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-   -   Nardan No.65 Late 50s Early 60s MIJ Archtop (https://www.acousticguitarforum.com/forums/showthread.php?t=557045)

Arumako 09-07-2019 08:50 AM

Nardan No.65 Late 50s Early 60s MIJ Archtop
 
Hello AGF,
Came across this unusual MIJ archtop project guitar. Looked through the archives here. Found very little information and wanted to share a bit about it. This is an MIJ, late 50s or early 60s Nardan No.65 archtop guitar.

https://live.staticflickr.com/6553/4...fd7c2ac2_o.jpg

Nardan was a subsidiary of Shinko Shyouji owned by Mr. Hatsuyoshi Iwata. Upon his return from Japan's failed occupation of Siberia, Mr. Iwata decided to invest his corporate assets into guitar building. Nardan specialized in archtop guitars and built many guitars for Teisco, Zenn-On, and Maruha Instruments.

https://live.staticflickr.com/65535/...74b991f87d.jpg

Apparently, guitars built for the local market were labeled "Nardan" and their exports to neighboring Asian nations were labeled "Nardau". The Nardan instrument company closed its guitar building operations in the 70s. Today, Nardan is operated by Mr. Iwata's grandson as a manufacturer of "Taishyo Koto" (miniature koto harps) in Nagoya. Their handcrafted archtop guitars are still highly sought after in Japan - the most popular model was the No.100 which was all solid wood and sold for 10,000JPY (approx. $1,000 today). They still pop-up on auction sites from time to time. This one is No.65 and is built with laminate back and sides and a solid spruce top. Probably sold for about 6,500JPY (approx. $650.00 today). Despite an inexpensive heritage, it's historical approbation at least demands a serious restoration assessment. Before disassembly, need to give her the once over. Six screws to keep the back connected to the neck block, hmmm...

https://live.staticflickr.com/65535/...de42117da0.jpg

Strange wavy construction (or destruction by dropping) of the butt-end of the guitar is causing misalignment of the tail piece

https://live.staticflickr.com/65535/...9183cc6154.jpg

Side cracks can be repaired with shims...

https://live.staticflickr.com/65535/...b27f821ab0.jpg

Nice bit of crushing near the butt-end - probably repairable...

https://live.staticflickr.com/65535/...96050a14ed.jpg

Now, how many tuning pegs should we try on? Fortunately, repairable...

https://live.staticflickr.com/65535/...fc3674e6b4.jpg

Okay well, let's take a look inside - off comes the back... The laminated back's arch is maintained with these curved ladder braces.

https://live.staticflickr.com/65535/...5699777293.jpg

Yikes, some one's been in here before. Found 3 different types of adhesives. The original rice-based adhesive typical for Japanese builds of this era...very very brittle stuff. Some clear yellow epoxy, and some brown stuff. The epoxy and the brown stuff were added later probably to reinforce areas where the original adhesive came loose.

The top construction is equally surprising. Japan in the 50s was a country struggling to rise out of her depression after losing the war. Furniture manufacturers and carpenters started making musical instruments with familiar adhesives. The rice-based adhesives became very brittle after just a few years of use; hence the cleat reinforcements all over the braces and the kerfing.

https://live.staticflickr.com/65535/...28093eb762.jpg

There's also a lot of kerfing failure along the top and back sides of this guitar. Will need to use shims here also.

https://live.staticflickr.com/65535/...2daeff7ebd.jpg

All-in-all a challenging, but not impossible restoration, I think. Hope to be sharing more as my journey unfolds. Probably going to be a long and slow restoration. Thanks for letting me share!

jricc 09-07-2019 12:13 PM

look forward to seeing your restoration!

mot 09-07-2019 01:41 PM

I enjoyed the pictures and story. I have a broken leg on a dining room chair which I am considering and your guitar pictures have made me lean toward gluing the break back together and then remaking and staining a new leg if that doesn't work out.

Arumako 10-06-2019 11:41 PM

Nardan No. 65 restoration
 
Thanks for the comments jricc and mot. After some serious consideration, I decided to dig into the restoration. While maintaining the basic structure of the instrument, there were three areas that needed attention; 1). Restoring structural integrity of basic components; 2). Replacing damaged components (kerfing); and 3). Removing excess (cleats and bracing).

