Anyone mill your own head? If so, what set up did you use, tooling and so on? PK
I've never worked with milling machines before, but still I didn't think it was hard to do - I milled my Prus head 0.100" last week, increased the compression ratio from about 5:1 to 5.8:1. See the last post in this thread: http://www.mtfca.com/discus/messages/411944/422844.html?1399254706
I used 6 M24 bolts, about 3" long, ground to equal length to support the head when upside down. M12 bolts about 6" long with washers fit fine in the T-slots in the milling table, they held the head down through the spark plug holes. An extra clamp in the water outlet finished the clamping. First I checked the levelling by going over the head with the cutter as close I could to see where it first began to cut, then checked the opposing side how much I had to move the table up to cut there too. It seemed ok, so I went ahead and milled - but just about 0.3mm or 0.012" in each cut. I could very likely have cut more in each pass, but I was a bit extra careful since it was my first time milling. This head was aluminum, much softer than cast iron, maybe I'll try one of my high heads next, they're less of a loss if anything goes wrong (got three of them)
The last cut there was only 0.1mm or 0.004" more to mill. I took very slow passes to try minimize the rough surface coming from a very old and worn cutter on my friends milling machine. Still wasn't good enough I thought, so I spent an hour sanding it smoother on a sand paper taped onto a flat glass window pane. Then I thought it was good enough to mount after filing the edges smooth and washing all the debris out. Let's see if it will hold up
Note: If milling a Prus (or Z) head the pistons will come too close or contact the squish area in the head. I found the material in the top end of my alu pistons was thick enough to mill off some 1.5mm or 0.060" right under the squish area to make sure there's enough clearance. Not needed on original heads
Milling these heads, you have to get real creative
with blocks, wedges. Hold downs thru spark plug
holes, and a lot of tramming. Other than that
nothing really special. And tripple check your
head for perfect tram. We have done a share of
exhuast manifolds with many many blocks and wedges and hold downs.
lay a straight edge to tram it so you get an
average reading. Keep the quill up and locked and
use the knee. Cutters your choice. I dont know
what you have but give it a try on a piece of test stock.
It only cost $35 to have a head milled in my area...why on earth risk ruining the head tryin to do it yourself...just my opinion.
I milled my own head once when I was a kid and didn't know any better. Now I have the barber do it.
Thanks for the replies. I do have a knee mill with a power feed table so that helps. I'm thinking of using six adjustable mini jacks positioned in the head bolt holes and clamping through the spark plug holes. Thanks for the ideas Roger and Samuel. I'll use a 3.5" five insert carbide face mill. Any more advice on this set up?
Gary, yes your right, having it done isn't that much. I get great satisfaction doing as much as possible my self. Thanks, PK.
Guess you're right Pat.
In my area it would be more like $100(+) so doing as much as possible myself makes a difference.
There is an aluminum standard for the surface of an aluminum cylinder head and you can not get to that number with a standard milling machine. This is due to the fact the cutters available are not the type needed for the proper finish.
The new and accurate cylinder head milling machines take a single pass across the surface and that gives you the proper surface and there is no possibility of uneven machine marks across the head which will cause head gasket failure.
While this is an entertaining idea, my thought is its fool hardy and a waste of time considering what a good automotive machine shop charges. Not to mention the possibility of having your head get loose and causing irreparable damage. Then you have the task of getting the cylinder head perfectly level and true to your mill head. Not knowing what brand or style of mill you would be using, most of the so called knee mills from overseas are not up to the task. The heads of these machines are substandard for accurate machine work let alone the movement of the table and ways. An accurate cylinder head surface todays costs in excess of $20,000,not to mention the tooling and cutters at $150.00 each and 6 are required for each holder
This is my humble opinion by a company owner that surfaces and recons nearly 400 aluminum cylinder heads yearly. We do have a very high end USA manufactured mill and would never consider milling our own heads.
You are 100% right Mr. Brass Car Guy.
If you don't take it in full coverage in one pass at a time, it is 100% impossible to make it the level you need.
Well, mr Brass car guy, I think you're very lucky being able to buy all the old cars you want and repair them with state of the art methods. I'm not that lucky, I'll have to make do with what I can do myself with a little help from my friends if I'm going to play with old cars at all.
The old saying about Model T folks being cheap or thrifty - mostly that's because of necessity. Those who can't afford to play with the high end stuff still can play with T's - and mostly the T's are forgiving enough to run with shade tree methods - even if they won't run as good as with a $20,000 restore job (on a $10,000 car)
The question in this thread was "anyone mill your own head" and yes, I did. Anybody else have to consider the risks and do what they consider the best for them. There are also risks of milling off too much making the deck surface of the head too thin, for a cast iron head you may try finding a canadian cast head - I've seen references there may be more meat to mill off certain years of canadian heads.
