HELP ! keel

S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Hello to you all.
I am a new (to me) hunter 450 owner. uk based.
Following advise from this great site, i checked my keel nuts for torque.
Ohhh no. Several loose.
Removal has revealed damaged threads. Bolts appear healthy.
Can you please tell me what is the Thread size used.
Im thinking one inch Whitworth ?
All help and guidance greatfuly received.
kind regards,
Leslie.
 
Jake N Eggs

Jake N Eggs

.
Jun 2, 2011
347
Hunter H33 Port Credit Harbour, ON.
Whitworth? I haven't heard that in many years. I am originally from Inverness so I am familliar with Whitworth. The Whitworth threads, if I recall correctly, were 55 degrees. I am pretty sure that the threads will be UNC which is 60 degrees. If the bolt size is 1" then the thread will probably be 8 threads per inch. 1" - 8 UNC.

Welcome by the way, form Canada.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Jake N Eggs said:
Whitworth? I haven't heard that in many years. I am originally from Inverness so I am familliar with Whitworth. The Whitworth threads, if I recall correctly, were 55 degrees. I am pretty sure that the threads will be UNC which is 60 degrees. If the bolt size is 1" then the thread will probably be 8 threads per inch. 1" - 8 UNC.

Welcome by the way, form Canada.
Click to expand
Hi there,
i thank you kindly for your rapid response.
i will go for 1" - 8 UNC. 8 t.p.i. certainly looks right.
55 degrees`/ 60 degrees` i would not wish to get it wrong.
Thank you again.
kind regards,
Leslie.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Jake N Eggs said:
Whitworth? I haven't heard that in many years. I am originally from Inverness so I am familliar with Whitworth. The Whitworth threads, if I recall correctly, were 55 degrees. I am pretty sure that the threads will be UNC which is 60 degrees. If the bolt size is 1" then the thread will probably be 8 threads per inch. 1" - 8 UNC.

Welcome by the way, form Canada.
Click to expand
Hi there Jake,
I thank you for your earlier response.
I have received this information and thought that you may be interested.
.
"All keel bolts to be 1" dia. UNC 10 type 316 st. stl"
.
Do you know the designation of "10 type" ?
.
........
The official drawing for the 450 - 460 keel.
.
http://www.marlow-hunter.com/export... Hunter 1997-2005 X/450-460 Keel Drawing .pdf
.
Also, I made an error.... its a 1997 not 1987. whoops.
Thank you.
very kind regards,
Leslie.
 
Jake N Eggs

Jake N Eggs

.
Jun 2, 2011
347
Hunter H33 Port Credit Harbour, ON.
Hello Leslie,

I am not sure what the 10 stands for. It could indicate that it is a full size nut as opposed to a half size nut used as a locknut. Like on a prop lock nut. The drawing clearly states that it is UNC which is Unified National Coarse. The UNC thread pitch for 1" is 8 TPI. I don't believe there are different grade of nuts when 316 stainless is specified.

Hope this helps.
 
Jake N Eggs

Jake N Eggs

.
Jun 2, 2011
347
Hunter H33 Port Credit Harbour, ON.
The drawing is only specifying the keel bolt so my statement about the nut is incorrect. The statement about the grade is still valid for the bolt.

I think that you would be ok with standard 1" UNC 316 stainless nuts. If there is room you could install a second nut as a locknut.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Jake N Eggs said:
Hello Leslie,

I am not sure what the 10 stands for. It could indicate that it is a full size nut as opposed to a half size nut used as a locknut. Like on a prop lock nut. The drawing clearly states that it is UNC which is Unified National Coarse. The UNC thread pitch for 1" is 8 TPI. I don't believe there are different grade of nuts when 316 stainless is specified.

Hope this helps.
Click to expand
Hi there Jake,
That is good of you to respond so quickly again.
You were certainly right with, UNC.
I will go to our, "nut n bolt shop" with your guidance and i will feed back the results.
I am feeling confident again.
Thank you.
Kind regards,
Leslie.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Jake N Eggs said:
The drawing is only specifying the keel bolt so my statement about the nut is incorrect. The statement about the grade is still valid for the bolt.

I think that you would be ok with standard 1" UNC 316 stainless nuts. If there is room you could install a second nut as a locknut.
Click to expand
.
.
Hello again Jake,
" I think that you would be ok with standard 1" UNC 316 stainless nuts. If there is room you could install a second nut as a locknut."
.
yes indeed, good advise and i will do that.

very kind regards,
Leslie.
 
F

Fred Villiard

.
Dec 28, 2009
397
Macgregor M25 trailer
Be sure to use some anti-seize compound on the bolts, stainless bolts and nuts have a habit of galling and ruining the threads if you don't.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Hello Fred,
That is very helpful, I thank you.
"Galling"
is new to me and for the guidance of others i paste below.
The assistance i am receiving is great.
I thank you all very much.
very kind regards,
Leslie.
This problem is called "thread galling." According to the Industrial Fastener Institute's 6th Edition Standards Book (page B-28),

Thread galling seems to be the most prevalent with fasteners made of stainless steel, aluminum, titanium, and other alloys which self-generate an oxide surface film for corrosion protection. During fastener tightening, as pressure builds between the contacting and sliding thread surfaces, protective oxides are broken, possibly wiped off, and interface metal high points shear or lock together. This cumulative clogging-shearing-locking action causes increasing adhesion. In the extreme, galling leads to seizing - the actual freezing together of the threads. If tightening is continued, the fastener can be twisted off or its threads ripped out.
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
All better now

Jake N Eggs said:
The drawing is only specifying the keel bolt so my statement about the nut is incorrect. The statement about the grade is still valid for the bolt.

Dear Jake,
Thank you for helping me.
I can confirm that 1" UNC - 8 .... and 316 stainless was the answer.
plenty of lubrication.
I have been busy today.
All nuts replaced, torqued, Rested and re torqued.
Second Lock nuts fitted.
I am impressed with the wealth of knowledge that is available and so willingly offered.
Thank you.
very kind regards,
Leslie,
Click to expand
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Fred Villiard said:
Be sure to use some anti-seize compound on the bolts, stainless bolts and nuts have a habit of galling and ruining the threads if you don't.
Click to expand
Thank you for helping me.
I can confirm that 1" UNC - 8 .... and 316 stainless was the answer.
Plenty of degalling lubrication.
I have been busy today.
All nuts replaced, torqued, Rested and re torqued.
Second Lock nuts fitted.
I am impressed with the wealth of knowledge that is available and so willingly offered.
Thank you.
very kind regards,
Leslie,
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
A very big Thank you for helping me.
Thank you.
I can confirm that 1" UNC - 8 .... and 316 stainless was the answer.
Plenty of degalling lubrication.
I have been busy today.
All nuts replaced, torqued, Rested and re torqued.
Second Lock nuts fitted.
I am impressed with the wealth of knowledge that is available and so willingly offered.
Thank you.
very kind regards,
Leslie,
 
S

sunsetpassion

.
Jan 26, 2015
19
hunter 450 passage Dover
Fred Villiard said:
Be sure to use some anti-seize compound on the bolts, stainless bolts and nuts have a habit of galling and ruining the threads if you don't.
Click to expand
Dear Fred,
The Oil you suggested was essential.
A good lesson.
I hope that others benefit from your guidance.
Thank you.
Very kind regards,
Leslie.
 
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