Choose a new lathe..........

[hughie]

I have used steel fabricated lathes in the past and have found that there is a harmonic that sets up when turning at certain speeds. It becomes a vibration that shows up in the final piece.

Paul, Interesting comment I have built a few all welded lathes and have not come up against this problem.
I don't doubt your experience just wondering what I am doing that causes me to avoid the problem.
Now you've got me thinking will problem spend all week end trying to get the it to happen

 

[Evon Barvinchack]

Choose a new lath

I've got a 50+year old 12" Walker Turner that I have used for several years. Over all it is a pretty good MT#1 lathe but very restrictive in size of bowls. Soooo, last month I bit the bullet and bought a Jet 1640/2hp 3 phase motor.
So far I'm very happy w/it. I wanted the new a mustard monster but for another $ 1,100.00 I said no. (Woodcraft had a special 2 day on line sale). I'll spend the other thousand on toys, chucks, tools, etc.

 

[hughie]

Paul, here you go

 

[MichaelMouse]

Paul, Interesting comment I have built a few all welded lathes and have not come up against this problem.
I don't doubt your experience just wondering what I am doing that causes me to avoid the problem.
Now you've got me thinking will problem spend all week end trying to get the it to happen

You have to have deflection to develop vibration. If you are rigid in the extreme, there is no subassembly deflection. The whole thing swings, or nothing swings.

 

[hughie]

You have to have deflection to develop vibration. If you are rigid in the extreme, there is no subassembly deflection. The whole thing swings, or nothing swings.

[/QUOTE]

True, but I note that Paul turns spindles and I only bowls. So it some extent the spindle may actually be a generator of vibration.

Also within the design of all my lathes using square hollows sections, there is internal bracing vertically on the headstock to increase stiffness.

I am unaware what brand of lathe Paul has used in the past and so cannot really comment on the design.But some commercial models are filled with concrete to prevent the problem of vibration/deflection etc arising.

I only build mine because I can and I had much of the material on hand for free. In doing so, I build them for specific requirements. ie The one pictured is primarily for finishing bowls bottoms etc. Its regularly fitted with a large Longworth Chuck of over 2' in diameter. This allows me to have more than one bowl on the go at once.Also removes the need to change chucks etc often....more time for turning

 

[Joe Gorman]

I can now answer this question. I brought my brand new 3520b home and set it up yesterday. I just bought my last lathe and am absolutely over the moon with this guy... I love everything but the paint job... not crazy about the mustard.

I just had my shop built and am in the process of moving in so it is going to be a little while before I get some serious time on it; I have to build shelves and storage cabinets and move everything from the dungeon I was in before. Any way if I had my choice, I decided a Powermatic would be the way to go... so I did go that way.

 

[Odie]

I can now answer this question. I brought my brand new 3520b home and set it up yesterday. I just bought my last lathe and am absolutely over the moon with this guy... I love everything but the paint job... not crazy about the mustard.

I just had my shop built and am in the process of moving in so it is going to be a little while before I get some serious time on it; I have to build shelves and storage cabinets and move everything from the dungeon I was in before. Any way if I had my choice, I decided a Powermatic would be the way to go... so I did go that way.

Joe.......from what I've heard from others who own the 3520b Powermatic, it sounds like a very good lathe. I've only seen them in pictures.....but, they do look good.

I believe the 20" swing is about perfect.....well, speaking for myself, anyway.

Let us know how things go for you in the new shop......

ooc

 

[robo hippy]

I think part of the problem with the harmonic vibrations comes from tubes used for the lathe body. I have noticed it on the Oneway lathes, and on my Robust. The tube resonates, and is a sound chamber as well. No resonating while the lathe spins, but apply the tool, and there is some noise. As far as being caused by flexing, I don't know. No more flexing on my Robust than there was on my PM.
robo hippy