If we, as the consumers, continue to flock to cheaper import parts, rather then pay for quality, then we should accept at least some of the responibility. My point is simply that people are too quick to sue anymore. Years ago if your neighbors dog bit you (talking a small bite, not a major tear) you went home, hated the dog, the neighbor appologised for it, and maybe they made you a plate of cookies. Now days before the dog even opens its mouth people are on the phone with their lawyers, then ***** about high insurance rates. Amen to that, in the long run you get what you've paid for. Chinese or not chinese parts.
rab71.......Thankyou for bringing this to the HAMB. This is important stuff and maybe saves somebody's life. Clark and Scoot........You guys nailed it on the head.
The Total Performace site is back up. Here is their Pitman Arm page. http://www.tperformance.com/street_rod_store/3200/224/?CFID=4945806&CFTOKEN=39770766 Compare the prices of the Corvair arms to Speedway. Total Performance:$40 and $65. Speedway:$53 and $85.
That's what I'm thinking. Has anyone got a good picture of a OEM Corvair arm ? Or any OEM pitman arm ? I'd like to compare the parting lines.
The pictures of the pitman arms on the TP site look like maybe they're cut from bar stock with very square edges. They don't look like the ones in Speedway's catalog, which look like they're either cast or forged. Also, the ones from TP say they're drilled to work with 1/2" spherical rod ends and the ones from Speedway are tapered from both sides to work with OEM tie rod ends (either on top or on the bottom).
If you look around Speedway has some shady business practices, they've taken and had parts they bought from US suppliers repopped in China and the price they sold it for didin't change. I look very carefully when I purchase from them. But it's an industry wide issue, there's a lot of junk out there. Hell even raw materials are getting bad. I had some Chinese steel sheet and it welded like ****... full of impurities. Ditto...
Without trying to get into a ******* up the wall contest, do the math. (someone here will be better at this than me). The scenario goes something like this, you take over a ton of metal and put it on wheels, you send it down the street at say 30 mph and all is well... until you come to a curve in the road ( it's not enough of a curve to warrant slowing down) so without slowing down you turn the steering wheel, say to the right. Now your one ton in a straight line at 30mph has become many many times one ton, you've just turned your front wheels to the right, most of that force is now transfered to the left front wheel and the parts that support and cause that wheel to turn. So the force is now magnified onto the left wheel structure. The energy that is stored in the movement of the car wants to keep travelling in a straight line. Now without a second thought you've turned the steering wheel and everything up the front end becomes stressed. For example;the hundreds of tons of force has just magnified to thousands of tons on the left front wheel. Turning a 90 degree corner is the same even though your speed is slower, the sharper you turn your wheels the more force you have to deal with, remember the car is naturally inclined to move in a straight line and it takes enormous force to make it change direction. As far as the definition of billet goes, we may be talking at cross purposes here. For an engineer (or blacksmith) "billet" refers to the type of square section metal above a certain size, over here it is 45mmx45mm or just under 2" square, so if you were to order 3"x3" steel section you would ask for billet instead of bar. So when you buy a "billet" part it refers to the size of bar it was machined from. Yes, there are many superior steels available, but at what cost. We have done forging jobs where a cube 3''x3''x3'' of complex alloy steel costs AUD $400.00. Automotive design engineers have many masters to please, they must select a type of steel suitable for it's purpose, if it requires heat treatment, that treatment must be a simple (low cost process). And the steel must be commonly available and low cost as well. And it MUST be the lowest weight possible. Remember these parts are made in the millions. (We have lost tenders for being 2 cents per part over budget). No doubt a pitman arm could be made from a cast material, however it would have to be larger (and heavier), and be heat treated, and as a result would cost about the same as a forged part. ( not to mention your fuel economy as you replaced lightweight forged for heavy cast parts). Also in the event of severe impact or shock the forged part will give way by bending thus absorbing and disipating some of the energy of the impact. Cast will not absorb or disipate, it fractures, and the energy is transfered elsewhere. I totally agree that every manufacturing process has it's pro's and con's. Automotive design and method engineers worked out decades ago that value for money, forged steel parts were the way to go, not only for their superior strength and performance but also their weight and cost per unit. I also agree that some Chinese maufacturing and quality control leaves a lot to be desired, however some blame must also attach to the people who asked for a part to be made as cheaply as possible, or, who when offered the parts at wholesale prices (to retail to the public) did not ask to see the Test Certificates and the relevant SAE standards applicable to that part. Maybe thats why they seek to avoid responsibility with disclaimers. As a manufacturer I am also annoyed at the asian invasion of