Well,
I had the money now, so I ordered a complete set of precision rods and
linear bearings from here:
<
http://stores.ebay.com/VXB-Bearings-Skateboard-and-Slotcar>, under Linear
Motion Bearings in the left-hand column.
I know I could have used ordinary rods and teflon bushings from the local
hardware store, but I intend to upgrade to full-CNC sometime in the future.
I chose 4 30" rods for the X and Y axis, and 2 13" rods for the Z axis; all
20mm diameter.
The pillow blocks were interesting, but I thought they were a tad short. A
pair between 2 rods would be good enough for drilling, but I feared they
would introduce play for CNC work. So I took the independant linear
bearings. I can space them futher apart thus reducing play under stress (or
so I think).
I know I could have taken 4 blocks per pair of rods, but I wasn't ready to
spend that much yet so I compromised. I can still order them later for CNC
work if the linear bearings are not up to the task, or too complicated to
get properly mounted.
Yeah yeah, I know, I'm a precision freak. :D Wait 'till you see the
finished machine, you won't say that any more.
Robert
:)
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