Part mounting questions

[Pevehouse]

I have a Burke mill and self teaching myself. Home shop. Mostly from hands on and internet searching. I have an older Ford 460 truck. I rebuilt the engine several years ago and never could get the exhaust manifolds to seal well. Was told the cast iron exhaust manifolds on the 460 warp and after removing they won't be flat. I was thinking of giving it a try myself. Thinking of using a fly cutter and truing them up.

For the new guy to machining, how do you mount something that is practically round and not flat? I do have a hold down set, but what kind of shims? Most of what I have machined so far has been ether clamped flat or held in a vise.

I did this a while back and got tons of feedback on here. I just mounted it flat to the table and used whatever I could find to true it up. Gonna need a way to make sure it’s perfectly level to the spindle, side to side and fro t to back. I’m sure one of the machinists here will help you out

 

[Pevehouse]

Kinda funny coming from a machinist forum. I am pretty much a DIY guy. Every time I take something in, I am disappointed. I could do a better job a lot cheaper. I just finished working on a friends car. The shop that did the last alignment left one of the lock nuts loose. Last time I took my truck in for an alignment (decade ago) they left the connecting sleeves loose. By the time I caught it, they backed out quite a ways and ate up the threads and destroyed the tires. Shop manager had the attitude I loosened them.

View attachment 488969

As a suspension and steering guru myself, I see quite a lot of what you’re explaining here and I understand the frustration there. It’s extremely hard even in our area to find a good alignment tech, that is one reason I stay so busy I n my day job. As for the manifold I also understand wanting to do it yourself. I say go for it. I had good luck with my experience however I did have a badly warped manifold and had to take way more off than I liked. That’s one thing to be cautious of. Taking a lot off may leave you with something that’s gonna warp back up very easily. Then there’s the fact that it is a seasons cast iron part that may never warp again. Hard to say. Just food for thought. I can say with a rotor it’s best to throw them out nowadays than to try to salvage them. The castings are so close to spec already. Any how I hope you have good luck with it

 

[B Mann]

I would try to fab up some kind of mounting block where the manifold could be bolted through all the mounting holes at the same time.

Then as you mill down the length you can remove one hold down bolt at a time. Mill over that spot and replace the bolt before removing the next one. Leap frog style progression.

Using studs instead of bolts would let you put a double nutted support under each mounting ear, even if they are different heights.

I hate to stop and start, but seems like the best idea so far. The bolts are 3/8, but the holes maybe closer to 7/16" so the larger bolts or studs may give it better support.

 

[Downunder Bob]

This a 460 manifold, But I don't think mine is even this flat on the back. Just wanting to add a picture and seen the replies.
View attachment 488942

Ok now I can see the beast. I would mount it on the mill table with the flange faces down and see where it touches. Bolt it down at the contact points try not to distort it, place shims under high spots. Now mill 2 or 3 flat s[pots on the ridge at the back. They need to be large enough for positioning on 123 blocks or similar, or maybe machinist jacks.

Now flip the part and set up on blocks or jacks on the flat spots you have created, securely clamp the manifold down and you should be able to lightly mill the flange faces true and square, taking only the minimum off that you have to to get a new surface. Job done.

 

[Pevehouse]

Ok now I can see the beast. I would mount it on the mill table with the flange faces down and see where it touches. Bolt it down at the contact points try not to distort it, place shims under high spots. Now mill 2 or 3 flat s[pots on the ridge at the back. They need to be large enough for positioning on 123 blocks or similar, or maybe machinist jacks.

Now flip the part and set up on blocks or jacks on the flat spots you have created, securely clamp the manifold down and you should be able to lightly mill the flange faces true and square, taking only the minimum off that you have to to get a new surface. Job done.

Now that sounds like a good plan

 

[Danzo187]

I have a Burke mill and self teaching myself. Home shop. Mostly from hands on and internet searching. I have an older Ford 460 truck. I rebuilt the engine several years ago and never could get the exhaust manifolds to seal well. Was told the cast iron exhaust manifolds on the 460 warp and after removing they won't be flat. I was thinking of giving it a try myself. Thinking of using a fly cutter and truing them up.

For the new guy to machining, how do you mount something that is practically round and not flat? I do have a hold down set, but what kind of shims? Most of what I have machined so far has been ether clamped flat or held in a vise.

I'd find a local woodshop and ask to lay it on their big ol Belt sander,offer a little cash or trade for some machinist work

 

[B Mann]

As a suspension and steering guru myself, I see quite a lot of what you’re explaining here and I understand the frustration there. It’s extremely hard even in our area to find a good alignment tech, that is one reason I stay so busy I n my day job.

OK, this never posted from the other day... Hmmm

I am going over my friends shop estimate, most of the parts look pretty good. I can see knocking out outer tie rods, but both inner tie rods in the rack are bad?? I have replaced 100s of outers, but never an inner. (in a rack). Not sure if the mechanic just said these are usually sloppy and said replace without even looking at them. (or testing) The control arm bushings are a year old and look almost new. (I know a shop gets busy but... and this estimate was for a woman)

 

[B Mann]

Ok now I can see the beast. I would mount it on the mill table with the flange faces down and see where it touches. Bolt it down at the contact points try not to distort it, place shims under high spots. Now mill 2 or 3 flat s[pots on the ridge at the back. They need to be large enough for positioning on 123 blocks or similar, or maybe machinist jacks.

Now flip the part and set up on blocks or jacks on the flat spots you have created, securely clamp the manifold down and you should be able to lightly mill the flange faces true and square, taking only the minimum off that you have to to get a new surface. Job done.

That does sound like a good idea. Thanks.

 

[Pevehouse]

OK, this never posted from the other day... Hmmm

I am going over my friends shop estimate, most of the parts look pretty good. I can see knocking out outer tie rods, but both inner tie rods in the rack are bad?? I have replaced 100s of outers, but never an inner. (in a rack). Not sure if the mechanic just said these are usually sloppy and said replace without even looking at them. (or testing) The control arm bushings are a year old and look almost new. (I know a shop gets busy but... and this estimate was for a woman)

Inners are no problem. I’m sure you could pull that off yourself. Just a matter of removing the bellows and then the tiered. They just thread into the racks main shaft. Use lock tire when you go back with them. Blue would suffice. There are several tools that would make the job easier but depending on the vehicle a pipe wrench could work.

 

[Pevehouse]

OK, this never posted from the other day... Hmmm

I am going over my friends shop estimate, most of the parts look pretty good. I can see knocking out outer tie rods, but both inner tie rods in the rack are bad?? I have replaced 100s of outers, but never an inner. (in a rack). Not sure if the mechanic just said these are usually sloppy and said replace without even looking at them. (or testing) The control arm bushings are a year old and look almost new. (I know a shop gets busy but... and this estimate was for a woman)

You will of coarse need to get it aligned after. Seeing these things on a daily basis, I would not doubt that you have a bad inner. It’s highly possible. May want to get a second opinion from another reputable shop though