# Assembling Mitred Corners of a Box



## doitforfun (Dec 31, 2013)

I'm working on a project that I will share when I'm done. Its a lamp where the shade is box with mitred corners. I had so much trouble assembling this thing. I finally stuck it between my saw fence and a block of plywood stuck in the mitre guage slots. I'm afraid the joints may fail because I was completely unable to apply steady pressure to them with a clamp. I guess its kind of late now since I already assembled it, but if it does fail I'd like to sand off the glue and try it again. What's the best way to put this together?

Here's a picture that shows the joints and pretty much how I got it assembled.


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## bondogaposis (Dec 18, 2011)

I use band clamps for that that sort of glue up. There are a lot of specialized clamps for boxes that specifically address that very problem. Generally you need a clamp that applies pressure to all sides at once.


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## gfadvm (Jan 13, 2011)

I tape across the joints with blue tape to hold it together, then apply ratchet straps (or band clamps if you have the extra cash for them). Then measure the diagonals before setting them aside for the glue to dry to make sure they are square.


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## doitforfun (Dec 31, 2013)

Thanks. I don't have time or money for band clamps at the moment. I'm sure I could make something similar.

By the way so far it's holding although the mitres aren't as tight as I'd like. Part of that is due to some tear out at the very edge. It's red oak.


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## gfadvm (Jan 13, 2011)

Ratchet straps work as well as the band clamps just not quite as convenient to use.


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## squaretree (Feb 5, 2014)

Brian, i seen someone post a homemade bandclamp they made out of a ratchet strap.

I like the design of this lamp shade, by the way. I cant wait to see the finished product.


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## squaretree (Feb 5, 2014)

Didnt see your post there, gfadvm. Sorry for the echo


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## Airframer (Jan 19, 2013)

A rope tied around the box with a dowel or stick used to twist the rope increasing the clamp pressure works just as good and everyone has some kind of rope laying around. Once the desired pressure is reached just clamp a stop block next to the stick to keep it from unwinding before you want it to.

EDIT:

You can see what I am talking about here http://lumberjocks.com/projects/98276 Yuri used it on his tool cabinet build. Just scroll about halfway down his description and you will see a pic of the process.


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## NiteWalker (May 7, 2011)

Any strong tape will work fine.


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## Finn (May 26, 2010)

When I do this kind of construction I always put a gusset inside each corner with plenty of glue. I pin nail it in place to hold the gusset in place until the glue sets.


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## shipwright (Sep 27, 2010)

If your mitres fit all you need is the tape. Blue masking tape works well but if you want to be able to inspect the fit at the corners you can use clear packing tape. Clamping in cases where the fits are good is overemphasized. If the pieces touch the glue will get it done. If they don't, you need clamps.

If you want to add a little pressure you can wrap bungee cord around it. A length of it is cheaper than band clamps.


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## MontanaBob (Jan 19, 2011)

I've been using these clamp blocks, as shown by ([email protected]). I've made them several sizes. Works fast easy. I'd probably use a band strap around the middle of a piece this size, to make sure everything was tight…


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## ellen35 (Jan 1, 2009)

Doug Stowe, a master box maker (we have many master box makers on LJ too), turned me on to packing tape. Check out his website, books or articles. It is simple and costs nothing to do. It works great too.
Ellen


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## LeTurbo (Jan 22, 2014)

Here's a cunning trick I picked up recently. Dry assemble the joint by clamping it to a strap hinge (those ones with long sides). You can now open the joint to apply your glue, and close the joint again in the exact position you'd dry-fitted it. You can then apply a strap, or even rope (put a stick through a loop and twist to tighten).


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## MBD (Mar 28, 2013)

I glue all of mine up the same way Shipwright and qfadvm do theirs. Most of the time, blue tape or duct tape is enough to hold until the glue dries. Look at Andy's art box blog, he explains this procedure well.


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## Earlextech (Jan 13, 2011)

Masking tape - stretched. Never had a problem.


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## DrDirt (Feb 26, 2008)

Band clamps are great.
To get it all together I use blue tape generally.

If I were doing something as large as you showed - I would use some kind of filament tape so I could pull on it and reposition things without the masking tape tearing.


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