# Follow up, camber extendable table with the rack and pinion

In my last question of camber I was in the dark.
Through WW.SE I got good answers, now I know what it is, and why it's needed in extendable tables.

Now my question: is it necessary to put camber on the slide of an extendable table to compensate for eventual sagging when the table is extended to its utmost?

• Are you referring to camber on the slide, or camber on the table top itself? Dec 24 '15 at 4:34
• Could you please explain to me both? Thanks Dec 24 '15 at 8:18
• Someone added the tag warp. I thinking that's a mistake. Because my question wasn't on wood that's warping. It was asked about camber that helps to correct a problem of sagging, when the table is extended. Dec 27 '15 at 0:15
• @Nachmen That was me. I wanted to add some more tag context. I know it wasnt the best one.... closest to what I could think of.
– Matt
Dec 27 '15 at 2:47
• Please provide quotes that you have read, links that you've looked at, diagrams that you have seen, and any other context that gives us a clue where you saw the word "camber" in the first place. Jan 3 '16 at 2:18

## 1 Answer

Table slides are those pieces of wood that join the two halves of a table and support the leaves. The bigger the opening the more pieces necessary for each slide (Normally two slides per table, each made of two to several pieces of wood that mate in dovetail slots and rails.) The slide set shown here employs rack and pinion mechanisms to assure that the slides move equal distances when the table is pulled apart.

Any table with leaves is going to sag.

The problem to be solved is how to minimize the sag or how to make the table top level while the slides are sagging. One way to achieve this would be slip well placed shims between the bottom of leaves and the sliders such that the entire table top becomes level. Obviously, this is impractical.

Enter camber.

In this solution the slots in the sliders are slightly angled so that as the two halves of the table are pulled apart the center rises, negating the sag and creating a sort of stepped camber. I think that I have heard of the slots and rails being slight curved, also, but that sound exceedingly tricky.

The need for camber depends on your tolerance for sagging. If I were making such a table, cambered slides would be near the top of my list for desired features.

If you are going to make a table with leaves you are likely to be well-advised to look at the commercially available slides (Google "wood table slides".) They are available with and without camber.

The above discussion applies to four legged tables. It is interesting to note that camber is also applied to pedestal tables where the natural sag occurs at the ends and camber is introduced in the slides so that as the table halves are separated the center goes down.

• In this platform we're not allowed to thank so I'm not. Can you please show me by diagram or image how it looks in real. Thanks. Jan 9 '16 at 18:34
• How do I calculate how much I need to camber the slides is there a formula or I need to build the table and see how much the extended table sags? Jan 13 '16 at 10:30
• I have not been able to find anything on internet about it. There is certainly much trial and error which would be based on how tightly the slides fit one another. the number of pieces per slide and probably least importantly the wood used. Partly in response to your question that was put on hold, I would suggest that you buy pre-constructed slides. Jan 13 '16 at 17:15
• The problem is I live in Antwerp Belgium, I looked all over the internet. You could buy it in the U.S. In Belgium I don't find nothing. Jan 13 '16 at 17:39
• This link (siso.dk/pdf/Table%20Slides%20&%20Accessories.pdf) to a Danish manufacturer has mainly metal table slides, but on page 12 displays wooden slides. Jan 14 '16 at 2:43