cheap parts. When we start the manufacturing process for a new part we are required by law to undertake all the relevant materials and destructive tests. This can take up to one year and costs tens of thousands of dollars. This of course adds to the cost of each item. So a low cost manufacturer (without statutory regulations to follow) makes his parts cheaper (as well as a cheaper labour and overhead cost). No wonder you're retailers seek to avoid any liability for the parts they sell. Do you see any genuine parts with such a disclaimer? Of course not. Quality control is everything, you get what you pay for. The cheap thing is often the dear thing because it cannot do what you intended it to do, so you must replace it with something that can. Another tip I can give, all structural parts must be numbered. Some of these numbers are part No"s, some are batch No"s and some are the manufacturers. If a part dosn't have numbers don't buy it...... Please remember Hambers are'nt posting from six feet under.
Without trying to get into a ******* up the wall contest, do the math. (someone here will be better at this than me). The scenario goes something like this, you take over a ton of metal and put it on wheels, you send it down the street at say 30 mph and all is well... until you come to a curve in the road ( it's not enough of a curve to warrant slowing down) so without slowing down you turn the steering wheel, say to the right. Now your one ton in a straight line at 30mph has become many many times one ton, you've just turned your front wheels to the right, most of that force is now transfered to the left front wheel and the parts that support and cause that wheel to turn. So the force is now magnified onto the left wheel structure. The energy that is stored in the movement of the car wants to keep travelling in a straight line. Now without a second thought you've turned the steering wheel and everything up the front end becomes stressed. For example;the hundreds of tons of force has just magnified to thousands of tons on the left front wheel. Turning a 90 degree corner is the same even though your speed is slower, the sharper you turn your wheels the more force you have to deal with, remember the car is naturally inclined to move in a straight line and it takes enormous force to make it change direction. As far as the definition of billet goes, we may be talking at cross purposes here. For an engineer (or blacksmith) "billet" refers to the type of square section metal above a certain size, over here it is 45mmx45mm or just under 2" square, so if you were to order 3"x3" steel section you would ask for billet instead of bar. So when you buy a "billet" part it refers to the size of bar it was machined from. Yes, there are many superior steels available, but at what cost. We have done forging jobs where a cube 3''x3''x3'' of complex alloy steel costs AUD $400.00. Automotive design engineers have many masters to please, they must select a type of steel suitable for it's purpose, if it requires heat treatment, that treatment must be a simple (low cost process). And the steel must be commonly available and low cost as well. And it MUST be the lowest weight possible. Remember these parts are made in the millions. (We have lost tenders for being 2 cents per part over budget). No doubt a pitman arm could be made from a cast material, however it would have to be larger (and heavier), and be heat treated, and as a result would cost about the same as a forged part. ( not to mention your fuel economy as you replaced lightweight forged for heavy cast parts). Also in the event of severe impact or shock the forged part will give way by bending thus absorbing and disipating some of the energy of the impact. Cast will not absorb or disipate, it fractures, and the energy is transfered elsewhere. I totally agree that every manufacturing process has it's pro's and con's. Automotive design and method engineers worked out decades ago that value for money, forged steel parts were the way to go, not only for their superior strength and performance but also their weight and cost per unit. I also agree that some Chinese maufacturing and quality control leaves a lot to be desired, however some blame must also attach to the people who asked for a part to be made as cheaply as possible, or, who when offered the parts at wholesale prices (to retail to the public) did not ask to see the Test Certificates and the relevant SAE standards applicable to that part. Maybe thats why they seek to avoid responsibility with disclaimers. As a manufacturer I am also annoyed at the asian invasion of cheap parts. When we start the manufacturing process for a new part we are required by law to undertake all the relevant materials and destructive tests. This can take up to one year and costs tens of thousands of dollars. This of course adds to the cost of each item. So a low cost manufacturer (without statutory regulations to follow) makes his parts cheaper (as well as a cheaper labour and overhead cost). No wonder you're retailers seek to avoid any liability for the parts they sell. Do you see any genuine parts with such a disclaimer? Of course not. Quality control is everything, you get what you pay for. The cheap thing is often the dear thing because it cannot do what you intended it to do, so you must replace it with something that can. Another tip I can give, all structural parts must be numbered. Some of these numbers are part No"s, some are batch No"s and some are the manufacturers. If a part dosn't have numbers don't buy it...... Please remember Hambers are'nt posting from six feet under.
