Questions Regarding Combination Lathe Mills

[Trevor Dennis]

Hi guys. My first post here. My Menz Shed in Blenheim NZ is equipping a new engineering extension, and considering the Optimum K416 combination lathe mill shown in the link below. Apart from the general concern around overall rigidity, I am more concerned about the lack of lateral movement control (lathe spindle axis), which — I am assuming — has 20mm per turn of the carriage wheel, and 0.2mm per sub division. I'd be interested in people's experience with combination lathe mills and how they compare with a stand alone vertical mill?

https://www.machineryhouse.co.nz/K146

[Mike Amick]

I have had about 4 of them .. with the last one pictured below. So .. I answer your
question with a little experience.

I have to admit .. the one that you linked to doesn't look too bad. But ... will still suffer from
some of the problems inherent these machines.

I finally went with separate machines ... because ..



Rigidity as you already mentioned ..

The machine I had (below) had a decent mill table ... the one you link to ... seems pretty limited.

Having some operation set up (mill or lathe) and you need to quickly change operations to the
other. (This one was huge in my decision )

The last huge one ... was .. the work for the mill was always at the wrong height. I had short
vices, tall vices, stacking plates ... all kinds of stuff to get the work to a good place.

Seriously .. for that money .. you can get a better lathe, and a batter mill. I know NZ isn't
a treasure trove of stuff .. but .. I would be looking.

[boslab]

First off, welcome, wrt the combi machine, my opinion and only mine is there's nothing wrong with them, they are all fairly generic these days, much of a muchness, what's more important is what your planning to use it for, if small bits n BoB's, models etc it's fine, but if you want to go down the Manley man skills route you'll be changing it for a bigger lathe and a stand alone mill, or mills or lathes and mills and grinders and,......you get the idea, machines are like magnets to other machines, I'm going to bet the big problem you'll have is the availability, there's surprisingly little about even in an industrial area these days, at least affordable kit, it is better than not having anything, and can do surprisingly useful work but I'd go with as rand alone mill and lathe, I used to think lathe then mill but to be honest I'd do it the other way round(useless pun), a mill is a drill, and a boring machine and a mill, with a mill and welder you can build just about anything with thought, and off the shelf round stock!
Either way enjoy yourself, it is fun, at my age I get more fun in the shed than the bed, least that's what I told her
Mark

[BCRider]

If the scale of work you wish to do involves primarily small model stuff then fine. But it's not really a suitable machine for doing anything larger. And in fact even for smaller size model items it may well prove too small to do the jigs and fixtures that you might wish to make to make the small parts.

The cross slide table on that machine is VERY small and that means the cross slide table movement will be very limited. Again we're looking at smaller projects only.

Perhaps it would better to tell us what sort of work it is you wish to accomplish. Then we would be in a better position to suggest if this machine is adequate or not.

[J Tiers]

As that is to go into a place accessible to many, with the chance that more than one person may want to work, There is a disadvantage to the multi-machine.

First, yes, it does provide both mill and lathe without taking up a lot of room. It does have that going for it. The lathe portion is essentially a 10 x 20 machine (in inches).

However, the disadvantage is twofold.

First, just one person can use it. If the lathe is in use, the mill is not accessible to anyone else. Likewise, if the mill is in use, the lathe is obstructed. I have no idea how many are interested, but presumably several, or it would not be considered at all. That makes the one-person issue more of a problem, as we all know that "quick stuff" always takes considerably longer than expected.

Second, it is not unknown for items in such locations to have things go wrong. And, of course, if that happens, it is possible for the entire machine to be out of service, which is not true of separate machines.

My sense of the situation is that you would be as well off to obtain something equal to a "9 x 20" lathe, and a similar level "mill-drill". Pricing there I have no idea of, but from Grizzly, we can find a lathe for about $1000, and a mill for about $900. Given that a similar 3 in 1 can be had here for between about $1500 and $2000, you would likely not be spending any more, and perhaps less.

I know you have no access to this particular machinery, but as an example, here is the sort of thing I mean. Neither is top notch, but both are usable, and likely at least as good as the 3 in 1. And the mill has a 5 x 19 table, rather than the modified crosslide of the combo.

http://www.grizzly.com/products/Mill...campaign=zPage

http://www.grizzly.com/products/9-x-...campaign=zPage

[Bill Pace]

What the other fellas said ----

My good friend bought one and he absolutely hates it! He comes over to my shop quite often to borrow a REAL machine. Setting up his mill is a nightmare, the lathe is semi OK.

