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PostPosted: Sun Feb 07, 2021 3:29 pm 
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Walnut
Walnut

Joined: Fri Jan 15, 2021 7:20 pm
Posts: 9
Location: The Mountains
First name: Eric
Last Name: St. John
Focus: Repair
Status: Amateur
Hi. This is my first post. Please be kind; I'm just a drummer who loves guitar, who's broke and is learning to fix his own.
I've got three projects going on at once, but todays episode is about the crack repair I'm working on.
I did a LOT of utoob watching before attempting my first top crack repair, which turned out satisfactorily. (It was a double crack from the sound hole to the block end that originated from the two bolts that anchor a top-loading bridge.)
With confidence gained from that experience, I came across a "bargain" on Reverb. [Pause for effect.]
This is an early 90s Takamine with a solid spruce top. Its crack is about halfway down from center and runs from the "bridge area" at that level to the end.
What I've done: First, I hyper-humidified the guitar to close up the crack, which it appeared that it did. Then I used a window hanger suction cup to force glue into the crack. It never penetrated all the way through, though. After 24 hours under clamping, I cleated the bottom side using the ol' magnets trick.
What I see now: Previously, I could feel, and at the right angle, see where the repair was. Now, after a week, I notice that I can see down into the crack and the glue I trued to squeeze in there. I've bagged and put a few sopping wet rag bowls inside and it's now under my bed awaiting the next move, if any.
What I want to know: can I re-do this repair by steaming the crack apart again, then over-drying the top to open it up a little so I can try to squeeze glue back in? Or should I nix the idea of restoring this guitar altogether. Pretty sure I want to try a re-fret on it and upgrade the elex to make it my backup/ open mic/ camping guitar.
Thanks in advance! PS It doesn't look as if my photo is uploaded in the Preview...

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PostPosted: Mon Feb 08, 2021 10:20 am 
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Brazilian Rosewood
Brazilian Rosewood

Joined: Tue May 13, 2008 10:44 am
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Location: Virginia
You should bring the guitar up to a normal RH level but not over that. If it shuts tight in normal RH then you can get away with gluing it. In short that crack wants to stay open, you forced it closed by over humidifying it then glued it shut and now as you can see it is opening up again.

You cannot reglue a crack unless you used hide glue. It sounds like what that guitar needs instead is a splint. To do that you can take a razor saw and cut a saw kerf right down the crack line. This will also clean out the old glue(make sure that is the case). Then you need a sliver of spruce preferable of the same color and grain pattern and glue that in, scrape flush and refinish the area. Luthiers keep all their spruce cutoffs for this reason.

This is all conjecture on my part not being able to see the guitar but it's pretty common and early on in my repair career I have made the same mistake. Some cracks will simply not shut and over humidifying them shut will certainly fail.



These users thanked the author jfmckenna for the post: EricStJohn (Mon Feb 08, 2021 5:15 pm)
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PostPosted: Mon Feb 08, 2021 5:12 pm 
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Walnut
Walnut

Joined: Fri Jan 15, 2021 7:20 pm
Posts: 9
Location: The Mountains
First name: Eric
Last Name: St. John
Focus: Repair
Status: Amateur
Thanks, @jfmckenna for your input. The crack doesn't open completely, but just enough to pique my pickiness. In all probability, it was neglected before and after the incident that caused the injury. The seller said he'd had it 'repaired' "years ago". My guess is that the repairman simply humidified the crack shut because I can see no other evidence of such a repair. At present, it's not "rattling" or moving a great deal, especially since I cleated it. Perhaps I should just seal it with CA glue and do a complete refinish job on that confounded poly clear coat? Why do my photos not show up?

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PostPosted: Tue Feb 09, 2021 5:57 am 
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Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 12971
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
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Country: United States
Status: Professional
One's first post is forgivable being a drummer...... not so much :) Welcome Eric.

