The V8 Owners Forum -

Hi all,
could someone tell me if this looks strong enough ?

Basically I removed the outer adjustable shaft which is a spline fit over the main input to the Corsa power steering module.

I turned it down to fit snuggly into the Sierra shaft.

I then drilled and tapped the holes out to 6mm and put 2 high tensile bolts through from one side to the other.

The plan is to weld them and grind them flush, but is it strong enough??








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If I was using that approach, I'd have placed the bolts further apart. The two holes drilled so close may be a weak point

M6 certainly isnt big, and are they actually full HT 12.9 bolts ?


Assuming the piece shown is slipped down over another shaft, I'd have been tempted to cut two slits down the outer shaft, 180deg apart, then weld along it's length for a few inches. You'd be welding to the inner shaft and welding the slit closed again. Not that the latter would matter. But it would give a huge contact area for the weld and ensure lots of strength

The fact this work is on the loaded side of the column means it would need to be far stronger than the steering wheel side.

Still, I think if you were to to what you propose, and locked one side solid and had a 2-3ft bar on the other side, you would really struggle to try and shear two high tensile bolts. In fact, you'd probably struggle to shear a single bolt even down to M6.

But just using the bolts in shear when they arent actually a tight fit in the hole could lead to wear and shear over time. If I was using the bolts, I'd just use them as bolts and not weld anything.

Hi Steve,
thanks for the reply.

I could easily cut slots and weld it as you say, it wouldnt take much to do that as well as the bolts.
In my mind I assumed it wouldnt be too weak as the holes were threaded and therefore would be full of metal from the bolts.
I didnt want to rely totally on weld, especailly my welding

The whole sierra shaft needs to slide inside a tube with the mounting and switch gear on it. Thats why I was going to weld and grind the bolts, so they couldnt become loose and foul on the outter tube.

thanks again
Phil

Even with the bolts though, there will be some play between the bolt and the threads. This will move and enlarge every time the wheel is turned.

It would be different if the outer shaft was actually split and clamped tight, but this doesnt seem to be the case ?


Cutting a slit say 4-5mm wide open for 2-3" lengthwise leaves you room for a lot of weld. So strength is not an issue at all. And it would also be easy to create a fully round shaft again if something did need to go over it.

There would be no chance of failure that way IMO. Even 2-3" would be huge, 1-2" would be plenty. Just turn the welder up and burn the crap out of it. It's good clean solid metal so should be a doddle to weld

Would be a lot neater than what makes up the triangle section at the bottom of my column !!! lol Although mine is on the assisted side, so slightly less strain.

I needed to lengthen mine by about 15-20mm, so made up a new triangle section with some B&Q flat bar and lots of weld !

OK, so if I cut slots, weld it and use the bolts then this will be strong enough you feel?
thanks
Phil

I think if you cut the slots, weld along their length, the bolts would be doing nothing anyway.

Cheers Steve,
cut slots, all welded up and looks a treat!

Just got to figure out the other end now. Any clues?
Phil

What do you need to do there ?

Ive bought the original fitting, its not here yet:
http://www.ebay.co.uk/itm/271203600999? ... 1497.l2649

But I will need an end similar to the Sierra, or I will need the same size shaft as the sierra to fit into the bearing in the bulkhead and then a splined end to go to a UJ inside the engine bay.

I will have to take some pictures of what I have when the item above comes. But if you have any ideas that would be great!!
thanks
Phil

When i modified my solid propshafts, I used a solid 8mm dowel pin which was pressed via an interference fit through the two shafts - and then welded for good measure.

http://www.mez.co.uk/dcam/04300003.JPG

I thought the long end was going through to the rack ! lol

I'd just to something similar to Eliot. Get the two sections with UJ's and cut/join as required.


it is easy to think you need something much stronger and over-engineer it. But when you look at some OEM steering linkages, there really isnt that much to them strength wise. Just make sure any joins run true and dont wobble.