Bearings in clocks

For the makers of various third party clock designs..
David Morrow
Old Timer
Posts: 52
Joined: Mon Dec 12, 2011 2:35 am

Bearings in clocks

Post by David Morrow »

Since I requested this clock section, I'll kick things off with one of those hotly debated topics - should I use bearings ?

I won't debate whether or not to use bearings with this post. I have made wooden clocks with no bearings, with brass tubing for bushings, and real  bearings. But, when I do use bearings, I use router bearings that I buy from Lee Valley Tools here in Canada. Normally I use 1/4" OD x 1/8" ID bearings for most arbors. For the wind arbor, I use 1/2" OD x 1/4" ID router bearings.

Brian Law and Woodentimers plans show the bearings as being mounted in the frames and the wheels / pinions being locked to the arbor with a set screw. The arbors then turn in the bearings. That OK when you can get them almost perfectly aligned and thereby avoiding any binding. It's also ok when you have zero frame sag, which also causes binding. What I do is press fit the bearings in the wheel / pinion assembly which I glue together, and and let them spin on the arbor rather than locking the gears to the arbor which turns on the bearings in the frame. I find that I have no alignment issues and, frame sag, if it occurs, becomes a non-issue.

The downside is that I have to make brass tubing spacers to keep the gears properly aligned.

I hope my description makes sense.

John T
Old Timer
Posts: 446
Joined: Tue Oct 05, 2010 9:53 am

Re: Bearings in clocks

Post by John T »

Hi,
I have made a total of 34 clocks and none of my clocks uses bearings although I have used brass bushings from time to time.  In actual fact I've found that the problems a alignment are not worth the effort of using bearings or bushings unless the wheel is turning on steel, that is not to say that if properly aligned bearing wouldn't be effective, I just find them not worth it. 

My longest running clock was put into beat in December 2005, and runs without problems other than keeping it wound.  This clock uses wooden plates, wooden gears and wooden (dowel) arbors.  It is a 30 hour movement running on 3 pounds.

John
1% inspiration 99% try, try again
User avatar
ArtF
Global Moderator
Global Moderator
Posts: 4361
Joined: Sun Sep 05, 2010 6:14 am
Contact:

Re: Bearings in clocks

Post by ArtF »

John:

Impressive. Thats a good run from pure wood IMO.

I use bearings where I can, Im not opposed to them anyway. With acrylic I find
sinking a bearing in the acrylic gear helps center it. Lasers dont cut very straight
holes, but a 15mm hole that you press a flanged bearing into makes it run very true.

  Depends on the project and medium Id suppose..

Art
doc_here_
Old Timer
Posts: 7
Joined: Fri Sep 22, 2017 1:31 am

Re: Bearings in clocks

Post by doc_here_ »

Hi folks, please understand that I am in no way an expert but recently reading through some very obscure documents I discovered that the discovery that turned clock making around way back when they were trying to make reliable and accurate ship board clocks to work out longitude was the use of Lingum vitae. This wood was able to self lubricate the bearings, is unaffected by water, salt or fresh, and its use marked a new era in clocks. I read that one of the clocks built back then has been refurbished and is still keeping good time 300 years later. I did a search and found that one of your power companies over there turned to Lingum vitae bearings a few years ago and it has been remarkable in removing all maintenance required and saved them thousands. Another search and a knife making supply company here in Aus. sent me a small block of Lingum vitae which I intend to use in small sections by inserting small blocks where my brass rods will go and hopefully will be able to get around using bearings that way. Unfortunately I then found with further searching that this wood is on the restricted list and is very hard to buy so I seem lucky to have gotten the piece that I did. Hope that this small thought is of interest, thanks for your time, Phil
David Morrow
Old Timer
Posts: 52
Joined: Mon Dec 12, 2011 2:35 am

Re: Bearings in clocks

Post by David Morrow »

I don't think I have heard of anyone in recent years getting any lignum vitae so yes, you are very lucky. Best to use it very sparingly. It would be a nice tribute to your find to use it for clock bearings.