[Robin R]

You can also buy the same lathe and mill separately. https://www.machineryhouse.co.nz/L689# And. https://www.machineryhouse.co.nz/M649

[Paul Alciatore]

Trevor,

Welcome to the HSM board.

I have not used a combination machine unless you count the Unimat which is about a 50mm x 150mm lathe that has a vertical column and a small milling table that bolts to the cross slide. And a small table is what I see on the model that you are looking at. Depending on the work you will be doing, that can be a severs disadvantage.

Another consideration is that a lathe cross slide is not an ideal platform for a milling table. From the photos that they show, the main lathe ways look like a Vee in the front and a flat in the rear. The Vee guides the carriage and the flat in the rear provides the needed third point of support. Now, in a lathe, the cutting force is directed almost straight down toward that front way and the rear way has little load on it except for the weight of the carriage and compound and tool post. This downward force holds the carriage firmly on the front and rear way and there is little tendency for it to lift or move front to back.

I have made a milling table for my SB lathe and have milled on it. One of the problems is that when milling there are often forces in almost any direction, including to the front, to the rear, and UP. These forces can and will cause the lathe carriage to lift off the front and rear ways and then it can move to the front or the rear. Now, there are blocks below the ways to prevent the carriage from lifting very far, but they will allow it to lift for a distance of one or several tenths of a mm. What this means is you have to be careful of the direction of the forces while milling and you must take light cuts. So, milling work will take longer than it would on a milling machine of similar size, which will have dovetail ways which prevent lifting.

I am not saying you can not mill on a machine like this. But it is more limited.

If you can at all find the space for two machines, I would highly recommend going that way.

[Mike Burch]

Welcome aboard, Trevor.

Be aware that although Optimum is a German brand, the machines are still made in China.

The general consensus of opinion is that the limitations of these combination machines drive you nuts. The combo you're looking at is the smallest, and therefore the most irritating, in the range. And given that most Men's Shed denizens are at an age where reaction times are slowing a bit, the slowest lathe spindle speed of 150rpm is too fast for panic-free threading.

A further consideration (applicable to the Men's Shed environment) is that if Fred wants to turn something at the same time as Joe wants to mill something, there may be Words.

BTW, in my experience Machinery House are good guys to deal with.

[pinstripe]

Hare & Forbes has a few sales every year in Australia, I assume they do the same there. You will get about 15% off the usual prices. I think their birthday is coming up soon. You can also sign up to their mailing list and get a couple of vouchers worth $70. You can use those for the tooling.

I bought my mill there this year. No complaints. Had a problem with it, and they were out to fix it within a few hours.

I would look real hard for a used machine in this price range. You will get more for your money.

[kendall]

You can also buy the same lathe and mill separately. https://www.machineryhouse.co.nz/L689# And. https://www.machineryhouse.co.nz/M649

In many cases with that style combination machine, the bases/tables are often available alone. It's a fairly convenient way to jump in and get started with a clean upgrade later when/if you want separate machines.

[Trevor Dennis]

Wow guys. I am overwhelmed with all the advice and help. You have a great forum here. I'll try and answer some of the questions...

We currently have 35 members, about a dozen of whom are active, but most them are primarily interested in wood working. I joined the shed after learning that they were building the engineering extension, and I have discovered a few other members are also mainly interested in metal working. The bottom line is that we have no way of knowing what sort of metal working projects are going to come along.

I started my working life with a tool making apprenticeship at Ford UK, and worked 38 years at Ford's Research & Engineering facility at Dunton in Essex. I spent a lot of years making load cells that fitted between typically a suspension component and the vehicle mount, to measure loads that were later used for accelerated durability, 24/7 shake rigs. I later joined a small design team, but I always had access to a decent workshop, and I have sorely missed that since taking early retirement 12 years ago, and moving to NZ.

For myself, I have a keen interest in video and photography, and I have a number of projects planed around that from camera sliders, jib arms, lighting mounts etc. There are endless ideas that can realized with access to the right equipment, and I am sure the other guys will feel the same when they see what can be done. I have concerns about the sort of rough handling our machines might have to endure, which is another reason I am concerned about the combination lathe mill. On my first day at the shed, I found several grind wheels loaded with brass and aluminum, which would have got you shot in my old workshop!

