Rule of thumb for pairing a lathe and mill?

[Aaron_W]

The only pairing that makes sense to me is to have 2 lathes (1 small, 1 large--like 12" and 18" swing)) to go with a mill.

If your skills run to it a friend of mine made a mount for a small headstock that he could then drop on the bed just in front of the chuck, it allowed him to do the small work which the large lathe didn't have the RPM for

Hmmm, so it does sound like there a jobs small machines are better suited to than large ones. You don't often see this opinion expressed.

 

[samthedog]

I started from scratch like you and began with an Emco Maximat V10 lathe with a capacity of 10" x 25". Although the capacity was OK, the lathe was too light duty for me as you needed to sneak up on the tolerances due to the slender build of the machine at only about 120kg. I upgraded to a Colchester Chipmaster with a capacity of 11.75" x 20" that weighs 550kg with a speed range of 30 RPM - 3000 RPM.
I purchased a mill with a capacity of 13" x 8 1/2" but ran into the issue that it did not really have the features I was looking for. I changed the mill out for a Deckel FP1 with a capacity of 12" x 12 1/2".

The way I sized and matched the machines was by capacity, horse power, weight and rigidity. My lathe is 3 HP while the mill is 2 HP. The lathe is 550kg, the mill is 700kg. Both are industrial machines designed for heavy duty work. I have never needed machines with greater capacity than what I now have and I believe that the HP and rigidity is critical for projects that require both milling and turning of tough materials.

Paul.

 

[Mitch Alsup]

Obviously if you have specific jobs in mind then you can just pick machines that are sized for the needed work, but in the case of setting up a generalist shop how would you match up a lathe and mill? No cheating and say buy the biggest of each that you can find.

I had a Taig microlathe (with milling attachment) for a couple of decades before I took on a project that required a "real" lathe and a "real" mill.

For me, sizing them, I had ample space, but the structural engineer said I had to stay under 2000 pounds of floor loading per machine due to the thin slab the shop was to be on. So I ended up with a 1300 pound lathe (G4003G) and a 1100 pound mill (G0730). My machines are approximately perfect for what I am using them for. I certainly would not want anything smaller. They are big enough that one develops a healthy respect for the amount of meat they can remove from your body in a mere instant, and dress and act appropriately around them.

 

[mikey]

So back to my question, if you were starting from scratch how would you match a lathe with a mill? By size, not brand specific.

Rule of Thumb: they should be big enough to do the work that you intend to do on them. Smaller will be a disappointment and bigger is a waste of resources.

We always come back to the same conclusions when we discuss which machines to buy. Buying the "biggest machines you can find or afford" doesn't work for the guy living in a condo on the 20th floor. Buying a mini-machine set up doesn't work if you live on a farm and have to fix tractors. You have to buy machines that suit the anticipated needs of the user.

One common problem I see on the forum is that the guy asking for advice has no idea what he intends or wants to do with the machine. I know this is a hard question to answer but it has to be given some serious thought.

 

[BGHansen]

There is no rule of thumb other then purchase each machine sized for the work being done.

One may turn 6" Dia. shafting 96" long on a 20" X 100" lathe, if the only mill work required are key ways 3" long on each end a very small mill will do that part of the job.

I turn a few of these parts per year, 5" diameter 1045 steel round 92" long in a 24" X 110" lathe, offset centers are first drilled in each end then once finish turned a short key way is milled in each end. All of the milling is done on a Bridgeport 42" wide table knee mill.

The lathe work is large and the mill work is small, choose a machine that fits the work for each.
The saddles clamp on to the part, this is how it is held in the mill, the offset centers in each end need to be concentric and the key ways have a radial position with the cam.

Beautiful finish on your turning.

Bruce

 

[BGHansen]

I started with a 12x36 Atlas lathe and a Grizzly-clone Rong Fu mill/drill. Frankly, they could probably have met all of my project needs but I upgraded lathes to a Clausing 12x24", then a Grizzly 14x40" (G0709). Still have the Clausing, nice to have two lathes. I gave the Mill/Drill to my father-in-law as I upgraded to a Jet JVM-830 knee mill (gave him the Atlas lathe also). I've since upgraded mills to a 9x42" Bridgeport 2HP CNC but kept the Jet also.

In both cases I upgraded because I wanted heavier machines and space and budget allowed the upgrades. I wanted a gear-head lathe because my Clausing requires deep knee bends to slip the belt on the pulleys for speed changes. I wanted a brake on the lathe because my Clausing is sooo smooth that when I shut off the power it takes over 30 seconds to wind down (got in a very bad habit of stopping the 5-C collet chuck with my hand). I wanted a Bridgeport so I could say "I have a Bridgeport mill", not "I have a mill like a Bridgeport, but it's not a Bridgeport" if you catch my drift.

My father-in-law picked over his father-in-law's shop after the latter passed away. My father-in-law took nothing as the shop was full of what he considered junk tools. My son is going to inherit my shop, I don't want him to begrudgingly say "Wow, dad bought a lot of junk".

As others have advised above, get what you need for the projects you intend to do, then maybe go a little larger just in case. You know you're space and budget, so go as big as you can. You can always do smaller work on a large machine, but not the converse.

Bruce

 

[mikey]

I wanted a Bridgeport so I could say "I have a Bridgeport mill", not "I have a mill like a Bridgeport, but it's not a Bridgeport" if you catch my drift.

Bruce, I loved this bit of honesty! Thanks, you made my day!

 

[P. Waller]

Beautiful finish on your turning.

Bruce

Thanks.
No magic, just a good combination of tools, speeds, DOC, set up and feed rates. Anyone can do it given 10,000 hours of trial and error or just using the recommended values (-:

The material also helps a good deal.

 

[Downwindtracker2]

I have a 12x24 lathe and 9x32 mill/drill . The lathe's capacity hasn't ever been fully used, neither has the mill's capacity , but it's come closer. I wouldn't want any thing less.

 

[JPMacG]

I can only add my personal experience. I have a Craftsman (Atlas) 12x24 lathe. I have found it adequate for every job that I have attempted. On the other hand, I have an Atlas MFC horizontal mill, which I find quite limiting. I think a better choice to go with the lathe would be a Clausing 8520 knee mill or similar. It seems that used hobby lathes are plentiful and relatively inexpensive, not true of milling machines. The 8520s are rare and expensive. Old Bridgeports are common around this area of the country, but too large and heavy for most hobbyists.