ARTech welded steering pinion compared to another
 

A guy from Austin posed these pictures of his de-powered rack from a shop that does lots of spec Miata stuff.
Abe's work:
https://www.miataturbo.net/attachmen...ine=1312915650
The other shop:
https://www.miataturbo.net/attachmen...ine=1312915650
https://www.miataturbo.net/attachmen...ine=1312915650
https://www.miataturbo.net/attachmen...ine=1312915650
https://www.miataturbo.net/attachmen...ine=1312915650
I don't think I'd get in the car with that steering rack. It looks like the welds are too small, no penetration, and very little weld "bridging" the two pieces together.

On second thought, the pinion probably won't fatally break, but the welds will and the spline will stay together. It's still a Helen Keller weld and I wouldn't pay a cent for work like that.

Thats so dumb of that shop. They're obviously mig welds which would have taken about 2 seconds longer to make them longer, better welds.

I thought the tackweld pics were just halfway through the process.

Maybe I dont understand how power steering works correctly, but isn't that just the quill shaft? I didn't think you even technically had to have that welded to de-power a rack; it just makes the steering tighter.

Either pinion is more than acceptable.

First of all, the twist shaft core that activates the power steering spool is still active and in place. Centering the two main pieces, aligning them, etc. You will never lose steering since it is present.

And secondly you can see that both shops welded into the spline zone. Even if the weld(s) cracked all the way through there would still be no spline movement. Since they are now filled with material.

Beautiful welds are nice to behold. Like on some of those polished mufflers. Or on the Ariel Atom frame.

On further thought, perhaps the "shitty welds" were worried about warping the steering shaft? I know i'd want to be careful with heat in that zone.

I changed my mind a little bit. Those tacks look pretty substantial. It would take a lot of force to break one of those because there are four tacks. Of course, abes is of much higher quality, but I doubt those welds will break

It looks bad in the pic, but I don't think there's any real problem. Should be more than enough weld.

Instead of a full depower, one of the things I'm going to try on my car over the winter is removing vanes from the power steering pump. I want to lessen the assist (and load) of the system, but not fully eliminate it.

13 hr enduro - p/s = fail

I was pleasantly surprised how reasonable the steering effort is on a fully depowered / welded rack. It is way lower than a looped line quickie.

The welds on mine look shittier than that , but we did it under the car on a lift, and didnt clean it for shit. It gets the job done. I only welded it to take any play out of it.

For those of you who say it's "OK", you're probably right. This is the difference in a part that lasts forever and a part that lasts 5-years. Remember, I'm the guy who doesn't work on his track toy when globetrotting and setting records.

Looks amateur, but I don't see why it wouldn't hold. It took Abe not even 5 minutes to TIG the pinion all the way around on the original.

You do shitty work anyway, so who cares? I'd never trust anything you built. lulz

Maybe we could up the size of all the parts to perhaps double. And make them out of F1 / Mars Mission level material installed by ultimate ninja techs.

I love nice welds but this is just overkill based on not understanding how the pinion actually functions. A beautiful 360 TIG with before and after steps is probably 3 times stronger than the rest of the pinion or other steering parts from wheel to tie rod end. Sure it may only take five minutes. But it is no better than the 4 tack job also shown.

I know…lets all convert to 8 lug wheels. They are stronger!

explain this statement, please.

Karl from ART did those welds on the pinion shown in hustler's 1st post, which is mine by the way. It's not going to fatally break... if anything it will just go back to having slop like the video below...

http://vimeo.com/15245486

If it breaks I'll just take it back out and take it to a better shop. Thankfully there are no more PS lines to disconnect... just 5 bolts.

MotoIQ Article on Depower

Also, you'll notice in this other photo that one of the welds is cracked...

But, but, think of the weight savings! Gotta be at least 0.25g right there! :P

I bet one lap in my car would change his mind. You and I both have driven ghetto depowered cars, when you track mine at Hallett, you too will see the light. When Bond drove mine, I think his genetic legacy entered the excited state.

qft.

