Reinforcing the mill stand

[Ira]

I added some beef to the shoptask stand to better support the lathe bed, and to raise it up a bit. Before, it seemed like the lathe bed was holding the drip tray flat, now the mill is sitting on a couple of solid pieces of 1/4" thick tube steel and the loads are carried to the legs of the stand. I used 2" x 3" tube steel. Now I need to paint it and bolt/weld it together.

Do you guys think welding is the way to go when attaching the rails to the three front back supports or will that likely warp the rails?


Shout-out to small block, thanks for the idea of enlarging a shaft by kurling, it saved a couple of things from the scrap bin.

[wildwestpat]

Hi Ira

Being a meanie I would use bolts so that the parts are reusable! Just take care that you do not distort the lathe bed when bolting it down no matter how the frame is constructed. Suggest checking the gap between all the lathe bed mounting feet and the stand using packing to make good any gaps. That said from your picture the lathe bed may twist the frame as there is no diagonal bracing in the basic structure. Those leveling screw feet need to be in good contact with a stable floor after fixing the extra bits of tube by your chosen method and then see if the lathe bed is going to be stressed after bolting up the mounting bolts.

Regards

Pat

Regards

Pat

[Ira]

Thanks Pat!

Bolts are good

What kind of packing should I use? I have some 3/16 chemical resistant rubber I got to make some chip shields. Do I just put that under the lathe feet and adjust the lathe twist by tightening/loosening the lathe bolts?

edit: OKay, I think I understand that the packing is really a solid shim material to take up the gaps (Yay/Nay)?

I'm worried about lathe twist, but I'm flying by the seat of my pants. I've read about two methods to check for twist, using a machinists level and trying to turn a perfect cylinder.

Right now I have the whole cart sitting on 4 swivel casters so I can move it around a little. I'm pretty sure this is bad, since everything talks about leveling... and I know that as the casters swivel they raise and lower I was hoping this extra steel would let me keep mobility, maybe I could use ball casters?

[wildwestpat]

Hi Ira

Got you - you need to move the lathe about. I would look for some flexible machine mounts. These are high stiffness rubber and look like a square mounting plate wth a mushroom top with a single tapped hole. Try looking on ebay or Google for antivibration mounts and you might strike lucky. By using over sized holes and rubber packing you will achieve a simlar effect but you need high stffnes rubber and I would guess 0.5 inch thick but this will depend how uneven your floor is!

Alternative would be to weld the new supports to make a strong under frame and place this on your rubber with a simple dowel arrangement i.e. to stop it falling off the stand and keep the lathe in the centre of the drip tray. Mount the subframe to the lathe taking care to pack / shim the mountings so that no stress is transffered to the bed casting and all should ne ok.

Regards

Pat