milling flathead heads (How?)

I have a 36LB block all rebuilt for my old 34 3 W that I am building highboy style. I am putting on some 36 ford alum heads. The machine shop I took them to(who rebuilds race engines for the circle track guys) wants to know what a good fixture would look like or a suggestion on how to hang-em in the machine. Anyone out there with a idea? By the way I am putting on a early tattersfield 2 carb manifold also. Thanks.

 

Huh?? he cant figure that out himself?? Mabey i'm a little lost from being around aerospace machining too long, but it seems easy to me

 

Huh?? x2.

 

Ya might wanna take 'em somewhere else.......

 

x3 run away fast!

 

Flip them over level and bolt them to the milling table. Cut them with with a fly cutter.

 

Gotta agree with all of the above. Take your work elsewhere. Take his machinery with you, he won't miss it and does not deserve it.

 

Maybe he just doesnt want to machine them for you, so he is playing dumb.

 

I'm not an engine machine shop -- so excuse the question

How are you going to bolt them to anything (using the 21 studs) and still mill the sealing/deck surface? What type of fixture would you use? Seems to me they need some sort of vice that picks up the sides? Unless they have a means to bolt through the plug holes?

 

Believe me these guys are good. The problem he said was tring to get the heads affixed to the plate. because there are no bolt holes at a right angle to the surface that needs to be milled. we thought you could bolt them thru the spark plug holes but you do need to have a stand off to square the surface to the cutter. I was hopeing someone had a picture or a simple idea to hold the head. Thanks for the comments so far, any others want to weigh in? Thanks

 

Actually there is no hope for those guys.
That is one of the easiest jobs there is.

 

Get both of your cylinder heads under your arm and run like hell.

 

http://www.jalopyjournal.com/forum/showthread.php?t=261262&highlight=flathead+machining

No pics though.

 

I also suggest that you RUN away from there.

I mill flathead heads all the time. Ford 8-9N tractors and automotive heads. Old 40's Caddy V-8's and old six cylinders. Just a basic part of the business.

Most good surfacing machines use an adjustable stand system mounted to a base. The heads set on large pegs and are not fastened into the machine. The down force of the cutter head and plain old gravity keeps the part secure to the machine.

I wouldn't try to cut that large surface with a conventional fly cutter (unless you have a large horsepower machine, very slow feed and a 12" flycutter). Most modern machines use multiple CBN or carbide cutters on at least an 11-12" cutter wheel or a grinding stone system.

 

......... Or, you could sand those flat within .0003 of an inch like I've done in the past with other cylinder heads...

 

When it comes to machine work on a flathead you really need to find a flathead guy.
My friend that dose mine has a lot of dedicated tooling he has made over the years to do this stuff correctly.
A bunch of it is the same as other engines but some of its not.

 

Now that makes total sense! This is a standard machine shop service that has been going on for decades -- I've probably walked by the machines countless times (just never ran one) or paid much attention. I was just curious how they held large flat heads -- think 'Straight 8'! Whenever I've seen a large fly-cutting surface machine running . . . I stay the hell away from it!

 

I couldn't agree more -- if you do this work for a living and don't know the procedure or how to run the equipment, I'd sure as hell not have my parts in your shop!

 

Thanks for all the comments both good and bad. The have the best machine made for heads. Like all over heads which they do probobly 98 percent of the time, the heads are fastened on the exhaust or the intake bolt holes and then leveled to the cutter. What kind of fixture(picture please) would ypu use for a v8 flathead which has no holes to moint to and the back surface(the top of the head is (sloped) uneven to set on to a plate or mount. Thanks

 

Great stuff Bob !

It took TWELVE totally useless and unhelpful posts, before someone here actually knew how to do this.

 

I totally disagree that the posts above are useless.
Let's say a mechanic want to road test my car so he can diagnose the problem.. He gets in and asks, "What's this other brake pedal for"?
I would rip him out of the car and get the hell away from him. But, maybe it'd be better to teach him how to drive a manual shift?
I don't think so!!

 

"It is so simple a caveman can do it".

 

The original poster asked how to do it.

Twelve subsequent posts did not answer that question, because none of them knew. That is not helping.

 

The people that answered have probably surfaced more heads and blocks than anyone on the whole website.
We have helped the original poster by saving him time any money.
Once he finds a shop that can do the job right, he can stand and watch how it is done.
Now what part of this don't you understand?

 

The people that answered, clearly did not know how it was done.

Take it somewhere else is not an answer to "how do you do it".

 

To Barnfind08. As stated in my first post. Throw the roll-over fixture away and set the head on 3 or 4 pegs from the base of the machine. Some places use a three pin system I prefer four. With four standing adjustable pegs. I can mill a flat anything. I do exhaust/intake manifolds all the time as well as the mentioned flathead stuff. Anything up to 38" long. This is BASIC stuff. Been doing since the sixties on more than a half dozen different machines.

Shop machine is changable from CBN to stone. Home machine (ancient wet Lempco-pre Kwik-way). Is a 12" stone. I prefer the wet stone for surface, but it stinks (literally) and cutters are faster.

 

I have never liked using stones on a good machine, the abrasive gets into the slides and stays there. But stones sure can give a fine finish.

 

Many a time Ive walked in to the shop as the apprentice was planeing a head .Overhead /Flathead/Gimme head ,whatever and its arotating stone like a potters wheel ,with an adjustable table height . Get the picture?

 

Thank you gentlemen for shedding some light on how this is done. It is not something I think I will ever do on my mill but once the question was asked, I was kinda thinking it was more complicated than it actually is. Using 'gravitons' to hold something in position for machining is NOT the way it is taught.

Also, I like Warpspeed's post, the BS answers do not make for good reading and tend to be counter to the idea of a forum where we share info about really old , and let's be honest, obsolete technology (usually).

Prime example being all of the great tech stuff posted here on the HAMB that I think we have all learned from. Probably better for us who want to learn something to not read any of that stuff. We should just run away quickly with our stuff and go straight out and find somebody who knows how to do it instead, it'll be more fun that way.

We wouldn't want anybody learning how things are done, especially on 'state of the art' 55 year old motors now would we?

 

The one that puzzled me was "because there are no bolt holes at a right angle to the surface that needs to be milled..."
Huh?? There are still 21 of them, aren't there?? That is absolutely baffling and ultimately terrifying. I won't go so far as to suggest he was planning to mill the wrong side, but that is sure puzzling to me. If he was referring to the tops of the holes, they too are 90 to the side needing milling...they aren't in a single plane, but that is pretty much true of most engines.
Any actual issues would have to do with the dome clearance, assuming these are the heads for domed pistons and not the flattops.