Author Topic: The Scroll Shop (Ed of H's Shop Thread)  (Read 19421 times)

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #465 on: August 26, 2023, 05:34:25 AM »
I appreciate the props Coz, but scatch-making a bridge is tricky business. I could (theoretically) carve one that would work, from a functional standpoint at least, but would never pass for an OEM bridge for this particular guitar. I just don't have the machine tooling for that kind of work.

I do think it's possible to repair it. I sought the advice of some Martin repair guys over at the UMGF... Brian Kimsey weighed-in downthread and kinda' validated what I had already thought of, and what Tony here in-part suggested too. Brian is super-thorough, highly-respected, and consequentially a very busy dude. There's there usual folks on there who can't accept that anyone else other than the holy trinity of guitar repair ought to be taking on a job like this. And one of the site mods who has some experience too. I got what I needed from the thread, now just trying to decide; do I void this guy's warranty and smoke that bridge off and do it myself, or take it back to the store and them ship it to the nearest authorized repair center for fixing?

Here's the expert advice- https://umgf.com/replacement-bridge-for-hd-28v-t227517.html
« Last Edit: August 26, 2023, 05:36:29 AM by edwardofhuncote »

pauldo

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #466 on: August 26, 2023, 05:53:01 AM »
Gregory, your adventures and remedies are always fascinating. 

Side bar questions popped into my head while reading through the UMFG posts.   Seems standard practice to use CA/ Super Glue.  Are they the same thing?   What brand do you use?  most importantly- Any tips and tricks on stopping the tube/ container from drying out?

Seems every time I get a tube/ bottle for a job, I get one or two uses out of it before the contents turn to stone.

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #467 on: August 26, 2023, 06:35:23 AM »
Superglue, Krazyglue, and a couple others are brand names of CyanoAcrylate glue, Paul. And yessir, its become commonplace in repair shops as well as in some steps of initial building of instruments anymore.

The product I use is an industrial grade CA glue that comes from... Santa Rosa, California. https://www.caglue.com I didn't shop it, or plan it thataway, just coincidence. I buy it locally from a woodworkers supply house, in three different viscosities; thin, thicker, and gel. I also keep a can of accelerant around to cure it instantly when necessary.

It's handy stuff, and will get you out of a tight spot, but will also get you into trouble. A messy, sticky, bunch of hard to clean up, trouble. Ask me how I know.  ::)


*to answer your question; don't let air get to it. And you can clean the tips with acetone. Or nail polish remover with high acetone content.
« Last Edit: August 26, 2023, 06:37:59 AM by edwardofhuncote »

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #468 on: September 04, 2023, 04:14:15 AM »
Funny, how things have a way of flipping... I've had to start limiting my time in the shop on purpose. Now that I have almost unlimited time to spend in there, it was becoming commonplace to be in there more and more, so I had to start looking at it from a business perspective and think of it in terms of how many 'bill-able hours' I spend in there. It's one thing to go up there and just chill out and hang out, think about things... another altogether when I am in there fixing stuff and technically being 'on the clock' for somebody. Which reminds me, I need to get a new battery for the clock.

And honestly, most of what I am working on isn't exciting at all, but I am still enjoying it. Much of what I get in are simple little jobs on moderate-to-low quality instruments that I can make playable in a couple-three hours at $40/hr. + parts and strings. Or I can do a killer setup on your electric guitar or bass for a flat bench fee and you send a set of whatever strings you like. I've gotten a bit of a reputation for being pretty good at specialized setups. Tell me what you want, and I'll park it there. And there is still a good bit of upright bass work that walks in.

I just had to draw a line, and decide... okay, I'll put in 5-6 hours today and lights-out. My hope is that this little test-run is educational enough that when I turn in the keys to the Water Plant next year, maybe I can just pick right back up, if that's what I want to do.

I'm working on that scary HD-28 later today. I have a backup plan if fixing this bridge doesn't work out.


