Wednesday, March 28, 2018

Day 170: Bending, Rebending and Joining

The bridge saga continues. After I had recut and rebent the 8' and 4' bridges and matched them up to the plans, I realized they would need another steaming session. I finally ended up with a nice Owen-approved curve, but not until steaming and bending them twice. I've been told woods will not take to bending once they've been bent because something magical (which always goes unspecified) happens to the lignin (the complex organic polymer in all woods) once it's been heated and bent. I can say with complete confidence that this is untrue. So, I bent the bridges twice until I got the curves I felt I deserved.




I shot Owen a quick email with the last photo above and he responded with encouragement, so I decided it was time to get the hook tacked onto the bass end of the 8-footer. I went with a half-lap joint because I've used them with some success in the past. Rather than scrape and spokeshave the hook to death, I used the Ridgid oscillating spindle sander to smooth the band saw cut marks down in record time.


I then cut the lap joints on the table and band saws and took to gluing it up late last night.



I should have a stable joint in the next couple of days. Then, I'll cut the bevels (on the correct side this time) and, as Owen would say, "Bob's your uncle." I really have no idea what that means, but it sounds really cool.

Until next time...

Wednesday, March 21, 2018

Day 169: Bridge Bevel Bonanza

UPDATE: Owen just told me I cut the bevels on the wrong side. This was based on the image below in Mr. Miller's eBook Most Excellent that I've surmised illustrates the nuts, not the bridges. Sure, it's a little frustrating, but what the heck, practice is good. Back to the drawing board - literally. Besides, it gives me the chance to tack the hook onto the 8' before cutting the bevel.

Image from The Harpsichord Project E-Book 4.0 by Ernest Miller.

As you know from previous posts, I've been preparing to cut the bevels into the bridges for some time now. Frankly, I was scared sheetless to do it because I couldn't bear the thought of ruining another set, but, hey, it's all good, right? Fortunately, I attended a Western Early Keyboard Association (WEKA) event recently and was able to get a good look at some example instrument bridges. Owen Daly was in attendance and was kind enough to give a short clinic on making bridges, which also helped enormously.

I took photos of the instrument at the event, but it turns out they're not very illustrative. The rub for me in cutting the bridges was related to how wide the top of them should be. While Owen was telling me they should be a consistent size (pretty thin) from the larger to the smaller ends, Mr. Miller's eBook Most Excellent describes a top thickness that is variable from end to end. After viewing the instrument at the WEKA recital, I realized they could (should?) be the same width from one end to the other - no disrespect to Mr. Miller whatsoever. And, as Owen said at the WEKA event, "The bevel angle should be determined by the width of the top of the bridge before the outside bevel is introduced, not by an arbitrary degree measurement."

I know this may all be a bit abstract. At the end of the day, Flemish instrument bridges end up being weird variable trapezoids that change in size from one end to the other. The 8' bridge is 3/4" at one end and 1/2" at the other and the 4' is 1/2" to 1/4". I'll be illustrating in greater depth how they work in subsequent posts - it's really too much to fully explain here. Suffice it to say the bridges act as terminal resonance points for the strings between them and the nuts - just like on a guitar. On both instruments, the termination points of the strings (i.e., where they are secured to the instrument) are less important than the location of the nuts and bridges because the distance between those points determine the notes played by the strings.

Whew. Just a second, I need to catch my breath. Okay...we're back. Now, Mr. Miller has devised an ingenious way to cut the bevels into the bridges BEFORE BENDING them. Owen, on the other hand, cautioned me against this approach due to the potential for twisting post-bend. As always, I was willing to give Owen's recommendation(s) a shot and went ahead with the cutting, steaming, and bending of both bridges.

As you may recall, I tried bending the bridges using the bentside form. Not a good plan. This time, I made the 8' bending form, steamed the bridge, got it onto the form for a couple of days, and, viola! - it actually worked. A nice, curvy, uniform bend with little springback was the result.




I was so pleased with the result that I forged ahead with setting up a 4' curve on the same form and got the 4' bridge steamed and bent.



Now, this is where I took a pretty substantial break for fear of screwing up (again). Once I gathered up the requisite fortitude, I went ahead and set the band saw at 30 degrees and ran a test cut.


When I compared the test against the "old" bridges, it was a nearly perfect match, so I went ahead and cut the 8' bridge bevel.


