[Kevin Sevcik]

Is there any reason you're going with a flexible beam coupling, then? Unless you're counting on the coupling as support for one end of the leadscrew*, there's a number of other coupling options available to you. You could buy a mis-matched set of Lovejoy or Oldham couplings and have your 1/4 to 8mm adapter that way. For instance, you could buy an 8mm Oldham and a 1/4" Oldham from SDP-SI for $24 each and have two of your 8mm to 1/4" couplings. Alternatively, if you want to use your Versa as support for one end of the shaft, I'd recommend finding a rigid inch-metric coupling instead of a flexible one. Or even easier, get a 1/2" output shaft for your Versa, and find a 1/4" to 1/2" coupling.

*You should only do this under light loads and low speeds. Those beam couplings are intended to be used between a rigidly mounted motor and a rigidly mounted shaft that aren't perfectly aligned. They're designed to transmit torque, not bear axial loads. If your wiper catches on anything, you're liable to permanently rip your coupling apart.