Steering Rack and Column setup

The column assembly is removed wholesale from the donor Focus, and can pretty much be transferred as is to the MEV chassis and bolted loosely into place. The column will ultimately dogleg around the brake and clutch pedals in the final installation, but for the time being tie wrap the lower column shaft in place to stop it dropping onto your nice pristine floor panel.

 

The rack that was supplied needed to be cleaned up and treated to some TLC before being installed.

 

 

 

The rack is detailed here.

The unit is fairly widely used in the kit car world and offers a cost effective solution for the construction of the MEV Rocket.

 

The gaiters and rod ends are easy to come by and not expensive to purchase from pretty much any motor factor outlet.

 

 

 

 

 

 

With the Sierra rack bolted in place, you can get an idea of the take away angle of the column extension shaft.

Our solution to the extension is achieved by bolting in place a Grp 4 UJ and the double splined end column shaft from Rally Design. The pictures on the MEV CD for the Rocket show a solid short extension bolted to the rack, (origin unknown) welded to a shaft which has had flats ground onto sides of the shaft at the top to fit the double D clamp on the base of the Focus column.

Our installation has the extra UJ which will be adjusted and the shaft clamped to eliminate any articulation (looping) when the steering is rotated.

 

Construction of our column extension

Getting from the Focus steering column to the Sierra rack is so not easy and several different options were considered before deciding on the one we preferred. We did avoid what we affectionately refer to as the Sierra Cocktail stick steering shaft option.

 

The components to construct the extension are the original column link to the steering rack from the Focus, and a double splined end column shaft from Rally Design.

 

 

The large clamping block is cut from the origin Focus component.

The block did originally offer the option of using a customised double D shaft to make the top connection to the Focus column, but it would have been an expensive option..

 

 

2.5 inches of the original 19mm dia shaft in our option are machined to the same diameter as the Rally Design column shaft. We have chosen to use a sleeve around the two modified components.

 

 

The double splined end column shaft from Rally Design is cut in half and the plain ends are machined square in preparation for welding and insertion into the sleeve tube.

 

The sleeve tube is drilled in several locations then the shaft and sleeve are end and plug welded to make the final component. We used this process after seeing it successfully used elsewhere on another kit build website.

 

Because we need to support the column extension in its final position, our sleeve tube was machined to 20mm so that we can use a support bearing in the final installation. The end result is not necessarily be a thing of beauty, but it should be sturdy.

 

This completed component in our opinion will be fit for purpose. If you choose to follow the same method of construction, you must satisfy yourself of the same. You must under no circumstances take our description of construction as being definitive or in anyway endorsing an optimum design. If you have evidence that our design is flawed or indeed provides a certain vulnerability, we would be please to hear from you by email with your comments. We are human and will admit to our failings when presented with compelling evidence that we may be about to screw up. Thanks

 

 

We hunted around for a suitable support method and decided upon a 20mm bore rose joint which will be welded to the Rocket's chassis tubing to stop the multi jointed column from looping.

 

A search around on the internet indicated that we were looking at a quite expensive component until Randall Motorsport on eBay came to our rescue. We paid £9.75p (including delivery for our item), with which we are very pleased.

 

 

 

 

 

 

 

 

 

 

The Alternatives

Trawling around the internet got us thinking about the alternatives for the steering column extension. As long as we could get to a 9/16" x 36 splined UJ fitting for the Sierra rack we might be in business. As it turned out, although not a popular size in the USA, Borgeson and Flaming River both seemed to have such a uj, but it is pricey at $74 before shipping cost to the UK.

 

 

 

 

If we could marry up such a uj to a double D shaft we may indeed have a practical solution.

Borgeson, Flaming River and JEGS all seem to carry such an item at about $22 for a steel item, stainless costing two arms and three legs more. So costs for a DD shaft, a suitable uj and international a shipping made this a $180+ purchase. Prohibitive we felt, when we had other items on the shopping list we could buy out of that amount, if we used a home grown solution column as outlined above.

 

The internet provides all sorts of useful info, and in this case, we would direct you to the BORGESON website for their Steering System Design comments