Seasonal Expansion and a Tight Drawer
Article - January 1, 2011
Well, vacation is nearly over and I can no longer resist the Shop Siren’s song. With the Winter Guild Build approaching quickly, its hard to focus on anything else! But before jumping into a the main course, I like to enjoy a few woodworking appetizers to make sure my brain and hands are in the right place. I have a few small things that I’ve been putting off for a while and I can easily knock those out before starting the Wall Hanging Cabinet. One of which actually has to do with a previous Guild Build project, The Shaker Table.
This traditional Shaker table was made from curly maple and will be a year old in March. It currently has the esteemed job of holding my comic books. And yes, I have a dedicated chair for comic book reading. These are the things DINKS do!! Despite the fact that the drawer had plenty of clearance when it was built, I am now experiencing some binding.
In Arizona, we don’t experience huge humidity swings and most times its just plain DRY! But wood is wood and expansion and contraction still happen. The best we can do to prepare for this when building is to consider the time of year, current humidity levels, and then crunch some numbers in a calculator to predict the maximum amount of expansion and contraction. Despite my best estimations, my drawer is experiencing some problems. When viewed from the front, you can see how much tighter the drawer is at the top than it is at the bottom.
Upon further inspection, its pretty clear that nature shouldn’t take all the blame here. Part of my drawer design relied on wooden runners. And instead of making these runners flush with the bottom rail of the opening, I raised them up ever so slightly so that the drawer wouldn’t rub and I’d have a good shot at creating a nice even gap around the perimeter of the drawer. The problem is that I raised mine just a bit too high. So when the drawer expanded and the runners themselves expanded, any clearance at the top was completely consumed and I ended up with a binding drawer. So next time, I’ll have to be more careful about how much I let that runner sit proud of the bottom rail.
Now I suspect that most folks would start removing stock from the drawer itself. That would certainly work in this case but its not the ideal fix. After examining the action of the drawer closely, I also noticed that when fully pushed in, there was a slight gap between the drawer bottom and the left rail. Yet on the right side (pictured right), things were air tight. So I determined the best course of action would be to carefully remove a small amount of stock from the right runner. Ultimately, I don’t want the gap around the drawer to be any bigger than necessary and removing stock from the drawer itself would make the gap larger. I would rather try to take the existing drawer and lower it slighty so that the gap is more evenly distributed between the top and bottom.
So how do you remove material on a runner? ANY WAY YOU CAN! Removing the top would have certainly made things easier, but I didn’t think I needed to go that far. So instead I opted for a few minutes of careful scraping followed by a light 180 grit sanding. The drawer wasn’t in that bad of shape so I didn’t have to remove all that much material.
The end result is a smooth-operating drawer with a more consistent gap all around. I’ll give the runner a nice light coat of varnish, sand with 600 grit, and then apply some wax. Its probably a good time to re-apply some wax to the entire drawer anyway, just for good measure.
This exercise is a great reminder of how small errors can bite you in the butt in the long run. At the time of installation, I knew my runners were at least 1/32″ too high. But I honestly didn’t think it would be a problem. Several days of rain and a cold front later, I was obviously wrong. But when you build pieces for yourself, you have the advantage of being able to tweak them as needed and you can take chances that you might not take when working for a client. This also bring up a good point about door and drawer clearances. While we all aim for that true “piston-fit”, in most cases its just not practical. If the drawer is made from solid wood and you build it so that it fits perfectly snug, at some point in the season it will either be loose or just plain stuck! So even when you are at the point that you can skillfully create a drawer with an even 1/64″ gap all the way around, you probably shouldn’t!