New guy here, cylinder head question
Let me start by saying Hello to all. I am a professional mechanic. I am interested in buying an inexpensive mill for resurfacing cylinder heads. Any suggestions on Used machines would b appreciated.
If you are willing to take light cuts and take your time, a BP might work - but the machines I've seen are usually much larger. I see you can get LARGE R8 cutters on ebay - albeit very pricey. I'm also curious what folks opinions are on these.
6" ALUMINUM FACE SHELL MILL FOR BRIDGEPORT, HAAS, NEW | eBay
10" ALUMINUM FACE SHELL MILL R8 BRIDGEPORT, HAAS, NEW | eBay
If you are a pro, you should be using professional tools, and an inexpensive mill won't be the ticket. Buy a purpose-built head surfacer. If you need money, you can always sell your $9500 Snap-On rolling toolbox!
I have resurfaced some things on a bridgeport, before but your better off to get something that is going to be more ridgid setup. You will also need a big cutter like the ones listed above probley atleast a 8-10inch facemill. As far as the cutter above they look like a pretty good milling cutter. The last machine I was using was a cincinnati of some sort and used a NMTB 40. The millhead will also need to be tiltable or you need to make angled fixtures. The bridgeport would only be a secondary option if I could not find a bigger mill with the NMBT 40 spindle. Also make sure you don't go cheap on your head holding fixture, make a good ridge holding system.
Inexpensive is a relative term. What is your budget? Seriously, inexpensive to me may be crazy pricy to the next guy. Good machine tools and inexpensive generally aren't used in conjunction.
Generally, inexpensive, decent mills lead into discussions of machines like the Bridgeport. There are lots of them around and some good prices can be found. If you want a mill for a variety of things and intend to resurface a cylinder head once in a while, then a Bridgeport will work. Keep in mind that a Bridgeport (and the many clones) are very universal machines, but they are going to require good fixtures, some set up time, and are not going to be good choices for any kind of production / volume work in that application.
Mills like the BP do have the flexibility to do lots of other jobs though. You have to decide what makes the most sense for you. If you only resurface heads once in a while, and don't really have other work for the mill then it probably makes sense to just send the heads out and pay the guy who is set up to do them. If you want to resurface cylinder heads in any kind of volume you should really look at a more purpose built machine. If you want the mill for a variety of jobs with some resurface work mixed in then something like a BP may work Ok for you.
the anti BP sentiment here kills me sometimes.
I understand the sentiment for most of the bigger guys on here with large shops who need huge rigid machines for both volume and accuracy but to say that a guy cant use a BP to resurface a head or three every few months is just ridiculous.
the OP's username looks like it suggests motorcycle heads...
i used to do lots of 3 cylinder aluminium heads and blocks, including o-ring grooves in the cast iron sleeves, on the bridgeport with no problems.
That ad is a cheat on 2 levels.
They merely "suggest" is would fit on any 1-1/2" dia arbor, "available in R8". IOW, go ahead, send them most of a grand, put it on the arbor with wimpy R8 shank, fire it up in your BP on a CI head & see what happens. See if it comes out as smooth as the photo. Preferably not a customer's head to start with.
1-1/2" dia stub arbor in a 50 or 40 taper, ok. Better yet, use a centering plug & bolt on to the face of the NT 40 or 50 taper spindle.
Second cheat, they make a "virtue" out of extolling the aluminum. Light weight might or might not have useful qualities for tooling depending on what you are trying to do with it. Not so sure it is ideal for this app (other than you can put it on a BP and turn on the switch) Wonder how long the pockets last in CI? Maybe if you are meticulously careful and clean when changing the inserts. I know, should go without saying, but really, aluminum pockets on something that expensive...
Re "cheap" mills: does a worn out BP face flat enough over say 20" (max you can face and clear a 10" cutter at each end)? Most worn ones have saggy tables and worn in the middle, so on a cut like that the part is humped in the middle when it comes out.
My take is that you can deck heads on a BP, but not make time if this is a commercial venture. And the time you waste & the constant risk taken, is not to the customer's advantage. Lots of machines can cut a head and make it look nice. If you actually spot it on a surface plate, is the result really any better than it came in, with perhaps a little surface plate spotting & judicious draw filing work?
if you are needing to only make flat heads, manifolds, etc a platen grinder (belt surfacer) would probably be better - and extremely faster.
i have a much larger peterson model but came across and sold a kwikway (kwikway master head surfacer) like this for 400 last week.
Kwik Way Master Head Surfacer Machine for Cylinder Heads, S/N:879-1006... - Repocast.comŽ
i bought mine new in 85 for 8k and have recouped the investment many times over
I have done heads on my BP.....Not much fun but it can be done......Like on your own stuff....Damm hard to make any money on it. The saddle on a BP is not wide enough, the table will droop a bit when extended to one side or the other if the gibs are a bit loose or it has any wear on it. On a 20 inch long head the surface will have an arc in it. .002 / .003 is what you will probably see.
I used to do heads for 5hp WKA spec engines on a Bridgeport M. These were kinda fussy and had a lot of setup time in them. But the machine was very capable.
