King 12 x 36 question

[Susquatch]

@Dabbler's advice above is excellent.

A good machine stand has three primary goals. Storage space is not one of them.

1. It needs to be STRONG enough to hold the weight of the machine without flexing or distorting under the forces that the machine imposes on its environment. A STRONG stand will support a military tank.

2. It needs to be RIGID enough so it can absorb and dampen the vibrations of the machine so it cuts smoothly and quietly at all speeds without resonating at any speed. A RIGID machine will quietly survive a gravel compactor. To visualize RIGID, it helps to think about a seismic mass - a mountain of granite or a concrete base the size of a house. Thankfully, there are many other ways to improve rigidity and eliminate harmonic vibrations.

3. It needs to be just FLEXIBLE enough to allow the machine to be optimally aligned on all of its axis. For a lathe, that means aligning the tailstock, removing bed bend and twist, and axially aligning the axis of the spindle to the axis of the bed.

The last goal is the hardest to do. The second is the most difficult to understand. And the first goal is the easiest to do. The first goal is also all that most machinists try to do.

Put another way, a weak stand might collapse or bend under the weight of the machine. A non rigid stand will allow the lathe to shake and vibrate which results in chatter, noise, and bad finishes. And an inflexible stand will result in unintentional tapers and non-concentric parts.

It's easy to make a strong stand.
It's hard to make a rigid stand.
It's very hard to make a strong rigid stand that is also flexible.

Of course, all three goals are heavily constrained by the design of the machine itself. All lathes can benefit from a, strong rigid stand, but not all lathes are designed so they can be aligned in use. It helps to understand the strengths and limitations of your machine BEFORE you make a stand for it.

 

[Proxule]

Like our fellow genius and fellow resident of the forums Everett, I copied his idea of making a frame around the 2 sheet metal bases and used hockey pockets to adjust the height as needed or required.
Like this!

https://www.hobby-machinist.com/data/attachments/187/187260-fdad314e80aac6aa1bb00aa278154bd3.jpg

 

[Susquatch]

I copied his idea of making a frame around the 2 sheet metal bases and used hockey pockets to adjust the height as needed or required.

I personally believe that the standard OEM style or similar homemade cabinet of double column cabinets made of heavy plate steel with 4 adjustable feet on each cabinet and either concrete mounts or vibration isolating pads is the best way to mount a mid sized hobby lathe with a 10 to 15 inch swing. There are better ways to do it, but the cost benefit isn't there for hobby usage. That is just my opinion.

 

[justin1]

Seen few YouTubers use these for machines they want to move around

 

[Former Member]

If you go to the PM site for the same lathe you can find the sheet formed cabinets and cast iron cabinets as options.

As funny as it sounds, a lot of lathe bases actual have some flex to allow straightening of the ways. The trick is to ensure the support points are stable. I have mine mounted on isolation pads bed is straight, but you can rock the lathe and it settles to back to its original position, vibrations are absorbed in feet.

I got them from KBC and they are not cheap.

 

[Susquatch]

As funny as it sounds, a lot of lathe bases actual have some flex to allow straightening of the ways.

I agree. Everything deforms under force no matter how big or how strong or how heavy. It isn't if, it's only how much.

For those lathes (like mine and Degen's) that are designed with a fixed head and bed and dual cabinets that are used for alignment, the lathe bed can be bent or bowed down in the middle by raising the far outside feet on both cabinets. By raising the inside feet on both cabinets, it can be bowed up. By raising the front feet on one cabinet and rear on the other cabinet, the bed can be twisted. By raising the left feet on the left cabinet and lowering the right feet on the left cabinet, the headstock can be pointed down. These are not big movements - only very tiny - but still when correctly executed, it is "usually" enough to properly align the lathe. It is a long interative process because one adjustment usually affects the others!

Other lathe designs differ in the methods used.

 

[mbond]

Based on your picture, I would think about x bracing in the stand.

Susquatch outlines good criteria. He uses the word flexibility for the 3rd aim, but I would use the word adjustability. You don't really want your stand to flex (as in bend or sway), but you do want to be able to adjust it (screws, clamps, shims etc.) so as to be more level, square etc.

 

[Susquatch]

Susquatch outlines good criteria. He uses the word flexibility for the 3rd aim, but I would use the word adjustability. You don't really want your stand to flex (as in bend or sway), but you do want to be able to adjust it (screws, clamps, shims etc.) so as to be more level, square etc.

I agree with your revision. Adjustability is a better word.

 

[historicalarms]

One thing i havent seen anybody address in this thread But I think is appropriate to do so is flood coolant drainaige from a dead level flat chip tray. . When a chip tray is attached to a lathe bed directly they are basicaly level with each other and flood drainage is not as quick as it could be if one corner of the chip tray is lower than anywhere else (with a hose drain installed in this corner.
I purposely installed shims under the high end of my chip tray ( In my case the i wanted the high end under the headstock and low end under the tailstock end) under the tray under the headstock and an equal amount of shims between the tailstock end and the chip tray. I ended up with a level lathe but a 1" drain drop to the chip tray.....just something you might want to consider before a final leveling is done.

 

[Proxule]

One thing i havent seen anybody address in this thread But I think is appropriate to do so is flood coolant drainaige from a dead level flat chip tray. . When a chip tray is attached to a lathe bed directly they are basicaly level with each other and flood drainage is not as quick as it could be if one corner of the chip tray is lower than anywhere else (with a hose drain installed in this corner.
I purposely installed shims under the high end of my chip tray ( In my case the i wanted the high end under the headstock and low end under the tailstock end) under the tray under the headstock and an equal amount of shims between the tailstock end and the chip tray. I ended up with a level lathe but a 1" drain drop to the chip tray.....just something you might want to consider before a final leveling is done.

And to expand on this logic. Spray coolant. Less mess ( flooding ) but more setup and or equipment.

 

[Susquatch]

I purposely installed shims under the high end of my chip tray ( In my case the i wanted the high end under the headstock and low end under the tailstock end) under the tray under the headstock and an equal amount of shims between the tailstock end and the chip tray.

Good point.

And yet another reason to hate that misleading term we all use - "leveling a lathe". We don't really care if it is really level. We really only want it aligned which may or may not be level.

I prefer to say "align the lathe" instead of "level the lathe". Leveling is so misleading.