After cleaning, the structural integrity of the back needed to be restored in several areas by pushing epoxy into compromised areas with a small spatula and clamping.

https://live.staticflickr.com/65535/...d5ff9901_b.jpg

The waist area of one side of the body cracked together with the kerfing requiring a re-shaping of the curve. An iron on low heat and a bit of water rolled over a coffee cup (with just the right dimensions) restored the arc. These laminated sides are very sensitive and laminated layers can pull apart with too much heat or moisture. Clamp and leave over night, and voila!

https://live.staticflickr.com/65535/...686f8679_c.jpg

Removed the cleats from the bracing and shaved the excess down. These guitars were built with exaggerated bracing heights and thicknesses (to maintain the arches in the top and back) that killed the overall resonance of the guitar.

https://live.staticflickr.com/65535/...e9498c56_c.jpg

The more the work progressed, the more obvious it became - the kerfing needed to be replaced. To ensure the shape of the guitar is not compromised, the kerfing needed to be replaced one section at a time. Here's half (right side in the pic) of the back-side kerfing removed.

https://live.staticflickr.com/65535/...d407d617_c.jpg

Because of the extremely fragile nature of the laminated sides, heat and water could not be used to remove the old kerfing. Had to use my trusty chisels to chip away at the old kerfing piece by piece. The new kerfing (maple) is wetted down for easy bending and clamped (but not glued) into place and left over night.

https://live.staticflickr.com/65535/...eaa338a5_c.jpg

Once the new kerfing dries, it is glued into place (titebond) and clamped. Because the laminated sides are very flexible (but dangerously brittle), a white extension bar is placed to ensure accuracy of length for proper fit during final assenbly. Interestingly enough the width did not need any reinforcement bar.

https://live.staticflickr.com/65535/...82a86df2_c.jpg

As of today, the kerfing for the bottom of the guitar has been replaced. The surface will need to be planed and sanded to match the back, and the same process will be applied to the top. The smaller structural issues are being resolved as the project moves forward. Still have a long way to go, but this will be converted to an acoustic/electric using K&K Twin Spot (for archtop) sensor pick-ups. Should get really interesting! Thanks for letting me share. Cheers!

mot 10-07-2019 07:33 AM

Thank you for the detailed update. Makes my broken chair leg look like child's play.

I had a broken violin years ago that I ended up trading for a working wooden clarinet. Your pictures make me wish I still had that violin to tinker with and try to bring back to life. The violin didn't actually have any broken parts. It had just sat so long in its case that the glue had broken down and the 100+ year old strings had pulled the top off. I think it was made somewhere in the northeastern US mainly because that's where I found it.

Wish I had pictures, but at the time I needed a clarinet more than a broken violin and jumped on the chance to ditch it.

Arumako 10-14-2019 11:02 PM

Kerfing Installed
 
Quote:

Originally Posted by mot (Post 6180673)
Thank you for the detailed update. Makes my broken chair leg look like child's play.

I had a broken violin years ago that I ended up trading for a working wooden clarinet. Your pictures make me wish I still had that violin to tinker with and try to bring back to life. The violin didn't actually have any broken parts. It had just sat so long in its case that the glue had broken down and the 100+ year old strings had pulled the top off. I think it was made somewhere in the northeastern US mainly because that's where I found it.

Wish I had pictures, but at the time I needed a clarinet more than a broken violin and jumped on the chance to ditch it.

Hi mot, Your violin sounds like it would've been an amazing project. 100+ years old, and all! I bet your clarinet made-up for it though. Wish I had the skills for brass or woodwind. My fingers seem to perform better than my lungs.

Was able to make a bit more progress with my archtop restoration. Installing new kerfing under the soundboard without taking the top off is somewhat of a challenging task. However, it's not impossible. Archtops with built in re-curves usually have flattened edges, but the sides of archtops like this Nardan are not flat, requiring the kerfing to match the undulations of the edges of the top. In addition, the edges of the kerfing need to be angled from about 3 to 7 degrees to fit flushly to the top. So, the new kerfing needs to be chiseled scrapped and sanded very carefully. In this particular case, the kerfing job was split into two stages to make fitting easier. Once the fit is verified, clamping the new kerfing is also a bit challenging...

https://live.staticflickr.com/65535/...574d1412_c.jpg

The larger clamps don't allow for necessary clamping space. The white bar acts as a support for bars cut to size from bamboo chopsticks (good flexing capabilities). The ends of the chopstick bars are grooved to push against the white cross bar and the clothespins on either side prevent the chopstick bars from slipping. It's also very important to make sure the kerfing doesn' start to slide up the sides.

https://live.staticflickr.com/65535/...c4e5c7d7_c.jpg

The kerfing job took precision and many hours, but here it is after both the top and bottom kerfings have been applied.

https://live.staticflickr.com/65535/...65058046_c.jpg

The bottom kerfing will need to be shaved and sanded to match the guitar's back, a much easier job when the matching back is completely off. Some areas under the braces need to be reinforced with adhesives, and side braces will need to be added. K&Ks Twin Spot acoustic pick-up will be installed before closing the box.