I'm an engineer, I did the math (at least the quick version ). And I agree, hundreds of tons of force in some instances, sure, but you're talking very high speeds, and/or very heavy autos before a steering component (that's not being mashed in a wreck) sees thousands of tons of force. Doesn't really matter either way, I was just tongue in cheek nitpicking. I'm a **** disturber at heart I suppose. Second, billet is a misnomer when used like this. Billet (manufacturing) From Wikipedia, the free encyclopedia Billet is a term used in manufacturing to refer to a cast product. A cast product is defined as either as ingot or a billet, depending on whether the cross-sectional diameter is greater than, or less than approximately 200 mm, respectively. A billet is typically cast to a geometry compatible with secondary processing, e.g. forging. An ingot is typically cast to a convenient geometry for further primary processing, e.g. heat treatment (Schey, 1999). Ingots and billets are collectively known as barstock What Wiki missed is that billets are then roll forged into bar stock. When it's done being processed, the billet is no more. Only roll forged bar stock, which is the only kind of bar stock you can buy. So, pretty much any piece of bar you buy will have come from billet. It's pointless to differentiate between billet and rolled bar stock, because by definition the latter has to come from the former. And since a billet is cast just the same as an ingot, it's not a good term to use to differentiate between cast parts and parts machined from solid bar. That's just a pet peeve of mine. Want to see something funny? Go over to the Practical Machinist board and ask a question about "billet" anything, especially when pertaining to motorcycles (for some reason). Hilarity will ensue, I promise. EDIT: I found this old post from Forest (cool old coddger from the Practical Machinist): "Billet" is a cl***ic example of common usage in a group noted for invincible ignorance triumphing over precise technical language. A "billet" is the term used to describe the material in its first stages of a hot rolling process. "The billets are heated then run through the first stand of rolls..." Before the billet was a billet it was a "bloom" and before that it was a "cast ingot." "Billet" is the material form in an intermediate step in the rolling process.
I don't disagree with the quality issues of stuff coming from China, India etc. Now that I've said that: Did we all just ***ume the pitman arm came from china or was that stated in the original post?
I was waitng for someone to get it. There is NO proof that the piece came from China. There is NO EVIDENCE as to what caused it to fail. So far, all we have is a broken pitman arm and a **** load of opinion. For all we know, some American company decided to cut their own corners.
Good point. We all (myself included) sort of jump to the conclusion that if something is cheap or substandard, China must somehow be involved (as if nothing cheap and substandard has ever rolled of the presses here in the US). Does anyone know for sure where these pieces are punched out? I for one am going to feel like I've developed foot-in-mouth disease if they're being made here.
We're a manufacturer as well and have lots of hidden cost that will end up in the final price of the product. Its a sin, when we quoted a job last week for a old customer of ours. (Lost the orders to a china factory in a reverse Auction )We could get the material 4.20 a thousand (302SS) for the target price (4.00)from a china spring house. Very sad....
I just got back from the Dominican Republic and some of the scarry things I saw down there really made me feel happy that we do have all the governing agencies watching out for our well being, such as lead paint, and actual traffic rules and the DOT. In the dominican, it really seemed like it was an "anything goes" kind of place regarding any kind of safety. I'm glad there was no death when this part failed.
