inconel install/machine shop full of rednecks
 

I took my FM mani and the exhaust side of my gt2560r to a machine shop down in Nashville last week to drill/tap (on a CnC machine) for Trackspeed's inconel studs. This is what I got back. They didn't drill deep enough for the studs to seat all the ways down. Only drilled as deep as the 8mm studs went, and tapped it. The studs bottom out inside now and if they go drill more they'll F--- the threads that are there, not a good idea. They though they could cut off wheel the studs shorter and I explained to them they'd be at it for an hour a stud and just got funny looks. They have no idea what or how hard inco is. The hotside comes scary close to the top of the lower stud. If I run it I'll dremel a little off the housing to make me feel better about the clearance. It's not a track only car. It should be my DD with a track day here and there is the plan.

Question is-Do I run this and never go back to the rednecks with hacksaws?

Make them buy me a new mani and go somewhere else to machine it? We all know this is probably the most difficult to actually pull off because we all know that no shop wants to fork over money for being stupid. Sometimes it's easier and cheaper to walk away.

Or run it and get a new mani later from Artech or someone later as an up-grade when money pours out my butt? And swap the studs to new toy.
Pics
https://www.miataturbo.net/attachmen...ine=1328912744

https://www.miataturbo.net/attachmen...ine=1328912744

https://www.miataturbo.net/attachmen...ine=1328912744

The wife things I should go back and throw it at someones head and ask for new stuff, I just want my damn car back on the road. Almost had it a year and almost never driven it.

Edit: Also anyone actually run a gasket in between the mani and the turbo? FM says they just blow out, but it could give me just a C hair more clearance. I have a metal one laying around from when the turbo was rebuild a few months ago.

Pics with turbo sitting on manifold?

did you actually verify if the holes are drilled longer than they are tapped? They might be able to tap another few threads in.

I can barely squeeze a business car on the stud. It actually dents the car a hair. If I dremel a bit off the housing it would probably be fine. Going out to the garage to pull a stud out and look in.
https://www.miataturbo.net/attachmen...ine=1328914288
https://www.miataturbo.net/attachmen...ine=1328914288

Drill deeper. Do it once, do it right, do it white.

Well, do it right so you never have to do it again.

Why do you need a machine shop for this? A drill press will do.

Do it right, do it yourself.

I can't see the pics from the first post, but on the fourth it looks like it sits flat. Is there a disadvantage to putting the nuts on when the studs first poke through? Other than increasing difficulty of installation, this may be a viable option.

Can anyone give me a good reason why they can't drill deeper and not F--- the threads up. They told me they can't go deeper now that the threads are cut cause if they drill deeper now it will mess up the threads that are already cut. I think they're idiots. Tennspeed.net gave them good reviews and now I want to go hit someone. My problem is I'm either way to passive of a person or I just start strangling people, just 2 modes. I need good reasons why this can or can't be fixed and why so when I go down there on monday I have good sounding valid reasons to make them fix this. I want this done the white way and telling them fix it or I'll kill you never goes well. Also I don't have a drill press so I can't do or fix this myself and they were going to use a computer controlled machine. I didn't want to mess this up on a home drill.

Edit: In my head when you drill to tap something you drill a hole smaller than the size you are tapping for. The hole drilled should be the diameter of the shank of the stud (the diameter inside of the threads). The tap is what cuts the whole larger for the threads to engage onto. So they should be able to drill just inside of the current threads and increase the depth of the whole and then start the tap on the current threads and start cutting. Am I wrong?

They're going to chew up the threads with the flutes of the drill bit, no matter how careful they are.

How many threads engage? And check to make sure they used a bottoming tap to get all the way to the bottom of the hole. There could easily be 3 full threads that you're not getting to.

You can cut inconel with a friction saw (cutoff wheel) it just takes a little patience. This is also partially your fault for not being clear about what you wanted with them. You always have to be clear with machinists, or you'll get back exactly what you ask for, i.e. drill these holes out and tap them this thread, doesn't mean drill these to a deeper depth, it means what you asked for. You also have to expect machinists to want to spend as little time as absolutely possible on any given project, unless it's for their own car, in which case they will make it 4 times as complicated as it needs to be.

It is somewhat my bad I guess. I thought it was self evident the studs need to be seated to the shank. What happened to people giving a s--- about the job they do? When I drill/tap something I measure the length a drill to suit or get a shorter stud. NOT drill and tap and then say well too bad.

By friction saw I doubt a dremel cut off and a beer will do. I don't want to ruin what is a good part. However, I see no way of this getting fixed unless I get a new manifold.

Dude, hit the turbine with a carbide burr if you're feeling really OCD, and run it. What's the worst possible problem?

Yeah, I think that's what I'll wind up doing. I'm going to be pissed when my studs back out and the turbo tries to fall off. I just know these F'ers will not buy me a new manifold even though they screwed me over.

Resbond the studs in and quit Hustlering yourself.

WHAT TAP DID THEY USE?

On the bottom is a standard tap, tapered at the tip, so if you bottom out the last bit doesn't get threaded. On the top is a home made bottoming tap, and the "store bought" bottoming tap is essentially the same thing. The taper is gone, the last few threads get taped, but it's difficult to use.
https://www.miataturbo.net/attachmen...ine=1328925587

I'm guessing they used a bottoming tap, otherwise the studs wouldn't go in hardly at all, but worth a shot. Mine is M10x1.25 though, yours are M10x1.5?

