Re: Hard Cranks

[farna@xxxxxxx]

If AMC used the same high nickel content iron in their cranks as they did their blocks, then the cranks would be a bit harder than other makers stock cranks, just like the blocks. I don't know what others used to make their cranks though, might have used higher nickel iron for cranks and just skimmped on the blocks. 


On February 20, 2005 Bruce Hevner wrote:

> Lynn,
> >Well, I'm glad to see that I have generated some chatter across the ether.
> Some people think that nitriding is super expensive, but it is not. In fact,
> we >nitride BY THE POUND, with a 100lb. minimum.
> >Therefore, the more cranks we have in a run, the cheaper it is. Example: if
> you sent a crank from Ohio to the shop in Portland, Or, and did not have a
> >UPS account, it would run about $170 to ship the crank both ways. (We
> prefer Forward Air) This is more than $100 over the cost of the nitriding.
> 
> Well that's certainly a LOT cheaper than it used to be (I haven't checked in
> years). I think it used to cost about $250-$300 EACH!! Don't get me wrong
> I'm NOT against this process,, I'm FOR it, IF it can be done at a reasonable
> cost and IF you can guaranty straightness. We were experiencing .002-.004
> bend from end to end. It WILL reduce wear of the crankshaft. In fact I have
> a 390 crank that was Hard Chromed YEARS ago that I might send you to see if
> it can be saved. Do you have a hardness tester?? Shoot me some numbers.
> 
> >We feel that any crank that might be cut beyond the factory hardness level
> will be better for the process. (does anyone know what depth the AMC >cranks
> were hardened to from the factory?
> 
> That was my question in the beginning. WHAT IS the hardness level of factory
> AMC cranks?? I contend (though I can not prove since I have not had one
> tested) that they are no "harder" than any other stock crank. I may be
> wrong,,, but I MAY be right (cue the Billy Joel music!!).
>   It's really pretty easy to get an idea of the hardness of an item,, just
> give it the "file test". While not scientific by any stretch it does give
> you an idea of the general hardness of an item.  A Nitrided item (and I am
> fully aware there are different levels of hardness that can be obtained) is
> difficult or impossible to file with a common hand file. It will feel like
> you are trying to file a piece of glass!! Just slides right over it. This
> has NOT been the case with ANY of the AMC cranks I have checked.
>  And of the Honda cranks we have turned that WERE nitrided the thickness was
> less than about .003.
> But hey,,,, that's just ME!!
> Bruce Hevner
> 
> 
> 
> 
> 
> .


=============================================================
Posted by wixList Archiver -- http://www.amxfiles.com/wixlist