Another thought that comes to mind when you say it is self lubricating is to use graphite plugged bronze bushings.
http://www.nationalbronze.com/News/self-lubricating-graphite-plugged-bronze-sleeve-bushings-now-available-online/




User avatar
ArtF
Global Moderator
Global Moderator
Posts: 4361
Joined: Sun Sep 05, 2010 6:14 am
Contact:

Re: Bearings in clocks

Post by ArtF »

Funny, they sell Lignum Vitae , I have a chunk on my workbench. The Navy used
to use it for the drive shaft bearings up here. It really is well known as bearing
wood and lasts a long time.. strangely, Ive never used it, I tend to steel bearings. :)

Art
User avatar
Mooselake
Old Timer
Posts: 504
Joined: Sun Dec 26, 2010 12:21 pm
Location: Mooselake Manor

Re: Bearings in clocks

Post by Mooselake »

The local (that's 100 miles east of here) exotic hardwoods place had some the last time I was in there.  Bought a 1 inch square by 12 inch piece, $5 from their web site.  No real intended purpose, but thought it might be handy to try making some bushings out of it.

Wife picked out a 2" square by 36" chunk of purpleheart.  She's not a woodworker so it might be a clue stick...

Kirk
User avatar
ArtF
Global Moderator
Global Moderator
Posts: 4361
Joined: Sun Sep 05, 2010 6:14 am
Contact:

Re: Bearings in clocks

Post by ArtF »

Theres a few types of it I notice, the real good stuff is sold by the pound, not by board foot.

Art
David Morrow
Old Timer
Posts: 52
Joined: Mon Dec 12, 2011 2:35 am

Re: Bearings in clocks

Post by David Morrow »

ArtF wrote: Funny, they sell Lignum Vitae , I have a chunk on my workbench. The Navy used
to use it for the drive shaft bearings up here. It really is well known as bearing
wood and lasts a long time.. strangely, Ive never used it, I tend to steel bearings. :)

Art
The only time I ever heard of it being used for a bearing was John Harrison when he was in the race to build the clock trying to win the British Admiralty prize in order to more accurately calculate longitude. I suspect anyone using it today is making an effort for something as traditional as possible. Here's an episode of PBS's Nova about Harrison and his clocks. Really interesting.

https://www.youtube.com/watch?v=NENPdT4LASw


doc_here_
Old Timer
Posts: 7
Joined: Fri Sep 22, 2017 1:31 am

Re: Bearings in clocks

Post by doc_here_ »

Yes, that is who and what I was referring to. An amazing tale and a shame that he died before he could collect the prize money.
There is also a great article on their modern use as bearings to be found here : http://www.hydroworld.com/articles/hr/p ... urbin.html
Ps the piece that I got here down under was 1 ?" x 1 ?" x 6" and cost me $30 and $25 shipping, sucks being here sometimes lol
Last edited by doc_here_ on Sat Sep 23, 2017 9:03 pm, edited 1 time in total.
User avatar
Mooselake
Old Timer
Posts: 504
Joined: Sun Dec 26, 2010 12:21 pm
Location: Mooselake Manor

Re: Bearings in clocks

Post by Mooselake »

doc_here_ wrote: Ps the piece that I got here down under was 1 ?" x 1 ?" x 6" and cost me $30 and $25 shipping, sucks being here sometimes lol
Just went through the Sydney airport twice, to/from NZ.  Would have brought you some (if you're close to there) if I'd known.  The sort-of local guys want $6 for the Argentine variety.

Kirk
User avatar
kit
Old Timer
Posts: 85
Joined: Sat Apr 02, 2016 3:51 am
Location: Tasmania

Re: Bearings in clocks

Post by kit »

David,
I like the idea of fixing the bearings in the wheels rather than at the ends of the arbours. I have a small lathe here so making brass locking collars with the appropriate profile to hold the wheels in place without rubbing on the outer race of the bearings will be no problem. Avoiding binding has been an issue with both the Sextus clocks I have built, but the second one, which has ball bearings on every shaft, runs with less weight than the first.

