telescoping steering shaft

[johnneilson]

OK, I have been looking at a clean way to mount the rack and eliminate the bump steer issues.
I am contemplating mounting the rack to the axle, just no clean way to get the tierods around the radius rods and I need the room for my size 12's.
So, the steering shaft will need to move and or telescope. I could just have the steering wheel support bearing allow for some movement.
The standard double d shaft could perform this function but is not really made for this type of service.
Linear ball shaft assemblies are made for this type of service, anyone using something like this?

Thanks, John

[Joe Timney]

Over the years I have build 5 or 6 cars that way...no one EVER noticed that the steering wheel moved. Be sure to provide an anti-spearing stop on the steering shaft.

[Rex Schimmer]

John,
Try this link for McMaster Car linear bearing. The have splined roller shafts that might work for you.

http://www.mcmaster.com/#ball-splines/=aikyvg

Rex

[johnneilson]

Yes, did see the McMaster/IKO bearings. I have seen a very specialized 6 groove indexed shaft/bearing assy, very expensive.
I am just doing a sanity check.

Simple is better, usually.

John

[John Burk]

A trans output shaft and yoke would be less expensive .

[johnneilson]

A trans output shaft and yoke would be less expensive .

Are you watching me??!!??
I was just in the shop looking at a PG shaft and broken yoke.

I am going to work in the dark from now on............................yep, thats my excuse.

John

[will6er]

I think Flaming River and Borgeson both have telescoping steering shafts.

Will

[Stainless1]

We have the rack mounted on the axle on the little car and now the big car as well, we use a double d shaft to accommodate the movement just behind the rack.  Works well to absorb suspension movement without moving the shaft or steering wheel.  U joints at each end.  Depending on the angle your shaft runs it only slides an inch or less.

[bolesd]

John,
Another solution is a collapsible steering shaft made by Woodward, Model SCA 500.
Has about 9 " of movement and is actually intended as a safety column.
I am using this unit in my streamliner build with straight axle mounted rack and pinion.
                                                                                                               Dave

[johnneilson]

Dave,
I will take a closer look, Thanks

John

[SPARKY]

in the scrap bin at most dealerships you find strg colums---lots of the make noise in use and have to be replaced  I have several for the price of dumpster diving.

[12go3az]

john
we have rack mounted on front axle & use the slip portion of GM #19153614 shaft $69.00 new (has 4" of telescope)
also use 1 inside car to telescope for different size drivers. your GM tech will have warranty ones laying around. 
                                                                                                                            JIM

[38Chevy454]

New reply for an old post.  Saw this and thought about the Jaguar suspension I am swapping into a 53 GMC truck.

If you go to the junkyard, look at mid-80's and earlier Jaguar.  The entire front suspension (incl crossmember) is rubber mounted and so they use an adjusting length shaft between the steering column and rack.  The rack is mounted to the crossmember.  Since the steering column is fixed tot he body, the shaft has ability to change length small amounts.  It is splined both ends.  This might be a good low-budget solution for a telescoping shaft.  I estimate the Jag link could accommodate maybe 1/2 inch max travel.