Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 03-12-2012, 10:41   #31
Registered User

Join Date: Nov 2011
Location: Fethiye Turkey
Boat: Lagoon 440
Posts: 3,164
Re: Stainless Bolts

You want to put a lubricant on your nuts (sorry about that) if they are the same grade ie 316# with 316# to prevent galling.

I've always used a magnet to differentiate between 304# and 316# it works.

Try to go for bolts so the shaft is inside the squeeze area (not thread) with the thread doing it's job. All too often common practise now seems to be what in Australia we call using 'Screws' ie threads all the way to the head.

Cheers interesting points in this thread regarding bronze strengths as a steel boat builder i was unaware of the strengths...
__________________

__________________
"Political correctness is a creeping sickness that knows no boundaries"
Lagoon4us is offline   Reply With Quote
Old 03-12-2012, 10:49   #32
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,340
Re: Stainless Bolts

Quote:
Originally Posted by Lagoon4us View Post
You want to put a lubricant on your nuts (sorry about that) if they are the same grade ie 316# with 316# to prevent galling.

I've always used a magnet to differentiate between 304# and 316# it works.

Try to go for bolts so the shaft is inside the squeeze area (not thread) with the thread doing it's job. All too often common practise now seems to be what in Australia we call using 'Screws' ie threads all the way to the head.

Cheers interesting points in this thread regarding bronze strengths as a steel boat builder i was unaware of the strengths...
Yes, great point, dont use universally threaded bots that are threaded right up to the head for sure and avoid any threads in the enclosed area as much as possible.
__________________

__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is online now   Reply With Quote
Old 03-12-2012, 10:56   #33
Registered User

Join Date: Nov 2011
Location: Fethiye Turkey
Boat: Lagoon 440
Posts: 3,164
Re: Stainless Bolts

It's sad how commonsense is no longer, we have gone through the bolted sections of our boat replacing the threaded "SCREWS". The idiots have used them to bolt up the walkways (as an example) with the thread cutting into the glass with every twist/movement of the boat...... aaaaggghhhHHHHHH!!!!
Cheers
__________________
"Political correctness is a creeping sickness that knows no boundaries"
Lagoon4us is offline   Reply With Quote
Old 03-12-2012, 11:01   #34
Marine Service Provider

Join Date: May 2012
Location: New Orleans
Boat: We have a problem... A serious addiction issue.
Posts: 3,940
Re: Stainless Bolts

Just as a FYI.

Magnetic testing of stainless DOES NOT DETERMINE GRADE.

While the conventional wisdom is that 304 is magnetic, while 316 isn't, this is just wrong. All a magnet can tell you for sure is that the material is either non-cold worked of either grade, or if it was cold worked that it has been thru a stress relief process.

This may be enough of a test for many things, but it is not really all that definitive. The only way to know what you have is a molybendium testing kit which start at around $250.
__________________
Greg

- If animals weren't meant to be eaten then they wouldn't be made of food.
Stumble is offline   Reply With Quote
Old 03-12-2012, 11:06   #35
Registered User

Join Date: Apr 2011
Posts: 2,243
Re: Stainless Bolts

For a reputable supplier, I've never had problems with McMaster Carr. The stuff they sell is what they say it is!
__________________
MarkSF is offline   Reply With Quote
Old 03-12-2012, 11:07   #36
Registered User

Join Date: Nov 2011
Location: Fethiye Turkey
Boat: Lagoon 440
Posts: 3,164
Re: Stainless Bolts

I've yet to find magnetic 316#

Well aware of test kits have owned a few BUT a quick magnet test will at least tell you if it's less than 316#...

304# has a low attraction whilst 316# has nil....
__________________
"Political correctness is a creeping sickness that knows no boundaries"
Lagoon4us is offline   Reply With Quote
Old 03-12-2012, 11:56   #37
Senior Cruiser
 
Jim Cate's Avatar

Cruisers Forum Supporter

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 11,440
Re: Stainless Bolts

Stumble is correct. No 300 series stainless is inherently magnetic, but may become so with cold working (as in heading or rolling threads). 304 is more susceptible to this than 316, and this is likely the reason that the magnet test seems to work in differentiating them. However, it means that 304 that has not been cold worked, or that has been annealed post cold-working could appear to be 316 if thus tested.

Cheers,

Jim
__________________
Jim and Ann s/v Insatiable II , lying Port Cygnet, Tasmania once again
Jim Cate is offline   Reply With Quote
Old 03-12-2012, 12:01   #38
Registered User

Join Date: Nov 2011
Location: Fethiye Turkey
Boat: Lagoon 440
Posts: 3,164
Re: Stainless Bolts

Get two washers out of your kit one 316# and one 304# and drag a magnet over them you will find the 304# will slightly attract.
__________________
"Political correctness is a creeping sickness that knows no boundaries"
Lagoon4us is offline   Reply With Quote
Old 03-12-2012, 14:38   #39
Senior Cruiser
 
delmarrey's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Now in Blaine, WA
Boat: Modified Choate 40
Posts: 10,702
Images: 122
Re: Stainless Bolts

Quote:
Originally Posted by Jim Cate View Post
Stumble is correct. No 300 series stainless is inherently magnetic, but may become so with cold working (as in heading or rolling threads). 304 is more susceptible to this than 316, and this is likely the reason that the magnet test seems to work in differentiating them. However, it means that 304 that has not been cold worked, or that has been annealed post cold-working could appear to be 316 if thus tested.

