Intro: Door Trimming Jig
When we moved into our house (built around 1900) we found that none of the doors where of a standard size or shape. I some cases we had to add batons to the top and bottoms to increase the sizes in others pack out the frames so that a modern size would fit. The problem came when the frames where already too small for a modern standard door. I don't have a bench top planer, cutting the doors with saws did not give a good edge and hand planing could get very uneven.
So I came up with the following very simple jig for my electric hand plane.
Step 1: Parts
The jig is made up from two separate parts
The Plane "frame"
I traced one side of my plane onto some paper (the motor side in this case) and transferred it to a piece of 12 mm MDF making sure that the side of the tracing closest to the cutting surface of the plane was paralell to a straight edge on the MDF - this is needed to run along the rail. (the MDF only needs be thick enough to support the planer and hold securely onto the motor).
I then cut out the transferred drawing - I cut a little inside the line so that I could sand the remaining materials to ensure a tight fit on the plane. My plane has a hole in it for a side guide and I used that to hold the frame to the plane with a bolt.
The Rail / Runner
I then cut two lengths of MDF (12 mm thick) one piece 3 cm wide and the other 1 cm wide (both where long enough to match the height of the doors to be trimmed)
It is important that the 1 cm length is the same thickness as the material used for the frame.
The two lengths where then glued and screwed together to form an "L" shaped rail or runner once the glue was set I drilled a series of holes through both lengths - these are used to secure the rail to the door using small screws
Step 2: Set Up and Use
Attach the frame to the plane and ensure that it is tight on the motor housing also that the frame edge is parallel to the cutting surface of the plane.
Measure the distance from the heel of your plane to the parallel edge of the frame (I use a set gauge so I am sure to use the same setting for the length of the cut)
Use that distance to fasten the rail to the face of the door checking the distance with the gauge before putting each screw in.
put the edge of the frame into the runner (with zero cut set it should just move nicely along the rail. If it snags at any point just loosen the closest rail securing screw a little)
Now set the cutter depth as you would normally (depends on your particular tool) to the amount to be removed and start planing until the frame edge meets the rail - job done (apart from filling a few small screw holes in the door.
What if you need to remove more than you plane can be set to?
Just add the extra distance to the size set for the gauge and complete as above.
This jig also works well on tappers for example chair or table legs. Just gets a little tricky holding the material to be cut - one way to do that would be to oversize the 3 cm baton to make an exaggerated "T" shape and clamp that to a bench while planing
Thanks for looking
This was just a quick Instrucable If you like this please take a look at my other instructable's or at my web page: http://handycrafted.jimdo.com/