Wednesday, June 8, 2016

Day 118: Back to the Reason for the Season

Well, the Roubo-style workbench is finally wrapping up. I'll have the thing completed over the next couple of weeks. Random Roger Green has been generous with his time and tools and the insights he's given me not just about the bench project, but woodworking in general, will continue to prove useful to me for the rest of my days. Thanks again, Roger - you're a gentleman and a scholar.

This past week, Random and I worked on test fitting the legs. As expected, there were a few challenges that were handled with some joinery float work. I must admit that it was a bit tedious jamming the legs in and then using a clamp to push them back out, but it was a necessary exercise. And Random did most of the heavy lifting. Literally.

The process was to jam a leg in until it would jam no farther, pull it out, observe any shiny areas under proper light, and shave the tenon with a float to remove the obstruction. This also went for the mortises where I shaved a bit off using a float, as well. The result of this hard work is a bench ready for top, leg, and leg stretcher assembly. We'll be using the drawboring technique, which I will explain in detail later this week.

On a completely unrelated, totally salient and exciting note, given the state of the workbench, I decided to jump back onto completing the instrument - the point of the workbench exercise and this blog. If you found my workbench posts boring, my apologies. I simply considered them an important part of my build process, one that often requires me to take two steps back after having taking a good, solid three forward. I'm still building out the shop for harpsichord making and posting about go-bar decks and assembly tables and workbenches is part of my effort at being completely transparent about my work.

As you may know, I'm following the detailed directions carefully laid out in Ernest Miller's Harpsichord Project E-book 3.1. It's highly unlikely I would have embarked upon this project without Mr. Miller's book and I'm grateful every day that he took the time and effort to create it - and that I was able to find it on the interwebs.

The first step in reacquainting myself with the project was to review the parts and pieces I had previously cut. To review: I found I had prepared the bottom, spine, cheek, bentside, tail, lower belly rail and pinblock. Considering these parts, I went back to Mr. Miller's eBook Most Excellent and saw that it was time for me to cut a couple of pinblock support blocks out of some of the red oak I had on hand.

Once the pinblocks were cut and drilled to satisfaction, I grabbed the bottom to lay it down so I could review the fits of the case sides and found that the keybed section had begun to separate from the rest. This was not good and, frankly, I don't believe I would have discovered this had I not taken the long, unforeseen break to build the workbench. I quickly remedied the situation with some Garrett Wade Gap Filling Glue.

I'm honestly not sure what this speaks to. Was it my lack of woodworking experience or my typical haste that caused this problem? Regardless, it's a learning opportunity that I don't take lightly. This sort of thing is completely unacceptable and I'll be more careful with my jointing in the future.

Once I fixed the bottom joint, the next step in Mr. Miller's eBook Most Excellent was to glue the pinblock to the case sides. I had already routed the sides and test fitted them a few months ago, so I was confident everything would go together nicely.

I must admit one concern: the lack of tuning pin holes in the pinblock before glue-up. I would much rather have preferred drilling these on the drill press before the glue-up, but I've learned that deviating from Mr. Miller's directions is a cause for disaster (see my tail comments below). The next step was to glue up the lower belly rail, so I flipped the structure over and went to town.

Things were going nicely until I got to Mr. Miller's instructions about cutting the tail to length and setting its end bevels to match the spine and bentside. In my infinite wisdom, I had charged ahead months ago with the tail sizing and bevels - without following Mr. Miller's directions. The result: a tail that was too short - it met up with the inside of the bentside outline on the bottom, rather than the outside of the outline. Once again, I proceeded where I saw fit and the outcome was a tail that simply could not be used.

It looked great, but I believe the reason it must be on the outside of the spine and bentside lines is to act as support for the ends. This is important when the strings begin to pull on the case. I then recut the tail to the proper dimensions (following Mr. Miller's directions) and realized I could save the useless tail to act as a table saw angle template for future instruments - should I make another one based on Mr. Miller's plans.You can see in the lower right of the photo below where the tail terminates on the outside, not inside, line on the bottom.

It's a great feeling to be back to work on the instrument. The workbench may have chopped 90 days out of the instrument build timeline, but it will be worth it in the long run to have a perfect bench for hand planing, etc. For now, I'm enjoying the process of creation once again.

Until next time...

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