ARTech welded steering pinion compared to another
#24
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I think sjmarcy's point is in Hustlers example picture, whilst the welds may not last, if they did in fact break, you wouldn't loose any steering ability, merely the lack of slop the welds are there to stop.
#27
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http://vimeo.com/15245486
#29
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I'd love to sell you some Miata pinion shaft insurance. Send me a PM for monthly payment information. Coincidentally sales are high and gross profit is 100% as there are no shafts breaking and there won't be any.
The stock power steering pinion shaft transmits torque through a skinny shaft or rod deliberately designed to twist as effort rises until it can no longer do so. This rod sends more high pressure fluid to the rack as it actuates a spool valve. It cannot move past a certain amount of rotation or twist due to the separate spline device elsewhere on the assembly hitting its stops. This spline midway on the shaft (barely visible) is where you weld and is not to be mistaken for the steering input shaft spline to which the steering column attaches.
The amount of skinny rod twist is in the neighborhood of 3/4 inch of play at the steering wheel, but this is only when input torque is high. If input torque is low then there is no play since the skinny twist rod doesn't twist at those times.
You can examine a pinion shaft at the steering input end. See that hole? That is where a steel pin passes through the hollow upper end of the outer shaft to retain the skinny twist shaft within it so that it can transmit torque. Further down the skinny rod attaches to the pinion end in some manner.
Stock, the torque can only go through the skinny twist rod and the center located spline when it twists all the way. Welded and there are then three paths. The skinny rod in the core. The two main shaft at their now filled up splines. And the welds themselves.
If the welds failed (all of them), and all the weld material disintegrated and rematerialized into Fort Knox (empty), you'd still have steering. But with about 3/4 inch of play using the stock unaltered bits that remain fully functional. Back to where you started and just as safe. However, the weld material jammed up the splines. Hence you would never get all that play, you'd still have none in that region.
Peace of mind is priceless, so do what you're gonna do anyway and just ignore me. If you need some aerospace welds performed by former Space Shuttle techs begging for change at the street corner, great. They can use F1 welding rod and have the Pope bless the steering rack. And of course you'd have the insurance policy I just sold you. Backed by the full faith and credit of the USA. Wait, what?!!
I'd switch to 8 lug hubs and wheels before I'd worry much about this issue. After all 8 lug setups are stronger. I don't want to have a wheel come off the car.
The stock power steering pinion shaft transmits torque through a skinny shaft or rod deliberately designed to twist as effort rises until it can no longer do so. This rod sends more high pressure fluid to the rack as it actuates a spool valve. It cannot move past a certain amount of rotation or twist due to the separate spline device elsewhere on the assembly hitting its stops. This spline midway on the shaft (barely visible) is where you weld and is not to be mistaken for the steering input shaft spline to which the steering column attaches.
The amount of skinny rod twist is in the neighborhood of 3/4 inch of play at the steering wheel, but this is only when input torque is high. If input torque is low then there is no play since the skinny twist rod doesn't twist at those times.
You can examine a pinion shaft at the steering input end. See that hole? That is where a steel pin passes through the hollow upper end of the outer shaft to retain the skinny twist shaft within it so that it can transmit torque. Further down the skinny rod attaches to the pinion end in some manner.
Stock, the torque can only go through the skinny twist rod and the center located spline when it twists all the way. Welded and there are then three paths. The skinny rod in the core. The two main shaft at their now filled up splines. And the welds themselves.
If the welds failed (all of them), and all the weld material disintegrated and rematerialized into Fort Knox (empty), you'd still have steering. But with about 3/4 inch of play using the stock unaltered bits that remain fully functional. Back to where you started and just as safe. However, the weld material jammed up the splines. Hence you would never get all that play, you'd still have none in that region.
Peace of mind is priceless, so do what you're gonna do anyway and just ignore me. If you need some aerospace welds performed by former Space Shuttle techs begging for change at the street corner, great. They can use F1 welding rod and have the Pope bless the steering rack. And of course you'd have the insurance policy I just sold you. Backed by the full faith and credit of the USA. Wait, what?!!
I'd switch to 8 lug hubs and wheels before I'd worry much about this issue. After all 8 lug setups are stronger. I don't want to have a wheel come off the car.
#30
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How many Engineering disasters can you spot on this steering column shaft from a Vintage Mini?
Last edited by sjmarcy; 08-10-2011 at 12:23 PM.
#33
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My ghetto rack works fine, and so do my Taiwanese coilovers. Fancy racks and xida's would be appreciated, but lets. face it, none of us are good enough to extract the full potential of our cars yet anyway. This topic is moot. Pretty welds are pretty. Can't die from it. Won't go faster with it.
#34
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My ghetto rack works fine, and so do my Taiwanese coilovers. Fancy racks and xida's would be appreciated, but lets. face it, none of us are good enough to extract the full potential of our cars yet anyway. This topic is moot. Pretty welds are pretty. Can't die from it. Won't go faster with it.
#40
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I have done this mod and I can say the crummy welds don't scare me at all. The most difficult thing about doing this is welding it without it warping. You would have to be dam lucky to get a continuous bead around the thing without it being warped when it cooled. I put a beautiful tig weld all around one in small increments and it came out warped as **** luckily I had a spare to try it again. If it warps you get tight and loose spots in the pinion adjustment to the rack and it feels horrible. The small dabs at 4 locations might be the best way to do it to avoid warping it.
Bob