Boulderguy Posted July 28, 2014 Share Posted July 28, 2014 Annealing has as much to do with cooling as it does with heating. There are about 100 different types of aluminum and they all react differently to heat treatment. The point is without knowing the specifics of that particular piece it's monumentally irresponsible to put it in an oven, especially a part that can fail catastrophically. Link to comment Share on other sites More sharing options...
m sprank Posted July 28, 2014 Share Posted July 28, 2014 Heating and cooling of car parts to cause them to expand/contract for install purposes has been done since the first cars were made by hand before Ford built them on an assembly line. It is still done today. How do you install a sleeve? You heat the block until it expands and the sleeve comes out. No, I do not have exact metal content of the arms. But they are not 6061 which could be effected by extended temps in the 400 range. They are forged extrusions. Cast wheels are usually 356 and those are not effected by 400 deg cure times for powder coating. I do have thousands of miles on the arms after heating them. Link to comment Share on other sites More sharing options...
Boulderguy Posted July 29, 2014 Share Posted July 29, 2014 Heating parts made of mild steel is fine. And engine blocks are designed to withstand high temps. Heating aluminum suspension parts is a whole different beast. "We've done it that way for years" doesn't mean anything. You could drive 1000's of miles with propane in your tires, it still wouldn't be a good idea. It took the Hindenburg a year to blow up. The fact is you don't know how that piece reacts to heat. And there are plenty of alloys that can lose strength like this. So you're taking a chance that it's weakened & might fail catastrophically - as in might kill someone - and you're doing it with someone else's car. Saving yourself a few minutes of work isn't a good reason to take that chance. Some engineer spent a long time designing those control arms to meet exacting specs. And you think it's OK to put them in your oven? Might want to get familiar with the term 'gross negligence.' Totally, totally irresponsible. Look, if you really want to do this get yourself a Rockwell hardness tester & measure before & after to be sure. Shooting from the hip like that with a client's car tho, that's just not OK. Neither is giving that advice as an industry pro. Link to comment Share on other sites More sharing options...
m sprank Posted July 29, 2014 Share Posted July 29, 2014 You sir are confused. First, I did it on my OWN car. No one elses. Second, I did it 4-5 years ago. Third, car has never had an issue. Car is track ONLY. Fourth, I posted what I did for general knowledge. Other shops have chimed in over the years and they have done it too. Aluminum alloy arms are forged, not cast. I have never been able to find the exact alloy of the arms. Subaru has not given that info (so far). Back in 2002 a "colleague" gave me this info: 7075 approx w/ density of ~2.84 g/cc and a max yield strength of ~505MPa (T6 temper). I have never been able to confirm this. I have confirmed from multiple crashes that many times the aluminum arm is so stiff that the frame bends before the arm does. On a side note, you get motorcycle bearings out of the case by heating the case in an oven. The aluminum cases are the cheapest crap aluminum the OEM can find. When I raced professionally we had (literally) a 1970's/80's play and bake oven we used just for heating aluminum parts to make them expand faster than the steel that was pressed in. No one verified aluminum alloy content and I trusted my life to the machine every time I sat on it. Sometimes there is only one way to find out. Fire in the hole. Thats why we have test pilots. Enough cojones to try it. An engineering degree is only worth the paper it is printed on. Carry on. Link to comment Share on other sites More sharing options...
AZP Installs Posted July 29, 2014 Share Posted July 29, 2014 With all this being said, I personally wouldn't use this method because my wife is an attny and she wouldn't allow us to do it that way. The factory manual doesn't specify using an oven to remove the bushings so we usually use a press unless they've disintegrated so badly they just fall out -Mike Paisan http://www.pbase.com/paisan/image/153798190.jpg Maintaining, Modifying and Educating TriState Enthusiasts since 2001. Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs "Race Tested, Enthusiast Approved!" Link to comment Share on other sites More sharing options...
Boulderguy Posted July 29, 2014 Share Posted July 29, 2014 Actually an engineering degree gets paid pretty well, for good reason. It's disturbing that a guy selling high performance car parts doesn't have an appreciation for that. [mildly irritated comment deleted] Mike P. - smart wife I think the point's been beat up enough, I'm done guys. Best wishes. Link to comment Share on other sites More sharing options...
m sprank Posted July 29, 2014 Share Posted July 29, 2014 With all this being said, I personally wouldn't use this method because my wife is an attny and she wouldn't allow us to do it that way. The factory manual doesn't specify using an oven to remove the bushings so we usually use a press unless they've disintegrated so badly they just fall out -Mike Paisan http://www.pbase.com/paisan/image/153798190.jpg Maintaining, Modifying and Educating TriState Enthusiasts since 2001. Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs "Race Tested, Enthusiast Approved!" Like I said, I only did it to my own car and it has been "Race Tested". All cars at the shop get parts pressed out. I dont have an oven at the shop (other than the microwave used for food). As for engineers, I have said it before (many times)... after spending years of my life correcting their mistakes in the field, no I dont have any great love for people "bragging" about their degree. Link to comment Share on other sites More sharing options...
dark_templer_102 Posted July 30, 2014 Share Posted July 30, 2014 I'm just curious if anyone has bought the Group N LCA bushing from Rallispec recently? I placed an order a week ago and I can't seem to get in contact with them. I'm not sure if the wait will be a couple of weeks or months... If not Rallispec, is there any place that still sells Group N LCA bushings? Link to comment Share on other sites More sharing options...
m sprank Posted July 30, 2014 Share Posted July 30, 2014 I have not seen any in a long time. Link to comment Share on other sites More sharing options...
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