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Nicely bound and I like that shape! It looks like it will be comfy to play.

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George :-)

I have gone ahead and zoomed through the rest of the process on CN#2, and today it went into finish. Here are a few pictures with the sealer on:

















Sharing in a thread like this is a social function for me, and the more YOU interact, the more I will.

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Bruce Sexauer, luthier
http://mojoluthier.com

It’s a beauty! What’s on the dovetail? The yellow stuff? Is it chalk or some indicator used when fitting the joint? I’ve never done anything but M/T so forgive me if it’s well known.

Brad


Sent from my iPhone using Tapatalk Pro

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That was fast.

How do you go about shaping your necks - bandsaw, drawknife, spoke shaves. rasps, scrapers? How do you hold it in place while shaping?

Do you attach the fingerboard during final shaping and how do do arrive at the final shape? Do you just feel it or do you use profile templates for say the 1st & 10th frets then connect the surfaces or some other way?

Following your threads have helped motivate me on my current re-top project that's going to get a new neck too. I had experimented with making an L-00 13-fret with "long" 25.4" scale based upon a 14 fret, short scale plan. After 7 years it resulted in a severe roller coaster top and a very deep tone that I didn't care for.

Thanks,
Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

The dovetail has a piece of green tape on it to protect the glueing surface. I am not near and cannot say what the mysterious brown is.

Bandsaw, spokeshave, dragon rasps, sandpaper. The layout is every thing and next thread I will take the time to show it. I have 4 basic neck profiles I offer and have a system for hybridizing them. Next time.

To shape a neck by feel the FB virtually must be attached. And mine is. Inlay and fretting come after neck to body assembly. .

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Bruce Sexauer, luthier
http://mojoluthier.com

You do work incredible fast!

And is this your traditional oil based varnish too? I love the luster that has.

Holy cow, when you zoom, you really zoom!!!

Definitely would like to see your neck shaping process. I've spent way too long on carving my latest.

Thanks for sharing Bruce - beautiful in all respects. I will be following the finishing steps closely, as I am looking for new/better ways to finish my guitars. I am limited to hand applications, and plan on staying with French polish for tops. But the rest, I would like alternative finish method.

Glenn

Lately I am spending 10 hours a day in the shop, and this month it’s been 7 days a week as there is nowhere to go. Typically, my guitars use up about 150 of my hours apiece, but a large part of that is finish and set up. While oil varnish is in many ways an ideal finish, particularly where tonal performance is concerned, it is relatively time consuming. Both application and sanding are far more challenging than lacquer. Application because the line between too dry to flow out and so wet that it sags it very fine, and sanding because one must sand as completely as possible between each of about 8 applications and yet never sand through, which requires intense concentration. I seem to thrive 0n this kind of intensity however and wouldn’t have it any other way. Being in touch with each layer of finish in this way makes it a slam dunk to achieve seriously thin finishes with very consistent film thickness. I see people claim 5 mil lacquer finishes, yet the best I was ever able to do was 8 mil, and when I was into repair I found that 10 mil was the common rule. My finish is consistently around 3.5 mil measured on the belly when the varnish is stripped for the bridge, 5 mil being the most I’ve ever seen.

I have an email I send to people who ask me about my finish which details products and methods. I have up dated it a few times as I do continue to refine the process and product availability has changed considerably in the 50 years since I started developing my methods. When I get to my computer (on the iPad at breakfast just now) I will post it here.

_________________
Bruce Sexauer, luthier
http://mojoluthier.com

FYI: the last set of pictures is after sealer but before porefiller, and no varnish is yet involved.

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Bruce Sexauer, luthier
http://mojoluthier.com

Here's my latest info on my Varnish methods. Do not shy away from brushing if you don't have spraying together. But get a good 1 1/2" natural bristle brush. $20 to $50, generally.

Varnish Schedule as of 2019

I do not rely on the scraper so much as on abrasives to prepare to surface of my guitars for finish. I use Norton Adalox and favor the 2 3/4” wide PSA backed rolls. These are used with a variety of backing blocks I cut from flip-flop sandals I buy after the summer ends and they go on sale. The cheaper dead flat ones are the right choice. Notice they come in a variety of densities. The coarsest grit I use is 100, followed by 180 and 220. All endgrain, and often the guitar top, also get refined with 320/400 Norton SoftTouch, a foam backed abrasive pad.

Compressed air is used to blow the dust out of the pores, followed by a tack rag. Two coats of Zinnser SealCoat, very similar to shellac, are applied to seal the wood. This product greatly enhances the bond between the varnish and the guitar. It also largely keeps the color in the pore filler from staining the wood, and particularly from penetrating the end-grain excessively compared to the rest of the wood. The stuff dries adequately in about 2 hours. Clean up the surface with the 320/400 and the pore filler will make less of mess.

