am I turning to big

[alex carey]

I was reading up on lathes and how much they are capable of turning.

I use a GI maxi lathe 25-200
http://www.general.ca/pagemach/machines/25200a.html

With this lathe what are my capabilities? I have turned a few things in the 50 pound range. Can I go bigger than this or are the bearing already at their limit? The 3/4 motor has trouble but still seems to do alright.

Alex

[Reed Gray]

It is made for turning small things, and 50 lbs is maxing it out. You can turn a few things that size, but if you turn a lot of them, you will wear out your lathe. More power and more weight are needed for a lot of heavy turning.
robo hippy

[alex carey]

weight isn't really a problem. Here is a picture of my lathe. Recently I made an anchor to the ground on the outboard side. I am turning large out of balance stuff without a problem.




Without the anchor, starting this at 300 will make it dance quite a bit but with the anchor it doesn't budge. I actually roughed this around 450 if i recall correctly.



Which parts am I going to wear out and can they be easily replaced if they do?

Alex

[Don Eddard]

Which parts am I going to wear out...?

From the looks of the pics, your bearings, your tool rest, your banjo, and potentially your face when the next bowl decides to blow.

...and can they be easily replaced if they do?

Maybe, yes, yes, and no.

Just because a Honda Civic can tow a loaded horse trailer doesn't make it a wise practice.

[Gary Max]

Remember you are going to be the first person to know that you have overloaded your lathe.
It's time to buy a bigger lathe.
Adding weight or bolting the lathe to the floor is not a safe answer.

[Steve Schlumpf]

Alex - the fact that you are asking the question tells me that you already know you are pushing this lathe. My lathe weighs 420 lbs all by itself and then I added 7 bags of concrete for additional ballast to help eliminate vibration when roughing out large blanks. The blank you show in the last photo - I would have used the tailstock the entire time roughing out the outside and for as long as practical when hollowing out the inside. Plus, the speed would have been down to 250 to 300 until the outside was smoothed out a little and the piece was a little more balanced.

I can appreciate wanting to turn larger pieces - but feel it is time for you to seriously start looking into larger lathes! Best of luck with that and PLEASE think safety when turning anything this large!

[Gordon Seto]

I think you are pushing the limit of this lathe to it is not designed for. It has a 1" spindle and the integrity of the lathe of this size. The tool post is the mini lathe class. Anchoring it is not a safe solution. It is going to break at its weakest link, when it breaks. You don't want to find it out when the 50# chuck rolling off the lathe at high speed. When something breaks, you will be thrown off balance as well. It will limit your chance of stepping aside.
Swivel head is good for something big but not thick, like platters. When big and heavy is what you do most, I think upgrading to a larger lathe is safer and more enjoyable.

[Dusty Fuller]

And I would hesitate to turn 50lbs. But then again, I don't have anything of that size. I make sure everything (no matter how small) is as balanced as I can get it before I even turn the lathe on, but that's just a habit that I learned on my old craftsman. The lathe will do some work though, its a trooper and I really like it. Its no giant mustard, but I don't have room or money for one of those. Yet. I'd try trimming those heavy blanks a little bit more, start out a little smaller. Less wear on the equipment.

[Jeff Nicol]

What was the wood that you turned that weighed 50lbs? The one on the lathe may weigh 12-15lbs. A 50lb piece of oak is quite large! If what you have on the lathe is as big as you have done then do what Steve said and make all the roughing and inside the bowl turning with the tailstock in place. With it between centers the load on the spindle is equalized and lessened. The weight is not what makes the lathe jump around it is the out of round blank.

A 10oz. chunk can give you 28 stitches, 50lbs is a killer!

Turn save,

Jeff

[Paul Engle]

Alex I would have to agree, 10% gross weight of the lathe for spindle limit is a safe bet( if the lathe weighs 400#'s , then 40#'s max weight of the blank). You will/may wear out the spindle brgs if the unbalanced weight exceds the makers ( bearing ) thrust and radial loading. Better off with bigger lathe, with bigger bearing, bigger spindle ( 1 1/2" - 7 )bigger foot print, and closer to 800 lbs total gross weight = 80 lbs of blank.

[Pete Jordan]

Alex,
I would also agree it is too big. I have that lathe and wouldn't think of trying anything like that. I can't believe it doesn't stall all of the time. You might want to stick with the thinner stuff.

[Barry Stratton]

An Alaskan saying applies here:

There's old pilots and bold pilots but there ain't no old, bold pilots.

[Bernie Weishapl]

Wow I can't believe you would put 50 lbs. on that lathe. At that rate the bearings won't last long. As my grandmother always told me when I was doing something I shouldn't was, "you are cruising for a bruising."

[Keith Christopher]

You know just looking at that turning and I don't even have to question that is it too much for the lathe. Kinda reminds me of the old Fred Flinstone cartoon, in the beginning where they put the HUGE rack of ribs on the side of his car and it tips over. And since you're roughing the outside this will mean you're in the line of fire if it comes loose.

Be safe!!!!!! 'learn when not to turn'. One of my fears is you successfully turn it before burning up your lathe, which will mean 'I've done it before with no problems...." that is the start of all things hurty.

[Jim Kountz]

Alex I would have to agree, 10% gross weight of the lathe for spindle limit is a safe bet( if the lathe weighs 400#'s , then 40#'s max weight of the blank). You will/may wear out the spindle brgs if the unbalanced weight exceds the makers ( bearing ) thrust and radial loading. Better off with bigger lathe, with bigger bearing, bigger spindle ( 1 1/2" - 7 )bigger foot print, and closer to 800 lbs total gross weight = 80 lbs of blank.

Paul, where did you come up with these? Im not at all doubting you, its just that I have always wondered about this too and never had any real info to go on. Your formula makes good sense though and if nothing else is a great guide to live by.