That rack scares me, I have already stuffed one car in the wall due to steering problems. A good way to ruin your day, week, month, year.

WOW!









I mean, who buys the retail box version of TurboTax anymore? That's crazy.

What exactly is it that you believe will occur here?

Well I'll be on my 3rd lap cruising around on a track day for charity, maybe driving 5/10's, then I'll approach the right handed sweeper at ~70mph, turn the wheel, keep going straight, hit a haybail and nearly flip. (2 wheel side balance, rallycar style)

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.

How much slop are we talking about? If it introduces a few unexpected degrees of steering angle at the wrong moment, it could still be pretty frightening, if not entirely catastrophic.

Did you guys take apart the steering components and examine what failed?

Exactly.

See my post on the first page. Video showing how much slop there is in a depowered pinion...

http://vimeo.com/15245486

1. Trying to race cars from the 60's.
2. Spline stripped.

It was a mini. Not a miata. But after one steering failure, you think twice. I have a manual rack in my car, I would never depower without welding the spline, all the way around.

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.

Those old Brit gears and splines are made of the finest Milk Chocolate money can buy. They keep the raw material chilled in Lucas refrigerators next to their warm beer.

How many Engineering disasters can you spot on this steering column shaft from a Vintage Mini?

Finally some common sense...

I like the new sjmarcy more than the old one. Global ignore works!!!

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.

in for ban.

lol.. you are drunk with power.

Honey badger don't give a shit.

And during business hours, for shame!

I believe that I'm fundamentally too immature to serve as an authority on an internet forum, lol. For this reason I only warn for grammar and retardation.

lol.... what's he eating the rest of the week?....................................






................cobra!

The thing is if the welds break in this instance it goes back to behaving just like the stock piece in terms of strength and all the steering load goes through the slender flexible shaft through the center that remains free of the heat affected zone from the weld pretty much even if you badly barbeque the outer cage as your welding it. This thing is two parts and The skinny center shaft is fixed at one end only by a small round cross pin. By welding it in this way your just fixing the cage around the center shaft so it cant twist as easily between the hard stops on the cage around it.

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 shit 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

Exactly. You have to understand what the heck is going on here.

I may try a nonwelding solution the next rack I rebuild. Then there is no chance of heat-warping.

JBweld the shit out of it?

Actually I would guess you would not be able to measure the performance difference between a welded one and one that heavily JB welded. Might not be a bad way to go. Wouldn’t have to worry about warping it either which is a serious concern.

FWIW the shaft between the rack and the firewall has a splined slip joint in it that is not clamped. To take the slop out of the splines they inject plastic material in it. I have found a cracked downpipe in the right spot will melt that plastic out and you will get play in your steering.

Bob

if the JB weld cracks and falls out in the rack, would there be anywhere it could go to mess something up?

It might get sucked into your Turbo. ;-)

Seriously, JB won't crumble. It might let go but it won't disintegrate and wreak havoc with anything.

If you look into a stock power steering pinion shaft in the area that gets welded, you'll see the splines.

The goal is to keep everything aligned while rendering that spline motionless. However it is done. It is not hard to do via welding and likely via compounds and inserts too. And that same spline and the central "twist" core whose motion we are trying to eliminate remain your safety backups.

The only reason i mentioned crumbling is because of turning forces and the back and forth vibration coming through the shaft. the JB weld in my experiance doesnt like vibrations.

I understand that you would ideally fill the splines with JB weld if thats how you go about it.

I think it would be hard to JB deep into the spline voids due to it being a thick putty. However something like Loctite Bearing Retain is thin and can weep into the openings via capillary action. And it is very strong. You could loctite and then insert metal pins into the spline voids. There is likely to be some sort of no-weld approach that will lock the shaft quite well. The first thing I would try would be the Loctite alone. One of the thin, green colored, high strength variations such as 640 or 680 off the top of my head. They wick, have gap-filling characteristics and are strong. They can only be removed via heat. The thing is…once you do a pinion shaft you'd then have to run it and beat on it to see if it holds up. I give it about a 75% chance. And a 100% chance of not warping.

