Assuming you have a choice, which is better, performance-wise? What do *you* prefer and why? In this case, I can go either way and price is a wash; 4" long 3/4"-36 splined shaft compared to 18" long (I'd only need about 4") 3/4" Double D shaft. Thanks, fellas!
I have used double d shaft, cause I'm lazy, and can guess the length when ordering. But, I gotta believe splines are superior.
I would use splines. Double D is around mostly because it's easier. It came into common use as OEM around the time that collapsing steering columns were required, in the late 60s.
I only used DD on the end where the original steering shaft is cut off. if I could spline a steering shaft with my grinder I would spline that one too.
^^^^^^^^^^^THIS^^^^^^^^^^ Not only do I like the adjustability of the splined shafting but I think it just looks cleaner. It is more expensive and that is why it's best to have everything finalized. A length of 3/4" wood dowel whittled down to fit the splined joint is what I use. Study the Borgeson, Flaming River online catalog for available lengths (custom lengths also available). I like to figure it so the exposed spline is kept to a minimum, excess overall length is easily trimmed off.
Manufacturers did use DD's for a long time on their collapsible steering columns.. I think DD's are fine, yes, splines are probably better....
Since double d has a near perfect 60+ year safety record , I see no reason not to use it . If you like your stuff to look more " mechanical" , that's fine as well ..
I've always used double D's... with a file and some patience it's easy to get the flats cut on the end of round stock. Do it right and no one can tell that it isn't splined.
Splines are awkward in that it is hard to measure what you have. Sometimes they Don't go all the way around with a notch for the pinch bolt and you have to guess what the spline count should be. I always wonder if I ordered right until it shows up in the mail. Sent from my SM-T350 using The H.A.M.B. mobile app
How in the hell can the application of an axle shaft and steering shaft be compared? One sees 1500 ft lbs of torque and the other might see 50 ft lbs on a really bad day. Splines that are tapered fit such as pitman arms and steering wheel centers are a zero play joint. Straight splines aren’t.
You don't need to count all of the splines. Find the center of the shaft and scribe a line across avoiding any area with missing splines. Count splines on the complete half and multiply by 2.
I was in no way trying to compare the job of an axle shaft to that of a steering shaft. But I will remove my offensive post.
I use DD joints for the convenience of using a DD intermediate shaft, easier for me to cut to required length. On my 35 I had a friend machine DD ends to some SS round bar. You can't see it behind the headers anyway. My 46 intermediate shaft is a collapsible 1"-3/4" DD shaft below support bearing as required by the engineer down here. I couldn't be bothered having some SS round bar machined to DD as per 35 to connect to column so DD it is. You won't see anyway, at least it's consistent with all DD fittings from column down to steering shaft. In saying that I used quality Flaming River & Borgeson joints, not cheaper Chinese joints, as they are approved down here.
For sure!! It’s pretty easy to take a round shaft, cut to length, and create the DD profiles at will within minutes with minimal tooling and indexed as one sees fit. It’s Quite a bit more involved to create splines. Most steering columns come with splines on both ends as do most steering boxes. That is three indexes to play with if you need them.
I like to use 3/4 cold rolled and add DD to the ends on the Bridgeport. I don't care for the look of lengths of DD shaft. Ron
I came across this thread doing a search. Here is some useful info. https://www.borgeson.com/steering-system-design-and-tech
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