Handle fitting in 2 piece infill
Reader directed blog posts are a great. I have mentioned before that generating content is becoming increasingly challenging. I am reluctant to start recycling earlier topics, but it feels like I am at a point where there is not much ‘new’ to say. So questions or requests from readers are extremely helpful.
This post was initiated by Owen and a few others expressed interest in it as well - so here goes.
The question has to do with construction and fitting the handle into the rear infill of a large plane. The rear infill is a single piece of wood and the handle is a separate piece of wood. The handle is mortised through the rear infill right to the bottom. I have seen many original Spiers and Norris planes where the handle is not fully moritsed into the rear infill... and the fact that I have seen this points out the flaw of this approach - they often come loose. They were usually just glued in - without the additional strength of a cross pin - which is shocking really. I always have 2 pins pass through the handle - it just strikes me as good, sound, mechanical strength.
I make a square mortise in the rear infill and then fit the handle to the mortise. The mortise is sized a little smaller than the handle blank - usually by less than .0010". Once the rear infill is fit, I start fitting the handle.
Oh, I should preface this entire process by saying that I am not a militant numbers guy. I do not work in such a way where a handle would fit into another plane - it will only fit the plane I am working on. I have zero interest in making a pile of metal pieces and a pile of wood pieces and have them be able to fit with each other interchangably. I would rather gnaw my arm off than work that way! I don't need to have all the handle blanks be 1.120391" wide - I rough out a handle to somewhere between 1-1/8" and 1-1/16" wide and put it on the shelf until it is needed. But... I do use calipers all the time because the fit between 2 parts does require paying attention to the numbers. I don't care what the specific thickness of the handle is - but it has to be consistent at each corner to within 0.001". I hope the difference makes sense.
These previous 2 shots show the handle slipping into the rear infill. I should also mention that the fit between these parts is incredibly tight. The rear infill is just a pressure fit, but is good enough that it could support the weight of the metal shell if lifted. Even at this stage, the handle could also support the weight of the shell and rear infill if lifted.
With the handle bank to the correct thickness, I can now mark the notch at the back of the handle. This struck me as the best approach to dealing with the rounded back of the handle - have it overlap the rear infill as opposed to try and cut a precise radius in the rear infill. I am shaping the handles freehand and don't want to have to bother to worry about the precise radius I file - this process allows me to work the way I want to.
The shot above shows the cut-out notch. At this point, I fit the handle fairly close and will make adjustments to the notch so it rests quite flush with the rear infill. I do not worry about final adjustments until the handle has been shaped though - no point in fitting areas that will be filed off in the shaping process.
Here is the handle roughly shaped - and the files I use to get there.
With the rear of the handle roughly shaped, I now start to fine tune the fit between the rounded back and the deck of the rear infill. I use chisels and files to fine tune the fit until there is no gap between the handle and rear infill. The shot above and below show what it looks like.
The next 2 shots show the handle fully shaped, sanded and placed in the rear infill as a final check before gluing. Please click on any of the images to get a larger view.
I use polyeurathane glue for a couple of reasons. Firstly, it has a long open time. Secondly, it has no gap filling properties - so it forces me to work very precisely. Thirdly, it was originally designed for gluing Teak and none of the woods I work with are that oily so I figured it would be a good choice.
The shot above shows a small curl of glue being chiseled away. Click on this image to see a larger view to show the fit between the handle and the rear infill.
A final shot of the rear infill with the glue squeeze-out cleaned up.
I hope this helps Owen - and thanks for the topic suggestion.