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Private member DiscussionAcoustic Repair

Modular Clamp For Acoustic Guitar Repair

So, I made a modular clamp based on the split clamp idea. Started on a prototype about two months ago and finished it. What I was aiming for was a clamp that I could use on the BOTTOM of acoustic guitars as well as tops to clamp cracks, cleats, braces, patches etc. Especially a clamp that would access small openings like "F" holes, small sound holes etc. Essentially a way to get a clamp to areas not accessible to jacks, wedges etc.,…

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Ian Davlin
Really cool design !
Private member DiscussionGeneral

Gibson Model Identification

My son in law texted me the following pic of a Gibson he once played and would like to find one for sale. I have searched the web to no avail, so I thought the collective here would have someone that recognizes the model. I was told it was an sj200 but I can’t find any sj200s that look like this instrument. Thanks in advance, Tom

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Private member
Thank you vey much! Found one on reverb now that I know what to look for 😁
Private member DiscussionAcoustic Builds

Missing soundhole braces Gretsch 6021 Town&Country Rancher flattop acoustic

Technically this is a repair, but I thought there would be some crossover with building, so I posted here as well. A 1950s Gretsch Town & Country Rancher 6021 is missing the two braces on either side of the sound hole (see photo). Because this is such a wide instrument (17” lower bout), I’m thinking that installing those missing braces will help with the stability of the top in addition to repairing the cracked/loose ladder braces. The…

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Private member DiscussionAcoustic Repair

Missing soundhole braces Gretsch 6021 Town & Country Rancher flattop

A customer recently brought in a 1950s Gretsch Town & Country Rancher 6021. In addition to two main ladder braces being loose/cracked, it’s missing the two braces on either side of the sound hole (see photo). Because this is such a wide instrument (17” lower bout), I’m thinking that installing those missing braces will help with the stability of the top, which is pretty sunken right now. Does anyone have any photos or measurements of or…

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Private member
Yes, of course Ian. That’d be fantastic if Dan could take a look! Sorry for the late response, I wasn’t paying attention with the holidays 😆.
Ian Davlin DiscussionOhio Local Looths

February 28th 2026 Inaugural OHIO Chapter Get Together at Stewmac

@member @member Starting the discussion here to get the planning underway. I am presenting at Cremona next year, so I thought I would use the opportunity to do a dry run during this event. Topics - 1. Modeling and 3d Printing Simplified for Guitar Repair Barbarians. 2. Touching up Martin Mahogany. 3. Color and Material Theory Simplified for Guitar Repair Barbarians.

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Daniel Williams
I would definitely be interested. Make to post a time when you know that its going to happen.
Private member DiscussionNeck Reset Database

Kamouraska Classical 1979

This is a Kamouraska classical guitar, model 111, made in Canada in 1979. Internet information says it was made in La Patrie, Quebec, and later the line became La Patrie guitars. It looks like someone has been into this one before as the dovetail fit was poor, the gluing is very sloppy, and there are some rough chisel marks on the face of the heel. Note that if you drilled holes at the 13th fret you would miss the pocket by a few mm. Th…

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Ian Davlin
Outstanding ! Nice call outs !
Private member DiscussionAcoustic Repair

Warped x-brace on Gibson L-3

I watched the Guild F-20 video (https://dev2.loothgroup.com/groups/repair-and-restoration/forum/topic/cracker-x-braces-on-guild-f20/#post-60310) with great interest since I've been working on a Gibson L-3 with a similar problem. A little back story - The original repair request was to address a small pickguard crack on the sound hole side. After peeking inside, I saw 5 loose brace ends on the treble side. Still a pretty standard repair…

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Private member
That move of 3D printing the taper you want and running it through the sander to make a copy just blew my mind! Thanks for sharing Dave!
Private member DiscussionAcoustic Repair

Martin 0-16NY bridge dimensions

I need to replace the bridge on a Martin that previously suffered a bridge replacement with a big, unsanded, pre-made pyramid bridge. The 1960s 0-16NY models had a straight bridge rather than a pyramid. If anyone has access to one of these, could you please give me the dimensions of the original bridge?

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Private member
That is a huge help, thank you, Doug!
Private member DiscussionAcoustic Repair

Fretboard hump above fret #12

Is it a common problem for the fretboard on an acoustic to develop a hump around Fret #12 and higher, where the neck meets the body? If so, what is the cause, and is there something that can be done, or avoided, during the initial build process? I have two quality Zager brand guitars that both have the problem, with the problem being worse on the cheaper model. I am a newbie to fret dressing and lowering, so I first tried adjusting the…

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Private member
Thanks for a great answer. I am a retired sonar engineer, so your explanation makes perfect sense to me. I figured it had to be almost an endemic problem with acoustic guitars.Next question: Can you r…
Private member DiscussionTools and Jigs

The first tool to measure longitudinal neck torsion/twist - the LTwist® gauge

Dear looth community/colleagues around the world, During 2023/24 I have developed a digital gauge to measure so-called longitudinal twist of (bass) guitar necks: the LTwist® gauge. Just to be clear, this is about the "cork screw" type of deviation along the length of a neck, not the bow of a neck. I think there is no need to explain how a too severe neck twist can make it difficult or even impossible to set up a stringed instrument (guita…

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Private member Discussion3D Printing

Side dot guides.