But only to keep up with the lower costs of the companies in China. There..... anything to blame China, because we all know what is going on.
in one of those boring manufacturing magazines you find getting shipped free to companies all over the country, and usually sitting in piles all around the Human Resourses lobby there was a big article on how many companies that rushed to go overseas with their manufacturing operations are COMING back to the US because the cheap labor did not lower their operating cost .I wish I could remember the exact magazine but they named 20 companies that are moving back to US soil !All the hidden expenses finally exposed them selves like the rate of rework and s****ped product etc.then shipping ,tarrifs the list goes on and on and that includes the unspoken of bribes to the powers that be
I almost ordered one from S way one a few weeks ago. I think I'll polish my stock arm to remove any imperfections and paint it. Hey hey hey hey hey... Stayin alive
Ah, Coolhand quoting wikipedia indicates your are an educated man. Why do I have the feeling that you are using wikipeadia like a drunk man uses a lampost? More for support than illumination. I have broken-down (forged) 8 ton ingots into blooms and billets. Yes they come to the forge as cast.... but cast what? Cast alloy or plain carbon steel, not cast iron. The initial breaking down by forging under large presses reduces an uneven ingot to an even size for further processing and aligns the previously random ****tered grains into a recognisable grain structure, thus increasing the strength of the steel. Now the barstock manufacturers use the same process, but go on to rollform the billet into merchant bars. In the case of merchant square bar the sizes go from 6mm Sq (1/4) to 40mm Sq (1"1/2) then at 45mm Sq (1"3/4) the "bar" name is changed to billet. This change of name does not have any reference to it's ancestor, it is merely a way of refering to sections of steel above a certain size. Billet is not cast as an ingot is, billet is the product of the breaking down of an ingot by forging. So when a manufacturer decribes his product as machined from "billet" he is saying; this part has been made from one piece of refined steel, he may also say the cl*** of steel as well such as "alloy"or he may seek to make silk purses out of sows ears by saying "Machined from 1020 grade billet steel" sounds good does'nt it? When you consider 1020 is just mild steel. You say it is not good to differentiate between cast parts and parts made from billet, I have done so to point out your error. A cast part has no grain structure , hence less strength than a part made from billet or a part even further refined and strengthened by additional forging. Thank you for using "Forests" quote he proves my point exactly. Now would you please step away from that lampost and turn out the light.
Another metallurgical query on the whole idea of cast steering parts: Both ends of the pitman on most designs go over tapered parts, and are forced to advance on the taper by tightening a nut so that the tapers are a force fit, no longer separable without considerable pressure. This involves STRETCH of the holes, does it not?? Isn't that hole in effect acting just like a rubber band, forced outward by the fit and holding inward by its elasticity? Now what happens when (a.) cast iron or (b.) malleable cast parts are so stretched? Are they not in a position creating explosive outward forces if their limited elasticity is overcome by forces meant to be containrd in a forged piece? Is this anothe rpoint to worry about with iron? Found this out recently from a Ford researcher, confirmed it in my collection of s****: Early Ford pitmans were 100% tested for final surface condition as part of inspection before acceptance. Each arm has a small ground flat with a dimple mark from one of those penetration type, Brinnell or something, tests. Haven't looked over spindle arms yet. That might suggest something about the importance of this part...
If that was the case,the part would most likely fail where it is the thinnest;above the top hole,or below the lower hole.
I just checked the Speedway website. Not only are they not using those arms any more, they will be doing their own with a target date in April 2008 for shipment. Good on them and their quick response to the problem.
Being in the metals game for over 40 years I'm still trying to figure out how people can look at metal fractures or failures and tell in what country it was produced. It would help my company greatly if we could learn how to do this.
From the Speedway site: " CORVAIR PITMAN ARM <!--googleon:snippet--> We are no longer buying these from our current vendor. We are in the process of making our own forgings in polished and unpolished stainless which will be available for sale in mid to late April 2008. " Forged Stainless ? ? ? ? ? ? ? ? ? Socal Speedshop has Investment Cast Stainless axles,spindles, pitman arms,steering arms,shock mounts,etc in a few different alloys.Pitman arms are 17-4,axles are 316.