The next step was to clean up the band saw marks. I initially used a spokeshave, but found it to be a bit rough, especially since I had not honed the blade after purchasing it. In the interest of expediency, I switched to the Lie-Nielsen low angle block plane, which made quick work of the cleanup.


I was so pleased with the result, I moved on to cleaning up the 4' bridge, yet I found that a little ebony luthier's plane worked best on that one. The added benefit was that the ebony burnished the wood as I planed it down, resulting in no need to scrap or sand.


Still, there remains the matter of adding the hook to the bass end of the 8' bridge. This part of the bridge curves at too sharp an angle to bend on the form, so we just cut one to angle and tack it onto the bridge at just the right place. In the photos below, I'm tracing it out and preparing to cut it, but, alas, it got too late and I didn't want to suffer from spousecide (she goes to bed much earlier than I).



On a couple of completely unrelated notes, I am now and probably always will be a sucker for swag.


I'll most likely order a few, but with our tag line "Tardus et stabilis..." (Latin for "Slow and steady...") and the web address. The quality of the pen is pretty high, which is nice.

I also got the dust boot installed onto the CNC machine, which is the culmination of an interesting story. When I picked up the machine after driving to Waldport, Oregon from Vancouver, Washington - about a 4 hour trip each way - I asked Cool Craigslist Guy about the dust collection he advertised on the CL ad. He said, "Oh, yeah, here it is," and handed me a Dust Deputy funnel and sawdust bin. I thought, "Well, okay, I guess I'm saving enough it doesn't really matter."

A couple of days later, I received an email from him saying he forgot to give me the Suckit Dust Boot (you know, the dust collection he advertised on CL) and that he would be shipping it to me post haste. All good, right? Well, when I got it, I discovered so many parts were missing it rendered the boot unusable. So, I contacted the Suckit people to see if I could purchase the missing parts. The wonderful person there said, "We love the fact you purchased it on Craigslist. If you send me a photo of what you have, I can send you what's missing."

After emailing Jenn a photo, she let me know they'd be replacing the missing parts and shipping them to me free of charge. Holy cow, I was flabbergasted. In a consumeristic society like ours in which everything has a price, a company exists that cares more about customer satisfaction than making a buck. My hat's off to the Suckit people - you rock.



The assembly was made easier by following a video on their website and I now have a CNC machine that looks an awful lot like an elephant. If it keeps the shop largely free of CNC-created sawdust, I'll take it.

Until next time...

Tuesday, March 13, 2018

Day 168: Bridges, Bridges, Bridges

As much as I wanted to shoehorn the bridges bent on the side lamination form into the proper angles, they just were not acceptable. Owen Daly could tell from the photos I posted here and on Facebook that they were not okay and it was at his adamant encouragement that I embarked on a rebending exercise for the 8' bridge (the 4' will be next, but only if this works), only this time using a form I made on the original sheet of plywood I used for the first failed iteration (yes, I'm on Bridge Adventure #3).




As you can see, I ordered a dozen spring clamps and waited a week for them to arrive before embarking on the bending session. This time, I also steamed the bridge using my custom setup, rather than soak it overnight.



We use only the highest of tech here at Tortuga Early Instruments Worldwide Headquarters.

I steamed the 8' bridge and got it into the form using clamps I already had - they clamped tighter and held better. I ended up using only a couple of the spring clamps, but I'm sure I'll find a use for them from time to time.


The bridge currently sits in the form. I'll remove it toward the end of the week to see what we have to work with. I'm also waffling about running them on the band saw. I have a razor sharp drawknife and that beautiful new Veritas spokeshave - they should both make quick work of beveling should they not?

Speaking of Veritas, I made a management decision a couple of weeks ago. I decided that jointing anything in the shop will be done by hand moving forward. This meant I needed to dispose of the Delta 4" knuckle-shaver and convert all jointing activies to using hand planes. Cool Craigslist Guy purchased the jointer the first day I listed it.


The empty space is where it once stood. So much more room for activities. It was replaced with a Veritas low-angle/bevel-up jointer hand plane. While I was at it, I decided to go ahead and pick up their low-angle/bevel-up smoother, as well. The default blades for both of these planes are a 38-degree beauty. I'm not going to get into a discussion about the merits of bevel-up vs. "regular" planes here. There are plenty of other fruitful places to argue which is better/worse. I prefer bevel up. Period.

