Proper Fitting Lids - Too Loose, Too Tight or Just Right is the Question?

[Joseph Lang]

I’ve been a part time woodworker for 30+ yrs (hobby mostly) and only started wood turning in July 2011, so a newbie I am.

My question relates to what is considered a proper fitting lid on a turned box?

As I started turning some simple boxes my lids were slightly tight or snug which some have referred to as a vacuum fit. Slight pressure and the lid seats in place and remains on even if turned upside down. To remove, simply place one hand on the box and the second removes the lid with only slight upward pressure.

I think we all can relate to the joy of finishing your first few successful turnings and running off to show friends and family what you’ve created.

Well the small lidded box shapes (roughly 2-1/2" d x 3" h), maple burl grain patterns and overall finish were a big hit with all. However, most said they did not like the lids where you have to use more than one hand to lift it off. Could I make them looser, they asked? They did all agree that depending on the actual use of the piece having a slightly tighter (no spill) lid would be acceptable at times.

Of course wood moves and the fit will change slightly as the environmental conditions change. This causes the initial snug fit to become slightly tighter at times and brings into concerns if the piece will truly stand the test of time. When the fit becomes slightly looser you can run into the condition where a person picks up the piece by the lid which remains only partially seated and in some cases allows the box to fall away at a given point of the lifting process.

So back to my original question, what is considered a proper fitting lid? I’d like to even expand the question to cover if "Selling to Consumers" versus if entering into a "Judged Event" which I have plans to eventual do both?

Your comments, opinions and sharing of knowledge are greatly appreciated.

Thanks in advance.........JL

 

[Jim Rinde]

Joseph: The ultimate fit is considered to be a three second drop. That is grab the lid and lift it, the bottom should drop off in three seconds.

 

[MichaelMouse]

What's it for? If you're making a box that sits on the table and holds mints, the top should come off easily. If you're holding gold dust - tight. The "pop" fit or 3 second silliness are really just showing off, sort of like cutting a bowl so thin it practically bends. Supposed to show skill, but drop it once and it'll follow Murphy and slam on the endgrain and explode. Or let the heat from the old maids burn your leg if you're trying to eat popcorn.

You want tight - thread them.

 

[hockenbery]

If you are making it for show and tell at the local woodturning club it should "Pop" when you open it.

If you are making it to sell the lid should lift off without moving the bottom so that it can be opened with one hand.

There are of course some specialty boxes when a tight fit is required like those where the lid is presented horizontally


Turn safe
Al

 

[john lucas]

I try to envision the final use. Although I love to make the 3 second drop lids they suck when your selling boxes. People pick them up often by the lid and then the bottom falls off and hits the ground. Embarrassing for you and the customer.
For small boxes and things like pill boxes I make the lid either stay on by air pressure or snap fit. Larger boxes have loose fitting lids so when they pick them up by the lid it comes off and leaves the bottom.
The best solution, screw fit lids. OK not the best for all things of course because it does require 2 hands and must be small enough that wood movement won't mess with the threads. The problem I have since I make quite a few boxes is how to mark them so the customers know they are threaded. I usually have a separate area for my screw thread boxes with a label that says so. They really enjoy playing with these.

 

[robo hippy]

This is a kind of question where the right answer depends on who is buying it. For an ornamental piece, you want some thing looser. I have watched people over the years picking up my boxes. If the lid is at all snug, they tend to put it back on the table without opening it. If the lid just falls off, pretty much the same thing. So, some where inbetween. I have never heard of the 3 second rule, but do remember a 'flutter' box which had at least a 1/2 inch tenon/male piece that was fairly loose, sides exactly parallel, and pick it up by the lid, and the bottom would wiggle off. Interesting concept, and maybe more practical as long as your wood is straight grained. Anything with a finial should come off easily as people tend to try to remove the lid by the finial. I do not like the pop fit unless the tenon is short, say 1/8 inch or so, otherwise the fit is too tight if the wood moves.

robo hippy

 

[KellyDunn]

Here in Hawaii if you do a snap lid at a demo and bring it out to my place the lids swells so tight I cant get it off at all. The guys doing demos want to show off and make tight fitting lids. And folks doing boxes for other turners do the same. Box collectors I am not sure they care. I think its the total project. I dont make piles of boxes but I make one handed lids. If I want to get a swollen top off I have to put it in a kiln. If it comes off I then sand a bit of relief for the lid. But I think most buyers would be pretty upset if the lid swoll shut.

 

[odie]

Here in Hawaii if you do a snap lid at a demo and bring it out to my place the lids swells so tight I cant get it off at all. The guys doing demos want to show off and make tight fitting lids. And folks doing boxes for other turners do the same. Box collectors I am not sure they care. I think its the total project. I dont make piles of boxes but I make one handed lids. If I want to get a swollen top off I have to put it in a kiln. If it comes off I then sand a bit of relief for the lid. But I think most buyers would be pretty upset if the lid swoll shut.

I think Kelly makes an important point, here.........

I've always been impressed, by the vacuum fitting lid......but, the only people who care about that, are other turners. It's been my conclusion that nearly everyone who actually might, or does buy one, wants the convenience of opening the box with one hand. There might be a few examples to the contrary, but most buyers don't look at turnings with the same appreciation as we turners would.

ooc