Adhesives will be applied to stabilize the neck joint. The frets will definitely be upgraded. Might install and resurface the fret board altogether. Clean-up the rear of the head stock. Clean-up and re-store lacquer finish. Install new bridge, saddle and nut. Still a long way to go, but making stable progress! Thanks for letting me share!

upsidedown 10-15-2019 08:53 AM

Thanks for sharing the story and repair as it progresses. I'm enjoying it and looking forward to any and all updates.

rockabilly69 10-15-2019 04:10 PM

Quote:

Originally Posted by Arumako (Post 6187023)
Hi mot, Your violin sounds like it would've been an amazing project. 100+ years old, and all! I bet your clarinet made-up for it though. Wish I had the skills for brass or woodwind. My fingers seem to perform better than my lungs.

Was able to make a bit more progress with my archtop restoration. Installing new kerfing under the soundboard without taking the top off is somewhat of a challenging task. However, it's not impossible. Archtops with built in re-curves usually have flattened edges, but the sides of archtops like this Nardan are not flat, requiring the kerfing to match the undulations of the edges of the top. In addition, the edges of the kerfing need to be angled from about 3 to 7 degrees to fit flushly to the top. So, the new kerfing needs to be chiseled scrapped and sanded very carefully. In this particular case, the kerfing job was split into two stages to make fitting easier. Once the fit is verified, clamping the new kerfing is also a bit challenging...

https://live.staticflickr.com/65535/...574d1412_c.jpg

The larger clamps don't allow for necessary clamping space. The white bar acts as a support for bars cut to size from bamboo chopsticks (good flexing capabilities). The ends of the chopstick bars are grooved to push against the white cross bar and the clothespins on either side prevent the chopstick bars from slipping. It's also very important to make sure the kerfing doesn' start to slide up the sides.

https://live.staticflickr.com/65535/...c4e5c7d7_c.jpg

The kerfing job took precision and many hours, but here it is after both the top and bottom kerfings have been applied.

https://live.staticflickr.com/65535/...65058046_c.jpg

The bottom kerfing will need to be shaved and sanded to match the guitar's back, a much easier job when the matching back is completely off. Some areas under the braces need to be reinforced with adhesives, and side braces will need to be added. K&Ks Twin Spot acoustic pick-up will be installed before closing the box.

Adhesives will be applied to stabilize the neck joint. The frets will definitely be upgraded. Might install and resurface the fret board altogether. Clean-up the rear of the head stock. Clean-up and re-store lacquer finish. Install new bridge, saddle and nut. Still a long way to go, but making stable progress! Thanks for letting me share!


This is a great thread to follow. You're doing a great job!

Arumako 11-01-2019 10:35 PM

Little Improvements
 
Thanks for the kind comments upsidedown and rockabilly69. Been making progress on small repairs and improvements here and there before closing the box and just wanted to post some updates accordingly as each of these small steps are pretty important to ensure overall functionality once the guitar is re-assembled.

As progress is made, I'm finding that both the previous repair attempts and (very uncharacteristic of Japanese builds of this era) the original build were less than admirable - perhaps built by an apprentice or a prototype? Certainly not representative of the craftsmanship inherent in typical Nardan builds.

First, the old adhesives holding the neck block and top needs to be freshened up. The joint needs to be cleaned up with thin strips of sand paper with backs reinforced by clear packing tape (if the sandpaper tears and leaves residue in the joint, adhesion will be severely compromised). With the guitar facing down, the neck is pushed down gently while glue is pushed in with a spatula and wiggled gently. Clamp down, once everything is set.

https://live.staticflickr.com/65535/...a17e566d_c.jpg

Re-gluing this while there is some flexibility in the overall assembly is important. The flexibility allows Titebond to move deeper into the joint to ensure a stronger bond. Once the side braces are installed the overall rigidity of the assembly won't allow for any wiggle.

