mock-ups - expanding the family

I suppose it was only a matter of time before the KS-1.5 would have siblings. The question for me was, are they just narrower versions, or are they fully scaled? I was on the fence about it for a few days, but in hindsight, I think I knew all along that scaling was the right call (and a great design challenge). A good friend gave me an affirming nudge towards scaling and the design process began.

Scaling work is usually not as simple as just shrinking something down by 10-15%. On rare occasions it works, but it is usually obvious, and leads to a host of issues. The biggest issue with scaling a plane is that our hands do not scale along with it. I was pleased to see that the design scaled very well, and with some tweaks in a few key areas (the shape of the wedge, the scoop at the front), the drawings looked good.

There are four additional sizes, 1-1/4" wide, 1", 3/4" and 1/2". I made a 1/2" x 6" shoulder plane several years ago and loved the size of it. That seemed like a logical plane to reference for the smallest version. I decided to mock-up the smallest plane first - the thinking being that if I had the largest (1-1/2") and smallest (1/2") planes figured out, the planes in between should be easier.

I also decided to make a mock-up of each plane. Mock-ups have proven to be an invaluable part of the design process. I learned to make mock-ups in design school but for some reason, it took me a while to apply the methodology and process to plane making and furniture making. I have fully embraced it now, especially when dealing with curves. It can feel like a waste of time when you are in the middle of it, but there are always those ‘aha’ moments when you realize something significant, and are suddenly grateful you are not working with expensive materials. I spent a week making a mock-up of our dining chairs, and it proved to be the most valuable week of the project.

The other advantage of mock-ups is it allows me to practice process. I have gotten in the habit of keeping the shop camera close at hand to photograph all sorts of stages of work. Reviewing these photos is extremely helpful when I need to remember what the heck I did earlier. But process is not just about seeing how things are done -it is about practicing the movements of the actual work. Shaping the front pad on the first K13 took hours and hours of careful, methodical work. It was a completely new form for me to shape and the curves are rather complex. I have made quite a few K13’s since the prototype, but I had the prototype at the bench for a reference as I worked on subsequent planes. After shaping 5 or 6 more K13 front pads, I had the movements memorized and no longer needed the prototype for reference. The shapes and curves on the KS-1.5 were even more complex than the K13, and I was happy for the practice on the 4 mock-ups.

I even went so far as to trim the ‘Mahogany sidewalls’ from the ’infill’ to accurately reflect what a real plane would be like. It felt a little silly to take it this far, but it went a long way to learning the movements and the process of shaping.

Quick layout lines for the chamfering.

I wish chamfering 01 tool steel was this easy!

Here are several photos of the set of 5 mock-ups to show how they scale. There are going to be a few more tweaks to each of the final drawings before I make the prototypes, but I am very happy with how these turned out and am confident that they are close enough to proceed. I am also looking forward to having my own set of these - all in African Blackwood like the KS-1.5.

And related to shoulder planes, I received an email last week from someone who is interested in making their own shoulder plane. He asked if there were any tips I could pass along as well as how the blade on a shoulder plane is installed and removed. I took a few photos to show the process.

 The blade slips into the plane from the back at an angle. When designing a plane, the diagonal distance between the bed and the keeper (the metal insert that is twin tenoned into the sidewalls) needs to be wider than the blade in order for this to work.

Another view of the above image. Notice how the side of the blade is now completely visible. This is also important because it allows you to shift the blade to one side....
 

 ... like this. The other side should now be clear of the sidewall too. You may need to push the blade forward a bit more - like in the below photo.

And then you can just drop it down onto the bed.

Grab the wedge, let it drop into position, give light hand pressure and you should be good to go.