Lathe reinforcement (Denford viceory)

[Tgc]

Hello everyone!

I have a lovely Viceroy Denford bowl lathe. Lovely because it has a decent swing height, and I could afford it!
However, the nicely cast headstock is on a welded steel plate frame, which flexes terribly when you mount the nice large blanks the lathe is designed to take.

Has anyone got any tips and tricks to reinforcing a lathe, or this particular lathe? Unlike other lathes that vibrate due to lack of mass, this is a distinct flex in the structure, so it's definitely torsional stiffness that is lacking.

[Mike313]

It's hard to advise without photos at least - and I'm no expert anyway - but I did reinforce a workbench which had an angle steel frame by drilling holes in the frame and bolting on 25mm plywood at the rear and both sides. It's absolutely rigid now. Maybe you could do something similar?

[Tgc]

Apologies, I thought I had! I missed the pesky size limit, re-sized the photo, it should now work.

I was thinking something similar, but instead thought about riveting sheet steel. (Rivets transfer the load and resist vibration better than bolts).

As the photo shows, there are to gaping holes in the front, one for the door, the other an old control panel. Neither will be helping much!

[John Plater]

I have heard of others filling an enclosed base with sand.
ATB John

[Docjohn]

Hi Tgc
Could some of the flex be in you plinth? Have you considered trying a concrete slab/block?
Hope you get it sorted
Regards
John

[RichardS]

It looks like the assembly is original and therfore well teste.

I agree with the previous query are you sure it is not the wooden structure that is flexing? I would have expected a Lathe of this size and obvious weight tobe bolted down on a concrete slab probably at least 200mm thick perhaps more.

[Tgc]

Thank you for taking the time to reply! I enjoy these threads, not least because I read lots of older threads that are still full of helpful ideas.

I'm confident that the plinth is  not flexing, however, the levelling feet that I have mounted do have flex, so that needs changing.. I've also added 50kg to the plinth to see if more weight helps, alas no.

The concrete slab sounds like an excellent idea, I can't find anywhere to purchase them so I'm left with two options: pour a concrete slab, or attach the lathe to the concrete floor. I'd rather avoid the latter due to concerns over the bolts cracking the concrete due to vibration (unfounded?) but how on earth do you level a concrete slab?

*EDIT : as long as the floor isn't hideously lumpy, would a rubber sheet be enough to ensure good slab to the floor contact?

[Tgc]

As an update: the feet have been replaced (photo below). The old ones were flexing an awful lot it turns out!

General operation is much improved. Major wobbling only occurs with out of round blanks - unfortunately those are the peices I enjoy turning! Looking at the wobble on the ground level, it looks as if the lathe itself is tilting rather than flexing.

So: cheapest way of adding lots of mass in a confined space. Steel plate? Lead?

[Lazurus]

Sand oil mix in plastic (thick) bags and fill up as much as possible in the casings

[Willie]

Hi Tgc

I have a Denford the same as yours, I have it bolted directly to my workshops concrete floor, with no problems turning anything out of balance. Before I fixed it down it did give a bit of vibration.

I use it at its original height, but think if you raise it and bolt it to a good concrete base, you should be ok.

Cheers
Willie