*Here's a sweet little project that I am about to finish; 1916 Gibson A-model mandolin. It needed a refret. And the bridge was glued to the top, in the wrong place, backwards. The best things it had going for it, none of the classic symptoms that usually do these things in; no sinking top, sprung waist, split tailblock... none. Just poorly maintained. Not too bad for 107 years old though. 100% original condition here... all parts present.
« Last Edit: September 04, 2023, 04:25:30 AM by edwardofhuncote »

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #469 on: September 07, 2023, 12:27:51 PM »
I am about 97% done with the mandolin. The final 3% involves the last little tweaks to the action/setup, which I want to wait a few days on... now that it's been refretted and put under string tension. I just want to let everything acclimate, humidify, stabilize, then make whatever final adjustments that are needed. So far it has settled in very well.

I made a new bone nut for it. This is especially tricky on a mandolin; the strings are in pairs, tuned in unison. If one string slot is deeper than the other, the higher string will note sharper when fretted somewhere on the scale, than its coursed mate. This is critical stuff... these are hateful little things to keep tuned in the first place. To say nothing of how hard they are to play if you don't get the slots cut deep enough. It then becomes like playing an outta' tune egg-slicer. So I took my time, got the nut slots spaced, cut, and filed in. Got the original one-piece non-adjustable bridge refitted to the top, and left it a touch high, to account for any top sinkage that might occur. So far, that's been minimal.

After restringing, I fitted the old original pickguard with some new cork linings, and buckled it back in place. Check out the patent dates... July 4th, 1911 on the clasp, and Mar. 30th, '09 on the pickguard. Was the U.S. Patent Office open on Independence Day?


*evidently July 4th wasn't a paid Federal Holiday until 1938...

I'm conflicted on one last detail. A mid/late 19-teens A-model would have had a blank headstock when it left Kalamazoo. Often these would get a decal or sticker from a dealer or music store that sold them. If they made their way back to Gibson, they'd often be retrofit with a current logo, whatever was going. My 1919 has a white stencil Gibson script commonly seen on 1935-42 guitars. I have a set of "The Gibson" in MOP, (you can see it in one pic) and a more oft-seen in the 20's silver-stenciled applique of "The Gibson", much easier to do and less permanent. I could do either, or neither. I think it needs something up there.


On a personal note, and since we talk wood around here a lot... it's been really interesting to play and compare this little girl to my 1919 A-model in Sheraton brown. The major difference between them other than two years of age is the wood the sides and back are made of. Mine is maple, and this one is birch. Gibson didn't care, at least not enough to even put it in a spec sheet. They typically used maple for the upper-end models, because they got the nicer finish, but my little brown A-model has some quilt figure under that dark varnish. To my ear, the birch-bodied one still has plenty of treble-y sparkle, but a more woody bass. The maple one has a brighter, clearer everything, and projects more. They are night-n-day different, but still share that same thumpy commonality that oval-hole Gibsons all have.


It's been fun bringing this one back.
« Last Edit: September 07, 2023, 01:57:01 PM by edwardofhuncote »

David Houck

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #470 on: September 07, 2023, 01:46:09 PM »
Nice work!  Cool to see the two of them together.

cozmik_cowboy

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #471 on: September 07, 2023, 02:07:37 PM »
Sweet!  My dear friend Mick Scott had a 1917 A when I worked with that looked just like yours; one of the best-sounding mandos I've ever heard (though of course some of that was his fingers).

As to being a bear to keep in tune, I'm reminded of a folkie joke: 

How long does it take to tune a hammered dulcimer?

Nobody knows........

Peter
"Is not Hypnocracy no other than the aspiration to discover the meaning of Hypnocracy?  Have you heard the one about the yellow dog yet?"
St. Dilbert

"If I could explain it in prose, i wouldn't have had to write the song."
Robt. Hunter

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #472 on: September 07, 2023, 02:39:29 PM »
Often dating a Gibson is tough or impossible, for a number of reasons. This one though, made it easy. She has a Factory Order Number ink-stamped into the neck block. That tells when the batch of mandolins this particular A-model was a part of was in the manufacturing process. In this case, F-O-N 3635 was begun in 1916 according to Joe Spann's reference book. The Serial Number which is handwritten on the paper label, and glued in just before shipping tells us when it left the factory. In the case of #37103 here, the best guess based on a couple other known receipts in the Mandolin Archives, is early Spring, 1917.