If my sanding job didn't smoothen it enough to keep the head gasket from failing, no big issue - then I'll take it to a pro miller for another .010" pass. If I've milled off to much so the head collapses, then I've learnt something more & I'll put a iron head back.
And Herm, I've learnt a lot from your threads and all the great pictures you've posted. One thing I've learnt is to say Ok, you're right
Well, Rog, at least you got that part.
On the other hand, it's a ten dollar Model T head. I have a pile if he ruins this one. I know where Pat lives and it is probably close to half a day's drive to any place where they can do this. Either Spokane or Missoula. Maybe Kalispell or possibly Polson. Not everybody in this world lives in an urban area with every service available just down the street or around the corner. Mail service in eastern Montana is now two deliveries a week in many areas. You think they cut it, don't you?? No, they upgraded it from one day a week delivery. This is the west, not New York City.
a friend of mine took the high spots off his dodge cummins motor with a file and a straight edge. i thought thats the dumbest thing i ever heard of, but... 2 years now, no leaks
Looks like we have another Royce in the wings.
It's just a Model T. A belt sander should work fine.
I milled my Z head with a large double cut body file. I trued the surface and smoothed it up with a large sheet of sand paper on my table saw top. I now have a 7.5:1 Z head and couldn't be happier. When I hold a straight edge to the surface I don't see any light. I took two and half days work, but I just wanted to see if could be done. It runs great.
Boy am I disappointed, I wanted Herm to jump in and tell me how crazy I am.
A good milling machine and sharp cutter with the head leveled using a dial indicator and I believe it wouldn't be that difficult. Especially with an adjustable speed table feed. You might consider using a quality built fly cutter. Just level with the indicator, touch off with the cutter and know ahead of time by using a Coordinate measuring machine or surface plate and indicator how much it'll take to clean the head up and that it isn't more than you should in order to have clearance for the top of the piston. If you could do a roughing then a finishing cut you will be ok but don't be afraid of using the cutting oil or better yet a good water soluble coolant. With the correct speeds and feed you should be able to make a very good and true cut. I'm not certain of the alloys in an aluminum head but some aluminum can be a little "gummy" to cut. Cast iron is a nice material to machine. Or, spend a couple days building a fixture to surface grind the head and go into production. Or best of all spend the money and have the head done in a good, competent machine shop.
And how do you suppose it was done in Model T days if it needed to be done??? They probably threw it on the iron pile and put another one on from a junk T but if they cleaned it up it wasn't done at the machine shop next door would be my guess. It's MODEL T! It has been out of production for pretty close to 100 years. During its production years and time of most popularity, probably at least 80% of the towns west of the Mississippi did not have electricity, let alone a machine shop with a head surfacing machine.
During the first few years of production and sales of the T Ford, there were virtually no parts cars. The myth that exists that there were Model T's in every fence row is just that until they had been in production for several years. There was a ready and waiting market for used Fords from the time the dealerships opened in the west. There were few parts engines available until after WWI. In eastern Montana there were not even Ford dealerships until the mid to late teens. The local repair shop was a Blacksmith shop.
In Jefferson, Texas, there was a steam powered machine shop until it burned to the ground a few years back. All over the south there were steam powered cotton gins. I had hoped to visit the machine shop but it burned down before I could get there. I don't know how common they were but there certainly were machine shops around before there electricity was available.
Most of Montana was settled when the railroads came through in the late 1890's -- early 1900's. The last homesteading in Mt was in 1909 - 1912 when the Milwaukee came. Electricity was available by the 1930's along the railroads, much of the rest did not have power until the late 1950's. I well remember when power came to our neighbors when I was in High School. I'm sure there were machine shops in the bigger towns run by either electricity or steam (steam was a pain in the north, Ted, water freezes pretty hard at 40 below) but not in those little homestead towns 50 or a hundred miles from the railroad. My grandparents homesteaded 65 miles south of the Milwaukee railroad on Boxelder Creek south of Ekalaka in 1910. In 2010 they paved the road to Ekalaka. Carter county is almost as big as Connecticut and has about 2,000 people today. I don't think my grandfather's blacksmith shop in Elgin would have had a mill that would surface a Model T head that was leaking water.
I use my old storm vulcan head master. Does it perfect every time and can cut .035" with no problem in a single pass.
Nice setup Jeff. Next time I'm into Menards or Lowes I'll pick me up one of those.
Jeff here's it's bro.
Mine is actually raised up 2" higher than stock height so I can deck the top of a block by bolting the block straight down to the deck, without the raise it wouldn't quite clear. Nice blockmaster Randall
See, with enough money you'll be able to mill your own head and deck the block too.
To made it easy to put the head on a milling machine I made this device.