Box Lid Alignment Issues

Problems with jewelry box tolerances may be related to moisture in finishes. December 27, 2008

Question
I make boxes and I have been having problems with the box lid alignment. I usually fit the hinges (quadrants) before finishing, in this sequence. Fit to the lid first, then fit one screw per leaf to the base. If there is any misalignment, I offset another screw in the direction the lid needs moved and continue until all screws are fitted. If there is still some misalignment, I sand this out. The hinges get marked so I know where each one goes. I then remove them and finish the box. The problem is when I go to refit the hinges after finishing. I follow the same procedure but find in 90% of the boxes, the lid is misaligned slightly (very little but enough to detect misalignment). I then have to plug and redrill some hole to get the lid fitting.

Forum Responses
(Cabinetmaking Forum)
From contributor J:
I have made a lot of small boxes and I am usually able to force/bend out any imperfection after everything is together. If you have to, take a clamp and force the top past where it should be. When it springs back, it should line up. If all else fails, you could put a slight chamfer on the edges of the meeting pieces, making any misalignment much less noticeable.



From the original questioner:
I have clamped it in the past, but was hoping there would be a reason for the movement, considering I got it perfect before finishing. I do put a very small chamfer, which takes the eye away from it, but the fingers pick up anything. I think what I'm worried about is that most of my boxes are commissions and I just want to give as close to perfect as possible. I was considering trying to finish the box with the hinges on, but that sounds like it would be awkward.


From contributor N:
Do you keep track of which hinge was taken off of each place on each box? The manufacturing tolerances are often pretty loose, so you shouldn't be assuming they're interchangeable after you've fit them.

Also, have you tried disassembling and then immediately reassembling them to see if the same problem occurs? That would help you narrow down the origin of the problem.




From the original questioner:
Yes, I do mark the hinges. I even went to the extent of recording the screw sequence, but still no luck. I haven't tried fitting the hinges, getting the box aligned, and removing them and refitting again (worth a try on my next box). If this is okay, then it would suggest the finish is causing movement. I did notice today that the lid seemed to have shrunk ever so slightly side to side, so it was actually smaller. The finish is Danish oil. I could try some boxes with shellac.


From contributor D:
I'm not a professional box maker, but I've done more than my share of jewelry boxes and such as gifts. I've learned to get it perfect using small butt hinges. After the box and lid are finished, I set the hinges in place with a small amount of 5-minute epoxy, which lets me get the alignment perfect. An hour later I add the screws.


From the original questioner:
Good idea - think I'll give it a go.


From contributor C:
I think you answered part of your own problem when you said you pre-fit, then finish the boxes. You didn't say what type of finish you are using, but most woods will move some amount when you finish them. The hydroscopicity of the wood means it will swell or move even putting on the sealer coat. I learned this the hard way making turned wooden boxes and also humidors several years ago. The turned boxes would sometimes elongate to an oval even when finishing with a pre-cat lacquer. This would change the final fit up as you mentioned. With the humidors the fit is absolutely critical and in some cases the box was tossed if it failed the humidification test and I couldn't adjust the top out properly. The final solution was to install the hinges, tape them off, then finish the boxes. I still would have the occasional box that would get transformed from a humidor to a jewelry box, but leaving the box assembled seemed to really help solve the problem.


From the original questioner:
Thanks. For a while I thought it was the finish, but there were so many other things it could be and finishing with the hinges on seemed awkward, but that is what I will be trying from now on.