2/27/16

Frame Types and Tube Bushings


Jim emails:  "I was looking at the arbors plans for the Deco and it appears that the Wheels are a tight fit on the arbors and the arbors spin within holes drilled in the frame - is this correct?
When I built the Simplicity (still ticking, btw) some of the wheels had a tube pressed in them and that assembly spun freely on its arbor.
If I am correct about the Deco Arbors, why did you go from the tube/arbor combination to a press fit with the arbors spinning in the frame holes?  Doesn't this make the front/back frame alignment critical?  Is friction an issue?"
Thanks, Jim

Clayton:  There are basically two type of clocks that I design; plate clocks (by far the most common kind of clock) and uniframe clocks.  Genesis is a true uniframe.  ALL of the wheels of the Genesis turn on stationary arbors that are pressed into the frame:
Genesis by Clayton Boyer
Deco is a true plate clock where all of the arbors turn in the plates (frames):
Deco Built by Bob Brown
 Simplicity is a combination of these two basic clock building methods:
Simplicity by Clayton Boyer

Tubes seem to turn freely on there rods on uniframe clocks, but they do not turn as freely as simple wood hole on metal arbors.  I did the experiment with the Genesis.  One Genesis I built with tube inserts (as with the Simplicity) and on the other Genesis I just drilled the hole in the wheel and set it on the arbor.  The latter took significantly less drive weight to run the clock.  If I were ever to redesign the Simplicity I would totally eliminate the brass tubes, except for spacers and where the crutch/pallet arbor goes through the frame.  A tube is needed there for alignment.  The same is true in the Toucan.

DO NOT use brass tubes for bushings in a two plate clock.  You can read LOTS about this in my blog.  Just click on the huge word "bushings" in the right hand column.  Brass bushings are one of the two fastest ways to turn your kinetic sculpture into a still-life (the other is getting finish on the tooth surfaces).

Whenever I mount the front and back plates of a two plate clock, during the alignment process I insert rods in all of the arbor holes.  And I keep twisting them to make sure that the alignment is correct as the frames are glued and screwed in place.  Fortunately if they are not exactly aligned a simple, very slight "reaming" with a hand drill to remove the friction will solve any binding problems (but I hope that won't be necessary).

Yes, friction is always an issue in any clockworks, no matter what kind.  And the more arbors your clock design has, the more wheel sets your clock design has, the more friction is created.  Check out my Radiance one wheel clock and see how little drive weight is required to run a single wheel clock:
Radiance by Clayton Boyer
 

Enjoy! Clayton

2 comments:

  1. Question on the Demo clock - do you provide information on where to get the spring drive in the plans?

    ReplyDelete
  2. Hi Roger, Lisa here. I'm 99% sure the answer is yes, but always best to email Clayton to ask directly. You can find his email link in the FAQ section on our website--best not to list it here, as it will end up on a million Spam lists. Thank you for the inquiry and for reading the blog!

    ReplyDelete

I love comments, but in order for me to have more time playing in my sawdust, I cannot respond to them here. If you have a technical question, please do not post it here, or I will have my wife answer it for me and her technical knowledge is highly suspect. For technical questions, check out the FAQ section of my website, or find my email link there. Mahalo and Aloha, Clayton