For a guitar, a full size spray gun is overkill, though it will work. At their scale a touch up gun works very well and give more control. While there are better guns than Harbor Freight sells, their $15 gun works surprisingly well. Their $35 gun works better, and that’s what I use for the SealCoat. If I do a burst, I put the color in the sealer, and that’s why the better gun for the sealer.

Solvent based pore filler seems to work the best for me. Pore-o-Pac is one, but they are all similar in my experience. I am currently using a Mohawk product. It colors well with artist’s oil paints. Burnt Sienna is good for mahogany, and burt Umber for Rosewood. In most cases, the filler should be darker than the wood or it draws the eye. Thin it with the recommended solvent to the consistency of heavy creme, and paint it on with a chip brush. Rub in in with a Blue shop towel and let it dry till if flashes off and looks dull. I use burlap salvaged from the local feed store to remove the bulk of the residue, aggressively wiping at a diagonal to the grain in the hope of removing as little as possible from the pores. I have found that repeating the pore fill process after an hour or so will save me at least one coat of varnish. That’s 10 minutes against 2 hours, so seems like a good idea. The can says to wait 24 hours before coating, but I have found 4 hours to be fine.

The next step is to carefully clean ALL of the profiler residue off the sealer surface. Again, I use the SoftTouch 320/400 for the task. Then I spray another coat or 2 of Zinnser SealCoat over the pore filled surface.

Two hours later the first coat of Oil Varnish can go on. If the surface is smooth, there seems to be no need to scuff the sealer. Currently, I am using 2 different varnishes, and mixing them together. One is the Ace Hardware Store in-house product: Gloss Interior solvent based Varnish Product 276A111 (ACE16389). Some stores say it doesn’t exist, but it does. The other product is technically a Urethane, and is made by Murdoch in Vermont. They call it Uralkyd-500 Floor finish (Gloss). It dries faster and harder than the Ace product, and mixing them seems to mix their qualities in direct proportion to their quantities. I find this useful in manipulating tone through controlling structure. The viscosity of the Ace product when fresh is about right, and can be maintained by adding small amounts of true turpentine. I also add about 10% by volume of acetone in the interest of getting a better bond between coat and avoiding witness lines.

One coat can be applied every 24 hours. It is extremely important to degloss each coat before applying the next. The ultimate goal is to have a mirror flat surface, but in the early coats deglossing is enough. You NEVER want to sand through to the wood, but if you do, reseal with the SealCoat.

I degloss the first 2 coats with the SoftTouch 320/400 without eliminating pores or low flaws.

The third coat I use a flip flop block and 320 PSA paper to achieve a flat surface, but still allow some pores to shine. They are how I know how far I’ve sanded. Before blocking the surface flat, I use CA glue to do any drop fills that may be required.

The fourth coat I sand with 800/1000 SoftTouch, and usually I am rid of 90% of the pores. If any deep flaws were missed in the first drop fill, get them now. Use a single edge razor blade as a scraper. Use only the center of the blade, wrapping a piece of cello tape tightly around the two end thirds of the blade to hold it off the surface, flexing the blade to get the center third down as needed. Any drop fill needs at least 2 coats of varnish over it.razor.jpg

If the surface now looks perfect, go on to the penultimate coat, but if not, repeat the fourth coat procedure. do this as many times as it takes. If the surface gets too far from flat, you may want to use a black and 320 dry paper again, but usually not.

The penultimate coat get sanded dead flat with a flip flop bock using 800 grit wet/dry paper.

Spray the final coat and put the guitar away for a few weeks to cure. While it can be rushed and done in a few days, the finish is much harder in 4 weeks and will look a lot better. Sand with a flip-flop block backing 1500 or 2000 grit wet/dry (wet!) paper. Buff to the desired gloss. I use a pedestal buffer with two wheels, one for brown pre-buff compound, and the other for Menzerna creme buff. Pretty standard stuff. Varnish is trickier to buff than Lacquer as it does not want to get hot at all.


Bruce Sexauer

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Bruce Sexauer, luthier
http://mojoluthier.com

Thank you for this extremely informative finishing schedule. Many great gems here. I suffer most trying to finish really well.
Now, if I could only see the rope binding(hog-tieing) in action. My wood binding always suffers exactly as described from insufficient tape clamping pressure. I have even tried the giant rubber bands. Never enough hands.

whoops, just deleted 10 minutes work. Here it is again, somewhat more concisely

The Rubber band is less than half way from the tape to the rope. The ideal rope is about 3/16" in diameter and has some stretch in it. Cloths-line works, so does old school parachute cord. Tradition Jute is what I learned on.

Here is what I mean by scuffing between coats. This is the first coat, and I use more care with it than subsequent coats. Don't even dream of making it flat, just degloss it.



