Telescoping box section

[sarge]

Does anybody know what is the optimum clearance for box section and round, to fit inside each other?

Regards

 

[Welderpaul]

Depends what your wanting to do. Your going to be limited by standard outside diameters/dimensions and wall thicknesses. Some will give a sloppy fit, some tight. Theres also a seam inside some types of box and circular section to think about.

 

[rtbcomp]

Any good

http://www.rondexter.com/professional/rigging/telescoping_pipe_and_tube.htm

http://www.metals4u.co.uk/products.asp?cat_id=1517

 

[sarge]

What i need to know is if i put 60x4 inside 70x4 inside 80x4 inside 90x4 square tube will the fit be snug? Also 76.1x5 inside 88.9x5 round tube.
I know the clearance on the square is 2mm and the round 2.75.
Will it rotate easily and will the box section slide?

Regards Sarge

 

[Shox Dr]

There are "some" Square tubes that are drawn after welding, to remove the seam inside, but i cant for the life of me remember what it's called.

As for Round Tube, you need to be looking at CDS

 

[cutandshut]

Parker Steel black stocklist has a page for 'what fits inside what' for SHS, RHS & CHS.

 

[Wozzaaah]

Can you post a link for it? I've just had a look and can't find it on there.

 

[sarge]

Parker Steel black stocklist has a page for 'what fits inside what' for SHS, RHS & CHS.

Link please

 

[hotrodder]

http://www.parkersteel.co.uk/Literature, a tube fitting chart is listed in the index of (at least) the 'black steel stocklist'

 

[Wozzaaah]

Top man! Page 25.

 

[sarge]

still can't find it

 

[Wozzaaah]

Page 25 of this one.
Proper page 25, not Adobe's idea of page 25.

 

[Pete.]

I once saw a home-made device for removing the weld flashing from inside tubing to allow telescoping sections. It was a simple shuttle with some tool steel for a cutting edge as I recall.

 

[sarge]

All they are stating there is the ID of the tube which is pretty obvious.
What we need to know is what will slide inside each other, I would have thought that a 3MM clearance would be suffice, so 90,80,70,60MM box with a 3.5-3.6MM wall thickness would leave 2.8-3.0MM clearance.
The issue is, how much of the weld protrudes through on the inside of the pipe and would 3MM be enough?

Regards

 

[Pete.]

3mm will slap about like a willy in a welly. You want it much closer than that for sliding movement. It certainly won't fit any definition of 'snug'.

 

[sarge]

Next available option is 5mm which would be an interference fit to say the least?

 

[Shox Dr]

As I said in post#5 there are Square tubes designed to telescope. The rest will be hit and miss.

last time I bought Tube, was from these guys.

If they don't have any no one will