Good lathe bench top material to damp vibration?

I have one of these lathes:
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that I'm pretty happy with. On heavier cuts and parting I get vibration
and I was wondering if an improvement to the stand might help. I have
the lathe sitting on of these:
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Since this bench is only bolted-together sheet metal, it can really get
buzzing sometimes. Now that my TIG welding has progressed a bit, I was
thinking I could build a bench from 1.5" square tubing, but I was
wondering what would be best for a top. A steel plate would be cool but
I have to be able to lift a 2 ft x 4 ft piece so I think that's out for
anything thicker than 1/4". It also would not be cheap. Then I was
thinking that 3/4" MDF bolted to a steel tubing frame might be "deader"
than a 1/4" plate and may be better for damping. Any ideas out there?
Reply to
lens42
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First off, you should be very concerned about chatter during cuts. I highly recommend a rear toolpost with the capability of holding a cutoff tool upside down. On a small light lathe like yours this will really help. Google this grouop on rear cutoff and you'll find a lot of information. I made one from a kit
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and it really helped on parting operations on my 9" South Bend.
I used 1/2" steel plate for the top of my lathe stand. Your point is valid about a large sheet being prohibitive in cost and weight, so I just used a raised pedestal for the headstock and another for the tailstock. Here are the plans:
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This lathe stand is very rigid indeed. I am certain that when vibration does occur during a cut, that the stand does not play a role.
Grant Erwin
Reply to
Grant Erwin
I don't think any top plate thinner than about 1/2" inch would help much when the lathe is bolted in the center with no other supports. The 1/2" would weigh about 320 pounds. I'd suggest using a 4' long chunk of 10" or 12" 'C' hot rolled channel. It would be a nice fit under the lathe, raise it up a couple inches, add a LOT of rigidity. Weight could be anything from 60 to 120 pounds depending on what you could find at your local steelyard in the 2nds and shorts pile.
snipped-for-privacy@gmail.com wrote:
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Reply to
RoyJ
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That's a 9" lathe. For my 12" Clausing, I used a three-bay (two bays plus one single) Sears Craftsman workbench. Also just bolted together sheet metal...totally inadequate. The rear panel is 3/4" plywood. Internally, top, bottom, and sides, braced with 1.5" angle iron. Bolted to the top is 1/4" thick steel plate with 3" skirts for stiffening. On top of that is 1" flakeboard. No vibration problems. For my son's 9" South Bend, a really heavy, home-built wooden workbench with 4x4 Legs and numerous 2x4 internally, 3/4" plywood back. 3/8" steel top, with 3/4" flakeboard on top of that. A "bolted-together sheet metal" bench is fine if you use it a convenient place to which you bolt some really sturdy supports. The "flakeboard" top for my Clausing is actually a cheap kitchen counter formica top. In addition to the front lip, and more important, it has that nice little backsplash. This makes cleanup a lot easier and was a convenient place to mount a full-lenght, full height back splash and swarf catcher.
Boris
Reply to
Boris Beizer
I made mine with 2 X 4's bolted together with carriage bolts and braced with an ungodly amount of the same. Works fine with my S B 9X 22. Walt
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Reply to
E. Walter Le Roy
If you use 2x4's, glue them up with the 4" sides together. My main workbench is 3" thick, 9' long. You can pound anywhere on it, you won't even know where the legs are to stiffen it.
E. Walter Le Roy wrote:
Reply to
RoyJ
Find an old butcherblock counter top/workbench top. Or bolts some 2x4s together.
Or simply get a nic chuck of I-beam or C-beam
Gunner
"Deep in her heart, every moslem woman yearns to show us her tits" John Griffin
Reply to
Gunner
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When I made a bench to carry a Boxford ME10.(pretty similar to a small Southbend) I reasoned that the bench top should, as nearly as possible, have the same expansion coefficient AND the same thermal time constant as the lathe bed.
With this in mind I made a sturdy wooden bench topped with three mighty box section steel girders laid side by side and welded together. This assembly was comparable in both weight and torsional stiffness to the Boxford bed.
While this achieved the original aim I hit an unexpected problem - extreme sensitivity of the hold down bolt adjustment. Because the welded benchtop was so torsionally stiff, a fractional thou movement of the hold down bolts resulted in more than a thou taper turn which made adjustment pretty fiddly. With patience I got a good result and the setup has remained nicely stable over several years.
On reflection I realise that the heavy stiff bench top is the wrong way to go.
There is more than meets the eye in the comparitively flimsy sheet metal stands supplied by lathe manufacturers.Because the sheet metal top is torsionally so much less rigid than the lathe bed a relatively coarse hold down bolt adjustment results in a usefully fine bed twist adjustment. The thermal time constant mismatch is of little importance because the resultant bed twist is a result of the spring force of the deflected metal top and this is comparatively temperature insensitive.
Jim
Reply to
pentagrid
I should have mentioned that you need to be very carefull shiming the mahine to a sturdy base or you will get the problems you report. On the other hand, once it's done right, the machine should hold tolerances better on heavy cuts.
snipped-for-privacy@yahoo.com wrote:
Reply to
RoyJ
My Kerry lathe notes in its manual that the lathe bed fixing bolts are not to be done up tight but just nipped up as the lathe bed is bedded on a structural adhesive, the bolts are just they for lifting and to prevent movement. Similarly when a mate fitted his boxford and later "Little john" lathe to their bases, the lathe bed was placed on a thin skim of body filler which was allowed to cure and the fixing bolts added after.
RoyJ wrote:
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Reply to
David Billington

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