Lathe base feet position

[joeblow65]

I've never seen a lathe bed sag in the middle. I've seen the middle have more wear on the ways from use, but not sag under its own weight. Twist is a completely different ball of wax and 100% something that needs to be mitigated by leveling.

 

[Dabbler]

The four leveling feet on the headstock are essential for establishing the Z direction of the headstock. the bed is just along for the ride, it will curve to accommodate the stresses in Z linearly and in Z as twist. By converting the headstock to 2 leveling feet, the Z direction is unconstrained. Good luck with your accuracy.

 

[jwmay]

I've never seen a lathe bed sag in the middle.

Have you seen a lot of lathes with altered support configuration? If yes, then probably it’s no big deal.
But if every lathe you ever saw was being supported as intended by manufacturer, then this might indicate that manufacturers have figured out the optimal method of support, and that changing it is adding variables you have never contended with.
I don’t care what you do. It’s just something to chew on I guess.

 

[Nesse1]

If a lathe bed could not twist or sag you wouldn't need leveling feet at at all. Suit yourself, sir.

@joeblow65 The lathe bed on my 3800 lb LeBlond lathe twists easily, as does the bed on Top Lipton's 6500 lb TOS lathe. Do what you want, but your are losing all the accuracy of your lathe. The headstock needs 4 feet for a lathe of that type and size. you are re-engineering the lathe without the benefit of drawing the force diagramme or doing an FEA.

Machinists fix this problem all the time. We make 6 pucks, usually from solid steel, to one each under each foot. It has nothing to do with strength of your casters. Strength does not equal rigidity.

If you *want* a mobile base, that is an entirely different thing. A very long discussion.

Unless I'm understanding @joeblow65 , he said that he will use four casters, and two screw feet. So his plan is to use four feet under the headstock.

 

[joeblow65]

Unless I'm understanding @joeblow65 , he said that he will use four casters, and two screw feet. So his plan is to use four feet under the headstock.

Thank you, that's exactly what I decided. which is why I asked the question on which would be best.

 

[jwmay]

You know, I sort of glossed over that word “caster” through the whole thing. I was sort of stuck on feet. My bad.

 

[Dabbler]

Unless I'm understanding @joeblow65 , he said that he will use four casters, and two screw feet. So his plan is to use four feet under the headstock.

Then I am sorry for misreading your post. If you like I will edit all my above comments.

Each of the casters will still need to be leveled. But why casters and not solid pucks? It seems expensive.

 

[matthewsx]

I agree, casters on my mill yes, lathe no.

I've had them on both and if I needed to make my lathe mobile I'd build a base that could be lifted with a pallet jack.

Also, Footmaster is not the same as Carrymaster.

Zambus knows how to make these things so they'll last. I had some cheaper ones on my lathe and was disappointed with their performance. I have these ones on my mill (bought from a member here) and am very happy with them.

Adjusting the feet on the type with the rubber puck in the center is a pain when the machine is up against a wall. If you build your stand so whatever adjusters you have are accessible from the top you'll be much happier IMHO.

John