Kim Block: Cutting in Wood

This post is called Kim Block: Cutting in Wood. It could just as easily be called Kim Block: In Which Many Mistakes Were Made. The learning curve for this project has been a little bit steep but the troubleshooting aspect of cutting in hardwood was a whole different story.

The first questions that needed to be answered were:

  1. “What kind of wood?” and
  2. “Where can I get that kind of wood?”
  3.  “…… but it’s the wrong size what do I do now?”

A quick survey of the hat blocks held in stock at UNC’s costume shop and a consultation with our resident expert Rachel Pollack (author of the wonderful blog LaBreicoluse) revealed the answer to the first question. Hat blocks are typically made of basswood, poplar, and balsa. These woods are popular materials for hat blocks as they are all soft hardwoods. Their relatively low density means that they can easily be nailed into as part of the hat blocking process. In addition they are easy to carve and relatively inexpensive. Of the three balsa is by far the least expensive and also the least sturdy. Balsa is one of the lightest and least dense hardwoods and blocks carved from it tend to take damage more quickly.

I was able to source my wood from the Hardwood Store in Gibbsonville NC. Based on their recommendation, I elected to use basswood. They had tried running poplar on a CNC router before and found that the wood tended to shred. Unfortunately (but not unexpectedly) they did not carry wood in the dimensions I required, however for an extra few dollars they glued up smaller pieces to make a piece of the correct size. They did a wonderful job and the glued seams caused no problems during the cutting or finishing process.

Everything was looking good as Sallye and I ran the roughing pass.

Then as the finishing pass ran, disaster struck. During the process of gluing together the basswood board the Hardwood store had shaved of 1/4 in to ensure that the glued pieces were level. They had warned us of this and we had adjusted the cutting files to reflect this change in material depth. Unfortunately we had missed something somewhere along the way and the pieces were cut incorrectly. Resulting in a block that looked like a topographic map instead of the smooth curves I needed.

We now had to fit a new set of block pieces onto the remaining wood. Fortunately, since I had intended to make three blocks over the course of this project I had purchased three 18 x 14 x 2 blocks and we were able to re-work our cutting files to fit in all the pieces.

Then as we were cutting out the bottom most layer the machine started to get stuck and burning the wood. We couldn’t find a problem and decided that it must be some problem with the wood in that spot. However, upon cutting it again in a different spot with the same result we were baffled. We circumvented the problem by changing the way it was cut entirely and moved on.

At this point, I would like to emphasize one crucial point. I have no wood working experience. This is my first woodworking project. I am a total novice and have had to learn all of the skills and processes related to the finishing of these blocks as I went along. So I apologize in advance for my abysmal finishing techniques and poor finishing choices.

The whole cutting process took several days as problems arose and were solved. In the end, we had enough of each piece to make the three blocks I wanted. The pieces were a bit rough and the layers did not fit together quite perfectly but after hitting them with a belt sander and then some hand sanding they were looking pretty good. However, in keeping with the rest of the project, there was a problem. The Hardwood Store had warned me that poplar would shred under the CNC router. It turned out that, basswood does too. I should have guessed that basswood would react to the CNC in a way similar to the poplar. The low density of the wood, the very quality that makes both woods so good for hat blocks, was the quality that caused them to shred on the CNC. This required extensive sanding with progressively finer grits of sand paper and a lot of elbow grease. In the end, I couldn’t totally eliminate the shreddyness but I hoped that the finishing would help keep it subdued.

Once the pieces had been sanded I glued and slotted the pieces together using dowels through the guide holes to align them just as I had done on the foam version with the slight change of using three holes instead of two for better accuracy. Once the glue was dry, I sanded the blocks again to make the blocks flush at the seams.

I used wood putty to fill in any remaining gaps and cracks in the blocks. Next I cut the rope lines around the bottom of the block. The original hat showed evidence of a rope line around the base of the crown. I elected to cut only the bottom rope line because I was unsure of the technique I was using and didn’t want to gouge the crown by accident.

The next step was to stain them. The color variation that is evident between the blocks is caused by me forgetting to stir the stain properly before use. The blotchiness is caused by the stain absorbing unevenly over the wood putty.

Finally, I sealed the block. Please pardon the bad lighting in these pictures, I will have better ones soon.

Over all I think this project has been a success. It has demonstrated that creating a block from a hat is a viable project. It’s true that this block is a little bit ugly but functionally it is entirely sound. I have learned a lot over the course of this project and future iterations will definitely be more skillfully assembled. I am excited for the possibilities that this process has for the preservation, restoration, and reproduction of antique and vintage hats.

The next step is to distribute my blocks and see how well they work! Stay tuned!