any one a wizard at bolts ?

I hope you're not having the problem I just had. I tried for many, many hours, to refit the lengthy blade adjustment screw in my Stanley wood plane, without success. Until I mentioned it in the pub, and someone suggested it might be a left-handed thread. And it is!
 
simonfraser said:
i have:

diameter 9.32 thread 24G
diameter 9.85 thread 1.5

neither of the above fit in the holes to fix my hydraulic pump, nearly but not quite :(
...
Click to expand...
Thise thread pitches are very different, which of them looks the closer fit, can you say ?

Boo2
 
simonfraser said:
9.85 1.5 is the better fit, it engages by hand but then jams
Click to expand...

That sounds like a standard 10mm thread, with a 1.5mm pitch. Overall diameters of metric bolt threads are always slightly under the nominal size due to crest rounding. It would help to know where the equipment was made as that will allow a better guess as to whether the threads are metric or imperial. Metric threads have standard pitches for each diameter, but non standard finer pitches are also available, so if its metric 10mm x 1.25mm pitch or even 1mm pitch are also possibilities
 
simonfraser said:
9.85 1.5 is the better fit, it engages by hand but then jams
Click to expand...

As previously said sounds like a 10mm dia x 1.5 pitch. As well as measuring undersize due to thread peak rounding in manufacture, they are also cut slightly undersize to give clearance.

If it jams when doing up hand tight, does it jam immediately or gradually?
Could also be a fault in the hole which may need a tap running down
 
simonfraser said:
9.85 1.5 is the better fit, it engages by hand but then jams
Click to expand...

I am often confused by the wide variety of mechanical dimensions, so I've tried to combat such situations with a spreadsheet of all possibilities to,hopefully, find the nearest options. In your case this would give me these possibilities - the desig is followed by ‘threads per inch – tpi’ and (for most, distance between threads):-

3/8 desigs;
BSW: 16 (1.59mm)
BSF: 20 (1.27mm)
BSPT: 28tpi
UNC: 16 (1.59mm)
UNF: 24tpi
UNEF: 32 (0.8mm)
BSB: 26 (0.98mm)

3/16 JIC: 24tpi

1/8 BSP: 28tpi

M10: 17 (1.5mm)

If M10 is the “better fit” to date the closest of the above options would be BSW or UNC

Cheers
Bob
PS Corrections to the above gratefully received!
 
RIBW said:
I am often confused by the wide variety of mechanical dimensions, so I've tried to combat such situations with a spreadsheet of all possibilities...

3/8 desigs;
BSW: 16 (1.59mm)
BSF: 20 (1.27mm)
BSPT: 28tpi
UNC: 16 (1.59mm)
UNF: 24tpi
If M10 is the “better fit” to date the closest of the above options would be BSW or UNC

Cheers
Bob
PS Corrections to the above gratefully received!
Click to expand...

Nice work Bob. If 1.5mm pitch doesn't work, my money's on 3/8" UNC
 
Would be useful if the OP revealed the boat make and where she was built. Better yet, the pump make and origin. Would also be useful to know what the bolt is doing, a lot of hydraulic fittings use tapered threads.
 
PaulRainbow said:
Would be useful if the OP revealed the boat make and where she was built. Better yet, the pump make and origin. Would also be useful to know what the bolt is doing, a lot of hydraulic fittings use tapered threads.
Click to expand...

I assumed from the original post that it is a bolt hole and not a pipe fitting. So now bring into the equation 1/8 BSP or NPT
 
RIBW said:
I am often confused by the wide variety of mechanical dimensions, so I've tried to combat such situations with a spreadsheet of all possibilities to,hopefully, find the nearest options. In your case this would give me these possibilities - the desig is followed by ‘threads per inch – tpi’ and (for most, distance between threads):-

3/8 desigs;
BSW: 16 (1.59mm)
BSF: 20 (1.27mm)
BSPT: 28tpi
UNC: 16 (1.59mm)
UNF: 24tpi
UNEF: 32 (0.8mm)
BSB: 26 (0.98mm)

3/16 JIC: 24tpi

1/8 BSP: 28tpi

M10: 17 (1.5mm)

If M10 is the “better fit” to date the closest of the above options would be BSW or UNC

Cheers
Bob
PS Corrections to the above gratefully received!
Click to expand...

You might add Metric- fine threads.
In the case of this thread M10(F) might be a possibility ......... ( 1.25 mm pitch )
 
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Information on Screw Threads
Historical Background
It is considered by some that the screw thread was invented in about 400BC by Archytas of Tarentum (428 BC - 350 BC). Archytas is sometimes called the founder of mechanics and was a contemporary of Plato. One of the first applications of the screw principle was in presses for the extraction of oils from olives and juice from grapes. The oil presses in Pomeii were worked by the screw principle.

http://www.boltscience.com/pages/screw2.htm
 
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