The shape of the butt-end of the guitar was corrected when the old kerfing was removed, and this centered the tail block nicely. Of course, that means the tail piece position and strap button need to be re-positioned. The first order of business is to fill the old strap button. An old broken birch drumstick was cut and shaped like a dowel to fill the hole.

https://live.staticflickr.com/65535/...e96eb099_w.jpg https://live.staticflickr.com/65535/...6b754fab_w.jpg https://live.staticflickr.com/65535/...0feee29a_w.jpg

Once the glue dries the ends need to be filed/sanded down. Taking a file directly to the inside of the tail block is fine, but the outside needs to be covered with masking tape to ensure the finish is not scratched to oblivion.

https://live.staticflickr.com/65535/...f9ac699a_w.jpg https://live.staticflickr.com/65535/...50c03cd9_w.jpg https://live.staticflickr.com/65535/...36d36797_w.jpg

Decided to use K&K's Twin Spot passive transducer pickups. Although the output levels of these transducers leave a bit to be desired, the tone and voice are pure and can be shaped with a pre-amp or mixing board. I really like the simplicity of these units. The output jack acts as the strap button as well; so a new hole needs to be drilled in the center of the tail-block. A half-inch spade bit is used. It's nice when the back is off because the spade bit can be drilled from both sides to ensure no tear-out.

https://live.staticflickr.com/65535/...37ed4cbd_c.jpg

Just need to be really careful and drill slowly. The density of the birch drumstick dowel/filler and the actual tail block wood is so different. After drilling the center guide hole, I realized how soft the tail block wood was. In addition, it was probably too green when the guitar was built 50 years ago, and as the wood seasoned, the shape of the block changed significantly.

https://live.staticflickr.com/65535/...b7be16b4_c.jpg

Before final assembly, the back is positioned as a dry run, and the angle of kerfing is checked to ensure the fit is perfect. Imperfect areas are marked with pencil, the back removed, and kerfing filed down. This is repeated until the accuracy of the fit is verified.

https://live.staticflickr.com/65535/...28283737ea.jpg https://live.staticflickr.com/65535/...e9922a284a.jpg

Finally (for now), the bridge is shaped by fitting a piece of 120 grit sandpaper between the top and the bridge.

https://live.staticflickr.com/65535/...fd55f8b6_c.jpg

The bridge must be moved in exact parallel motion with the top to ensure the bottom of the bridge and the top meet flushly. Although it's simple, the process is quite time consuming. If the fit is not flush, full resonance will not be achieved. Here's another dry run to verify fit before everything is assembled.

https://live.staticflickr.com/65535/...ff73eea7_c.jpg

Still got a ways to go, but making steady progress. Thanks for letting me share AGF!

rockabilly69 11-09-2019 04:33 PM

Great to see this update! Can't wait to see this finished up.

rockabilly69 12-16-2019 03:42 PM

Any progress????

Arumako 09-13-2020 09:51 AM

A Very Little Progress
 
Gosh, it's hard to believe that this project has been on the shelf since November of last year! So much unprecedented things happening all over the place. I really hope everybody is staying safe and doing okay through this strange and unusual season in history. Things have been so very hectic; but I couldn't get rid of the itch to make a little progress on this project; so, I dusted off my work bench...

The easiest thing was to get the label glued back into place. I was originally going to replace the label by printing a new one; however, the original label peeled off quite nicely...completely dried out and brittle, but the back of the label was reinforced with a layer of plastic tape which was in-turn secured to the back with CA glue.

https://live.staticflickr.com/65535/...59e4cd88_w.jpg https://live.staticflickr.com/65535/...62448e71_w.jpg

For this project, I opted for the K&K Twin Spot piezo pick-up. Really excited to be using K&K products for the first time. Heard a lot of good things about them. The black bottle to the right is a bottle of dry Loctite which is applied to the threads of the output jack to ensure the screws don't loosen-up as the guitar is being played.

Everything is looking to be in good order. I should be able to glue the back into place next weekend. That will be followed by a re-radiusing of the fret board, installation of new frets, new fret board bindings, freshening up of the age-old lacquer finish, new tuning machines, final assembly and testing. Still a ways to go, but it's good to take a few steps forward! Stay safe everybody!

Mandobart 09-15-2020 05:10 PM

Thanks so much for not only the patience for this loving restoration but also for documenting and sharing it with us! I'll surely stay tuned!

Arumako 09-25-2020 08:29 PM

A Difficult Assembly
 
Thanks for the kind comment Mandobart!
Per my previous post, the time to close the box has come! For this application I decided to go with Titebond Genuine Hide Glue. A lot of folks have had mixed results with this stuff, but I've never had a problem before; so, grabbed a fresh bottle and tested the adhesive properties (just-in-case). With the original alignment and assembly being what it was, and my experience level being what it is, getting proper alignment for this project using normal procedures and tools was going to be challenging at best.

