Rockers, how to figure them

[Bill Huber]

I am almost finished with 2 little doll cradles for the grand daughters. I think I lucked out and got the rockers cut just right, they rock very nice.

Now the wife is thinking a set of rocking chairs would be nice but how do you calculate the rockers.

With the cradles I used SketchUp and draw one and didn't like the look and just kept doing this until I had one I liked the looks of but on the chairs I am just not sure I can do that they won't be just an arc like the cradles were.

Is there a formula or something to set the rocker length and arc? I just am not sure where to start on drawing them out.


160787

[Quinn McCarthy]

Bill,

Those are some great looking cradles. I made 2 just like then from maple and purple heart. I was working from a picture in a catalog and just tried to get something close. The rockers look like yours do. When I glued up each end I did a little testing to see how stable it was and make sure it didn't tip over. I did the same thing on a kid size rocker I built. There I made a test piece with MDF to see if the rocker fell backward. Seamed to work fine. I have never seen a formula for rocker setup.

Hope that helps.

Quinn

[Bill Huber]

Bill,

Those are some great looking cradles. I made 2 just like then from maple and purple heart. I was working from a picture in a catalog and just tried to get something close. The rockers look like yours do. When I glued up each end I did a little testing to see how stable it was and make sure it didn't tip over. I did the same thing on a kid size rocker I built. There I made a test piece with MDF to see if the rocker fell backward. Seamed to work fine. I have never seen a formula for rocker setup.

Hope that helps.

Quinn

So you just kind of do what looks good and then test it?

I made MDF templates and tried them, the first one I just didn't like, looked to high then made the next. I guess I could just do the same but it seems there should be a way to get a better start at it.

[Dennis Putnam]

I haven't made one but from what I've been told by those that have is that the only issue is the height from the floor of the ends when in the rest position. If either the front or back are too high or too low the rocker will feel as if it is tipping over. FWIW, they told me the rule of thumb is 1 1/2" in the front and 2" in the back.

[Bill Dieckman]

In doing a little rocker research of late, the general rocker setup I've found is a 42" radius curve. If you want/need to get into figuring out the absolutely best radius for your completely custom-fit (non-generic) rocker, this (http://rockingchairforum.com/2010/05/31/rocking-chair-radiuses-as-easy-as-pi/) might be of use (Hal Taylor article)