Our standard operating procedure for the hundreds of cracks that we have repaired over the years is to bag the instrument and take the RH up to around 75%. For us that's a large garbage bag with a car wash sponge with clean water in it. Never let any water touch the instrument and the sponge is in the bottom of the bag as the guitar with bag on it hangs vertically. The strings should either be removed or wrapped around the headstock out of the bag and RH.

We will bag and observe for up to several days at times.

Regarding normal RH and cracks. If the crack closed completely in that three day or less time we then let the instrument hang in our normal RH 45% for a couple of days. If the crack reopens or reopens very much we will fill it instead of forcing it closed and creating stresses elsewhere. Filling is a bigger deal and there are various methods and materials depending on a phrase that I will introduce you to in a moment.

I had a hernia repaired on the right side and sure as shootin I herniated in the exactly same place on the left side.... but I digress. Guitars are like this too, force something closed on one side and there may be newly induced stresses on the other side that may crack too.

There is an expression in the Professional Lutherie world called "appropriate for the instrument." Taking this into account and knowing what you are attempting to do cracks can be also filled and also cleated (glued across the crack with small diamond shaped pieces of spruce) open. If it's a beater it may be appropriate to consider filling or cleating open too.

Glue does not stick well to glue so that's why when we repair a crack we need to get it shut, level and uniform the first time.

And lastly when you are considering any refinishing you are well beyond the level of work that would ever be justifiable on this instrument for a professional shop or that most people would ever want to pay for as well.

Good luck to you Eric and again welcome to the OLF.

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These users thanked the author Hesh for the post (total 2): EricStJohn (Tue Feb 09, 2021 12:55 pm) • Pmaj7 (Tue Feb 09, 2021 11:12 am)
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PostPosted: Tue Feb 09, 2021 12:18 pm 
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Koa
Koa

Joined: Mon Feb 13, 2012 8:49 pm
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My opinion is to do the least-invasive technique to tend to the crack on that guitar ('appropriate for the instrument'). Ambient conditions, cleat the backside, mask off the top except at the crack itself and splint/scrape/ apply finish to the splint, and get back to playing. I think more contact begets more mess and the less we do the better.

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These users thanked the author phavriluk for the post: EricStJohn (Tue Feb 09, 2021 12:55 pm)
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PostPosted: Tue Feb 09, 2021 12:55 pm 
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Walnut
Walnut

Joined: Fri Jan 15, 2021 7:20 pm
Posts: 9
Location: The Mountains
First name: Eric
Last Name: St. John
Focus: Repair
Status: Amateur
@hesh Thanks for that input! That's the reason I'm consulting the pros! I knew upon purchase ($250 shipped from Reverb) that I'd need to do *some work on 'er. She's an early run of Takamine's G-series that's "half Pro Series and half G-series". Otherwise I wouldn't have bothered, @phavriluk Peter. What I've done thus far is "appropriate to the instrument." Anything else invasive will be done purely for experience. I doubt I'll try to splint it though. Prolly just fill, seal, polish, play...
I would like to address that lovely under-the-Polyurethane-finish milky fog that I've heard you get with abrupt and drastic temperature changes. And I mean it's bad. Nearly the whole back, a lot of the sides and top. The ovangkol shows much more than the spruce, of course. Like you guys have said, though, the value of my labor is for my satisfaction and not to enhance the value of the instrument.
Now I need to learn how to work my smarter-than-I phone's camera settings so I can share some pix with y'all.

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These users thanked the author EricStJohn for the post: Hesh (Wed Feb 10, 2021 6:38 am)
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PostPosted: Wed Feb 10, 2021 6:37 am 
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Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 12971
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
City: Ann Arbor
State: Michigan
Country: United States
Status: Professional
phavriluk wrote:
My opinion is to do the least-invasive technique to tend to the crack on that guitar ('appropriate for the instrument'). Ambient conditions, cleat the backside, mask off the top except at the crack itself and splint/scrape/ apply finish to the splint, and get back to playing. I think more contact begets more mess and the less we do the better.


