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General Category => Tickers => Topic started by: steve323 on July 09, 2018, 11:08:18 AM



Title: 3D printed clock
Post by: steve323 on July 09, 2018, 11:08:18 AM
Here is a picture of a 3D printed clock I am working on.  The gear profiles and escapemen t were designed using Gearotic with additiona l CAD work in TurboCAD.  

It is currently running with a 5 pound weight providing a 4 day run time with 4 feet of drop.  It appears to have an accuracy within a few minutes per hour.  The finial below the pendulum allows almost 2 inches of length adjustmen t.  I just got it assembled yesterday and it runs for a couple of hours before stopping.  When it stops, the energy at the escapemen t is completel y gone, so there must be a burr on one of the gears.  The plan is to add a pulley to provide 8 days running with 10 pounds of weight.

The total print time of all the component s is somewhere around 40 hours on a Prusa MK3.  Everythin g is PLA except the shafts, weights, and a few bearings.  It has bearings for the winding drum and pendulum support.

Steve


Title: Re: 3D printed clock
Post by: Mooselake on July 13, 2018, 01:35:07 PM
Looks good!

Kirk


Title: Re: 3D printed clock
Post by: steve323 on August 09, 2018, 10:52:33 AM
Here is an update on the clock project.  I filed off the crows feet from the parts of the gears that touch the build plate and the clock runs great.  It has a lot more power and has been running continuou sly for about 3 days now.  I re-printed 2 gears to try for an 8 day run time, but it did not seem stable enough so I went back to the 4 day gear set.

The accuracy is about 1 minute per day, however it is speeding up slightly as everythin g breaks in.  I suspect that it should stabilize in a week or two.

I have a question for any clock experts.  Should the pivots be lubricate d?  They are 1/8" stainless steel shafts running in 0.005" oversized PLA holes.  This seems to provide a fairly low friction surface.  I am worried that oil would attract dust and wear out faster than if they are kept dry.

thanks
Steve


Title: Re: 3D printed clock
Post by: John T on August 09, 2018, 09:59:15 PM
Hi Steve
I donít consider myself an expert but I have some clock building experienc e with 34 clocks to my credit. The very first clock I built is all wood that is wooden gears, wooden plates, and wooden arbors. No bearings or anything like that, this clock has been ticking faithfull y since 2005.  I have never used any lubricati on of any kind.   As you noted wooden clocks do break in with time.


Title: Re: 3D printed clock
Post by: ArtF on August 10, 2018, 06:14:57 AM
Steve:

   Truly great. I know how much work went into designing and making that in a 3d printer, colour me impressed . Really nice job! .

  Generally, I try to stay away from lube in a clock, Im not a perfectio nist though, if I need it Ill add it
depending on the situation ..

Art


Title: Re: 3D printed clock
Post by: Richard Cullin on August 10, 2018, 07:31:20 AM
I have found graphite dust (locksmith stuff)  makes 3d printed sliding pieces glide smoothly and evenly,
hopefully not wearing the plastic away


Title: Re: 3D printed clock
Post by: steve323 on August 10, 2018, 09:59:32 AM
Thanks for the feedback and kind words.  I will keep it dry for now and try a dry lube if it starts to wear. 

The great thing about a 3D printed clock is that it is easy to print another frame if the pivots wear out.

Steve