A while back I stumbled upon an article online on the use of ball bearings in clocks. I don't apear to have bookmarked it and can't find it again, but the author had made some tests of various types of bearings and came to three key conclusions:

1) Don't use the sealed type ball bearings, the rubber shrouds rub on the races.

2) Soak the bearings in mineral turpentine to remove all the lubricant. Lubricant adds drag and is not required in such a low-speed application. Corrosion is unlikely to be a problem indoors.

3) Once 1 and 2 are taken care of, ball bearings have by far the lowest friction of any of the common bearing types used in clocks.


For our Australian readers: I've used Plaig Bearings a couple of times and been happy with the speed of delivery and the price/quality of the product. They have a wide range of the weeny bearings we might want for a clock.  http://plaig.com.au/shop/

Kit
David Morrow
Old Timer
Posts: 52
Joined: Mon Dec 12, 2011 2:35 am

Re: Bearings in clocks

Post by David Morrow »

Kit, this may be the bearing article you are thinking of :
https://www.bocabearings.com/general/ball-bearings-in-clocks

Another source of bearings, especially if you are building to metric sizes, is your local hobby shop. Radio controlled cars seem to use a lot of them. And they are very small.





User avatar
kit
Old Timer
Posts: 85
Joined: Sat Apr 02, 2016 3:51 am
Location: Tasmania

Re: Bearings in clocks

Post by kit »

David,

Yes, that's it. I've now bookmarked it for future reference.

"...your local hobby shop..." Here are some notes I made for a Pommie (sorry, English) friend who didn't quite get the remoteness of where I live.

I live in Exmouth on the North West Cape of Western Australia. Resident population is about 2500. Once you leave Exmouth on the only road, your first fuel stop is 220km and the first town going South, Carnarvon, is another 150km after that. The nearest set of traffic lights are in the first town after Carnarvon, which is Geraldton, a total of 850km from here. The state capital, Perth is a total of 1300km which is the same distance as Land's End to John 'o' Groats (the two most distant places on the mainland of Great Britain), but with only the two sets of traffic lights to hold you up for the first 1250km. Perth is the only place you can fly to from here so that is the quickest place to get to and is where the nearest decent shops are to be found along with theatres, cinemas, car parking you have to pay for and all the other wonders of a modern city including hotels above 'motel' status.

On the other hand we have a fabulous climate, no traffic holdups getting to work (except the ocasional emu), no through traffic as we're on a long peninsula, wonderful beaches, many with very few people on them even in the tourist season and a fabulous fringing reef within swimming distance of the beach in places where you can snorkel out see coral, many type of fish, turtles, sharks (mostly harmless) and a variety of local and foreign maidens (mostly harmless).

I suspect there are some equaly remote places in Canada, but we don't get the snow over here  ;D

The availability of internet shopping has been a boon in Exmouth, the small Post Office is always brimming over with boxes and parcels of every shape and size.

Kit
Last edited by kit on Tue Sep 26, 2017 2:13 am, edited 1 time in total.
doc_here_
Old Timer
Posts: 7
Joined: Fri Sep 22, 2017 1:31 am

Re: Bearings in clocks

Post by doc_here_ »

Mooselake wrote:
doc_here_ wrote: Ps the piece that I got here down under was 1 ?" x 1 ?" x 6" and cost me $30 and $25 shipping, sucks being here sometimes lol
Just went through the Sydney airport twice, to/from NZ.  Would have brought you some (if you're close to there) if I'd known.  The sort-of local guys want $6 for the Argentine variety.

Kirk
Oh if only I had known Kirk, that would have been brilliant as I'm about half an hour from the airport in Oatley.
If you're ever coming back let me know and maybe we can sort something out for the next time. Thanks for the kind thought
Post Reply