vyv_cox
Well-Known Member
Yes, my mistake. The OD on industrial pipe is constant so that the same fittings and hangers will fit every schedule. Wall thickness increases reduce the bore.
Stainless Steel Pipe and Tube; is there a difference?
- Thread starter richardbrennan
- Start date
Yes, my mistake. The OD on industrial pipe is constant so that the same fittings and hangers will fit every schedule. Wall thickness increases reduce the bore.
rob2
Well-Known Member
Although S/S looks the part, a much cheaper option would be to use a length of aluminium scaffold pole (2m no problem) and fit a pretty wood cover...
Rob.
Rob.
macd
Well-Known Member
Thanks. I think that might come under the heading of "legal and more arcane". A more recent legal version, if I remember correctly, is that something like "admission free, weekends excepted" means that you must expect to pay a charge at weekends. In other words, 'weekends' are an exception to the general rule that admission is free. In modern usage, neither amounts to very much for most of us, but the expression as routinely used...usually to support an argument...is fallacious and illogical.
I'll let everyone get back to their hollow cylinders now.
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Daydream believer
Well-Known Member
2or 3 lengths of alluminium scaffold pole set inside a lenght of 100 mm plastic soil pipe would do the trick
Sometimes ss pipe comes in long enough lengths to cut in half & have 2 smaller pipes .
This would save cutting waste
Sometimes ss pipe comes in long enough lengths to cut in half & have 2 smaller pipes .
This would save cutting waste
2Tizwoz
Well-Known Member
The link to a table of schedule 40 pipe etc. was so that you could see the dimensions rather than the prices.
Unless your existing tube is bowed so badly that it's unusable, couldn't you add sufficient additional strength by putting another pipe inside what you've got? That way you would keep the appearance of the shiny stainless.
Unless your existing tube is bowed so badly that it's unusable, couldn't you add sufficient additional strength by putting another pipe inside what you've got? That way you would keep the appearance of the shiny stainless.
PCUK
Well-Known Member
Fill the tube/pipe with epoxy resin and chopped ends. Unlikely to bend again.
2Tizwoz
Well-Known Member
Or combine an additional tube with the GRP filling between the two tubes, as PCUK suggests.
Iliade
Well-Known Member
What was the failure mode(s) of the original and the current strut?
if it 'crumpled' longitudinally, you need thicker walls. If it buckled (Euler buckling) you may need a wider pipe or you may need to remove any bending moment from the pipe's ends.
E.g., If the floors have failed the keel will rotate, causing the compression strut to fail. If the end plates are not normal to the vertical axis of the strut, but the keel and deckhead are, then the strut could fail, and vice versa.
if it 'crumpled' longitudinally, you need thicker walls. If it buckled (Euler buckling) you may need a wider pipe or you may need to remove any bending moment from the pipe's ends.
E.g., If the floors have failed the keel will rotate, causing the compression strut to fail. If the end plates are not normal to the vertical axis of the strut, but the keel and deckhead are, then the strut could fail, and vice versa.
Birdseye
Well-Known Member
No. Its a convention in the steel industry. You will find that the dimensions differ too - one is sized on ID and the other on OD. For your purposes the biggest issue is likely to be surface finish. You will be very lucky to find polished pipe.
Size for size and in the same condition, the strength will be the same. However, if the tube is cold drawn it will be higher tensile
cpedw
Well-Known Member
But not quite correctly. Second person plural is amatis, not amanti.
http://www.urbandictionary.com/define.php?term=amo%2C%20amas%2C%20amat%2C%20amamus%2C%20amatis%2C%20amant
Amanti is dative & ablative masculine, feminine & neuter forms of amans, "loving". In my defence, can I mention that I had to look that last bit up?
Derek
30boat
N/A
I'm sorry but that's a terribe and expensive idea!
richardbrennan
Well-Known Member
The finish is not too important as the fabricators will polish it up, they can also re-use the end plates so this will help with the cost. I note the comment on whether it crumpled or bowed. It did bow, it's difficult to know how best to line it up, the top seems to be pretty much under the mast and we lined up the bottom by sighting other verticals such as door frames and bulkheads; I am told a spirit level or plumb line are pretty useless on a boat. I am currently looking at going up from 3 mm to 6 mm wall thickness; this is probably unnecessary as long as I am not dumb enough to over tension the rig, but I certainly don't want to go through this experience for a third time!
Daydream believer
Well-Known Member
So now you know why I failed latin GCE
It is the verb " to Love" as in "I love", "you love" etc
My how I hated that teacher - certainly no love lost there
But getting back to the thread- If the OP can straighten the old post a bit he could put it inside a larger diameter post if he cannot get a thick enough walled pipe so the new pipe holds the old one in line plus increases the compression resistence of the strut
& going off thread again - Will some bright git suggest the latin for "i support" "you support" " we support" etc etc:sleeping:
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earlybird
Well-Known Member
dgadee
Well-Known Member
I've heard of machine tools being built with epoxy and granite chippings. That would work. Might dig the bow in a bit, of course.
30boat
N/A
Concrete would work just as well for a fraction of the cost.Heavy though.
Scotty_Tradewind
Well-Known Member
I must admit I had to Google https://www.google.co.uk/search?......idgbgI&ved=0CCIQsAQ&biw=1003&bih=651&dpr=1.25 as I have always known it as a post.
I'm amazed you've bent two especially as they are taking the force in compression. I'd be interested to know what's going on in your boat to cause it.
Mine is a heavy gauge steel and boxed into a bulkhead and I can't imagine bending that.
S.
I'm amazed you've bent two especially as they are taking the force in compression. I'd be interested to know what's going on in your boat to cause it.
Mine is a heavy gauge steel and boxed into a bulkhead and I can't imagine bending that.
S.
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richardbrennan
Well-Known Member
The mast pillar was a known weakness on the early Westerly Ocean 33 and it was beefed up from about 6 cm in diameter to 9 cm diameter in the later boats. The first one bent when the shrouds were tightened to the specifications given by Selden for a particular tension gauge. I persuaded the rigger to go past were he was happy with the second post, believing I was now bullet proof, but probably put even more tension in the rig and managed to bend the second post as well. It's been an expensive lesson and one I will not be repeating. The fabricator tells me that the price for the pipe/tube in 9 cm diameter and 3 mm wall thickness he was quoted was about £34 per meter, which makes £300 for two meters seem rather a lot, but he can only order it in 6 meter lengths. However, even assuming that that did not include the dreaded VAT, it's still not £300. I'll look into Aalco and Nero Stainless; thank you for the suggestions.
I cannot help with the Latin!
I cannot help with the Latin!
Scotty_Tradewind
Well-Known Member
Sorry if this sounds rude... not intended...
why use stainless? Is it because it can be seen and has to shine?
What about a mild steel or something similar?
S.
why use stainless? Is it because it can be seen and has to shine?
What about a mild steel or something similar?
S.
richardbrennan
Well-Known Member
The support pillar is in the middle of the main cabin and comes up through the table. It's appearance is therefore important but I have seen them cased in so I suppose that is a possibility but obviously this would have a cost as well.