Additionally, the humid and cool local climate is a bit worrisome. Since the back fit was not naturally flush to the side, I decided to glue the back to the neck block first. This would ensure best alignment without resorting to building a custom mold. It'll also enable me to verify the reliability of the glue (it's a fresh new bottle, but I noticed the date was over 12-months old!). After gluing and clamping the back to the neck block, the assembly was cured for 72 hours. Now, I'm ready to continue...

https://live.staticflickr.com/65535/...b508518c_w.jpg https://live.staticflickr.com/65535/...ff4775df_w.jpg

Notice the gaping mouth at the butt end of the guitar. It's floating about 3cm. While the force required to keep the back adhered to the tail block is not enourmous, this will stress the glue quite a bit. Definitely will need extra working time and clamping time. To get the extra working time, the genuine hide glue is warmed to about 60 degrees C. This gives me an additional 10 minutes of work time, but the pay-off is longer clamping times.

The chopstick stick in the output jack weighed down with a 2 lbs. clamp is there to pull the butt end of the back into alignment by about 3mm. This will also stress the glue joint a bit. A hodge podge of clamping methods were used to ensure proper alignment.

https://live.staticflickr.com/65535/...3463e273_z.jpg

You can see how the alignment is off at the butt end of the guitar. This won't even be noticeable once I shave the back to match the sides and add binding.

https://live.staticflickr.com/65535/...23dac9fd_z.jpg

After 72 hours the clamps were removed and the tubing re-applied. The assembly will reman in this condition for one-week.

https://live.staticflickr.com/65535/...481c487a_z.jpg

Whew! Gotta run some errands, so...I think that's it for now. Hopefully, onto the neck and fret board next week! Man, I hope this thing stays together when the tubing is removed!

Arumako 09-27-2020 08:04 AM

A Break in the Weather
 
Had a surprisingly warm and dry day today, and the Titebond Hide Glue has cured really nicely. Still leaving the guitar wrapped in tubing, but was able to make a bit of progress on the neck by removing the frets. These frets are probably the original frets from the original build. I'm sure you all know this already, but I noticed the inconsistent position of the fret barbs. They aren't built into the wire but made by pounding the tang with a screw driver. Old school stuff...

https://live.staticflickr.com/65535/...4444d700_z.jpg

Used a soldering iron to heat the frets and they came out really clean. Oddly enough, this guitar's fingerboard was completely flat with no radius at all. Never heard of such a thing on an archtop. A nut end view of the fret board reveals an interesting laminated construction. A very thin (10th of a millimeter) rosewood veneer on top (hence no radius!) of a 1.5mm maple laminated with another 2mm layer below. No doubt measures to keep costs down.

https://live.staticflickr.com/65535/...6a3685ee_z.jpg https://live.staticflickr.com/65535/...ec7e44f7_z.jpg

Just for fun, thought I'd try to see what a 12" fret board radius would do. Thought there might be a chance of using the maple layer underneath the rosewood veneer. Achieved the 12" radius in the picture above; unfortunately, radiusing down to the maple will cut into the layer under the maple. The maple grain is discolored anyway, so the fret board is going to be swapped with a solid piece of rosewood. Debating whether to stay with the gypsy jazz style fret board marker at the 10th fret or to change to the standard 9th fret position...decisions, decisions! Great fun this is...

Mandobart 09-27-2020 10:22 AM

Thanks again for the updates!

Arumako 10-03-2020 06:15 AM

Binding Channels and Neck Prep
 
Thanks for commenting Mandobart. Starting to think this thread should be on the "Build and Repair" board... oh well, started here, guess I'll push forward to the finish unless an Administrator decides to move this thread... now that the box is closed, needed to cut the binding channels.

https://live.staticflickr.com/65535/...04c0190a_w.jpg https://live.staticflickr.com/65535/...917d8100_w.jpg https://live.staticflickr.com/65535/...8120185d_w.jpg

The Dremel Binding Channel Routing tool makes easy work of cutting the channels. Need to be careful to go slow and change directions to prevent tear-out. Super glued the bindings in and scraped the bindings down, filled cracks and tail piece screw holes. Now, onto the neck. The adhesives holding the fret board was extremely hard and no amount of heat on my spatula or the fret board would make it budge. Decided to cut-off the laminations first to see if a clean job could be salvaged.