I baked my pinion in the oven @500 degrees before I welded it. I did about half of the total circumference in quarters and then put it back in the oven to 'cool'. After about 5 minutes to normalize the temperature of the material, I did the other half in quarters and put it back in the oven again. I turned off the oven and let it cool slowly for a few hours while I did something else.

I'm sure it is overkill and a waste of time but reducing the temperature delta by ~450 degrees can't hurt. Mine didn't look as good as Abe's but it looked better than the other example earlier in the post and it didn't crack or warp at all.
-h

You may have partially annealed or tempered the part, rendering it softer.

Exactly. Softer = less brittle. I don't think the 500* oven is enough to drastically effect the metallurgy of the pinion but change in temperatures makes welds brittle. This may have made my welds less brittle by starting the subject hotter and making it cool less (and more slowly). It's been great for almost a full season. As noted correctly above, these aren't going to fail catastrophically anyway.
-h

What about brazing the shaft? It would involve less heat and should fill the splines with material. Its softer so I don't expect flaking.

You have to heat up significantly larger area of material to braze it although it is a much lower lower temperature. The thickness of the material around there will require a tone of heat in order to get the focus area up to brazing temp. Adjacent Thick material will suck the heat out of the area your trying to braze.

I have a tone of experience with brazing having worked building custom steel bicycles back in the 80's and early 90's. Brazing is phenomenal for thin wall stuff and I have done testing to show it better than tig welding in certain applications. Not so good for thick hunks of steel.

Tig welding with silicon bronze might a good way to keep the heat and distortion effects to a minimum. lower heat and still have a small heat effected zone.

Bob

Did anyone try the loctite or JB solution yet? When I pull my motor I really should explore removing my PS and would like to see what the results have been for these alternative methods.

[threadjack]

Where did you work, Bob? I've had a few custom steel bikes, some with brazed joints...I had a Landshark (John Slawta) road frame that had beautiful brazed joints with a really nice lugged bottom bracket and seat cluster.

[/threadjack]

I just Tig'ed mine a few weeks ago. 3 ribbons about 3/8 long. I didn't check it for warpage but it all went back together fine.

The gap filler loctite (for worn keyways) should work well.

I spoke to a mate about welding it up today - he didnt really want to do it just "incase" but both him and his manager suggested loctite 680 or 290. Has anyone tried either of these or have thoughts on the matter? I haven't had too much to do with loctite, so i'll have to do a bit of reading before i come to a conclusion.

cheers
plohl

I'm in the process of depowering the rack from my 1997 car. I'm going to give the Loctite 680 a try. If it fails, then I guess I can just clean it up and have it welded like everyone else. If it works in the long-term then it may be a viable option that we can recommend.

Here's a question though: Does anyone know what the actual diametral gap is between the two parts of the pinion shaft? I'm trying to decide whether or not to use the activator. It is recommended if you are near the gap limits for the retaining compound, but indicates that the ultimate strength of the cure will be slightly lower than if cured without activator at closer tolerances.

sorry I'm a little late for this. How much do they want?
I took a 2 sheets of 16ga mild steel and put one tack on them as a butt weld. It took 60 lbs to pull them apart.

2 Years Later...
 

Hey all, I'm in the process of installing power steering back into my Miata to sell. I bought an untouched powered rack and swapped it out with my depowered rack. For those of you just reading, the pictures hustler posted were of the pinion that's in the depowered rack for my car that Karl at ART welded.

I unbolted the pinion yesterday to see how the welds are doing and they look intact. This setup has been in the car for 2 years now with at least 12 track weekends on it. I'm not saying it's bullet proof but it has definitely withstood some forces applied to it. I'm attaching photos I took of the welds and how they look 2 years later...

Can I haz?