My brown 1919 A-model has no legible F-O-N, and the Serial Number is late enough that I just assume Ol' Charlie is about 104 now. (namesake of the retired North Carolina State Trooper who I got it from, August 13th, 2010)

See, y'all... this numbers thing is deep-seated in me.  ;D

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #473 on: September 11, 2023, 01:03:58 PM »
I've been on strike for a couple days.  ;D

Nah, I was just stumped/frustrated with one, had to get away from it a while and start in fresh. This Martin HD-28. Ugh. I have high standards is all. I try to fix people's stuff as if it were mine. I would not want a repaired bridge on a guitar if a new one was an option at all. StewMac claimed to have one. I bought it. Nay... not even close to the correct replacement for this guitar. The bridge wings were too narrow and the pin holes were too far back. So it's going back. (their nqa return policy is great) I scrounged and found another source online for a bridge. It'll be here tomorrow.

But Friday... (sigh)... Friday was just not my day. Ever had one of those deals where you can't fall outta' the boat and hit water? Yeah. I knew it wasn't going to end well if I got hard-headed and stayed on the job, so I put that Martin in its case, cut the lights out and went in the house. Didn't come back up here until this morning.

I pulled it back out, got my heat lamp, deflector shield, seam knives, all ready, and started cooking that ebony chunk. Little by little, it started to let go. Almost two hours and a quart of coffee later the last bit of whatever goo they use finally released it. Here, ladies and gentlemen, is a big part of why this bridge was destined to fail; note the 3/16" border of finish around the bare wood footprint the bridge is supposed to be glued to. Alright, to be honest, I knew that I was going to find this... it's still irritatingly dumb for the maker of fine guitars to overlook something this basic. And in fairness to C.F. Martin & Co. they finally figured out it was dumb too, and corrected the issue.

So, Step 1 safely complete - bridge is removed. Once I've decided on replace or repair, I'll scribe around it and strip this extra finish so that whichever bridge goes back on will stick to the top.

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #474 on: September 13, 2023, 03:16:06 AM »
Another good morning for coffee and sawdust...

I finished up an upright bass setup yesterday evening, doing some final tweaks to the action this morning. I repaired and set this bass up in April, 2019 (it's actually way on back in the thread) The repairs have held just fine, but my customer wanted the bass set up for arco (bow-style) playing, and with ropecore, flatwound strings. They also needed the bridge to have a steeper arch. I maybe could have done it by shimming the bridge feet, and reshaping the crown, but we opted instead for a new adjustable bridge, and to keep the flatter profiled pizzicato bridge for a future reversion.

Fitting an adjustable bridge requires a couple extra steps... one foot at a time. I like to mark where the scale is on my hold-down tape, and a little reminder of the top of the soundpost as another reference point for the treble foot. I also like to leave the soundpost in while fitting a bridge. That tiny little bit of curvature in the top makes a difference.

Nothing really fancy about the rest of it. I still like to finish-sand bridges. I date them in the crotch, and initial them on the back. One extra note about this bass... I think the fingerboard is purpleheart. It isn't rosewood. It isn't walnut either. Whatever it is, it's deep reddish, and mildly flamed. The bass is Czechoslovakian-made.

*and my replacement bridge for the HD-28V came in yesterday's mail... it's rough, but it fits in all the critical dimensions. I have to jig up and rout the saddle slot longer (or do I?) here in a little bit, once I've had a couple thousand volts of caffeine...
« Last Edit: September 13, 2023, 03:44:31 AM by edwardofhuncote »

David Houck

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #475 on: September 13, 2023, 01:30:47 PM »
Nice bridgework!

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #476 on: September 14, 2023, 03:22:54 AM »
The upright bass left yesterday, freshly outfitted for arco play, and I took in another vintage Gibson mandolin project, this one for Fret Mill Music.

Gibson during the close of Great Depression, manufactured several budget lines of instruments that could be sold by places other than Gibson dealers. Catalogs like Sears-Roebuck or Montgomery-Ward, sold brand-names like "Oriole", or "Cromwell", you could buy a guitar that for all intents and purposes was an L-00, but said "Recording King" on the headstock, for a fraction of the price. Another of these house brands Gibson made was the namesake of their factorys' home; Kalamazoo, Michigan. There was a full line of "Kalamazoo" guitars, mandolins and banjos, even a mando-bass was available, practically identical to its Gibson counterpart, just... plain.