https://live.staticflickr.com/65535/...4d43978f_w.jpg https://live.staticflickr.com/65535/...817b2f61_w.jpg

Was able to get a fairly clean removal of the fret board, but it's gonna take a lot of slow work to get the glue residue clean and flat. Should not have been, but was really surprised by the neck joint. The cut to make space for the dove joint on the top is quite messy. The neck joint doesn't fit well and is filled with the same old hardened glue that was used to secure the fret board onto the neck. For better or worse, this neck is never coming out of the neck block.

https://live.staticflickr.com/65535/...44652b06_w.jpg https://live.staticflickr.com/65535/...6c0271fe_w.jpg

After 5 painstaking hours, the neck is clean and flat. I read somewhere that these guitars had mahogany necks, but to my pleasant surprise, the neck is made from Japanese birch which is very similar to maple - very strong, and after 60 years, this neck will stay dead straight...

https://live.staticflickr.com/65535/...c721945b_w.jpg https://live.staticflickr.com/65535/...75bd82fa_w.jpg

Ending a really productive weekend by filling the many tuning peg holes on the back of the headstock. I really like using medium viscosity super glue for this type of work. The super glue naturally seeps slowly into the wood. Just keep filling the hole until the glue mounds up and let it dry. Wait 24 hours and take a sharp chisel to flatten out the mounds...

https://live.staticflickr.com/65535/...2d8d0aae_w.jpg https://live.staticflickr.com/65535/...5d30931a_w.jpg

Got the rosewood fret board on order as well as matching vintage tuning pegs. A lot of touch up paint and some lacquer re-coat to finish up. A bit more to go! Thanks for letting me share AGF!

rockabilly69 10-03-2020 02:01 PM

Great to see you're back at it and looking at the home stretch :) As always, great work you're doing! I can't wait to see how this turns out!

ArchtopLover 10-06-2020 02:52 PM

Quote:

Originally Posted by Arumako (Post 6201365)
The bridge must be moved in exact parallel motion with the top to ensure the bottom of the bridge and the top meet flushly. Although it's simple, the process is quite time consuming. If the fit is not flush, full resonance will not be achieved.

Really love reading this post. You got some serious skills :D.

Just a suggestion, have you considered using a jig/fixture to help when you profile your archtop bridge feet? I discovered this tool by Stew-Mac that is perfect for making sure that the foot is perfectly contoured, or as you say, "flushy" (and at a right angle) to match the sound board top.

http://https://www.stewmac.com/luthier-tools-and-supplies/tools-by-job/tools-for-bridges/archtop-bridge-fitting-jig.html

I crafted a home-made version out of 1/4" plexiglass and a left-over band-saw blade roller bearing, that works just as advertised, and it does make a huge difference in overall tone and volume to make sure the bridge foot contact, or foot print is perfect and "flushy" ;).

Arumako 10-07-2020 09:03 AM

Thanks for the comment and tip ArchtopLover. Actually, I was really having a hard time getting the bridge to sit perfectly on the arched top. No matter how much I sanded, the ends would be curled up ever so slightly, so I put the bridge aside for now. There's still plenty of material to work on the bottom side of the bridge; so like you, I'll definitely make my own copy of the jig when the time comes. Thanks again!

Arumako 10-18-2020 12:06 AM

Prepping the fret board
 
Had a chance to spend a bit more time prepping the fret board this weekend. Hope you all don't mind my sharing my progress. Sourced this beautiful 3A rosewood fingerboard from my supplier, and the first order of business was to flatten one of the sides. Really just a lot of sanding for this portion of the project.

My work bench is actually a round dining room table and while it's not a REAL carpenter's workbench it's folding sides really helps in my super cramped hackshop/office. It's also super flat and works perfectly for this kind of application. Been using this table for 15 years, but still need to measure for flatness just in-case there's any warping.

Double-stick tape some 220 grit metal sandpaper (more expensive than wood sandpaper but quicker work), and sand the bottom flat. After spending about an hour flattening the bottom, the fret board is rough cut and directly taped on to the flat table. Then it's radiused with 60 grit (wood) sandpaper using my 12" radiusing block.

https://live.staticflickr.com/65535/...1f220429_w.jpg https://live.staticflickr.com/65535/...351e5a3e_w.jpg

You can see the pitting in the fret board from the planing done at my suppliers shop. Some areas are pretty deep so this is going to be a long sanding process!

