I am fabricating a steering arm for my g***er and I was told it has to be made out of a cast steel type material. I have already made it out of hot rolled 3/8 flat bar and was told it was going to be the weak link in my steering. I could use this arm as a pattern but have no idea what kind of steel to use. I'm using a 57 chev truck axle in a 57 chev car. any help would be great!
When i have had to make my own steering arm, i used stock arm or arms and modified or welded them together. Never made one from scratch. Hope that helps.
Hi Jim. I believe that H.R.S. is not only stronger, but also less brittle than castings. (it's "malleable") As long as your narrowest cross-section is not too small, I think it'll be fine. Of course, we can't just "think" it's OK when it comes to steering components...we gotta be sure...so take into account any contrary info to mine.
when you weld them together and fab one out of pieces, doesnt it become weak at the weld? speedways steering arms look like stamped 5/16 plate. Just when I thought I had it licked!!!
Yes, I think that welding can produce stressed and possibly brittle areas, but a good "annealing" should fix that. Basically, annealing is the process of heating metal to a particular temp, (above the recrystalization point) and then slowly cooling. It realigns the grains in the metal, and relieves stress from uneven heating or working. Damn...it's been more than 20 years since my material-processing cl*** though, so again...take my info with a grain of salt.
***uming you have a safe design and good weld quality,the 3/8 hot rolled is good material for a steering arm.Annealing or normalizing would be a good idea.
Sorry, the steering arm I'm referring to is the one on the p***. side. the car steers using the stock box w/ power steering pitman arm,speedway center link over to p*** side and connects to the fabricated steering arm.
Factory arms are Forged, not cast. Speedway had some steering parts failing, a couple years ago, that appeared to be cast.
Is this for a tri five ? If so most guys use one of there arms from the stock A frame front end. Sorry I cant remember which is used, left or right one.
So you are talking about an idler arm? It would see less stress in my opinion, as it's simply holding the center link on one end and pivoting back and forth, and all of the turning force is being consentrated on the pitman arm, as it's doing the actual turning. That's my opinion, but I could be wrong. And someone will probably point that out if I am.
Look at some of the bolt on steering arms that Speedway Motors sells. Sometimes easier and just as cheap to buy(steering is one place you don’t want to cut corners to save a few $$$). I have early Ford spindles on my 55. I bought a set of bolt on steering arms and bolted the left side to the p***enger side. In doing so, I also moved it to the top of the spindle to better line up with my pitman arm.When the car is sitting at ride height, you want the steering arm to be parallel with the ground (and the tie rod) to prevent bump steer.
i am not a steering expert, although i understand the statement about it being a weak link, steering items like a link or a arm get force in many directions and the force changes as the arm rotates and the car bounces up and down. the cross section of the fabricated arm needs to have full strentgh at the smallest point. i kind of think that 3/8 flat stock is just to thin, look at a bunch of drag links and steering arms and see how thick and small they are. i think the fabricated process is ok, but i would go to a medium carbon steel (4140) for more strength still weldable and you can oil quench at home. one reason casting maybe stronger is that the casting process has a tendency to round off and blend in corners. this blending will reduce stress points. also there are different grades of steel for casting just like for fabricating the steering is like the space shuttle one mistake and your life is on the line. brakes and steering are not the topic to make short cuts or be cheap.
Virtually correct, Baron. That left hand arm is one handy little devil! I have one on the right hand spindle of my '54 Ford Coupe g***er. My steering is behind the axle centerline, so my drag link goes to the right rear top of the spindle, ('41 Ford) with the lower arms still ther for the tie rod. Everything parrallel. Oh, my axle is a '33 Plymouth tube. Stock Chev p***. car arms are bolt-on, and have the same pattern for car & truck spindles.
Oh yeah...that's right...and forgings are quite strong. And H.R.S. is rolled under great pressure while red-hot, which is very similar to forging. Both processes form the hot metal under great pressure. I thought you were referring to a pitman arm. I don't see a problem with fabbing an idler arm with H.R.S. Can't find a replacement eh?
First of all ,who told you it had to be cast? Another HAMBER reminded us that factory steering arms are forged.
thanks for the pic mike, mine is similar where the arm bolts to the p***. side spindle topand steering from the rear of the axle. I have the original a frame suspension still but I thought the dimensions were different so I couldnt use those arms. I will check tomorrow. Thank you all for your comments.
I can't add too much new info that's not on here already, but I do have a concern about folks 'annealling' and 'tempering' things at home. I tend to hear the discussion go something like "just heat it up red hot with a torch and let it cool real slow." I don't recall finding 'red-hot' anywhere in an engineering text on metallurgy. There just isn't a good way of controlling the heat input and cooling rates with out a proper oven. The standard oxy-fuel torch can also add unwanted carbon into things. I've been trying to talk this idea out of the head of a coworker for a while. He wants to weld up a 4130 tube ch***is for a formula-type car and 'heat-treat' it with a torch.
1. The color of hot steel has been used to determine the temperature for a lot longer than cars have been around. I have seen the term red-hot in more than a few books on the subject. If I recall correctly, its mentioned in the FAA aircraft repair material, as well as several military repair reference materials. 2. Tempering at home is very do-able. Not to say that it is easy. 3. Lathe ways are heat treated with O/A torches. (all though it is in a very controlled manner.) 4. If you are going to heat treat a part, Normalize, temper, harden or anneal, you need to test the results to make sure the part you made has the desired properties. I would make two and destruction test one in a press, if you're going to try to harden and temper. Its a good thing Unkl Ian is around to straighten this thread out.
Another idiot proving that a little bit of knowledge is dangerous. Hopefully for his sake, he will balk at the price of 4140 tube.
That is known as "scotching" the welds to take the welding stresses out of the joints. You have to know what you're doing.. I've only heard of it being used by very experienced ch***is builders, which leaves me out of the equation. Bob
I would try to machine it in one piece and avoid any welding if possible. HRS and 4140 are both very strong is the as-supplied state. HRS is not something that is heat treatable, very similar to CRS in the carbon content. http://www.ehow.com/about_6508403_difference-hot_-_amp_-cold_rolled-steel.html Below are some good links for 4140 steel properties and the last link is good for anything that is welded and the recommended processing. Bob http://www.diehlsteel.com/alloy.aspx http://www.diehlsteel.com/4140sbd.aspx http://www.interlloy.com.au/data_sheets/high_tensile_steels/4140.html
a blacksmith can re-forge the end of a arm that well bolt to your spindle.a 'smith or smitty can srink the hole so you can re-taper,adjust the length and height.if you can't find a smitty a real good or better Farrier can do the same thing. when working in one of the oldest tool foundrys in the country i used to sneak LOTS of hotrod stuff through the production line. those old men loved to show off their mad skills to anyone that would watch. i can tell you the heat of metal by the color,straw color isn't as hot as red but they both will burn ya!
From the looks of the steering arm shown on pictures, looks like the bolts are in blind holes. FWIW, Personally I don't like the use of parts with blind holes on any suspension/steering component. I'd be interested in some of the opinions of the respondents regarding use of blind hole parts as opposed to through bolt and nuts. jack
If you're going to fab it out of 4340, for god sakes take it to a professional heat treat shop. Properly heat treating 4340 is a two-step process. You need to heat it and hold it at temp, followed by a lower-temp tempering process to restore toughness. Properly done, you can get 260,000 - 280,000 psi tensile out of it. Don't mickey-mouse HT in your garage, especially a steering arm!
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