Torquing Keel Bolts

[John Alexander Stewart]

I've been searching for keel bolt torque values, and practical experience, through the archives.

Lots of discussion about it, lets see: my Nonsuch 26C

The keel/hull joint is working slightly, antifouling paint distressed at stern in the joint, but disappears before the bow-end of the joint.  It was time, before launch, to have a peek at things.

Q1: What torque values should be used?

Q2: Would the nuts turn if I torqued them to the value I chose? 

I found lots of info, including:

----

C&C owners "Photo Album" site: (http://www.cncphotoalbum.com)

"do it yourself" tab on left, then to "Keel Bolt Torque Specifications"

3/4" diam bolt, 1-1/8 nut, torque 250 ft/lbs. C&C and Hinterhoeller had lots in common, as we all know, so this is a good site for us, too.

----

John Barbour back in 2019 joined a discussion, 

https://groups.google.com/g/ina-nonsuch-discussion-group/c/RBf6hXT3jPY/m/tlKT7B4ECwAJ

"For  3/4" and 1" mild steel bolts this would give 90 and 180 ft-lb torques"

----

The infamous 1994 Nonsuch Newsletter article mentions (if I remember correctly) 175 ft/lbs for the 3/4" studs.

----

Values all over the map. John Barbour, and others on the 2019 thread mentioned above, give interesting insights; worth reading.

I decided on 80 ft/lbs, I had no idea what the previous owners did, and thought "we'll see if they move" 

Move they did. Stern to bow, doing an initial torque of 70 ft/lbs, I was able to torque approximately 1/4 turn, descending to maybe 1/8 at the bow. going to 80 for the final pass, all moved very slightly. 

It was actually fairly easy to do. Torque bar, two 20" extensions, and deep socket. The longest bit was removing the mast lightning connector to the bow keel bolt. I'll check for 80 next time (the fall? next spring?) and see if they've moved. 

I should have checked the initial torque on that stern-most bolt; oh well. At least they are all "80 ft/lbs" tight now.

John Stewart

NS26C 046

Ottawa ON.

[Joe Valinoti]

As a retired mechanic, 80 seems kind of low to me.  My recollection of when I checked mine several years ago, it much higher.

 

Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

~~~~~(\_ ~(\_ ~(\_~~~~~~~~~~

--
You received this message because you are subscribed to the Google Groups "INA Nonsuch Discussion Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to INA-Nonsuch-Discussi...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/CAK8hy3%2BfwQxE-n_wsDDFCncpi%2Bjiwadnx3i%3Dhnfe1cs0PXmamw%40mail.gmail.com.

[John Alexander Stewart]

Joe - remember that these are 3/4" bolts, yours in your 30 are 1", so values should be approx 1/2.

I do agree that 80 might be low; hopefully someone else with 3/4" bolts will chime in.

What I did find "interesting" was that they were quite loose, if 80 is low, first torque at 70 told me that they were quite a bit less than that.

I'm all ears for others to chime in and comment.

John A. Stewart

NS26C 046

temporarily renamed:

"keel-not-a-wabblin''

Ottawa, ON.

[Tim in STL]

Here is a link to the Torque Table from the Blot Depot, for 3/4" SS they say 128 ftlbs.     https://www.boltdepot.com/fastener-information/bolts/US-Recommended-Torque.aspx

But the torque for bolting steel to steel is much higher than the  value for bolting to fiberglass.  I have no idea how much torque it would take to fracture the fiberglass and I don't want to find out by experimenting. 

Tim in STL

White O’morn NS26U #216

Harbor Point Yacht Club

West Alton, MO

 

[Herb Huber]

I was told that since the keel is solid fiberglass if the seal around the keel bolts is not letting water into the bilge a slight crack is just an aesthetic issue. But with my boat I was seeing light through the keel when it was lifted in & out of the water, so I decided to tighten them. A friend had the tools so when I asked a local boat repair shop how much torque we should apply he said "As much as you have strength for." 

Herb G. Huber, Lake Huron Nonsuch Association

MISTOFFELEES NS30C#91

Sarnia/Point Edward, Ontario

[Bob Illingworth]

The keel on a 30U is not solid fibreglass but solid lead.  It must be the case that the keel on a 30C is also lead.  See my slideshow on the Nonsuch.org website about keel removal and re-bedding at https://nonsuch.org/resources/Documents/Member%20projects/Keel%20Repair%20Illingworth.pdf

If this link doesn’t work find it the members’ area MEMBERS/MEMBERS’ TIPS & PROJECTS/KEEL REPAIR.

When the boatyard tightened up the bolts on the keel they did indeed ‘Used as much force as they had strength for’!

Bob Illingworth

Nonsuch Luck 30U #367 (GBR1262T)

Moored Brightlingsea, UK cruising the rivers of East Anglia and the North Sea.

--

You received this message because you are subscribed to the Google Groups "INA Nonsuch Discussion Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to INA-Nonsuch-Discussi...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/36269f45-478f-442a-83aa-14bdf632d6e9n%40googlegroups.com.

[Herb Huber]

Thank you Bob Illingworth for helping to clarify my bad writing. What I meant to write was "... the keel stump above the join is solid fiberglass...".  The top of my keel bolts did not have any rust and that was probably because there was no leakage around the bolts and it's a fresh water boat. Otherwise the shop would have dropped the keel and resealed the join and bolt holes. Thankfully it was just a DIY job.

Herb G. Huber, Lake Huron Nonsuch Association

MISTOFFELEES NS30C#91

Point Edward/Sarnia, Ontario 

[lase...@gmail.com]

Hi,

This was just posted on our clubs cruising forum...

It is for C&C's but of course applicable to many other boats as well

Willi Powell

NS324 109

Toronto

On Thursday, June 10, 2021 at 7:48:46 AM UTC-4 ivat...@gmail.com wrote:

[Mariner's Cat V 26C Brentwood Bay BC]

You torque bolts to stretch them to their designed load.  Every material will have a slightly different torque value for the same size.

https://www.engineersedge.com/material_science/torque_values_stainless_steel_13353.htm

[Elizabeth Powers]

This may not be relevant but I wonder if the torque values take into account that the bolts are imbedded in lead. Stainless to stainless torque is about the steel and it's characteristics. However is there a danger of moving the bolt in the lead, even a little if too much torque is used? 

Rob Powers

Respite 26C #50

Sidney BC

[Robert Illingworth]

If you see my slides how at https://nonsuch.org/resources/Documents/Member%20projects/Keel%20Repair%20Illingworth.pdf or if this link doesn't work in the members' area of the website in Members' Tips and Projects/Keel Repair you will see how the stainless studs are embedded in the keel during casting and therefore cannot move when the keel bolts are being tightened.

Bob Illingworth 

Nonsuch Luck NS30U

Brightlingsea, UK, cruising the rivers of Essex and Suffolk, and, the North Sea. 

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/1db2c2d3-5c73-4c4a-b357-a968d619b835n%40googlegroups.com.

[Ron Weber]

Just torqued the keel bolt nuts on my 22, and 100 ft lbs is all I could muster.

Ron Weber

N22 Magic Time

Punta Gorda Fl

[Joe Valinoti]

Did they turn at all, Ron??

 

Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

~~~~~(\_ ~(\_ ~(\_~~~~~~~~~~

 

From: Ron Weber

Sent: Thursday, November 11, 2021 7:23 PM

To: INA Nonsuch Discussion Group

Subject: Re: Torquing Keel Bolts

 

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/7fc68cd7-8124-41ae-91a2-067b57a3bd99n%40googlegroups.com.

