Nodular Iron?????

[Degnol]

Is cast iron the same as nodular iron? I'm about to rethread a caliper bolt hole in a '77 LC knuckle and I've bought the "correct" drillbit to precurse the tap, but a metal working friend said that I ought to try to run the tap first. I asked if it was cast steel and he said "no" due to cost. Instead of using a helicoil, I'm just going to rethread with a 1/2" finethread.

So...who knows metal??

Thanks,
Ed

 

[bustanutley]

googled

"About Nodular Iron - Nodular Iron, also referred to as ductile iron, is typically the material used for heavy duty or racing applications of cast iron products. It is approximately 30% stronger than gray iron. "

so no, it is not the same thing as cast, but looks to be similar. Cast is also refered to as gray iron

 

[bustanutley]

Another

"DUCTILE IRON (SOMETIMES CALLED NODULAR IRON): A cast ferrous material in which the free graphite present is in a spherical form rather than a flake form. The desirable properties of ductile iron are achieved by means of chemistry and a fertilizing heat treatment of the castings."

 

[Pin_Head]

Nodular iron is a type of cast iron that is often used in differentials and knuckles. Nodular (aka ductile iron) has a higher tensile strength and ductility than common gray cast iron and is more machinable. My experience is that it taps easily.

 

[Degnol]

Yeah, the info I got was that if it taps with granular off fall, it is cast or nodular, if shavings, then steel. Anyway I'm going to try to run the tap w/o drilling first, unless I run into tap-breaking torque. Thanks for al the replies.

Google....who'da thunk it. Thanks, Nutley.


PinHead...priceless


Ed

 

[frenchman]

a bit of chemistry..........

nodular iron is one type of cast iron. when iron is processed to become steel it goes trought different stage. On one of the first stage of the treatment, we obtain all the different type of cast iron...nodular being one of them. the different type of cast iron are obtain by cobining different additive at different temperature. this type of material has a high percentage of graphite (carbon) in it.

if the mill want's to obtain steel instead of cast iron, the carbon needs to be remove so it is of a less percentage in the raw material. one of the process is to use propane gas so it can draw ''carbon from the material''.

if you want more info on it try www.matweb.com this site has a shxT load of info on any material.

yves

 

[Degnol]

Thanks for the link, Yves.
Ed