At three o’clock in the morning my brain usually wakes up. It then starts to worry about random things. In an effort to stop this keeping me awake for the rest of the night I generally give it something real to worry about. Like how on Earth do I perform EZ Mitre on a box with only 17mm of contact at each corner. To illustrate
The four black corners at the top have joints 17 mm long to the sides. Scary. This seemed to be enough to divert my waking mind. Well it said you’ve got that 116 mm sq. x 18 mm piece of MDF that fits snugly in the centre of the pattern.
Put it back in and then I suggest you do this, cut a 90 mm wide piece of 6 mm MDF into three pieces, thus
Then re-arrange the two triangular bits like this
and join them together by gluing the third bit across them like this
Very nice I said to myself but then what?
Use them as a cutting jig!
This allows you to cut off the excess all around the board. Set the blade height to just over the board thickness (8 mm to be on the safe side) and set the distance to the fence to 90 mm minus the height on your drawing of the corner of the 116 mm jig from the box base. 90-30 =60mm, to the left hand side of the blade. Then cut the excess off so
Do this for the first three sides then adjust the blade height to completely cut through the jig as well on the fourth side.
Now you have a board like this
and a distance jig for your EZ-Mitre routing that will also hold down that little top triangle and stop it flying out.
Well OK, if you say so but I’m not convinced.
Trust me I used to be an engineer.
So I taped up the mitre lines and re-inserted the square jig. Placed the new distance jig on and routed the first side.
And so on rotating anti-clockwise on all four sides. Looking at the underside I was sucessful
Yipee! I cut out the four corners with my scalpel and glued and taped it up.
The Eagle eyed amongst you may have spotted what you think is a flaw
Already sorted. This came up as an issue during the 3D modeling in CAD. There will be four inserts made and glued in to cover this ‘gap’. The rest is as for normal Shell box construction so the next time you see this should be in the projects section in a short while.
Be seeing you
-- Martyn -- Boxologist, Pattern Juggler and Candyman of the visually challenging. http://www.theartofboxes.com