[Ron Weber]

Joe,

I failed to check the torque first, however I did use PC Blaster and loosen the nuts first to make sure they torqued smoothly. From the force required to loosen them compared to the force to get them to 100 ft. lbs. I would guess that they were at about 70 - 80 ft. lbs. The reason for my concern was that when hauled and the weight of the boat was placed on the keel, water would weep from the joint. At first I was pretty distressed thinking that I was facing keel re-bedding. After reading the input on that topic here and other sources and speaking to someone who has seen many boats and many with the same issue, I felt reassured that re-torqueing would be suitable. I had no water intrusion but I was concerned about the bolts corroding, but I guess if I wasn't getting any water in the bilge then it wasn't getting to the bolts. This was the first time since I've had the boat that she has been hauled - only went in for the first time (since I acquired her) in March of this year. She is back in the water now and the bilge is dry. I have spent a great deal of time and a sizable amount of money bringing her back to top notch condition, but I am pleased with the result and love the boat.

Ron Weber

N22 Magic Time

Punta Gorda Fl

[Ernie Abugov N22 - #56 "Moustaches" Toronto]

Honestly, how can one NOT love their NS 22 ?

Ernie A. in Toronto

[Bob Neches (Me Gusta, Nonsuch 26U #233)]

Restarting this old discussion for two reasons:

1. To share some information in case of interest.  In looking for information on this topic, I stumbled over a March 1994 INA Newsletter page on the Nonsuch.org website under MAINTENANCE -- OTHER MAINTENANCE DOCUMENTS, which says that the keel bolts should be torqued to 350 ft. lbs. for 1" keelbolts and 175 ft. lbs. for 3/4" keelbolts.
    
   
2. I started looking into this to help a fellow owner, because we both think that we saw somewhere that it was not abnormal on a Nonsuch to see a small gap between the lead keel and the fiberglass hull, as long as the keel bolts were sufficiently torqued and there were no signs of leakage in the bilge.  Since this is different from the advice on other boats, I want to verify this as true or false.  Anyone out there who's aware of an authoritative document that bears on this?

Thanks,

-- Bob

   Me Gusta

   Nonsuch 26U #233

[JohnS]

Bob;

It is a good discussion. 

Here are my notes in my log book. I added a little bit, like "boat on the hard".

I'm not a weakling (I think!), and have good upper body strength. To torque, I sit on a 

seat somehow, hold the ratchet end of torque wrench with one hand, the end of the 

wrench in the other, and pull the end of the wrench. I could do 100 ft/lbs, but doubt I

could do 250. Maybe 150, maybe not.

Because of the extensions down to the keel bolts in the bilge, one

needs to keep the ratchet bit kind of centred over the keel bolt in question, and also

have the leverage to apply torque.

My goal is to have a repeatable reading year after year; I want no movement of the

materiel, no compression, no "oozing" of sealant, no cracking of the anti-foul paint

at the join when the boat is lifted.

It was better this year than the last; will see how last October's torque session affects

her this coming autumn after a summer of sailing.

----------------------

October 28 2021

(when Cat's Whiskers was on the hard)

I took the torque up to 100ft/lbs. Nonsuch 26C, 3/4" bolts, all 5 of them.

First round, all up to 90 ft/lbs, then to 100 ft/lbs.

The 2 nearest the stern moved a tiny bit.

June 8 2021

(boat on the hard again)

- keel bolts nut A/F 1-1/8"

- From the "C&C Owners Photo Album" web page:

    - 3/4" diam bolt - torque 250 ft/lbs.

John Barbour INA discussion list Mar 09 2019, suggests 90 ft/lbs.

I first torqued the 5 (from the stern to bow) firstly to 70 ft/lbs. 

Nuts closest to stern moved, closer to bow, no movement.

Then I torqued to 80 ft/lbs, and all tightened up slightly.

----------------------

You can see my notes and questions prior to this update in the email "replies" attached in this thread.

John NS26C 046 hoping for launch early June, Bath Ontario.

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/89b7bcd0-8cae-4c48-8d86-610539c343ebn%40googlegroups.com.

[Joe Valinoti]

Bob:  I think that the info you have in paragraph 2. is correct. 

 

Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

~~~~~(\_ ~(\_ ~(\_~~~~~~~~~~

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/89b7bcd0-8cae-4c48-8d86-610539c343ebn%40googlegroups.com.