This one is a KM-11, a very simple mandolin loosely based on the Gibson 'Army-Navy' models of the late-30's/early-40's. They had flat tops and backs rather than more time-consuming carved plates, and with glued-in bracing, much like a miniature guitar. I think every one of the braces is loose in this one. I'll be taking the back off to gain the access needed to fix them. There's no binding on the back, just front bound on these. If I'm careful about the seam separation, it might be just an easy touch-up after the back is glued back on. Gluing the braces will be easy enough with the back off. I'll get into it next week.

I set up my saddle slot routing jig and tried a test-run on a sacrificial bridge. See... there's a fudge factor. The bearing tolerance of a Dremel tool just isn't meant for this kind of precision work. These saddle slots cannot have any slop whatsoever. I actually made this jig years ago, to clamp down to a guitar top, and correct a saddle slot on the bridge of a 70's Martin that notoriously intonated poorly. For this test, I have screwed a bridge to a block, screwed the block down to the bench, then clamped my routing shelf into place. I get it close with a ruler, then tap it with the fret hammer until the router bit traces the slot exactly. Set the depth of cut, mark the length of cut, annnnnnd, hit the switch. It takes an hour to jig up and ten seconds to do. It takes another 15 minutes to chill out. Longer if it goes wrong.

So I asked Ward... what rate do I charge for that?




edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #477 on: September 14, 2023, 08:24:36 AM »
In the repair of this HD-28, I have gone through Plans A, B, and C, and a couple offshoots from one of them. I bought no less than three bridges to replace the cracked original. Not a one of them would work. I did not discover that the last one would not work until late last night, when I was just about to glue it to the guitar. As a matter of habit, I always dry-clamp first, make sure all my cauls and clamps fit exactly right. When I slipped the new bridge down the two threaded rods in pin holes 1 & 6, they sprung outward. I had just wasted two hours modifying a bridge saddle slot and it turned out that the pinholes are drilled for 2-1/4" spacing, not the 2-1/8" spacing required. I said every dirty word I could string together, and went in the house.

I stewed about it well into the night. I could have made it work. It would have been even more work, AND, AND, AND, the outer strings would have fallen very close to the edge of the fingerboard up the neck. Mathematically it could have still worked with just adding 1/16" of an inch on either side. But then I got wallowed out holes in the bridgeplate to deal with. More swearing. Colorful, but less thoughtful or blasphemous.

So this morning a half-a-pot of bean-juice in, I  went back to Plan A, and just fixed the original. You'll have to forgive me not documenting the job... I just had to get it done. I pried the crack open, and flooded the slot, crack, and all with thin CA Glue, then clamped it down in both directions; front-to-back, and top-to-bottom. After that, it was a matter of clean-up, and polishing. Moment of truth came, and I tried the saddle in the slot - absolutely perfect fit. I had to tug it back out with my tiny Channelocks.

After that, Titebond and a twist of the Sloan bridge clamps. Plenty of squeeze-out. This dadgum Martin is going to leave here tomorrow, fixed. And here's the plus for my customer. If this thing cracks again, (and I don't think it will) they can still have it replaced under warranty.

Probably too early, but I am already doing a [happy-dance].
« Last Edit: September 14, 2023, 08:27:39 AM by edwardofhuncote »

edwardofhuncote

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #478 on: September 16, 2023, 05:44:40 AM »
There are some projects that I hate to see leaving, and others I am just kinda' lukewarm on, glad to get paid for and made somebody happy, but don't really miss 'em. And then there's that one... I can't wait to see it go. But in fairness to the guitar, it was some my fault, and a lot it's parent company. I was thwarted from the get-go, unable to get a suitable replacement part unbelievably not available from Martin, followed by three more online tries and fails, and still saved it.

It is a mighty good-sounding vintage-spec HD-28... that's all I got to say about that. I'm outta' here for the weekend. Kalamazoo mandolin disassembly on Monday morning.

David Houck

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Re: The Scroll Shop (Ed of H's Shop Thread)
« Reply #479 on: September 16, 2023, 06:10:35 AM »
Congrats; looks great!