After some sanding the edges begin to take shape and the coloration clearly identify areas that need work. Each sanding stroke needs to cover the entire fret board. It's tempting to concentrate on the areas with more pitting, but that will throw the lengthwise flatness of the fret board off. Long, consistent, precise strokes combined with frequent lengthwise flatness verification is crucial.

https://live.staticflickr.com/65535/...ec05bb2a_w.jpg https://live.staticflickr.com/65535/...24f4f895_w.jpg

Cleaning the sandpaper frequently is also quite important. At first the paper only loads on the fringes; but once the paper starts loading all the way across as shown in the photo, I know I'm making consistent progress. Too much loading on the sandpaper may cause the wood to get gouged. As the sanding continues the beauty of the wood really begins to stand out. The nut end of the fret board is radiused just-right; but the sanding still needs to cover the entire length of the fret board.

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Just a little bit more to go... Man, this rosewood is just beautiful! The elimination of the discoloration indicates that the radiusing is complete. It's still a rough job up to this point, but it's important to verify the lengthwise flatness. Also, the radiusing sanding block is moved over the fretboard to ensure there's no light that seeps through at any point.

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After 2 hours or so, the rough radiusing is complete and the fret board is flat and straight. It sits on top of the neck with no gaps and the neck angle is perfect! YES!

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By rough radiusing the fret board, my fret slots can be cut with the same radius as the fret board. When the frets are installed, there's no gap between the bottom of the fret tang and the fretboard under the middle section of each fret. It all fits nicely with no need to use super glue as a filler. The old masters didn't even need to use glue to keep the frets in place!

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The fret board really is perfectly suited for a Japanese guitar of this vintage. I can't be more pleased! However, before installation, the fret slots need to be cut and the binding installed. To do this, I'll need to make a custom jig based on the shape of the flat side of the neck. Then finalize the fret board shape and fret slot depth, add binding, then finalize the fret board radius with 1000 grit sandpaper... then, I can glue the fret board onto the neck and continue from there...whew another productive weekend!

Just received the vintage tuning pegs (really hard to find!) that fit perfectly too! Woohoo! Thanks for letting me share AGF!

Arumako 11-01-2020 03:40 AM

Fretting over Fretboards and Other Minor Points
 
Hello AGF. Hope everybody is hanging in there. Things in my neck of the woods are relatively stable; and guitar project progress is slow but significant.

So, just as I settled on my rosewood fretboard, wouldn't you know that my supplier put some ebony up for sale at 50% off! One piece was pitted pretty badly, but had a beautiful lighter hue streaking through the fretboard length...of course, he offered a further discount and I just couldn't resist!

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Wasn't sure if the board would have enough thickness after radiusing, but it does (barely), and I'm really liking this. Ebony is much much harder to radius, but... I dunno... rosewood or ebony?

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Can't make up my mind, yet; so, needed to improve the area under the fretboard extension. The right shim (treble side) came off easily with a bit of heat. However, an unexpected crack in the sound board under the left shim made clean removal impossible. First, the cracked top and left shim needed to be glued back together using Titebond and clamped. Then the shim was removed with a sharp chisel instead of heat. The structural integrity of the area was verified and finished with some 600 grit sand paper.

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Of course, the area under the fretboard extension needs to be rebuilt; so some scrap from the ebony fretboard was used together with some old reclaimed Canadian birch hockey sticks. Years ago, a hockey enthusiast friend had some old sticks that were broken or unused, and gave the scraps to me. I really enjoy working with this wood and they are used sparingly in my projects whenever appropriate.

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Before the fretboard extension is finalized, the gap in the dovetail joint needed to be addressed. There's just enough room for a small file to clean inside. A piece of scrap Koa will be shaped and glued into the gap.

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On to the bridge...really wanted a bridge with a bone saddle, but couldn't find one with an ebony base. The bridge is a bit too light in color; so, some flat black nitro-cellulose lacquer was thinned to about 7 parts thinner and 3 parts paint. Rubbed clear thinner into the bridge, then proceeded to rub the bridge with the thinned out flat black lacquer. The lacquer seeps a bit into the rosewood and acts a bit like a stain. You can still tell it's rosewood, but the color is darker like...walnut. It will go well with either the rosewood or ebony fretboard.

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With a pressed arched top that's at least 50 years old, it's quite difficult to have a completely symmetric arch. The few cracks in the top also make it really difficult to match the top arch to the arch in the bottom of the bridge. I'll definitely need to use the tool that ArchtopLover talked about earlier in this thread; but for now, I needed to resort to the "sandpaper pull" trick to get the bridge flush to the top. It's still not perfect, but it's much much closer.