I will say, though, that on bevel-up planes, specific angles accomplish specific tasks such as hogging out more wood with a minimum of tearout or nearly emulating a scraper. In this case, the 38-degree blade combined with the 12-degree bed provides the basic 50-degree York cut that so many favor for smoothing. Since the 2 1/4" width blades are interchangeable between the planes, I also picked up 25-degree and 50-degree blades. There are many subtleties associated with using low-angle/bevel-up planes, including how microbevels are honed, etc., but, again, this ain't the place.

So, we welcome these two new team members to Tortuga Early Instruments.


The gadget at the bottom of the photo above is a jointer fence what will allow me to joint vertically, rather than setting up, say, an 8' horizontal shooting board, using the Roubo bench leg vise while not introducing unintended bevel into the process. If you've ever tried to freehand a joint, you'll know what I mean. Like the planes, the fence has a tiny, little set screw to keep things lined up and accurate. I also had a cleaning session to get the shipping/preservative goo off of the team members.


A little mineral spirits followed up with a some Boeshield T-9 (I silently thank Random Roger Green for introducing me to the stuff everytime I use it) will keep these fellas in good working order for many years to come. Who knows, I may even sell the Lie-Nielsen No. 62 and go with a Veritas low-angle jack, we'll see (John - that Lie-Nielsen large scraper is staying with me, sorry).

Until next time...

Tuesday, February 27, 2018

Day 167: Bridge Update

After reviewing the bends in the bridges via Facebook photo, Owen Daly declared them inadequate. Dammit. Now, you know that I always take Owen's comments seriously - all of them. So, this time, I compared the bridges to the plan and, while Owen is right - the lower end of the 8' needs a little more roundness - I believe I can achieve that with a little extra bending to bring it into shape. The 4' will work just fine.




And I still get to cut them on the band saw with its table tilted at 30 degrees. The fun just never stops.

On a tangentially related note, neither travel to the Oregon Coast nor food poisoning will stop the acquisitions at Tortuga Early Instruments. I mentioned the new CNC machine in a previous post and, well, here it is assembled and ready to go:



Cool Craigslist Guy sold it to me as an XL (19" x 33" cutting area), so I expanded it to XXL with an extension kit from the manufacturer, Carbide3D. This required basically gutting the thing and reinstalling the y-axis rails, as well as all of the wiring. Fortunately, everything was clearly marked and their online installation instructions are top-notch. I was able to test their Hello World design with a felt pen taped to the router and it worked just great.


I then realized I needed a dedicated computer of some kind to run the machine. The technical requirements to run Carbide Motion are not too bad, so I settled on an Insignia tablet I found on eBay for $200. Right before clicking the Commit to Buy button, I decided to give Craigslist a shot and, wouldn't you know it, another Cool Craigslist Guy was offering an 11" Windows 10 tablet with a keyboard, an extra 128gb SD card, and a Swiss Army case for $40. So, there you go.


The thing is tiny, but looks much bigger in the photo. Regardless, it runs the software just fine. What will I do with the CNC contraption? Well, I've already been approached by an experienced harpsichord builder to explore cutting intrument registers (jack guides) on the thing. The tolerances at which the machine cuts are just right for this sort of operation and I may or may not have other mini-projects in mind, as well. I'll keep you posted as this new tool continues to transform the way I cut wood.

Until next time...

Friday, February 16, 2018

Day 166: Recutting and Rebending the Bridges

As you know from a previous post, I decided to recut and rebend the bridges. The first attempt resulted in bridges that were less than cosmetically beautiful because I used non-stainless nails to hold them in place for the bend and they stained the wood. And, well, nail holes. So, after talking things over with both Ernie Miller and Owen Daly, I decided to create bridges using both of their methods. As in making two new sets of bridges. Then, I came to my senses and developed a hybrid approach.

I picked up some double-sided carpet tape at our local blue box store and grabbed the form I had used for the initial bending episode. I started with the 8' bridge assuming it would be easier to work with than the 4'. For once, I was right. I taped it to the plywood on a taper running from 3/4" to 1/2" and ran it through the table saw.



