Steve's manuals are indeed well written. As an engineer, I was required to write countless technical manuals with complex drawings like this, and I know it is not easy. So I appreciate the time Steve puts into these. The SP14 manual allowed me to assemble my first clock ever without any issues. I can also add that it is very helpful to read sections out of the manuals for other clocks besides the one being built. The manuals are available to read without having bought the files, and they often contain helpful information pertinent to the clock you actually are building.

I asked this in my moon phase clock build thread. Spacer 7a does go under Gear 7. In Steve's answer, he said it could go either top hat up or top hat down, either way. I chose to go top hat up, against the gear.

Thanks for the feedback. Yeah, the MSDS's on these products seems to always be mysterious. Everyone I guess treats all these products as "intellectual property". I'll be interested in seeing what the new profile looks like. I was thinking that regardless of geometry, because of the layer lines in any printed gear, anything that "fills the voids" can be helpful. But maybe not, depending on how the new profile dynamics behaves at the working surface level.

That's a great price. I've been using the Geeetech brand of marble. But it's like $19 on Amazon.

Cool. Looks good. I love the marble filament. I've been using it on projects; it hides imperfections really well. And just has that solid look.

Glad to hear it's running good. The clock is stunning in all B&W. So much contrast between the frame and gears. I like it. The pictures definitely personalize the clock. Nice tribute to your loved ones.

Understand. Following along any of this without notifications will be near impossible. I logged out and logged back in, which often clears weird stuff like this, but nothing. I'll have to think about it some more.

It's a Wix thing.

No sweat. I am suddenly not receiving my notifications for some reason. I checked in with Steve to see if he know why. I have the same issue with the Reply box. When it shows up as a grey box, right-click your tab at top of the browser and reload the page. The reply box always appears for me after a reload/refresh.

On file size, I'm wondering if TurboCAD handles STL differently than Fusion. My higher quality STL's aren't that huge. Totally manageable. Ahh, that's true on free Fusion. I neglected to consider that this is a business for you, lol. I use it strictly for my hobbies, but I easily justify the cost in what it allows me to accomplish. There is no way I could do all the design, analysis, CAM, 3D printing, laser cutting, CNC, etc, etc, without it. I pay for a full seat as it is worth it to me. On another subject, I suddenly am not getting any notifications on this forum. I checked my settings, nothing changed. Any ideas?

Correct. Izz is the only one that matters since it is the MOI about the rotational axis, assuming of course you have made your arbor your Z axis in CAD. To clarify, in my analysis, I did not reduce the size of the teeth. Only the outer most ring that the teeth are riding on. So no change to the locking and impulse surfaces at all. I was going to ask you what CAD program you were using, because I notice nearly all of your curved surfaces are significantly tessellated, such that the flats are huge. This is especially troublesome I think in the ratchet. The inner surface that the paws slide on is tessellated, which is likely contributing to the jamming issue. It is most noticeable on the outer surface of the clock face, which is the largest circle. But I can even detect it on the escapement gears. I use Fusion 360, and aside from Solidworks, is in my opinion the best out there for DIYers. Super cable CAD program with CAM, Analysis, Simulation, Rendering. It does it all. You can use it for free, with some limitations, to try it out. In Fusion, the STL are exported with zero detectable tessellation on any of my curved surfaces, no matter how large. Round surfaces 3D print perfectly round. Maybe in your CAD program of choice, take a look at your STL Export settings, particularly Chordal Tolerance and Deviation and Angular Tolerance and Deviation. Here is a pretty good guide by Markforged: How to Create High Quality STL Files for 3D Prints

Hey kick, Sorry, but I didn't see a message come in from you about you reading up on creep.

Steve, thanks for continuing to improve the moon clock. She is definitely a worthy cause. Very interesting that you are working on reducing the moment of inertia (MOI) of the EW. I had gone a similar route and drew up a fairly faithful version of the original EW to see how much the MOI would be reduced by reducing the radial thickness of the outer ring part. Because as you say, MOI is function of r^2, so any reduction in mass way out there at the ring should help if one want to keep the same gear diameter. But the difference was only 16%, so I didn't pursue it any further, deciding the difference wasn't significant enough. I was hoping for more like 50% reduction in MOI. So I think you are on the right track reducing the diameter instead, since the r^2 will obviously give you way more bang for the buck. Here are the results I had for the outer ring reduction analysis I played with. I used ABS as the material since it was already in my material properties library. Close enough. So far, my clock is still ticking along nicely. So I would rather wait on trying this new design to see if time will affect my build. And if it fails with time, I can work to try and figure out where the failure is. That would probably be really good info to know.

Ah shucks. Friction somewhere is ever so slowly sucking the life out of it. How much drive weight are you currently using?

That's great. Sounds like maybe there was some minor gear/arbor binding going on due to frame twist/alignment.