The head end with pore filler and 2 coats of oil Varnish:



The truss rod nut:

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Bruce Sexauer, luthier
http://mojoluthier.com

Allow me to digress (if that's fair) to a design consideration. Why the sound port, for you personally? Lots of people do them, but I've never considered one, the way I wouldn't consider moving the sound hole. There's something about the traditional guitar body that I can't let go of.

I'd be very curious to understand how to came to the decision, and why you continue to do it.

Thanks in advance.

Everything about this model is intended for the player. While it will probably work just fine as a performance tool, that’s not what it’s about. So, the side port is for the player. I don’t make many guitars with them as I imagine people buy my relatively expensive guitars as the ultimate tool, but of course many don’t play out at all, and those who do often use PUs and all that entails. I believe there is no free lunch, especially is a radically limited energy system like an acoustic guitar, and I have observed a side port to hamper project to the back of the room quite noticeably, but that’s not what this guitar is intended to do.

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Bruce Sexauer, luthier
http://mojoluthier.com

Flip flops huh... I'll have to give that a try. I can see how that just might be a perfect hard yet soft enough block.

One of those 2' X2' standing mats (the kind that interlock) might also be a good source of material.

I can confirm that the work quite well. Cut scraps into useful size pieces and use 3m #90 to adhere the sandpaper

Flip flops are cheap, especially at the end of summer, and come in a variety of densities. Get the flat ones, of course. I have been using them as sanding blocks for many years. I buy Norton PSA paper on continuous rolls 2 3/4” wide. My source is H & H Supply in Circle Pines, MN. Use my name, they’ll know what to sell you. (763) 780-0964

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Bruce Sexauer, luthier
http://mojoluthier.com

Today I applied the 4th coat of varnish to CN#2, which account for about 2 hours. The rest of the time was spent inlaying and fretting the Bosnian Maple/Adirondack 000 I am making for Eric Schoenberg. Then I made a bridge and glued it on, followed by riding my bicycle for a couple of hours.
Here's a shot, more at another time if it's the least bit interesting. From my POV, the most interesting thing is that I used a fumed Pernambuco stain directly on the body wood, and go the MOST amazing color.

This usually means strings the following day:

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Bruce Sexauer, luthier
http://mojoluthier.com

Bruce, thanks for the detail on your finishing process.

I'm curious as to how you settled on the two particular varnishes (Ace and Uralkyd) that you blend together. Was it a process of experimentation that lead you to these two? If so, what varnishes didn't make the cut?

I’ve never met a commercial oil varnish that didn’t work as a guitar finish. They all handle much the same, though drying times vary, as does hardness. Spar varnish is generally to be avoided as too soft, the ideal being usually called interior or cabinet varnish. Always gloss not satin or semi gloss. I learned of my first varnish brand from others, but it went out of business long ago. Behlen “Rockhard” was good for a while, but they kept reformulating and it became a weird color. I used Ace straight from the can for many years but always thought it a bit soft. Another luthier recommended Murdoch, but it seems too hard. Mixing them blend their attributes wonderfully, and so far there has been no down side.

I have tried about a dozen different varnishes, 5 different waterbournes, innumerable nitro lacquers, and even CA glue using French polishing technique. For me, the current oil varnish is the best of class, giving me the closest to ideal results and being as pleasant as possible during the entire process. Because I am able to achieve such a thin coating, it is relatively vulnerable to impact damage, but makes up for this by being extremely abrasion resistant, and NEVER in my experience cracking up unless the wood itself fails.

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Bruce Sexauer, luthier
http://mojoluthier.com

If you were to brush instead of spray would you thin the varnishes differently?

Forgive my rookie question, but what are the fumes like with the varnish? I primarily work out of the basement of my house, and I've got my family around quite a bit. In my very limited experience I've appreciated the oil and waterborne lacquers I've been using because I can get some finish on an instrument, and ten minutes after I'm done if need be teach a guitar lesson in the same room.

I brush at a little higher viscosity than for spray. Hard to describe w/o demonstration. Ace is about right for brushing when the can is opened.

Oil Varnish is relatively healthy in the adjoining environment, but ventilation for a couple of hours is still advised. I thin with turpentine. I love the smell of it, but my wife does not. Good thing we don't live in the shop . . . anymore.

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Bruce Sexauer, luthier
http://mojoluthier.com

I was just on the Ace website - they don't have that product listed, Ace Hardware Store in-house product: Gloss Interior solvent based Varnish Product 276A111 (ACE16389). We have an Ace about 5 min away, I'll have to try at the store.

Is it possible to "pad" it on as well? I enjoy the control of French Polish technique. I have used Tru Oil, and just wipe that on, then off, wondering if same technique would work.

Thanks!

Glenn