Saturday, March 12, 2011

A little progress

Well, it looks like at least another two weeks on the IV.  While I'm chomping on the bit, it's going to be a little while yet before I can start ramping up the shop again.

With that in mind, let me share a little project completed during all this medical who-ha.

I've got a big, heavy, old Hozan truing stand.  It works, but its clumsy.  I've been thinking for some time about building its replacement.  Then my son asked for a truing stand for Christmas.- which further accelerated the process.

To me, a truing stand should be stiff, stable and well dampened.  It should be easy to adjust for a range of over lock-nut sizes and wheel diameters.  And, it should be easy to center the hub in the stand, so that centering the rim is not a separate process from building the wheel. A nice to have is the ability to mount a dial indicator for fine readings of true and round.

That's not a huge list of requirements, but buying a stand that meets them tends to be expensive.  For around $125, though, its possible to build such a stand using 80:20 extrusions as the foundation.

My son lives in CA, which added on further requirement: the stand has be able to be knocked down and shipped in a fixed-rate Priority Mail box.  As a consequence, on the stand I made, the cross frame is limited in size, so I had to come up with a way to mount the uprights so they would fit the cross piece and come together for a 100mm front OLD.

Note, the adjustment hand screws in the picture have brass heads and were prior to trimming to length.  These have been replaced with plastic headed hand screws, so they won't where out their threaded guide holes prematurely.  Also, not seen in the pictures are: connector plate between the two base pieces; three rubber furniture feet on which this stand sits.  These provide a tripod support (three points define a plane) which won't rock, and make sure that the stand doesn't slide around on the work surface.

Anyhow, I don't have any plans, per se, so I can't share them.  But all you really need to know is in the following pictures.  All parts not from 80:20 came from McMaster Carr, including the self-adhesive left and right hand metric scales used to align the uprights.


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