuff they make knives and forks from and is the heat treatable stuff that you'd need.

A good idea that I would take one step further - Don't freehand it on grinder. Mount it in a milling machine and accurately machine out the faces of the wrench. Find the closest metric or imperial wrench that is too small and use that as the starting point. That way you are taking off less than 1 mm or less than 1/16 of an inch.

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Or this https://www.mcmaster.com/#crescent-wrenches/=1credj9

https://www.mcmaster.com/#crescent-wrenches/=1credj9

304 SS should be more than strong enough for adjusting turnbuckles on boats.  Not actually sure what grade these are They also have lots of Ampco metal options, but that is really to avoid sparks in explosive environments.  As another poster stated measure the nut and pick a metric or imperial that fits.

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I wou,d rather change a spanner than a turnbuckle personally.

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On 5/7/2018 at 6:24 AM, Moonduster said:

 

  1. Don't adjust your rig when it's highly loaded; remember this is illegal when racing, too.

 

Please find me the rule that says you can't adjust rig. Maybe IOR? But not in RRS. 

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2018 IRC 21.1.6 and most PHRF fleets prohibit adjustments of standing rigging while racing unless the boat is a member of a one-design class and the class allows standing rigging adjustments.

 

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Ok I could never find it before.  Locally our PHRF has no rules regarding adjustments and I can't find anything in the ORC rules either.  

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12 hours ago, Moonduster said:

2018 IRC 21.1.6 and most PHRF fleets prohibit adjustments of standing rigging while racing unless the boat is a member of a one-design class and the class allows standing rigging adjustments.

 

Adjusting while racing is allowed for races over 21 nautical miles in our fleet. However, I'm not talking about adjusting while racing - the wrench was damaged while setting up prior to racing - on the low, less-loaded, side - we were in breeze and I really needed more rig on.

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