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I know i have seen a type of bolt but i don;t know what it's called or where to buy it..
A threaded bolt (probably cap head/ hex head) but the tip has a captive rotating plate.
Any ideas what they are called, or even where thay are used.
Please help....
Have you tried doing a Google Images search ? - might spot something that's close without having to get the name exactly right.
Do you mean a captive washer under the bolt head, or at the thread end of the bolt, like a levelling foot?
Have you tried doing a Google Images search ?
yep - not even close - yet..
at the thread end of the bolt.
it's not so much a foot - as the bolt still fits through it's standard hole. eg m8.
What would it's purpose be? The only thing I can think of that would be close to that is a set screw with rotating tip - normally a ball bearing or brass/plastic insert in the end.
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What are you trying to do with it?
Might help narrow it down like.
it's pushing against a plate - the bolt is to set the position of the plate.
The bolt is digging in to the plate (it's stainless) - i thought that one of those screws with the 'spinny tip' would help. but bugger me i don't know what they are!!
It sounds a little bit like a variation of this sort of thing which is an adjustable or levelling foot.
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You turn the bolt which freely turns in the plate.
Think what your looking for is a toggle clamp stud. Quick google shows one in images
Can't see.one in its raw form in the uk. But suggest a toggle clamp and strip out the stud and end
https://www.amazon.com/JW-Winco-Stainless-Assembly-Diameter/dp/B00G5754D0
Ball and socket levelling mount???
http://www.vibrasystems.com/product/leveling-mounts-feet/b-series-steel-ball-and-socket.html