I'm sure Steve will chime in as well but, the double bounce on the entry pallet occurs on my clock as well. Although it's a tiny loss of energy, I would say that is not your problem stopping the clock. The double bounce I believe is a combination of a bit to much elasticity between the pallet and the escape tooth, coupled with a bit to harsh of a drop, coupled with a low drive torque on the EW which permits the EW to reverse direction upon bounce. The exit side of my escapement doesn't bounce. Because I think the drop is a bit less harsh on that side, and the elasticity between the pallet and the tooth are on opposite faces, which affects the lock geometry and collision dynamics of the left side compared to the right. The missed beat is a major issue. That shows that there is not enough torque at that instant to drive the EW adequately during the entry of that escape tooth. But amazingly, there seems to be pretty good energy in the EW the rest of the time. Does adding just a little bit more weight, say 1/2 pound more, eliminate the missed beat? To me, it looks like something is hanging up the EW at that instant. Important question to try and find culprit; does the missed beat happen only once, at the same tooth on the EW, each rotation of the EW? Or does the missed beat occur twice during one full EW rotation? If only once during each EW rotation, then I would rule out the EW pinion, since it would drive the next gear down a bit over 4 times for each EW rotation (54/12). If it happens randomly, then the issue may be further down the going train. If it happens at the same EW tooth each time, I would first claim EW imbalance, or something else weird is going on with the EW or between the pallet and the EW at that spot.

My printer is good. I print very complex mechanical parts all of the time and never have any issues with alignment, fit, tolerance, etc. I printed 4 EW's on the moon phase project, and every one of them was imbalanced. I could not figure out the source of the imbalance, but I have some ideas. For one, I have not been using "Random" for my seam position. I use "Aligned", which puts the seam in one particular spot around the ring. It could be the accumulation of a tiny bits of extra PLA in that one spot, added up over all of the layers. Or it could just be the nature of 3D printing; minor variations in over/under extrusion during a print, etc. I will need to print an EW with "Random" and compare to rule out seam position as the culprit. As far as checking the mass balance of the EW model itself prior to printing, I could do a CG analysis on the model to see what the computer says about it (to make sure CG is on exact rotational axis in your model. But I don't have the STEP file of the EW and can't do that analysis with the STL. Your CAD program should have a mass analysis command. Fusion does it easily. Maybe check CG on EW model and report back on your findings. If you would like me to do that for you, I will need the STEP for the EW. Below is a link to a video I made when I was testing and balancing my EW. The setup shown has the pallet removed and a 0.9 lb weight hung single string. That was the minimum weight needed to have the EW stop due to the imbalance, depending on the rotational position of the EW. By iteratively reducing the weight this way, the imbalance can be made to show up and be detectable, otherwise the wheel would just spin up despite the imbalance. At minimum weight, you can also see that, once the wheel picks up a tiny bit of momentum, it is able to overcome the tiny imbalance, along with dynamic friction kicking in, and the wheel spins up. With that setup, you can see that the red side of the EW is approximately where the "heavy" side of the EW is. Watch as I slowly rotate the EW to get the imbalance to rise up and over the side of the wheel, enough such that the 0.9 lb drive weight can overcome it. Until it comes back around to the bottom, at which point, the torque on the EW is not enough to "lift" the imbalance back up and over the top. Repeat and repeat to verify. With that issue verified on the wall, I removed the EW and performed the balancing procedure. All super good after that. Clock runs like a top right now. Now, I can literally blow lightly with my breath from a foot away and cause the EW to rotate. None of the other gears need this level of attention. They have so much torque compared to any gear imbalance that it is in the noise. But for the EW, that is a whole different story. That sucker is super sensitive to reliable performance, at least on my clock it is. Link to EW tests

The way I got a feel for the static friction in my entire going train was by removing the pallet, and finding the minimum amount of weight needed to start the EW turning when released from a stand still. My moon clock, after my tuning tweaks, will start turning with less than 1 pound. The OP should try this test as well, after making sure his EW is floating on air.

Hello, I recently built the moon phase clock. Running great so far, but it's only been running for a couple weeks, so time will tell. But in any case, as Steve has said in other writings, a fly landing on the escapement wheel can stop it. That is no joke. Try this. Remove the escapement and Gear 2 (the gear one down, engaging the escapement wheel), such that the escapement wheel (EW) is on its own, free to rotate. Put the clock back together and hang it on the wall. Slowly, and softly rotate the EW about a 1/2 turn and let it go. Repeat over and over starting from different positions. Watch to see if it always preferentially rotates back to the same position. What you are looking for is imbalance in the EW. On my clock, an imbalance that amounted to 0.20 grams at the ring of the EW was enough to stop my clock. Once I balanced the wheel, that thing was off to the races. Below are a some pictures showing what I did. The first shows the super simple, dual blade balance jig I made in just minutes. Works like a charm; it is how we balanced RC model airplane and helicopter blades and rotors back in the day. The second is the amount of masking tape, stacked in small sections to get the balance right in terms of weight and location, that amounted to 0.20 grams. The location is found by waiting for the wheel to stop and settle in its preferred un-blanced orientation. The weight to be added is at the apex; very top. Once I had the required weight and position, I 3D printed a sliver of gear ring, weighed it and trimmed it to get the required weight, and then glued it at the required position on back of the EW. Like balancing a car tire. Leave the sliver a tad heavy and trim it with an Xacto after gluing it on the EW, using the balancing jig to dial it in perfectly. The last two pictures show the fix on the back of the EW where it cannot be seen. When properly balanced, the EW, while free to rotate on the clock while hanging on the wall, should be free to rotate with just the whisper of the wind, and with no preferential rotational imbalance. And I mean absolutely free to rotate. Then try again man.

Don't use any of the Share tools. Copy the URL from the address bar in your browser to your clipboard (Ctrl C). Then in the comments box on this forum, select "Add Video", and paste (Ctrl V) the URL into the URL box. Then click "Embed Video"