Cold Saw/V1 Design Rationale

Conceptual Parameters

• Baseplate

• 2 Fixed Blocks (mounted to baseplate by XXX, 2 shaft holes, 1 threaded rod hole)

• 1 Moving Nut Block (rides on 2 shafts, driven by a threaded rod that moves a nut welded to the block)

• 2 Shafts (radially held on the Fixed Blocks, axially held by 2 shaft couplings on the outsides of the Fixed Blocks)

• 1 Threaded Rod (radially held on the Fixed Blocks, axially held by 2 shaft couplings on the outsides of the Fixed Blocks, drives a nut welded to the Moving Block)

• 1 Clamp Handle (welded to the Threaded Rod)

Block to Baseplate Mounting

• Permanent mounting methods include welding.

• Modular mounting methods include:

Bolt into countersinked baseplate hole into block hole into nut.

Screw into countersinked baseplate hole into tapped block hole.

Screw into block hole into tapped baseplate hole.

Clamp Threaded Rod and Shafts Positioning

• The initial design branch split is whether the mount holes for the Shafts and Threaded Rod are propagated along a common centerline or not.

• Common centerline positioning provides the highest possible power transfer that can be attained through the 2 shaft 1 threaded rod system- because disjointed positioning can cause friction and bend-related force vectors not along the clamping axis of motion.

However, because the workpiece must be clamped above the centerline clamp system, bending can still occur.

• So the real design issue is which mounting style minimizes the bending forces. For the disjointed mounting style, because the shafts must not take up the clamping volume, they must always practically be below the workpiece like the Threaded Rod. The Threaded Rod has to be low anyway to allow space for the blade to bottom out on; the blade must descend at the Threaded Rod for maximum clamp rigidity during operation.

The optimal design equalizes the drive force of the Threaded Rod and the reaction force of the workpiece such that no bending forces occur and the shafts act like a carefully balanced seesaw. Hence the shafts should be somewhere between the Threaded Rod and the workpiece.