Only small steps of progress this weekend, but really pleased with where things are headed! Thanks for letting me share AGF! Stay safe everybody!

Mandobart 11-01-2020 06:18 AM

Wow! I've never put this much work into an instrument. I've just done some pickup installations, bridge and nut replacements, swapped out tuners etc.

Truly a labor of love that shows patience and skill! Thanks for sharing this project.

Arumako 11-03-2020 08:20 AM

Fretboard Extension Support
 
Thanks for the kind comment Mandobart. This restoration is thoroughly engaging for me. Hope it will be of some help to anybody else attempting restorations somewhere out there. Despite being inexpensive, a 50 year old solid spruce top, pressed or not, is hard to toss into the garbage!

The Koa neck block filler took awhile to shape. A lot of scraping and sanding, but in the end the shape came out pretty good. The extra length ensures the piece doesn't get stuck in the slot prematurely. It's not perfect, but it will do well enough. Some years ago, my mentor gave me a bunch of tools, and this Japanese hand planer is one of them. Called Titebond hide glue into service again and was really surprised with how much the neck block (not the Koa) soaked up the adhesive.

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Despite cool weather, the dry autumn in Japan allowed the glue to dry quickly. Taped up the body and sawed off the extra Koa. A sharp chisel and some Koa powder from previous builds with CA glue (to further fill any gaps) completed this part of the restoration.

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Now, it's time to turn my attention to the fretboard extension support. The Ebony/Canadian birch glue-up is looking really good. Turned to my Dremel Motosaw (scroll saw) to rough cut the neck cavity into the extension piece. The Motosaw is nice for general work, but it's not a good tool for final cuts and finishing cuts. Lots of chiseling, scraping, filing and sanding to get the piece into its final specs.

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The long Ebony scraps from my fretboard used in this glue up will be cut-off later. Leaving them in place gives me something to hold onto when shaping the piece, and they serve as nice alignment tools as well.

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Got the neck cavity in the fretboard extension support to fit nicely. Now, contouring the bottom of the fretboard extension support by hand is gonna be really hard. That'll be an all day project; so, gonna call it a day for now. Getting closer and closer!

Thanks for letting me share AGF! Praying that everyone will be safe and that the elections will proceed peacefully!

Arumako 11-14-2020 05:36 AM

Contouring the Fretboard Extension Support
 
Shaping the new fretboard extension support was as time consuming as expected.

It's really important to get the arch contour above the neck block correct. It's the area of the soundboard that has the most contact with extension support area and provides a solid footing. Rolling the pen along the inside diameter of the washer gives me a perfect mirror image of the contour. The tape is then fitted on to the extension support to ensure the piece is contoured accurately.

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Once the basic curve is carved into the sole of the extension support, the pattern is drawn into the sole with a pencil. In this particular case, minimizing the contact patch of the extension support and the soundboard is the goal. This extension is going to be contoured to allow for soundboard contact above the length of the neck block and two points at the forward tip of the extension support.

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Thanks to the Canadian Birch, the extension support can be really thin, and when combined with the Ebony fretboard, there will be plenty of stability even if the higher frets are played (a minimal issue for a non-cutaway archtop).

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After hours of routing, carving, filing, scraping and sanding, the extension support needs to be leveled and fitted.

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Just a little bit more to go for a final fit! Really excited to get to this point. Hope to be finalizing the fretboard with binding and fretting in the next two or three weeks and then on to final assembly and finish touch-up...

COVID-19 seems to be surging all over the world; so stay safe everybody! Thanks for letting me share!

Saxonbowman 11-20-2020 09:12 PM

Great thread! I love seeing how this goes together. Once itís done youíll forget how much work it was and how long it took. It will just be a wonderful guitar brought back to life.

ArchtopLover 11-23-2020 01:28 PM

Watching and Learning
 
Arumako, it's wonderful to watch this archtop restoration in progress. Your fretboard extension is just gorgeous. The attention to detail and the artful sculpture of the profile is quite lovely; too bad it will be hidden under the fretboard, where no one will see it, in all its glory.

I am curious, though, what was your reasoning for filling the small gap, or pocket, between the neck heel and the neck block? In your thread, you mention that "The cut to make space for the dove joint on the top is quite messy". Was it simply because the joinery appeared rough and unfinished, or was there another purpose, since the strength of the joint is mainly achieved by the fit of the dovetails?


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