Identifying nut needed, can only see bolt thread
 

On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Justin.

Identifying nut needed, can only see bolt thread
 

On May 24, 5:39*pm, Justin C wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

* *Justin.


The usual method is to buy a thread guage. It has little flat tabs
with various threads cut into it/ You offer them up to the bolt to
identify the pitch of the thread.

http://www.toolfastdirect.co.uk/acat...h_Guages_.html

Identifying nut needed, can only see bolt thread
 

On 24/05/2012 18:23, harry wrote:
On May 24, 5:39 pm, Justin wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Justin.


The usual method is to buy a thread guage. It has little flat tabs
with various threads cut into it/ You offer them up to the bolt to
identify the pitch of the thread.

http://www.toolfastdirect.co.uk/acat...h_Guages_.html

Yep, just what I was going to say.

Other than that, you could try some similar size nuts to see which one
fits, but the the thread gauge is the best way.

Identifying nut needed, can only see bolt thread
 

On Thursday, May 24, 2012 5:39:12 PM UTC+1, Justin C wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Justin.

If you've measured the diameter and the thread pitch or number of threads per inch then something like
http://www.efunda.com/DesignStandards/screws/screwm_coarse.cfm
(they also have pages with imperial threads on)
may help you find a likely candidate (remembering that the diameter as measured will almost certainly be smaller than the nominal diameter)
Mike

Identifying nut needed, can only see bolt thread
 

harry wrote:


http://www.toolfastdirect.co.uk/acat...h_Guages_.html
Guages?

Bill

Identifying nut needed, can only see bolt thread
 

"Justin C" wrote in message
...
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

take a nut off another anode, check it fits the one with the missing nut,
then take the nut to a nut and bolt shop to get more of the same.

Identifying nut needed, can only see bolt thread
 

"Justin C" wrote in message
...
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

take a nut off another anode, check it fits the one with the missing nut,
then take the nut to a nut and bolt shop to get more of the same.



I second that idea.

Mike

Identifying nut needed, can only see bolt thread
 

On 2012-05-24, harry wrote:
On May 24, 5:39Â*pm, Justin C wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Â* Â*Justin.


The usual method is to buy a thread guage. It has little flat tabs
with various threads cut into it/ You offer them up to the bolt to
identify the pitch of the thread.

http://www.toolfastdirect.co.uk/acat...h_Guages_.html

I've never heard of such a thing, what a marvellous idea.
Thank you for the suggestion.

The boat was built in the UK, around 1980, is it likely
that a commercial builder of the time would still be using
Whitworth, and not metric? I'm just trying to narrow the
gauges I should buy.

Justin.

Identifying nut needed, can only see bolt thread
 

On 2012-05-25, Gazz wrote:

"Justin C" wrote in message
...
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

take a nut off another anode, check it fits the one with the missing nut,
then take the nut to a nut and bolt shop to get more of the same.

There is an anode on the opposite side, the fittings were
the same, that might be an option. Thank you for the
suggestion.

Justin.

Identifying nut needed, can only see bolt thread
 

"Justin C" wrote in message
...
On 2012-05-24, harry wrote:
On May 24, 5:39 pm, Justin C wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Justin.


The usual method is to buy a thread guage. It has little flat tabs
with various threads cut into it/ You offer them up to the bolt to
identify the pitch of the thread.

http://www.toolfastdirect.co.uk/acat...h_Guages_.html

I've never heard of such a thing, what a marvellous idea.
Thank you for the suggestion.

The boat was built in the UK, around 1980, is it likely
that a commercial builder of the time would still be using
Whitworth, and not metric? I'm just trying to narrow the
gauges I should buy.

Plenty on the bay, dirt cheap.

Identifying nut needed, can only see bolt thread
 

On 2012-05-27, scorched was bm wrote:

"Justin C" wrote in message
...
On 2012-05-24, harry wrote:
On May 24, 5:39 pm, Justin C wrote:
On my boat there are zinc anodes held on by embedded bolts,
one has lost it's nut. How can I identify the nut needed
from only the thread?

I can measure the diameter, and can measure the number of
turns over a set distance. Is there a site I can look up
stuff like this?

Removing the embedded bolt and bedding a new one is well
beyond a job I'm happy to tackle.

Of course, this may all be moot, I may find, when the
boat's lifted, that the bolt has been eaten away because
there was no anode on it (I hope others in the area have
compensated).

Thank you for any advice you can give.

Justin.


The usual method is to buy a thread guage. It has little flat tabs
with various threads cut into it/ You offer them up to the bolt to
identify the pitch of the thread.

http://www.toolfastdirect.co.uk/acat...h_Guages_.html

I've never heard of such a thing, what a marvellous idea.
Thank you for the suggestion.

The boat was built in the UK, around 1980, is it likely
that a commercial builder of the time would still be using
Whitworth, and not metric? I'm just trying to narrow the
gauges I should buy.

Plenty on the bay, dirt cheap.

But are they also nasty - as in: inaccurate? I'd rather try
a reputable source for a quality product.

Justin.

Identifying nut needed, can only see bolt thread
 

On Sun, 27 May 2012 09:45:16 +0100, Justin C
wrote:


I've never heard of such a thing, what a marvellous idea.

What an interesting post. I had to identify an unknown thread last
week and hadn't heard of these either. In my case, I measured the
width of the bolt and tried to match it against tables I found from
googling "screw thread". I think I may have used results from
wikipedia because it was a web site I had heard of, unlike the other
search results.

The gauge seems to add a layer of complexity because you have to
measure the thread pitch and then look at a table to translate that to
diameter though. What's wrong with my method of measuring just the
diameter with a vernier calliper or micrometer? I suppose one flaw
might be that just measuring the diameter would not tell you whether
it was a 55 degree or 60 degree thread. Are there other flaws?

It seemed to work at the time to identify a 3/16" unc for me but I
might buy a gauge for next time. Thanks.