As you can see in the top photo, the beech board had plastic wrap around it. This was due to the fact that my friend, John Finn, donated the wood to the cause and it was raining buckets the day I picked the piece up at his house. He was kind enough to wrap it and there you go.


The tape held like, as Owen would say, grim death and I was able to cut the width and height to the dimensions I described above for both the 8' and 4', resulting in a couple of blanks that are just a fraction rich so I'll have a little room when it comes time to trim them down with the spokeshave.


The previous bending session went well by simply soaking the bridges in a water trough I made from some 4" PVC pipe capped with Talenti gelato lids and Gorilla Glue. I've been given the recommendation to also use a steamer, but I found all they really need is to soak overnight. They are super-thin pieces of wood and this is what Mr. Miller recommends in his eBook Most Excellent.



Yeah, that's a rock from the front yard and yeah, I cleaned it in this kitchen sink first with soap and water. When I checked the bridges the following morning, I noticed that the 4' had jumped ahead and started bending itself without me. I was not alarmed because it almost perfectly followed the angle I would be putting upon it with the form.


This may become problematic if it decides to twist, but I've been keeping my eye on it as it stands in the form and it looks pretty good.

Speaking of forms, rather than mess around with a custom jig, I went ahead and used the bentside form as Owen suggested in another one of our conversations that ended up with me saying, "I don't know." The question: "Why don't you just use your bentside form to bend the bridges?"


So, now they stand in the shop drying for a week.


And I remind you that this is a hybrid approach based upon suggestions from Ernie and Owen. I'll be cutting the bevels into the bridges on the band saw as soon as they're dry, which will get a blog post all its own.

Until next time...

Monday, February 12, 2018

Day 165: Beveling and Some New Gadgets

As you may or may not know, I've recently been sick yet again. Not only did I pick up "stacked infections" - sinus and urinary tract - I got food poisoning from eating oysters at the Oregon Coast. If misery loves company, I'm overwhelmed with the turnout. Now, having whined about that, I can say with 100% confidence that all illnesses have left the building - and my body. I'm good to go, so here we go.

After conferring with both Ernie Miller and Owen Daly about completely different ways to approach cutting and bending the 8' and 4' bridges, I've decided to pursue both methods and then compare and contrast the differences between the two. In the end, I really just want to get them done - as soon as I can figure out how to cut a 30-degree bevel on the table saw.


I'm mostly kidding. A good buddy, John Finn, is visiting later today to chew the fat over the best way to accomplish the bevel. Honestly, I believe it involves tilting the the saw blade at the complementary angle to 30 degrees (that's right - 60 degrees) and ripping the beech board with the fence set very close to the blade. More on this later.

Over the last few weeks, I've engaged in my regular Tortuga Early Instruments Worldwide Headquarters Winter Cleanup, including selling the Laguna 14" SUV resaw band saw and dumping that money into a nice, little CNC machine - the Shapeoko 3 XL. I purchased it from Cool Craigslist Guy in Waldport, Oregon (hence the bad seafood story) and saved a cool $1000 off the regular price from Carbide3D.


I've since ordered the XL--> XXL upgrade kit to double the y-axis depth of the machine. Will I be using it for harpsichord work? Probably not, but it definitely changes the character of some of the other (ahem...guitar) work I do.

Along with this, I finally broke down and replaed the $7 spokeshave with this:


The Veritas Flat Spokeshave, O1. As I've said in the past, the poverty mentality that accompanies being the Cheapest Guy Alive no longer applies to the shop. From now on, it's heirloom quality tools for me. Another example of this sort of mentality is the former CNC machine that took up space for over two years under the assembly table:


Heirloom. Quality. Tools. Moving. Forward.

Speaking of heirloom quality tools, I also brought a Grizzly air filter into the shop. It's not really heirloom quality, but it does filter dust at the 5 and 1 micron levels. I'm really, really, really hoping this, combined with greater attention to dust collection at tool origins, will help me cut down on the bronchial/sinus infections I've been enduring the last couple of years. Maybe it will, maybe it won't, but I'll take that bet.



The little unit offers three speeds with three timer levels: 1, 2 and 4 hours, so I never have to remember to shut it off. I did the "flame test" by holding a lighter in various areas around the shop and I must say I'm impressed with its coverage. Grizzly claims it will recycle the entire shop air seven times per hour and I'm inclined to believe them.

Now, back to cutting that bevel.

Until next time...