Here is a super basic thing I just modeled and 3d printed. Small drill guides to place a 2mm hole directly centered in the side of a fretboard. I made a few sizes for different fretboard thicknesses. Seems simple but its a huge time saver.

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Private member
sure. Im not sure how to do that.
Private member DiscussionCAD/CAM

Modeling / improving on dovetail jig

I've seen the Elevate Luthierie jig, and it seems simple enough. One thing I don't like about their explanation video is the handwaving around "set the joint length where you want it"...feels like even with the jig, you have to do too much measuring to make it fit exactly (or within the tolerance you want) Given I can model well enough in Fusion and have a 3D printer, feels like a challenge to take on! As far as I can see, the jig is just…

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Private member
I completely designed a elevate style jig in fusion. And have 3d printed it. Its great! If you want the files let me know
Private member DiscussionCAD/CAM

F5 Modeling attempt.

This is a repost from the main feed so it is in the correct forum. The recent F5 CAD modeling video inspired me to take a stab at it. I use Fusion 360 and have already completed a full A5 model that I’m using to prepare a lot of parts for my CNC. The F5 top seems intimidating. I focused on modeling the scroll alone for now. I didn’t pay attention to following a plan, or having perfect dimensions, or getting the curves to look perfect th…

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Private member
This is looking really great. If you'd like to come on 3d club and talk about it, let me know. The next meeting is this coming Monday and we'll be talking more about the top modeling.
Private member DiscussionAcoustic Builds

Archtop f-hole placement: how precise?

I was finally able to model something like a Gibson L7 top plate! Now I'm trying to build my f-holes... My only reference is the Benedetto archtop book, where it puts a few rules of thumb about how the f-holes should be placed. My question is, how precise are we talking here? One of the rules of thumb is that the bridge intersects at the midway point of the f-holes. Does this imply that the f-holes are at a certain location on the plate,…

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Private member
Possibly answering my own question...given my current drawing, there is 11.157" from the f-hole point I chose to the end of the body. If you assume that's the 14th fret, it implies a 26" scale length…
Private member DiscussionNeck Reset Database

1980 Daion 12-string

Model is "The '80". Daion built some nice guitars in the 70's and 80's out of a small shop in Japan. Nice old all mahogany 12 string. It's my instrument so doing a bolt on conversion. Forget about trying to get the neck off one of these (apart from Kung Fu) - neck construction seems to be based on multiple dowels (a bit like some Japanese furniture I suppose)

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Private member DiscussionAcoustic Builds

Bending Crelicam Ebony

A client has asked me to build an acoustic guitar using crelicam ebony for the back and sides that he is getting form Stewmac. I have heard it's challenging to bend, and this will be an OM so the waist is pretty tight. Any thoughts or suggestions for bending these sides? I use a homemade bending machine modelled after LMI's latest design (may they rest in peace) and I have had good success bending rosewood, walnut, mahogany, and pau fer…

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Private member
See the Michael M and Michael B entries in the "Side Bending" thread below
Private member DiscussionElectric Repair

Bigsby B60 vs B70

I've got a Gretch G2420T with Bigsby B60 on my repair bench. When the customer plays, the strings are coming out of the saddles. We're thinking of replacing the B60 with a Bigsby B70 to increase the break angle over the saddles and bridge. Any concerns with that? I noticed the B70 is only on center block models. The G2420T is hollow body. Will the inside braces support the B70 enough?

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Ian Davlin
That B70 appears to have the roller out in front to keep the strings down. If it's in the financial cards, I'd think that could work. The question is whether the extra length is going to be weird.
Private member DiscussionGeneral

Neck Shim spreadsheet

First time here on the forums, not sure how often I'll check in, but thought this the best place to post it. Was playing with an idea proposed by Buck Van Laarhoven on a parametric model for bolt-on neck shims, and found the formulas I wrote up translated easily to Taylor and conventional acoustic neck joints so decided to add boxes for those as well. I'm not well versed in Google Sheets, but couldn't see a way to upload the file direct…

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Hey Dave Recommend you make a copy of the file to load up. Then your original Google sheet won't be altered by another user in the shared file. You can do that by going to file and click 'make a copy…