tube for through-bolt holes

[Luke]

I'm starting to build up a list of stock to order in, and i need some tube to use as anti-crush tube when bolting through box section etc.

I intend to stock up with enough to keep me going for a while, but i don't want to get it wrong!!

My thoughts so far:

M10 - 15.9x2.5 - ID = 10.9
M12 - 19.05x3.0 - ID = 13.05
M14 - 22.2x3.0 - ID = 16.2
M16 - 25.4x4.0 - ID = 17.4

Any thoughts, opinions, guidelines etc?

cheers

Luke

 

[Welderpaul]

Whats this for?

If it's going to be galved - add an allowance for the loss of ID in the tube, - the galv tends to be a bit thicker in things like that cos it doesnt drain that freely.

 

[Luke]

not going to be galved.

Primarily, it's for a new rear crossmember for my defender 90. 6"x3"x4.9mm (yes, i know!) box.

It will be for general project use, it'll take a while to get through full lengths of each!

 

[rtbcomp]

Once in place apply plenty of grease, water will get in and rust the bolts solid in the tubes.

 

[Luke]

aye, been there, done that. it's fun getting bolts out of 15 yr old holes....

 

[Hitch]

Dont forget youll have a small seam in there aswell. The norm is to allow about 2mm clearence on bolt holes, not always that easy with sleeves.
Id go for the 25.4 in 3mm/3.2mm wall if you can get it, that would give you a bit more clearence.

 

[Luke]

25.4 x 3 is on the list.

 

[Hitch]

I see your list is seamless tube, that makes it nicer.
Id still go for the 3mm wall on the bigger stuff though.

 

[Luke]

yes, seamless is nicer, i'm just wondering how much more expensive it's going to be....

 

[drjim]

I needed some spacer for the roll cage bolts in my track car - chopped some bits of conduit up. Do you need the spacers to be a precise fit or just stop things squishing together - if so find some old conduit!

Jim

 

[Luke]

For this first job, they do just need to stop things squishing together, but i'd rather buy useful sizes that will be useful for other things

I need to go on a 'finding' trip, i fancy building a press and i reckon the local engineering works might have some rsj or similar that'll do the trick