Adding lathe ballast to reduce vibration...

[dbhost]

I've seen a couple of these discussions, and understand the why one would want to add ballast to a lathe, particularly one with stamped steel legs like my Central Machinery #34706, or a Jet JWL 1236. But the question is where, and how to add the ballast... And why pick certain locations, high or low?

My idea is to, for the time being, while a proper cabinet is being designed and built, to simply bolt the lathe legs to a cut to size and drilled in the proper spots piece of ply, and add bags of sand or concrete (that are taking up storage space in the shop anyway), to keep the thing from jumping around. And using the space above the spreaders to mount yet another piece of ply to drill and peg for lathe tool / accessory storage.

I have seen folks recommending that the ballast be placed higher up the legs, as close to the lathe bed as possible. I am not sure I understand why....

[mudder]

The only thing that I can recommend is to attach as much ballast as you possibly can!

[RayintheUK]

My stand and cabinet are purpose built, the only place I ever considered for the ballast was immediately below the lathe bed. That said, my stand legs are vertical, so the load goes straight down and doesn't put any undue strain on the unit.

My cabinet below the ballast trough is enclosed with doors. I've seen any number of tool rests and holders mounted below the lathe, but I never would because of all the shavings and dust they collect.

If you store your tools edge down, you'll often have to scrabble about to find the one you want, once the shavings start to fly. My favored position is a wall rack above the lathe, with tools stored edge up.

Ray

[dbhost]

The wall behind the lathe is sort of out of bounds for storing any more tools, my router bit cabinets are mounted behind the lathe, and the intended final place in the garage for the lathe is by the garage door on the right as you look at the garage from the front of the house... So in or on cabinet storage is my best option...

When the shed goes up, the lathe tools are slated to be mounted to broom clips on the wall immediately behind, and above the lathe bed.

So that brings me back to the... Why mount the ballast up high? My concern is with ending up splaying the legs with too much weight. Is that a legit concern?

[Russianwolf]

I think the further away you place the ballast, the less effective it gets.

You could conceivably put the ballast and inch off the floor, but the vibration gets to travel from the bed to the ballast attachment points before it's being absorbed, so you bed is still going to jump around while the feet are staying in place.

Put it further up and vibration gets absorbed before it gets a bounce going.

My unit is solid cast iron. Bed and legs. The ballast shelf is about half way down the legs.

[dbhost]

So big important question then...

If I had to chose between mounting the ballast low, or simply building the cabinet with a ballast box up high and waiting until I finish that to add ballast, which would be the better choice?

I am honestly concerned adding a couple of hundred pounds of ballast say up by the spreaders is going to splay the legs of this thing before I am done building a cabinet for it....

Maybe I am unduly paranoid....

[Russianwolf]

the cabinet will add alot of ballast to begin with, so you will see an improvement in just building it. When you then add the extra ballast, it will improve again.

I say do it right the first time and trash the old legs.

[dbhost]

Kind of what I was thinking, but I honestly wanted to get some control of this hopping around before that is done. Big bowl blanks of the faceplate are, well... interesting... I can control it with a foot on the spreader like I said...

I guess I will try putting a bag of sand across the spreader on each side for now. 160lbs should be enough for the time being...

[gerti]

I built one for my new lathe from 2x6, leftover flooring, 2x12 for the top, and a leftover plywood cutoff for a recessed shelf. I put some garbage bags in the legs and under the top and filled them with sand, about 150lbs. The shelf is almost packed full with WW magazines, which adds a bunch more weight. I placed the shelf so there is almost no room above the top of the magazines, so they stay relatively dust free.




Have not had much time on the lathe yet, but so far so good, no vibrations worth mentioning, even with mid-sized unround stock.