Mantel Clock design considerations

Posted: Wed Jan 06, 2010 8:58 pm     Post subject: Mantel Clock design considerations

I am planning to build a mantel clock with chiimes for a friend of mine. I've never built a clock before nor looked at any mantel clock plans. Are there design considerations I should make before I draw up the designs? For example:

Should the movement be mounted on a sound board (like a piano's) or possibly suspended on it's own frame? Since the movement I chose is mounted to the inside of the dial board, should the dial board be isolated from the rest of the case?

Should the clock case contain air space or empty volume to amplify or accent the sound?

Should there be slits or holes along the back/sides/bottom to allow the sound to escape the case.

Any additional information you can provide would be greatly appreacited.

Thanks you, Bob

Posted: Thu Jan 07, 2010 3:46 am     Post subject:

You will want to buy the movement and dial first, and then fit it to the case. For the most part most clock cases are solid, without addl holes for sound, some of the antique european clocks had fretwork with a fabric on the sides.

I would first decide on the clock style you wish to build, and then look for pictures of similiar ones. You might also want to consider buying plans.

John Nelson has a couple good books on clock case making.

http://www.amazon.com/Complete-Guide-Making-Wooden-Clocks/dp/1565232089

Posted: Thu Jan 07, 2010 2:29 pm     Post subject:

I agree with amrad. You may wish to look at specific design styles or consider plans to work from. The nice thing about plans is that you can make some alterations to suit your own personal tastes (the plans would serve as an example to work from). If you choose not to go with plans, make certain you have the movement and dial on hand to refer to (and design your case around those items).

In regard to case construction, I would be happy to share some info in regard to accommodating a quartz movement. Generally the movement will be mounted to a dial board (which will typically be 1/4" thick plywood - but can also be solid wood). Refer to the maximum dial thickness for the quartz movement (this is usually a minimum of 1/4" for chiming movements, but is available in longer lengths for thicker dial board applications). Keep in mind that longer shaft lengths can also be spaced back with a spacer block that you would fabricate. It should not be necessary to isolate the dial board from the rest of the case assembly. Air space would not be required, just enough space to accommodate the movement (with a little extra cushion to spare).

Because the quartz movement is self contained in its own plastic casing, the backside of the case assembly could be left open if you desire. If you wish to add a case back panel, there are two things you will want to consider: 1.) The back should be easily removable - to allow access to the battery and time set knob of the movement, and 2.) Drilling some sound holes through the back (ex: Qty 3 - 1" diameter thru holes) will allow the sound to be more audible. Many quartz chiming movements can become dampened when enclosed in a case assembly with a solid backing (or backing without sound holes).

Posted: Fri Jan 08, 2010 1:01 am     Post subject:

Thank you both for the advice. I have decided to go with a mechanical movement - the Front-Mounted Westminster Mechanical Movement to be precise. I have ordered the movement and a dial face so will base the case size off from the specs.

I'll take a look at the plans and see if I can garner any good design ideas from them or maybe purchase one.

With a mechanical movement, would it still be wise to make the back panel removeable for easier access to the movement for periodic maintenance? And obviously the front should open so that the clock can be wound.

Thanks again, Bob

Posted: Fri Jan 08, 2010 3:32 am     Post subject:

yes the back needs to be removable, via screws, or a door.

Posted: Fri Jan 08, 2010 2:28 pm     Post subject:

Sound holes may not be necessary in the back panel with a mechanical movement. If you do implement sound holes (or slot openings) for the mechanical movement, you will want to cover the opening of these slots/holes on the inside of the back panel with grill cloth. This will help keep dust out of the case and movement (dust, over time, can inhibit the operation of the movement).

Posted: Fri Jan 08, 2010 4:25 pm     Post subject:

Again, thank you both.

I'll most likely experiment and try a solid back and a back with sound holes to hear the difference.

Thanks, Bob