1 1/2 BSP Spanner???

I don't think BSP has standard spanner sizes as such, but uses bolt hexagon sizes as appropriate.
You'll need to measure the AF size of your hexagon and match that. Assuming it's ~2 1/4 inches AF, that will cost plenty unless you find one second-hand or a pressed steel or chinese cheapo.
A biggish adjustable will be OK, but probably still pricey.
That's why stillsons or similar are popular
 
Measure it and have a look on ebay.
At these sizes, you can get away with a tolerance of a mm or so?
So look at AF and metric.
You can sometimes find box spanners.
I bought something to fit a really awkward plumbing back nut, the tool was sold for Land Rover hubs nuts or something.
 
lw395 said:
.... the tool was sold for Land Rover hubs nuts or something.
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Indeed ..... I've done plenty of these recently with two Land Rovers parked on my drive in various states of re-construction. The Land Rover ones are 2 1/16 inch imperial so close to 52mm AF. On old Landies they've usually been chiselled on and off but I bought the right box spanner online a few months ago for £5 as that seems a much better solution. :)

Richard
 
I bought a big Bahco adjustable when I was struggling with a seacock last year, one of those ones with the gauge on the jaws, opens to close to 2" (from memory) handle is not too long so it can be used in lockers and can be extended with a bit of pipe when I have more room. Versatile tool and reasonably well made with little visible play in the jaws.
 
LittleSister said:
Where the hell can I get a spanner to fit a 1 1/2" BSP fitting (e.g. thru hull, seacock, etc.)?

I've struggled to find any for sale, or even reference to the exact size of the jaws/nut.

Given these are common fittings, what's the big secret?
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If you are able to drill, cut and file a piece of 1/4 inch steel plate you could make your own crowsfoot spanner to use in conjunction with a 1/2 inch square drive socket set. I find this type is far easier in confined spaces where you can't swing a Stinson. Something like this http://www.ebay.co.uk/itm/NEW-Snap-...747155?hash=item360b6a4253:g:2JgAAOSwXeJYCJbw

Www.solocoastalsailing.co.uk
 
I had a similar issue with an ancient stuffingbox nut. Ended up getting an old spanner for a quid amongst a collection of old obsolete tools at a carboot and cut and ground it to size. Now a perfect fit.
 
Thanks for all the suggestions.

I did make a spanner many years ago, but I now have none of the tools, the workspace or the patience to do it again.

Box spanner won't do as in at least one instance I will need to attack from the side of a connected up assembly.

I'm liking the Swedish pipe wrench, but the handle's probably to long to use in the confined spaces involved. (I think when I did this job on another boat years ago I used a stillson, and it was quite a fight.)

I'd already seen the wide jaw adjustable wrench. That one won't open wide enough for 1 1/2" BSP, but I may get one anyway for other tasks and smaller fittings.

Sailorman's chain wrench suggestion is the one most appealing for now. I actually have one somewhere, and if i can find it (unused for years) I won't need to take him up on his kind offer of a loan.

What has puzzled me is how hard it has been to find a spanner large enough, or any info about the 'standard' BSP spanner size (despite plenty about thread angles, tapers and tpi).

If there is no standard spanner size that would explain the latter, though I'm sure I read a detailed spec table for BSP a while back with spanner sizes, but could neither remember the size (53mm? or 57mm? across flats), nor find that source again. I just checked a 1 1/2" BSP nut I happen to have at home, and found it to be about 59mm AF, but that is from a non-metal Tru-Design Marelon fitting so may well not be standard spanner size even if there is one.
 
LittleSister said:
If there is no standard spanner size that would explain the latter, though I'm sure I read a detailed spec table for BSP a while back with spanner sizes, but could neither remember the size (53mm? or 57mm? across flats), nor find that source again. I just checked a 1 1/2" BSP nut I happen to have at home, and found it to be about 59mm AF, but that is from a non-metal Tru-Design Marelon fitting so may well not be standard spanner size even if there is one.
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As per my earlier post, if there is a standard for 1 /1/2" BSP hexes, I've read that it's 57mm.

However I'm sure I've read somewhere that many supposedly "1 1/2 inch" fittings are actually more like 1 1/4 inch but with a larger bore, which the general meatiness at that size allows. This could explain the 53mm hex I mentioned earlier, which I've seen described as the 'standard' for 1 1/4.

Or I could be quite wrong. Your hex is what it is. Good luck.
 
You can often get an oversized open spanners to fit by using shims. I have found all-hard hacksaw blades usefull for this. Just snap them off as necessary.
 
A neat trick I've seen is to use a large toolmaker's clamp assembled with the nut between the threads. You can then apply leverage by various means including strap wrench. bolt-on handle, hammer etc.
 
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