My back is in mediocre shape, and being moderately tall I have been raising many of the tools and benches in my shop to make them more comfortable to work at. I would like to raise up my lathe about 5 to 6 inches, and have been thinking about how to do it. I'd really appreciate some advice on the best way.
The lathe is a Trens SN40, and it weighs around 4200 lbs. There are two pedestals: the one under the headstock is drilled at the base for 4 retaining bolts, and adjacent to each hole is a threaded hole with a leveling bolt in it. The pedestal at the tailstock end is drilled at the base for 2 retaining bolts, and 2 adjacent leveling bolts. Both pedestals are cast iron, and they both have an integral flange about 3 inches wide at the bottom contacting the floor.
The floor itself is a poured slab approximately 4 inches thick.
I have three alternative plans, and am hoping someone out there has a much better way:
1) I have some I-beam with a 1/2" thick web: I could cut 4 pieces and put two under the long edges of the headstock pedestal and two under the long edges of the tailstock pedestal. I'd bolt the lathe pedestals to the beam, and bolt (or bolt and grout) the beams to the concrete floor.2) I also have some 5" square tubing with 1/2" wall. Cut and bolt essentially the same as the I-beams above. This would clearly be stiffer than the I-beam, but might make the lathe very loud since the tubing would act as resonators. I could pour concrete into the finished tubes, or fill them with that formadehyde-based expanding foam-in-a-can they sell at the Big Box.
3) I'm also considering cleaning and roughening the concrete under the pedestals, building 2 pedestal-sized forms, and pouring concrete 6 inches high. If anyone likes this plan, I'd appreciate advice on how far out from the pedestals to go with the concrete.The design goals are: Safe, Rigid, and Quiet. OK, OK, "Cheap". :-)
Thanks for thinking about the problem; I'm really looking forward to hearing new ideas!
Dave