Cheers,

Jim
There is a lil'bit of difference between the two with the N & Cr content. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.

Mechanical Properties of Stainless Steel

http://www.euro-inox.org/pdf/map/Tab...perties_EN.pdf
__________________
Faithful are the Wounds of a Friend, but the Kisses of the Enemy are Deceitful! ........
A nation of sheep breeds a government of wolves!

Unprepared boaters, end up as floatsum!.......
delmarrey is offline   Reply With Quote
Old 03-12-2012, 14:46   #40
Registered User

Join Date: Dec 2007
Location: Duluth,Minnesota
Boat: Lindenberg 26 & Aloha 8.2
Posts: 984
Re: Stainless Bolts

Nice to see others concerned about threads within the hole ,i thought i was the only one who cared about this anymore, i size my bolts by the length of unthreaded shank i need and then add for nut and washers. Bronze nuts with ss bolts prevents galling which is why most quality open body turnbuckles use ss male threaded studs with chrome plated bronze barrels, unfortunatly i dont think you can buy bronze nylocs.

Steve.
__________________
clockwork orange is offline   Reply With Quote
Old 03-12-2012, 15:04   #41
Marine Service Provider

Join Date: Jan 2011
Location: Eldean Shipyard, Holland, MI
Boat: 1977 Pearson 30
Posts: 113
Re: Stainless Bolts

Quote:
Originally Posted by Lagoon4us View Post
Get two washers out of your kit one 316# and one 304# and drag a magnet over them you will find the 304# will slightly attract.
According to The Stainless Steel Information Center 300 series is not magnetic.

SSINA: Stainless Steel: FAQs
__________________
Anonymous7500 is offline   Reply With Quote
Old 03-12-2012, 15:25   #42
Marine Service Provider

Join Date: May 2012
Location: New Orleans
Boat: We have a problem... A serious addiction issue.
Posts: 3,940
Re: Stainless Bolts

While it is true that 304 is more prone to becoming magnetic when you see it in billet form you can stick a magnet on it, and it just falls off. The best that can be said if its non-magnetic is that it might be any series 300 stainless that has either 1) not been cold worked, or 2) been thru a stress relief process.

Since most fasteners are cold worked, and then not stress relieved you are generally safe, but I have seen 316 that was magnetized, and 394 that wasn't.
__________________
Greg

- If animals weren't meant to be eaten then they wouldn't be made of food.
Stumble is offline   Reply With Quote
Old 03-12-2012, 15:44   #43
Registered User

Join Date: Nov 2010
Location: London, UK
Boat: Helleman, 45' Steel Trawler
Posts: 92
Re: Stainless Bolts

have you considered using galvanized steel and then painting over?

everything on my old (50 years) wooden boat is galvanized, and i have been told that it lasts longer than stainless, and is stronger.
__________________
Honey Ryder is offline   Reply With Quote
Old 03-12-2012, 16:03   #44
Nearly an old salt
 
goboatingnow's Avatar

Cruisers Forum Supporter

Join Date: Jun 2009
Posts: 13,649
Images: 3
Quote:
Originally Posted by Honey Ryder
have you considered using galvanized steel and then painting over?

everything on my old (50 years) wooden boat is galvanized, and i have been told that it lasts longer than stainless, and is stronger.
I was just about to say that on a wooden boat galvanised is better, easier to see deterioration and less sudden failures.

Dave
__________________
Check out my new blog on smart boat technology, networking and gadgets for the connected sailor! - http://smartboats.tumblr.com
goboatingnow is offline   Reply With Quote
Old 03-12-2012, 16:10   #45
Marine Service Provider
 
boatpoker's Avatar

Join Date: Nov 2008
Location: Toronto, Ontario or Bahamas
Boat: Benford 38 Fantail Cruiser
Posts: 2,592
Re: Stainless Bolts

"galvanized steel" .. which of the several hundred available grades are you referring to ?
__________________

__________________
That hysterical laughter you hear as you sail a way in your "new" boat ..... is the seller.
boatpoker is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stainless vs Titanium Chainplates Stumble Commercial Posts 42 18-10-2016 16:17
Can I trust my new chainplates?? OrangeCrush Monohull Sailboats 27 12-04-2012 19:03
Keel Bolts casual Construction, Maintenance & Refit 2 06-10-2011 03:11
What Bolts to Use (Metal Interaction) ? Dulcesuenos Construction, Maintenance & Refit 15 15-07-2011 20:43



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 11:06.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.