They can drill deeper without affecting the threads.

If they're a machine shop worth any bit of business they can do it. To drill and tap a hole the drill will be the diameter of the minor, or smallest part of the thread, the tap comes in afterwards and forms or cuts the rest of the thread. If you took the drill they used and put it in your current tapped holes there would be a few thousandths of tolerance on each side. Not a lot, but a mile if they have proper equipment and a cnc mill, point being if they do it right it won't touch the existing threads, and if it does there is still a tap coming in afterwards that will touch up if anything does happen. If they do barely touch the minor of the existing threads it won't affect you because your inconel studs, or any bolt, is grabbing half way down the thread at the pitch diameter, so you could lose a little material off the minor and never know.

Take it back to the shop and tell them.
-Lock it in their holding fixture and make sure the existing hole is square to the tool thats coming in.
-Put the snuggest pin they can in the thread to accurately measure the thread minor. If I knew the size of the hole or the inconel studs I'd tell you what size range to look for myself, its easy to find on google.
-Once the pin is in the hole use a co-axial indicator hanging from said cnc machine to find the center of the already tapped hole.
-Replace indicator with drill that is slightly smaller maybe .001-.003" smaller than the pin used, chances are its the same sized drill they used before.
-Drill the amount deeper you're not seeing your studs go in plus a slight amount extra maybe.
-Take the tap they've already used, start it in the existing threads so it doesn't mess them up, it will screw in like a bolt.
-Make them hand tap it down to the depth you'd like as such.

They fucked up already, make them earn it by hand tapping, chances are if they said they couldn't do it they couldn't do the last few steps in a machine.

Like everyone else said, make sure they finished with a bottom tap. And I find it hard to believe that a regular ol' cutoff wheel won't cut that ---- easily.

But then again, what's easy for some is difficult for others. I'm sure it's also quite 'easy' to ---- up the threads on your inco stud.

Personally, I would make sure they are tapped with a bottom tap then try cutting one shorter with a cutoff wheel. Dremel stuff will work but 4.5" wheels for stainless will be better. Put a nut on it first so you can unscrew it and remove the burr, then file it down nice n pretty. If you ---- it up, trackspeed may be nice and sell you one stud. I would be weary of trying to redrill and tap deeper; if you mess up those holes you will be worse off. 1 stud is cheaper than 1 manifold.

This. However, and I don't really want to get into a machinist's argument with you, but I could see their lack of desire to do this. The chips coming up the flute of the drill can damage the threads, and it's fairly difficult to set your zero on a threaded hole. Yes the pin works, but I'd be weary. I've succeeded in doing it myself, I've also failed though.

Also, coaxial indicators suck :P

If it were me I'd honestly do it in a drill press. That's where the floppy tolerances of a drill press come in handy. The fixture, head, and bit will flex before the side of the drill can do much damage.

Edit: also, you very accurately described how to do it correctly. I'd be impressed if a job shop like that cared enough to do it right. There's too many ass holes in the world.
Edit2: If I were the machinist at that shop, you better believe I wouldn't drill any deeper than what's already there. Too much risk for breaking through the casting, making the remaining material too thin, etc, etc. I would have asked the customer 3 times in a row "how much deeper?", and that's only if he asked me to go deeper.

^That's my issue. Why didn't I get a call. "Hey dude, FYI the studs are too long for the hole. Can i drill deeper or all the way through?" If it were me I would go at least go just a hair deeper. He did say when I picked it up he was scared to go all the way through to the ports. One of the holes aren't even cut all the way down, I just got back in from pulling the studs out. You can kinda see it on my second pic on my first post. It sticks up just a hair taller, but there is nothing on the turbine near that one. Also who the F^& puts red locktite on turbo stud? They covered the studs in the stuff, even I know that crap won't stay with the heat. I bet for my use it would be fine to just rebond the hell out of it and drive it. But, I'm ---- and want it done right. Just trying to figure how to "make it so".

Zissou basically said how it should have been done the first time. Which is basically how I would do it if I had access to a machine. Been a long time, but it isn't rocket science. I miss the drill press at my old shop that had a floating table under it. Wasn't CNC but I will own one when cash comes out in my urine.

Hustlering myself is my new phrase. He builds like I would like to build. Overkill. Copyright it Hustler

Any cutoff wheel will easily cut it. I cut a Trackspeed stud shorter with a freaking hacksaw in like 7 minutes. It's not like diamond or anything, just has much better heat properties than stainless.

Was laying in bed with this crap going through my head and remembered the old time-serts we used to use at the machine shop I worked at years ago. http://www.timesert.com/html/mtrcsert.html
They were great for replacing spark plug threads and exhaust manifold threads or just about anything a helicoil would be crap on. I might just order the right length in 10mmx1.5 and just drill and replace the whole thread. I would think they would hold up to the heat/pressure since they worked in aluminum sparkplug holes with out fail. If I remeber right we even used the carbonsteel ones in aluminum. I swear my boss even used these to hold in head studs, can't vouch for it because I never saw it, but he loved these things. I had completly forgoten these things.