And your opinion is correct Peter less is more in the professional repair world. I'm often at odds here with advice that would never be something that any quality, professional shop would attempt to do to and on the valuable personal property of someone else. If they did they may not be in business very long.

Minimalism, less is more, appropriate for the instrument are all views and approaches that save the arses of skilled repair people every day. I was gratified to see you post this you made my day!

Thank You.

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PostPosted: Wed Feb 10, 2021 6:44 am 
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Old Growth Brazilian Rosewood
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Joined: Fri Nov 02, 2007 9:49 am
Posts: 12971
Location: Ann Arbor, Michigan
First name: Hesh
Last Name: Breakstone
City: Ann Arbor
State: Michigan
Country: United States
Status: Professional
EricStJohn wrote:
@hesh Thanks for that input! That's the reason I'm consulting the pros! I knew upon purchase ($250 shipped from Reverb) that I'd need to do *some work on 'er. She's an early run of Takamine's G-series that's "half Pro Series and half G-series". Otherwise I wouldn't have bothered, @phavriluk Peter. What I've done thus far is "appropriate to the instrument." Anything else invasive will be done purely for experience. I doubt I'll try to splint it though. Prolly just fill, seal, polish, play...
I would like to address that lovely under-the-Polyurethane-finish milky fog that I've heard you get with abrupt and drastic temperature changes. And I mean it's bad. Nearly the whole back, a lot of the sides and top. The ovangkol shows much more than the spruce, of course. Like you guys have said, though, the value of my labor is for my satisfaction and not to enhance the value of the instrument.
Now I need to learn how to work my smarter-than-I phone's camera settings so I can share some pix with y'all.


Eric you are very welcome and I hope that something here is helpful to you.

That foggy, milky stuff you see under the finish is called blushing and it's a tell tale that the instrument was either finished in RH that was too high and/or the materials were still too wet and not acclimated to a suitable RH at the time of the finishing.

What can be done about?

Sadly nothing the only remedy is overkill and then some that is a complete refinish of all affected areas.

Taks are known for this by the way we've seen it many times on Taks and they are often sold disclosing the blushing in advance since someone would likely send it back if it was a surprise.

Lastly stripping poly is not something that our shop would ever get involved in but on the few occasions when we have done it for friends and on a neck for a famous bass player who played with Miles Davis and is one of our regulars we scraped it off and it was a night mare to do in terms of how long it took.

You know though at the end of the day scratched or instruments with cosmetic issues are still people too :) and some great playing can be done on them when we simply accept that things are as they are.

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These users thanked the author Hesh for the post (total 2): EricStJohn (Fri Feb 12, 2021 1:08 pm) • Pmaj7 (Wed Feb 10, 2021 10:57 am)
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PostPosted: Fri Feb 12, 2021 1:08 pm 
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Walnut
Walnut

Joined: Fri Jan 15, 2021 7:20 pm
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Location: The Mountains
First name: Eric
Last Name: St. John
Focus: Repair
Status: Amateur
"You know though at the end of the day scratched or instruments with cosmetic issues are still people too :) and some great playing can be done on them when we simply accept that things are as they are."
That's so true, @hesh ! This Tak is rough looking but plays very nicely and sounds great. I just did a level and crowning and ignored that blushing. That crack, though... I'm conjuring up the courage to razor saw and splint it like described above. I imagine that it shrunk back after being hyper-humidified and the glue I thought I'd squeezed in there while it was closed up actually didn't get in there after all. I can slide a .002" feeler gauge in there smoothly. I need to get my cleat out of there somehow without ripping the underside of the soundborard! I actually though about dribbling a little water above the cleat and putting a towel and steam iron over it. (But I've been told that steam is not the friend of a guitar.) I've noticed that even when I don't buy $tewMa¢ tools the expense is mounting. I've also been told that proper tools are an investment whereas improper ones are an expense LOL

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PostPosted: Fri Feb 12, 2021 3:08 pm 
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Koa
Koa

Joined: Mon Feb 13, 2012 8:49 pm
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First name: peter
Last Name: havriluk
City: granby
State: ct
Zip/Postal Code: 06035
Country: usa
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Status: Amateur
Back to fix what you see, and don't add to the problem with more moisture. Remember 'The Sorcerer's Apprentice' cartoon.