Last week I did a pair of 1965 SBC iron heads. Only took .010 off to clean them up. Set up and multiple passes took all day to get both heads done. Definitly a hobby job, not for profit. The machine is capable. But they are done right and not half assed like I've seen done by our local auto machine shop service. Twisted angled cutting from those guys.
If you are doing little heads, a B'port will be fine, Auto heads really require a better, bigger machine.-----
Unless this is a hobby.
Not to dissuade anyone but to view this from another angle, do you have the necessary tools to effectively judge your work after you mill a head? With many engines today running <1.5 mm piston to head clearance, you really need to consider not only the thickness of the head but also surface finish, valve stickout, length of pushrod vs new rocker position (pushrod engines), parallelism between centerline of cam bore and the head's combustion face (OHC engines), and several others. Considering that larger mills tend to sell for considerably less than BPorts and other home shop sized mills, if doing it right, the mill is the cheap part.
As with many things in life, many can do this job but few can do it well. Building an engine that runs is easy, but building one that runs well for thousands of miles and produces mountains of power and torque is quite another.
I do Chev V8 heads on a Holke mill with a 40 taper spindle. This is basically a Bridgeport clone but a little more ridgid. You need a good crossfeed. I cut them with a flycutter not an expensive shell mill as shown on E Bay. I made up fairly simple holding fixtures that allow me to manipulate the head. ---Trevor
By "inexpensive" I meant I wasn't looking to spend $50k. Don't know how much or what brand would be a good choice. Thankfully I'm old enough that my "$9500 Snap-on box" was actually only like $3000.
Seriously though, any machine suggestions would be great. It would actually be for automotive heads. Cast iron and Alum as a hobby.
start checking craigs list daily as they are around your area (so cal right?)
look for any good used, preferably American, machine tool and do a search here to find info.
Just about every machine manufacturer has been covered in great detail at one point or another on this forum.
just steer clear of any 'mill drill' thing with a round column and most things of questionable asian origins.
rules here prohibit certain machine discussion, mostly limited to the hobby grade stuff, so check the rules before you ask make specific questions.
good luck and happy hunting!
Head size and material would be nice to know.
I have used a 12 inch face mill on a B-port, put only one insert in it and cut heads. It will work and is stiffer than a long arm fly-cutter.
When cutting heads you intentionally tilt the head slightly so that the trailing edge of the cutter does not touch.
This is true even in 50 hp production machines. Much effort goes into this alignment.
Many used B-ports are worn in the middle as for some reason people don't move the vise around to distribute the wear.
You need flat travel, so a worn high hour machine may dip in the middle of your cut.
I send these poor used up babies to the scrap yard but sometimes they sell them rather than sending them to be melted.
I pity the poor guy who gets one and tries to make a 18 inch long .0005 flat part.
If it fits in the envelope you can do just about anything with a B-port, it just takes a bit longer than the big iron.
You have to love these do it all machines.
The machines most automotive shops have are wimpy little things and there is no way in heck what comes out would pass QC in a production facility.
I see no reason a good condition B-port, setup to cut heads would not do a better job.
My experience is in finishing .030-.060 off a V6 or V8 head in less than 12 seconds. I doubt you need this kind of speed.
If I were shopping for a machine to do automotive work like this, I'd look seriously at an older Cincinnati or similar horizontal mill. Massive castings (rigid), an overarm for supporting an arbor (more rigidity), a large table (support & travel for longer heads, maybe even some blocks), and just about any type of slab & milling cutter you can imagine. The cutters are somewhat expensive compared to tooling for a Bridgeport, but they can be resharpened upteen times before they're spent. Add to that, you could resurface flywheels, brake disks, drums, ect. with a little ingenuity. Price-wise, they can be had for about the same price as a good knee mill. If there's a downside, it's not having a quill for drilling & tapping. Just something to think about.
I'm with many of the others on using a BP. Yep, you can do it, but it's going to take you a long time.
I'd rather have a bed mill. Much more rigid.
If I was buying new, it would be a Sharp KMA-1 or KMA-2
SHARP HEAVY DUTY BED-TYPE VERTICAL MILLS 10 HP-20 HP MODELS NEW
$50-60K! Used are out there, not much cheaper and hard to find.
SHARP KMA-2 Millers, Bed Type Used - MachineTools.com
You can pick up a K&T for little more than scrap price. The 415-S is a nice machine
KEARNEY & TRECKER 415S-15 Millers, Vertical Used - MachineTools.com
The old Milwaukee's are about the same
MILWAUKEE Millers, Vertical Used - MachineTools.com
I used to have one of these
BROWN & SHARPE #310 Dynamaster Millers, Vertical Used - MachineTools.com
The "Milwaukee" is a K&T, is a 4CH with 15HP - definitely a go getter
I just use a BP clone, R8 and about a cobbled together 10" flycutter - you won't set any speed of production records, understatement(!) - and straight 8s won't be in the vocabulary, but for the odd one here and there....which sounds like your situation, more than likely sufficient.