Lathe Base Plate

[LC Tikka]

Have a small lathe similar to PM1236T on factory box stands, looking at adding flat 20mm plate 1620mmx370mm 95kg under the bed feet over the stands to help reduce some vibration with mass.
The stand gap is 960mm, is it likely the plate will deflect, if so how much, any engineer here to help.
Used an online calculator, but some inputs were beyond my understanding and a bolted plate was not a scenario.
Thanks in advance.
L

 

[Dusty Stevens]

If there is no weight between the spans (legs underneath the lathe feet with a plate between) then the only sag youll have is the plates own weight. In other words if you put the plate on sawhorses itll have sag between those points naturally, then add any amount of weight on top of that plate centered on the sawhorses no more sag will be introduced. All you do is add that much more weight to the sawhorses, which in this case it will dampen vibrations and make the lathe think it has a more solid foundation. Look on a search here for a post by skeetlee where he builds a base for his grizzly heavy 10. Thats the route to take for a tabletop lathe

 

[Sleddog]

Have a small lathe similar to PM1236T on factory box stands, looking at adding flat 20mm plate 1620mmx370mm 95kg under the bed feet over the stands to help reduce some vibration with mass.
The stand gap is 960mm, is it likely the plate will deflect, if so how much, any engineer here to help.
Used an online calculator, but some inputs were beyond my understanding and a bolted plate was not a scenario.
Thanks in advance.
L

I’ve had a PM1236 Chinese made lathe for 4 years. I was just talking a few hours ago about, of all the lathes I’ve run over the past 50+ years (Monarch, LeBlond, Clausing, South Bend, etc) this is one of the best! Ive owned South Bend, Jet, Atlas & this Precision Matthews.
It cuts straight, repeatability is phenomenal & the machine Is smooth. The only thing I’ve done, is change the factory v-belt for a linked belt.
Adding a heavy plate couldn’t hurt though! Mass is good

 

[Dusty Stevens]

Heres a picture

my NEW SB HEAVY 10

Just wanted to share with you my newest toy. SB has reintroduced the Heavy 10. I haven't cut much with this machine yet, as I just completed the stand and got the chuck mounted. I think it will be a dandy though. This machine is 3phase with a built in VFD. super smooth and quiet. Enjoy the...

forum.accurateshooter.com

 

[Fast14riot]

Like Dusty said, if all load bearing columns (bed feet, stand legs, etc) are in line and you're just inserting this plate in between, there will be no loading on unsupported span and all sag would be from its own weight.

 

[LC Tikka]

Like Dusty said, if all load bearing columns (bed feet, stand legs, etc) are in line and you're just inserting this plate in between, there will be no loading on unsupported span and all sag would be from its own weight.

It is the the sag between the stands I'm interested in, it will be small. The weak link to the floor is the light wall stands, the plate will be checked and made flat.
L

 

[dnellans]

Why not pour concrete into the bases if you want to just add mass?

Assuming yours look about the same as mine, I find them very dubious for storage. Nothing ever fits quite right and it’s too small to be useful for more than a gallon jug of cutting fluid.

Each 12x12x24 column would fill with order 350lbs of concrete. If you want to add mass for the machine to get bolted to and have a factory look, it probably doesn’t get much better than that.

 

[Bamban]

On my Taiwanese built ATrump 1236 I bolted the two towers together with 2 shelves using grown ups LEGO - aka Unistruts. In the picture the contents on the bottom shelf has neen removed. These were chucks, a BP mill rotary table, and a Bison 8 inch self centering vise with swivel base. You can still see the 2 plywood pieces, in between are multiple pieces of 1 inch thick steel plates. On the top is the machinist tool box and steel stocks.

There is quite a bit of weight added between the 2 towers

 

[Stumpy1]

Bamban -do my eyes deceive me, or are those hockey pucks under each of your cabinet mounting points?

Frank

 

[Dusty Stevens]

Bamban -do my eyes deceive me, or are those hockey pucks under each of your cabinet mounting points?

Frank

They are hockey pucks. I use them for my machines too. I bet i got the only hockey pucks in arkansas

 

[Bamban]

Bamban -do my eyes deceive me, or are those hockey pucks under each of your cabinet mounting points?

Frank

They are hockey pucks. I also them for jacks on the BP mill when drilling/reaming gas ports on finished barrels.

 

[Stumpy1]

They are hockey pucks. I use them for my machines too. I bet i got the only hockey pucks in arkansas

are you guys just putting them under big washers, or something more complicated?
I assume you like them as machine mounts -details please! (and thank you!).

Frank

 

[Dusty Stevens]

are you guys just putting them under big washers, or something more complicated?
I assume you like them as machine mounts -details please! (and thank you!).

Frank

Bunch of info out there. I actually make feet with mine from carriage bolts

Lots of talk about hockey puck machine mounts...

...but little analysis. Yes, I've seen many examples of hockey puck machine mounts, and I've seen the Youtube video of the guy crushing a hockey puck with an 82,000lb hydraulic press. It would have been useful if he had used slow motion with a force gauge inset in the video! :) I'd like to...

www.hobby-machinist.com

 

[Dusty Stevens]

 

[Bamban]

are you guys just putting them under big washers, or something more complicated?
I assume you like them as machine mounts -details please! (and thank you!).

Frank

Here is how I did mine. Went to metal store and asked them to slice 1/4 inch washers from 3 inch round stock. The puck and washer drilled to accommodate a 1/4 inch bolt. The leveling bolts were faced off and drilled to allow the protruding 1/4 inch bolt to locate itself in the hole.

The faced off end of the leveling bolt rides on the 1/4 inch washer. The washer provides the area load to the puck to minimize compression.

 

[Stumpy1]

Thanks for sharing! Certainly worth thinking about.

Frank

 

[LC Tikka]

There have been many owners of small lathes who fitted a plate under the bed feet and report beneficial results in dampening cutting vibs etc, so it appears to be a worthwhile addition.

 

[wkdickinson]

A few years ago a friend passed away and his widow gave me his 1940's SB 9AX48. I read a lot about how lathes are mounted on ships and ultimately I mounted it on a 5 ft. piece of 12"X6"X3/8" retangular steel tubing, which is sits on a heavy wooden frame. The box section tubing acts like a shoe box - you can't twist it with it with the cover on.