Threaded rod in grade 12.9. Any sources?

[Turbo6Smackdown]

I'm looking for some threaded rod or set screw in grade 12.9 or higher in M10x1.25. Does anyone know where I could get some of this? I can't find it anywhere All I find is 1.5 thread, or if I find my size, it's super cheap steel.

 

[ijames]

How long? Best I could find quickly was grade B7, tensile strength 124 ksi vs 170 ksi for 12.9, in 0.3 and 1 meter lengths. That was at www.McMaster.com. They have socket head cap screws in 12.9, fully threaded, up to 40 mm long. If that's long enough you could cut the head off to make a stud. Call Maryland Metrics and ask them (www.marylandmetrics.com).

 

[Turbo6Smackdown]

I need about 7 inches of it. Gotta be 12.9 or 10.9 strength or it's worthless. I'm making my own studs. I need, I think three, 50mm long sections of it.

 

[pacecarta]

have to ask ..what are these studs for ?

 

[Turbo6Smackdown]

My turbo that my mechanic messed up the threads on. See here:

http://www.turbobuick.com/forums/threads/why.410819/

 

[pacecarta]

http://www.treadstoneperformance.com/product.phtml?p=68019&cat_key=305&prodname=M10 X 1.25 42mm Stud

but im old and recall those studs for our turbo are supposed to be M10x 1.5 and ive used GM hardware bolts before from other locations without issues , dont know why you feel you need 12.9 grade hardware

 

[Turbo6Smackdown]

http://www.turbobuick.com/forums/threads/what-size-thread.410821/

I need a little longer because before I send this to Bison for an overhaul (after precision JUST did it) I want to continue to use it. I couldn't thread a long bolt thru the back side because of the turbine itself-it won't let a bolt that long thru because of the angle. So I'm going to thread the threaded rod into one side, while I hold a nut and washer on the back side. Now I have a stud sticking out of the bottom like it's supposed to be. I just don't trust the threads because they're partly mangled now. So I'm just doing this to reinforce the thread contact area. I'm afraid if I utilize standard studs, I'll pull one out of the turbo because of the messed up threads. I was told that this will never re-seal now (using normal bolts like what's in there now) so I'm kind of wanting to get some good clamping force on there for now. I thought this sort of stud was the only way.

 

[ijames]

If they said it wouldn't seal because the flange surface isn't flat, then just fix that. If it was because of the mangled threads, use a longer stud with a nut on top like you planned but you don't need 12.9, 8.8 will be plenty because that's already better than what GM used. Get one of the Remflex turbo gaskets for insurance, and don't over tighten the bolts. I know at least a couple of the vendors here sell them, or you can order direct.

[PS Yes, I'm bored, so I did some quick and dirty calcs and 8.8 10-1.25 will give at least 6000 lbs of clamping force at a 50% yield margin, and a rough estimate says it will take about 5-8,000 lbs of force to break off the corner of the flange, so I can't see where more than that will gain you anything.]

 

[Turbo6Smackdown]

Gm's studs weren't even 8.8? Really? I didn't know that-that sucks lol. And I already have a gasket. One of those copper deals. I just got paranoid because someone on here said that once that bolts out, the seal's broken, and it'll never seal now. Hence my search for something that will allow me to really tighten the shit out of it. When I do something, I go as far as I can possibly go. I try to pull out every stop I can within reason.

 

[ijames]

I'm going to take back that not 8.8 from GM; I've never actually tested one but also never noticed that they were particularly hard so always assumed about a 6.8. They aren't mush like a 4. As far as "tighten the shit out of it", as much as it pains me one of the things I've finally learned over the years is that that is counterproductive when it comes to flanges and seals, sigh. It just leads to warpage, cracks, and worse leaks, along with stripped threads and broken bolts. As much as I love breaking bolts by over tightening, I hate fixing the result . I do get a strange pleasure out of tightening a 1-5/16" trailer hitch ball with a 12" crescent wrench because I know I can safely pull it as tight as I can and not break the bolt .

Once you tighten up a pristine flange you probably get a slight bulge around each stud, and more if you extract the stud, so the flange isn't quite flat anymore, which is my guess at what that person meant. If you have all three studs out, take some fine sandpaper on a piece of window glass or a very flat metal plate, and lightly sand the flange. You will see how flat it is, and just touch it up as needed and it will be fine. Do the same for the header flange - it is probably warped worse than the turbo flange. When you assemble it, only torque to the GM spec. More and you will just start bending the ears on the flanges (mine have the corrective sanding marks to prove it ).

 

[Turbo6Smackdown]

I did plan on sanding it for sure. I am a flatness freak too lol. Once I have the turbo off I'll make that happen before I send it out. Thanks for your help.