Help sourcing steel tube please

[Wobbly]

Hi guys. I'm having problems trying to source round steel tube outside diameter of 25mm/1inch with an internal diameter suitable for an m12 bolt to pass through. I need enough for 8 x 44mm sections, to be used as bushings on wishbones on a buggy I am building. I just can't find any tube with a wall thickness that deep. Thanks in advance for any help

 

[langy]

If you know someone with a lathe it would be easy to turn up from bar, i'm pretty sure its not a standard size.

 

[JayRS4]

Think it`s going to be a case of getting some inch bar and access to a lathe, I can`t even imagine there`s a high pressure application that`d need a wall thickness like that.

 

[Paul.]

Hi guys. I'm having problems trying to source round steel tube outside diameter of 25mm/1inch with an internal diameter suitable for an m12 bolt to pass through. I need enough for 8 x 44mm sections, to be used as bushings on wishbones on a buggy I am building. I just can't find any tube with a wall thickness that deep. Thanks in advance for any help

They would need to be machined from solid bar, find a local machine shop but tell them that you want to weld them, a lot of machine shops use free cutting steels such as EN1A which contains sulphur or lead, and is not good for welding, especially something such as a suspension component, ask for EN3B or even better EN8

 

[Wobbly]

Thanks for the good advice guys. I was guessing I might have to go down the route of getting something machined, but I was hoping there might be something out there I could use off the shelf.

 

[pedrobedro]

Are you using the metal tube wall as the bushing against the bolt ? It's normally done with a crush tube with the bolt through it and flexible bushing inside another tube, using the bolt as a pivot is not the best idea.

 

[Wobbly]

Are you using the metal tube wall as the bushing against the bolt ? It's normally done with a crush tube with the bolt through it and flexible bushing inside another tube, using the bolt as a pivot is not the best idea.

That is what I was going to do. The buggy plans are a bit vague in relation to the pivot point of the wishbone. I have sourced pre made brackets which are for a Locost kit car, they are pre drilled for an M12 bolt with an inside measurement of 44mm. I was going to use the pipe I mentioned as the pivot point on the ends of the wishbone, and pass a greased M12 bolt through. I welcome any ideas to improve this as I'm struggling a bit with finding something suitable off the shelf.

 

[rikrobson]

Are you not using a ploy or rubber bush on the wishbone? you could source a bush to fit into a tube that is at he end of the leg of the wishbone 44mm od will give a 40-42mm hole to fill with bushing then a tube 12mm id in the middle of the bush.
or use rose joints and space out with some 12id tube. using rouse joints will make them adjustable.

 

[Wobbly]

A bush would work, just spent half an hour but couldn't find anything though. Most spares shops list bushes by car/model but don't let you browse by dimension to find one a suitable size. The other idea I had was using a PTFE rod with a 12mm hole bored through the centre. I have found some the right outer diameter to push into 25mm x 2mm steel tube. Any thoughts on this?

 

[rikrobson]

PTFE would be too soft, You'd realy want polyurethane or rubber with a metal tube inside to hold the bolt. That's the basic way ford used to do it.

I'd be tempted to use rose joints, then space out the 44mm gap with m12 washers

 

[pedrobedro]

You want a kit car manufacturer like MNR. MAC#1 or MK sportscars who supply the poly bush, crush tube and the outer tubes as a set to fit the brackets you have bought. Your bush idea would work but you still need a crush tube for the bolt to go through and your bracket to clamp onto.

 

[aametalmaster]

I think a guy with a small lathe could do wonders for that job bushed or not...Bob

 

[ajlelectronics]

For poly bushes, have a look at Supaflex. http://www.superflex.co.uk/ I am sure I have seen plain material on there and maybe dimensions of ready made ones.

 

[Wobbly]

Thanks for all the suggestions, I'm liking the look of the plain material from Supaflex. As I'm on a tight budget, I reckon I could use a 44mm length of stock steel tube with an inside diameter of 1" then press in a 44mm length of the plain Supaflex 1" rod with a 12mm hole bored through to accept the bolt. As it's only a small buggy, and it's not going to work too hard, I reckon that would be fine.

One more quick question, what size stock tube do I need for an inside diameter of 1" with a 2mm thick wall? I'm a bit confused by the whole outside diameter x swg thing that the tube comes in. Thanks again

 

[Nivag]

Google BS3601, API5L and BS1740 for tube sizes and wall thicknesses. You can buy polyurethane round bar stock from Jobel or Watts.
Nivag.

 

[Wobbly]

Thanks Nivag, I had a look but it's all Greek to me.

 

[hotrodder]

Several stockholders have pages online showing all the different sizes stocked, Hublebas for example. Click on CFS (cold drawn seamless) or CEW (cold drawn welded) and do some sums. 25.4 OD is available with a 6.35mm wall for example which'll have an ID of 12.7mm (25.4 - 6.35 - 6.35). 1" ID with a 2mm wall would be an OD of 25.4 + 2 + 2 = 29.4mm. With the ODs and wall thickness available you'll have a choice of slightly under or over 1" ID

Googling 'metal swg' will get you a conversion table or the boiler section of the hublebas site list wall thickness by both swg and mm

 

[langy]

I'm not sure if this will be of any help but i sell polished stainless poly rodends, they are 5/8" unf thread and 1/2" hole

Personally i wouldn't reccomend rose joints for road use but if you do use them make sure you fit the dust seals with them, they will last a lot longer, oh and get good quality one's HTH

 

[Wobbly]

Thanks for the link Hotrodder, the sites I have been looking at for metal are very confusing for the novice. Langy, thanks for the pic but thats not really the thing I was looking for. The problem I am finding is that I'm not sure if the things I am thinking off actually exist, and if they do, what is the correct name for it so I can Google it.

One thing that I was thinking about last night was an easy way to attach a male rose joint to the wishbone to hold the hub in place. I am using 25mm square tube for the wishbones and I need a way to screw the rose joint into the end of the tube. First thought was to weld a small square of steel over the open end and then weld a nut to that plate. Then I thought about plugging the tube with some solid square section and drilling and tapping it. Which lead me to wonder if a premade insert exists that could be welded into the end of the tube. I found plenty of plastic inserts to blank the end of the tube, and some were threaded, but they were all plastic and not at all suitable for the job. Does a pre made threaded insert like this exist?

 

[langy]

I use threaded bungs to weld into tube as i use them all the time but all are for round tube, I'm not aware of any square one's available.
Round tube is much stronger than square for a wishbone, material should also be CDS.

Thanks for the link Hotrodder, the sites I have been looking at for metal are very confusing for the novice. Langy, thanks for the pic but thats not really the thing I was looking for. The problem I am finding is that I'm not sure if the things I am thinking off actually exist, and if they do, what is the correct name for it so I can Google it.

One thing that I was thinking about last night was an easy way to attach a male rose joint to the wishbone to hold the hub in place. I am using 25mm square tube for the wishbones and I need a way to screw the rose joint into the end of the tube. First thought was to weld a small square of steel over the open end and then weld a nut to that plate. Then I thought about plugging the tube with some solid square section and drilling and tapping it. Which lead me to wonder if a premade insert exists that could be welded into the end of the tube. I found plenty of plastic inserts to blank the end of the tube, and some were threaded, but they were all plastic and not at all suitable for the job. Does a pre made threaded insert like this exist?