We do a lot of community projects, and recently made a big Wendy House for one local school, and some changing room cubicals for another school. We make wooden Christmas trees for the Hospice charity shop, and are currently making new seats for the Breast Cancer lady's Dragon Boat. We get drop ins for everything from sharpening lawnmower blades, requests for welding that we will soon be able to undertake — our first purchase for the engineering extension was a nice TIG/MIG welder which will be set up as soon as we finish painting the extension.

The son of one of our members works for the company we sourced the welder from, and got us a _very_ nice price for it. We think we will get similar discounts on future purchases, including machine tools, but I wonder if we might do better looking for used equipment. You wouldn't believe some of the equipment that has been flat out gifted us in the woodworking shop. The Jointer/planer we were given last week weighed a hefty 450lb for instance, which I imagine equates to a decent machine, but I am no woodworker.

I am going to be away for the next week (I'm going to Adobe MAX in San Diego helping to teach Photoshop) but I have asked the engineering subcommittee to hold off on any decisions about the lathe / mill, and I have sent them a link to this thread. So once again, my sincere thanks for your warm welcome and both the amount and quality of your advice. I'll be sure to update you with how we get on.

Trevor Dennis
Rapaura, near Blenheim New Zealand.

[RB211]

I've used much larger combination machines, they are better than nothing. If more than one person wants to machine, you are going to need multiple lathes and mills. I highly suggest separate machines. If one person has a decent project going, the machine will basically become his own until he is done with the part(s). This isn't like woodworking where machines do not need to be dialed in for a certain setup. 20 people can use an edger, radial arm, or even a planer in a single day. A milling machine, one guy may need it for 6 hours straight.

[BCRider]

For some reason I thought this Menz Shed was a store and you just used an interesting way of saying that they were stocking this model of machine. Now I realize it's more of a commercial rental or cooperative deal.

In that case I'd suggest that separate machines are pretty much mandatory. First off it allows two machines to be used instead of only one at a time. Second is that I've yet to see ANY combo unit which did not require exceptional knowledge and skills to work around the inevitable shortcomings in such machines. Over the years the very best combo machine I've ever seen was still missing some of the basic features that I expect in separate lathes and mills. A new comer trying to learn on such a machine is going to find that much of the wise words in the excellent beginner's books were wasted because the combo machines don't have some of the features that are taken for granted on a proper dedicated lathe or mill.

And from what I'm seeing in the pictures this model isn't even one of the better combo units. So it'll be lacking in even more such basics.

If you are one of the folks involved in suggesting equipment for this metal shop keep in mind too that the machines are useless without a good range of tooling and other support parts. There's end mills to be bought and some way to sharpen them or an ongoing budget to replace them as they are damaged. There's boring heads and slitting saw holders and the boring bars and saw blades to use in them. There's dial guages, calipers and micrometers to be obtained and maintained. Angle plates, V blocks and rotary tables. And the list goes on. All in all take the cost of whatever machines you buy and then figure on that much again for a selection of all the rest of the stuff.

A lathe and mill isn't much good without a way to cut the raw stock down to size to use in the machines either. So a metal cutting bandsaw or cold cut saw or abrasive chop saw will come in handy. Frankly I'd suggest the bandsaw just because it's way less noisy. The setup would also require a couple of proper machinist style benches with very sturdy bench vises that have the jaws at the proper height for file work. And files to go with the vise of course. And then bench grinders and on and on and on......

Needless to say the list goes on and on and the amount rises quickly. All of which is to suggest that the cost for separate "medium size" lathe and mill over the cost of this rather limited combo unit would not be all that much more. Having had a smaller machine for a while and then found a 12x36 I'd have to suggest that for a lathe a 10x22" size would be a rock bottom minimum machine for such a shop. A 12x36 might well prove far more useful over all.

Perhaps start with something like the 10x22 and similar size table top mill. And see how it goes. If enough folks find that items can't be fitted and completed in such machines then perhaps add a larger pair later on but keep the small machines.

I'll end by pointing out that metal and metal working machines are not very forgiving of mistakes. Carriages can be run into chucks or drills end up going through the work pieces and into the vises and expensive end mills can be chipped almost before the machine comes up to proper speed. All this because the medium being worked with is often as hard as the machines themselves. And the cutters can't tell the difference. Are the folks that run this outfit knowledgeable on this or are they babes in the woods about metal working as well?

[Lew Hartswick]

My standard comment of any device that does more than one thing; I doesn't do any of the multiple things as well as a dedicated machine. :-)
...lew...