Newbie- 8" Face mill on a series 1 bridgeport

[wrechin2]

I am new to the machining world and I have a series 1 Bridgeport with a 1hp motor. I am looking to use a 8" adaptive technologies face mill that weighs 22lbs. Will this machine work ok with this cutter? Is this a ok cutter to use? Not trying to dump a ton of money into a cutter. I will only be cutting aluminium outboard engine parts with it and not that often. They are not solid and are basicly 1/4 ridges as you can see from the pic. It is 6.5 wide. Or can I make multiple passes with a smaller face mill and get basicly the same result? Granted the table and head are set up correctly. Thanks to all that reply.

[Donkey Hotey]

If you're just truing up the surface, that should work (very light cuts). If you're finishing rough castings (deeper cuts) it's going to be a whole different ball game.

I'll tell you that it's the biggest cutter I'll have ever heard of being installed in a Bridgeport Series 1. Heck, I only use a 3.25" facing mill on my Haas CNC (20 hp spindle with a gearbox). Using a fly-cutter on my manual mill, I've only ever swung maybe a 4" diameter. Eight inches is a bunch.

[Andre' B]

I made up a large fly cutter for use in an R8 spindle one time. It was made from 3 disks cut from 3/4 MFD and glued together, a 3/4 shaft epoxied into a center hole and single cutter bit epoxied into a hole near the outer edge.
Worked fine for facing off some wood blocks and I think it would have done a light cut on Al. For the cost (almost nothing) it would be worth trying.

[wrechin2]

THanks for the replys!

What if I made one out of aluminium? Would .500 be thick enough or would 1.00 or 1.500 be good? I have some .500 plate (could recould loctite/bolt together)and a R8 to JT2 adapter that I could drill and tap to mount it to. I seen one on YOUTUBE and that is where I got the ideal. Basicly like a large solid flycutter. Ususally it is .050 that are shaved off them. I don't care if it is done in multiple passes. Would a smaller cutter work? Would just a 3/8 carbide blank ground down work ok. Like I said I am NEW to machining. I got this to do work on blocks for High perfomance on outboard. Like this stuff. It is working out great so far. Saves alot of time but still have to go in a polish to where is like glass and blend by hand. I have only Had it for 3 weeks and it was basicly FREE!!! TOOLS INCLUDED!! Just had to lubricate it.

[wrechin2]

Here is a pic of the mill and the tooling. I did not include the hold downs or the vice in the pics.

[vlmarshall]

The facemills we use on the Haas machines at work are only 3, 4, and 5-inch diameter, and that 5" is a big chunk of steel. I wouldn't try an 8" facemill in a Bridgeport, myself.

I have used a flycutter that was a .750 rod welded to the middle of a bar, with square holes broached in either end for turning tools. It works well enough, and seems quite balanced.

[Geof]

Why not set it up and try it?

A facemill has multiple cutters a flycutter only one, maybe two cutters. IF all the cutting tips are 'perfectly' aligned you can use a much faster feed but still get a good finish. Facemills are heavy and rigid so the cutting tips are less prone to chatter, flycutters can be like spinning tuning forks and from this difference alone you can sometimes get a better finish will a face mill.

Whether you try the facemill or use some other cutter if it is large enough to cover the full width of the part do the cut with the centerline of the cutter travelling along the center of the long dimension of the part. This way the cutters are, more or less, travelling along the cross ribs. This will probably give a better finish than taking passes across the part with the cutters hitting the ribs at a right angle.

[Kevin Taylor]

Big is ok just turn it slow I have a home made facemill made out of a flywheel and the end of a small inport crankshaft about 10" od with eight adjustible cuters with replacable inserts It's heavy to handel but work's great but if i was to do another one I would use a shell mill holder with a slab of aluminum and a couple of insert cartrig's they allow anjustment in Z and R wich leaves a great finish . My head and block surfaser has a 12.5" cuter head with eight tri cuter's It has a small amount of tilt built into it to keep the tool from scratching on the back side .004" in the 12.5" dia seem's like what I remember
use wd40 or pledg furniture spray to keep the chip's from sticking to the tool

Good luck Kevin

[wrechin2]

I have not bought it yet. If it is not good on the machine to swing 22lbs of steel I will not get it. Would just be wasted money. Guess I will just make a multiple layer flycutter with 2 or 3 bits and use it on some of the old scrap that I have and see how it does. It is more or less a aluminium face mill more than a flycutter I guess. Thanks guy for your info and advice. I will build it and see how it does and let you all know. Thanks once again.

[John_B]

wrenchin2,
The problem you want to avoid with that 22 lb. toolholder is resonance created by the cutting action. With the slop in the quill, dovetails, etc. that is present on a Bridgeport knee-mill type machine you will not get a good clean cut, more than likely you'll get chatter due to the resonance getting exagerated in the hunk of steel cutter body and the inability of the machine to dampen this effect.
A young guy I know that inherited his machines from his dad has a cutter that was home built using brazed carbide lathe blanks for the cutter, and the holder from 1-1/4" aluminum disc (I think the size was convenient for his dad - he was a die maker and had material laying around). He just made a disc to mount on a shellmill R8 holder, cut 2 closed pockets out for the cutters to go into parralel to the spindle and clamp set-screws. It is over 7" in diameter and works real well.
We keep it set for one cutter to "rough" .005" above the other that is finishing. The minimum depth of cut we can use and get a good finish is .010" at about 1800 - 2000 rpm going at 20 IPM feedrate. For us this is cheap and effective. I've used it on my CNC as well and it cuts real real nice flat blocks.
Your results may vary - no warranty or guaranty implied. Use proper safety precautions and such as well.
Rgds, John

[mc-motorsports]

You might find this useful. Just do it, done every day. 1hp is a little small though, wouldn't make a daily habit of it.

YouTube - Cylinder head re surface skim Bridgeport milling machine fly cutter

YouTube - Cylinder head re surface skim Bridgeport milling machine fly cutter

[wrechin2]

What is Z and R???? Would making it accept square inserts or would using carbide square stock ground be ok? Thanks for the info!