New Lathe/Mill

[customlight]

I am going to be purchasing a new lathe and mill. But in the process i came across this machine http://www.grizzly.com/products/12-x-36-Metal-Lathe-w-Milling-Head/G0492

It seems to be an ok machine as opposed to purchasing a lathe and seperate mill. What do you think, go with combo lathe/mill and save a thousand dollars. Or i can get a separate lathe and mill. Any information would be very helpful.

The separate lathe and Mill.

 

[wquiles]

I have a small lathe "and" a small mill. Definitely, get the two machines if you have the space for them. Many times now I am working on the lathe, only to need the mill to do something before going back to the lathe. Also, the mill has allowed me to work on pieces/mods for the lathe (currently using my mill to make the pieces to mount my Shumatech DRO on the lathe). Again, you will not regret having the two separate machines

 

[gadget_lover]

I've seen some nice work done with the combo units. I almost bought one myself. But they always have drawbacks.

As Will pointed out, having two machines means you can leave one set up while you do a second opperation on the other. It also means that you can work on two projects at once.

But on top of that, there is the matter of compromises. The mill in the original post has a 6 inch wide, 21 inch long table. You need room to mount the work, plus the mounting devices (rotary tables, vices, angle blocks, etc). A small table like the cross-slide of the lathe may limit the ways you can clamp your work.

My little mill (a micro) came with a table that is 5.5 inches by 9 inches long. I upgraded to a table that is 15x5.5 inches. When milling grooves, that gives me 5 inches for the rotary table, 4 inches for a tailstock and 6 inches for a light.

My big mill has an 8 x 30 inch table, and easily handles a 50 pound vice.

So if you are going to do anything big (as a 12x36 lathe would suggest) you will want a fair sized mill to go with it.

Daniel

 

[Mirage_Man]

I too would go with separate machines for the same reasons already stated. I just ordered a new lathe myself. I already have an older South Bend 10" lathe that I've been learning on. I plan to keep it at this point as a second operation machine. Most of the what we do when it comes to flashlights is done on a lathe. However there are a few things that one needs a mill for. I don't yet have a mill but it is definitely my next purchase.

I would suggest looking at the Precision Matthews lathes and mills. They are a tremendous value. HERE is what I would recommend in the 12"x36" lathe size. It's got a ton of nice features like fully enclosed gear box, foot brake, coolant system etc... They also have a nice dovetail column mill. There's a picture on the website but if you search eBay for "PM-45M" you'll find the mill with a ton of pics and specs.

 

[precisionworks]

The Grizzly G0492 is not so much a lathe-mill combo, but it certainly is a lathe-drill combo. Why? A number of reasons.

The column that supports the drill head is about what you'd see on a drill press - it is many times smaller than any milling head column I know of. Spindle travel (max drilling depth) is a tiny 2.25". Spindle to table is 9" ... subtract a vise & a cutting tool and you may have 4" of daylight left. Table size is 5" x 11" and part of that is used by the setup clamps, so max part size is very small.

go with combo lathe/mill and save a thousand dollars

For the reasons above, unless your parts can be held in the palm of your hand, you really do want a separate lathe & mill. If you don't have the room or budget for a full size knee mill (Bpt or clone) the larger mill-drills will do 90% of the work that can be done on a Bpt.

 

[gadget_lover]

Below the 'full size knee mills" there are many other classes.

In addition to the typical mill/drill (a round column with a head that goes up and down as needed) there are mill/drills with a dovetailed column. This provides more working height as the head does not lose it's position as it goes up and down.

And then there are "small" knee mills. The table goes up and down, allowing the head to be more massive and stiffer. They can be he size of a large mill-drill and about the same price.

www.grizzley.com has some of all of them.
mill-drill http://www.grizzly.com/products/2-HP-Mill-Drill/G1006
sq column mill-drill http://www.grizzly.com/products/6-x-21-Mill-Drill/G0619
Small knee mill http://www.grizzly.com/products/Vertical-Mill/G3102
Large knee mill http://www.grizzly.com/products/9-x-42-Vertical-Mill-w-Power-Feed/G9901

They all have good points.

Daniel

 

[precisionworks]

Below the 'full size knee mills" there are many other classes.

+1

My large Enco mill/drill (same as Rong Fu RF-30) was purchased in near-new condition for $1600, including Acu-Rite DRO, power table feed, and cabinet stand. That's roughly half of retail, and about half of what I would have paid for a decent Bpt (step-pulley, one-shot, chrome ways, no DRO). People will tell you about the Bpt they bought for $1000, and I've seen them at auction for about that - vintage WWII, round ram, ready for a complete rebuild.

IMO, the biggest drawbacks to the RF-30 are that the step pulleys are a PITA to switch speeds & moving the head up/down takes an extra step. That extra step is that you locate a feature on the part (center of a hole or bore is excellent, as is a corner) before moving the head - then you have to reindicate that feature after the head is moved. Adds a minute or two to the overall job time.

A knee mill is better if it fits your space & budget. But the RF-30 class machine comes awfully close in performance & it won't break the bank (purchased used).

You can even run a 1" solid carbide end mill, and mount a Kurt D675, with plenty of room for the part.