In my other life and p***ion not involving motor vehicles I am a blacksmith (not a Farrier)and yes Stainless steel can be forged many blade smiths do it.I personally have not tried it as yet but have seen it done many times in knife and sword making.I have managed to forge small pieces of solid bar from SS cable but I am far from ready to forge a useable tool from SS also I don't know if you can only do it from certain alloys of SS The cable I use was given to me by a pro bladesmith to practice with
So, you just said exactly what I did, but you used three times as many words and called me stupid while doing it. You obviously win this internet argument. Jack***. I know what they mean when they say billet, but they're using the word in the wrong context. It's a marketing hype driven *******ization of precise technical language. That's like saying someone got punched in their "grille". I know they mean their mouth or face, but someone who doesn't know the random slang in use at this time would be rather confused. When you're having a technical discussion, there's no need to devolve the interchange by interjecting random misplaced terms or slangisms (yes, I made that word up just now, to illustrate the point). Why would such a thing matter? 'Cause a great many people suffer from a problem with reading comprehension. You, for instance. This part in particular points to your lack thereof: Inside that quote you state that I said it's "not good" to differentiate between cast parts and parts made from billet. This is false. What I ACTUALLY said was that the term billet is a poor choice to use to differentiate between cast and cut from forged products, because a billet is a half step in a process, and comes from a casting. A different alloy than would be used for die or sand casting to be certain (sometimes anyway), but a casting none the less. I am partially guilty of poor proofreading myself, as the word from (in the brackets) should have been there, but is not. My fault, I think faster than I type sometimes (or most times). All you've proven is: 1) I need to proofread more closely. 2) You need to slow down and read the post more carefully before you puff up your chest and proceed to "school" someone. Also, just an FYI, there are a good quan***y of metallurgists out there that would disagree with your statement that cast parts "have no grain structure". Of course they have a grain structure. Unless you cool the molten metal so fast that crystals are unable to form and you get an amorphous blob (IE a gl***), there is a grain structure. The grain in a forging is just different from that of a cast part. Here again, your imprecise usage of the available language failed to convey the entire point (or even the correct point). This is exactly the kind of thing I'm talking about. If you know what you're talking about, then damnit, SAY what you mean and use precise enough language so that anyone can look at what you wrote and know exactly what you meant. It's even more important in text than in general conversation, 'cause in three weeks when someone drags up this thread again, you won't be there to explain what you meant when you used the terms incorrectly. And finally, if you're going to try to "tear someone a new one" (over the internet no less ), you must above all other things, read their post thoroughly to be sure you actually have a good grasp of what they are saying before you try to take it apart.
I have a question for you metallurgists. How does investment cast stainless steel compare to forged steel and cast iron? I'm thinking investment cast stainless falls somewhere in between the other two. It has a little bit of flex, so it's less likely to just crack in half like cast iron. But it probably doesn't have the ultimate strength of forged steel. But it's gotta be stronger than cast iron. I'm just wondering because I have investment cast stainless steel So-Cal batwings (or at least that's what I think they're made of), and I have a Speedway pitman arm on my Vega box that looks like it's made of investment cast stainless. Are they anywhere close to being as strong as they would be if they were made of forged steel? I know the alloy of the stainless would make a difference, but I just want to get a general idea. Am I correct that investment cast stainless has some flex and it's less likely to crack than cast iron? I know standard 18-8 stainless bolts are pretty easy to shear the head off compared to grade 8 or grade 5 bolts. I think they're roughly around the same strength as grade 2 bolts, so I wouldn't use them for critical applications. I'm not going to have fun driving if I'm thinking my pitman arm is going to snap in half at any moment, or a batwing is going to shear off. I'm hoping investment cast stainless has a little flex and a little springiness and toughness, so that it's not likely to just crack into pieces.
"Investment cast" is to distinguish from "Sand Cast". Better surface finish,more accurate sizes,still cast. Search on Matweb.com and compare Tensile Strength, Ultimate and Yield,and elongation at Break % for various metals.
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