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PostPosted: Sun Feb 14, 2021 7:02 pm 
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Walnut
Walnut

Joined: Fri Jan 15, 2021 7:20 pm
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Location: The Mountains
First name: Eric
Last Name: St. John
Focus: Repair
Status: Amateur
phavriluk wrote:
Back to fix what you see, and don't add to the problem with more moisture. Remember 'The Sorcerer's Apprentice' cartoon.

Yeah, I agree. The musical term, "less is more," applies to instruments too! I want to thank you guys again for being so helpful. I learned how to build my computer by pestering the guys on the threads so... LOL beehive
I did, however, manage to "start over," so to speak: I have a tiny travel iron that fits inside perfectly, so I removed my cleat from maybe a week ago. At the time I write this, it's 45% RH in this room. Roughly 65 degrees. The patient is on the stand next to me, no strings attached [clap] and waiting for my next move. I was tempted to give her a spin after the fret dressing but decided not to put tension on the top until I figured out how to salvage this otherwise nice guitar.
I'm looking on evil bay for a razor saw but seeing nothing I had envisioned, whatever that may be.
One was around .010" wide, I think, and the crack can now receive my .011" feeler gauge. eek
I have a hand planer I figured could peel off a slice of spruce to fit in that pesky crack.
So far as Utoob goes, I haven't seen any "splinting" videos. Mostly of glue, clamp and cleat. (I like the strong magnet cleat holder trick personally.)
To that point, this is a NEX body/ size guitar. For the non Takadudes, that's their "mini jumbo" pretty much a Dred-ish/OM/Folk-ish size, I figure.
Anyway, my belt clamp didn't really get the bite I'd have preferred first time around. But the blessing in disguise is, because of my super humidity treatment that shut the crack at first, my glue never penetrated to where it could hold it closed and potentially do more harm than good like you guys told me. And the added blessing is that my cleat didn't do some real damage before I caught my error and removed it (fairly painlessly).

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PostPosted: Tue Feb 16, 2021 2:15 pm 
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Koa
Koa

Joined: Sun Apr 25, 2010 4:46 pm
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First name: Mark
Last Name: McLean
City: Sydney
State: New South Wales
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Eric, the usual reason why pictures won't load is that the file is too big. You need to take the picture from your phone into some sort of editing software, crop it and then resize it so that the final file size is under 256k



These users thanked the author Mark Mc for the post: EricStJohn (Wed Feb 17, 2021 11:37 am)
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PostPosted: Wed Feb 17, 2021 11:39 am 
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Walnut
Walnut

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Yup. But for future posts, I'll try to set the image size in my phone. If I can LOL

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PostPosted: Wed Feb 17, 2021 3:36 pm 
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Walnut
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Should I start a new thread to learn how to properly splint my top? I'm imaginative enough, though. Finding the right board to make such a splint may be a chore. That good ol' book that some folks swear by says that putting a new patch on an old garment isn't good because the old material will continue on its path while the new material is years behind in shrinkage and fading and such. That's paraphrased, but y'all understand.

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PostPosted: Wed Feb 17, 2021 4:17 pm 
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Koa
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I think any sliver of wood whose color is vaguely like the top's is going to work just fine. Overthinking begets analysis paralysis.

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These users thanked the author phavriluk for the post: EricStJohn (Thu Feb 18, 2021 12:16 am)
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PostPosted: Thu Feb 18, 2021 12:16 am 
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Walnut
Walnut

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First name: Eric
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phavriluk wrote:
Overthinking begets analysis paralysis.

[headinwall] That's sage, Peter. Truth.

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