What material to use

[Don Morris]

I'm finishing up on making a cherry wall hanging clock from plans from Klockit.com. The back is 17 1/2" X10 3/4" and is inset 1/4" deep. What would you use for the back panel?


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[Kevin Bourque]

A poplar panel would look nice

[Sam Murdoch]

If you intend to use solid wood why not cherry to match? This would be my choice. It won't show from the face will it? What thickness? Are you concerned about wood movement? Otherwise MDF or another 1/4" sheet good material.

[Jim Matthews]

If not something ship-lapped, I would be concerned about the panel deforming the long side walls.

My suggestion, cherry veneer plywood.
That large panel, against the wall will have condensation, humidity and temperature differentials
every time the heat or cooling systems are engaged in your house.

[Don Morris]

Cherry veneer plywood is the consensus of several others. Quality 1/4" cherry plywood is $$$ but that's what I get for using nice wood to begin with. Thanks all for confirming what I kind of thought of but wondered if I was going overboard. Easier now to justify shelling out the $$$ for the good stuff.

Don M

[Mel Fulks]

I don't think plywood is right for it regardless of species . A more traditional approach would be the poplar or white pine. Especially if it is the only reason for buying a whole plywood sheet!

[Sam Murdoch]

This kit did not come with the material for the back? I agree with Mel that plywood is not warranted unless you have some on hand - "Especially if it is the only reason for buying a whole plywood sheet!". A solid wood back 1/4" or 3/16" thick x 10- 3/4" wide will not be a problem as regards wood movement. Certainly cherry is no less stable than pine or poplar and will look so much better. Leave 1/16" clearance on either side - prefinsh the back panel, all edges and faces - then tack into the rabbet at the top and bottom in the center with a small brad with perhaps a few other pins around the perimeter as you might see used to hold a mirror or a painting in its frame. There are certainly ways to design a thicker panel and frame back that can be let into the 1/4" rabbet that would completely dispense with any wood movement issues.

HOWEVER, the loose end here is that you describe this as a "cherry wall hanging clock". I wonder how they (the KlockKit folks) expect you to hang an 18" tall x 11" wide clock off the wall with a back let into a 1/4" rabbet. This to me suggests that the back needs to be securely fastened to the carcass with screws or glue. So forget everything I wrote about a solid wood back unless you rework the design or they have detailed a hanging bracket that supports off the side walls .

[Don Morris]

The back is indeed secured to the frame with screws. Klockit's design places a small round hole drilled through the back panel a couple inches from the top of the panel through which some sort of wall hook is placed to hang the clock. The panel must be removable to have access to the clock mechanism and to change settings. I see now I should have mentioned that the mechanism changing requires the back to have an access hole in it about 3 1/2" inches in diameter behind the clock face. I think that might impact the integrity of a solid wood back. But it's interesting to note that several people feel a solid piece that size wouldn't be a warp hazard if handled right. I do like the idea of a solid piece for esthetics.

[Prashun Patel]

I think there's a case to be made for plywood here. It makes for a stable back. You can use birch ply from HD (you'll only need to buy a 2x4 sheet). You can dye it to match the cherry, but personally I'd leave it white and just topcoat it.

[Art Mann]

I would also recommend plywood. I wish you lived a little closer. I have a piece of 1/4 cherry that would do nicely. The rest of it was used for the back of a curio cabinet. I would give it to you.

[Don Morris]

Yes the case for cherry plywood is clear. I've called around and nobody has any small pieces of furniture grade 1/4" ply. Shelling out $60.00 for a 4 x 8 sheet when all you need is such a small amount hurts. But after all this work, to put a junk piece of wood or fiberboard on it also would hurt. Guess I'll just have to bite the bullet and spring for the $$$. Have to come up with plans for the rest to justify having it. Thanks to all for their input. Lots of good ideas, teaching points and food for thought. It's one of those solutions where I'll be happy with the result, just not the cost.