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Transcript lightly edited for readability — filler and crosstalk trimmed, tool and proper-name spellings corrected. Speaker attributions added where clear.
00:07 — Q1. Tinting shellac with TransTint
Ian: Question one is a follow-up from John Layman on this guitar that had the crazy finish. He did some spelunking with denatured alcohol. John, what am I looking at — is this your test area?
John Layman: I went through the solvents and the denatured alcohol just dissolves it — it's like French polishing. I'm working through a lot of paper towels, but it's taking all of the alligatoring off. It must be some kind of shellac. There's a clean patch on the top and the back now.
Doug Proper: Just so you know, you're basically removing the finish on the top there. The back looks nice.
John Layman: The finish is going everywhere but the stain is remaining. I'm presuming it's shellac and I can French-polish it back up. Can I put this orange TransTint dye in shellac?
Doug Proper: You can dye shellac with TransTint — it'll accept it just fine.
John Layman: I want to get it back to the tone that's under the bridge.
01:58 — Doug Proper: Be careful if you're trying to spot-repair that area.
John Layman: No, I'm going to take the whole top off.
Doug Proper: So you're going to strip the top down, then re-French-polish to get back to a uniform amber. Doing it uniformly with standard French-polish technique on tinted shellac, you start a little on the lighter side, and as you continue to polish over it, it gets darker and darker. Stay as uniform as you can as you spread the colored shellac so you don't wind up with dark and light patches. When you're satisfied with the color, switch over to untinted shellac to finish. Spot-tinting is hard — as you French-polish a small area you'll wind up with a halo or a ring.
John Layman: I was delighted to find out it was shellac and not something more complicated.
03:48 — Doug: There are different colors of shellac — clear, amber, all the way to ruby red, and the darker colors will go on deeper. But if you're looking for that deep orange, I'd go with a dye. The orange is the right tint for this.
04:51 — Q2. Luthier Tool's neck-angle jig
Ian: Is anyone using the Luthier Tool neck-angle jig? The question is about setting up to cut the tenon and getting the correct angle dialed for cutting the heel block. It's the Luthier Tool one out of Kettle Falls, Washington. Brock, you know this tool?
Brock: Yeah, I've used it. It's pretty straightforward — you have to put your brain around it and go through the instructions carefully, but once it's set up it's straightforward. You get the whole body lined up on center, cut your mortise, then cut the tenon on the neck the same way. Then you put the body upside down on the jig and it measures your height, so you get the neck angle correct right out of the chute. It takes very little flossing once you've gone through it.
06:37 — Ian: Luthier Tool is out of business now — we're talking to them about bringing some of those tools back, getting that stuff over at StewMac.
06:55 — Q3. Fret glue: CA, fish glue, or none
Ian: Fret glue, from John. He asks what the group does — no glue, thin CA wicked in, slot fill, medium CA, accelerator, aliphatic. What do folks use, dislike, and why? Do you do it differently bound versus unbound? Does it matter acoustically if the frets are glued in?
Ian: It's a big subject. Who here hasn't put in frets every single way — no glue, hide glue, Titebond, CA, epoxy?
Doug Proper: I've tried pretty much everything and finally concluded that glue is unnecessary when it comes to putting frets in. I don't generally glue when I'm fretting. I'm not above it and I'm not against it — especially on a guitar that's been refretted many times and has fret slots that look like a country road, glue can serve a purpose. But I prefer to recut the slot and carefully match the size of the tang to the slot so I have a strong mechanical fit. If I don't have high confidence in the fingerboard wood, I'll wick a little CA in just to harden the fret-slot wall. The fact is, no glue on the planet will actually hold onto metal if it wants to come out of the slot — hide glue, Titebond, fish glue, CA, almost anything. So glue won't do the job of holding the fret in if it's going to come out by other means. The only justification I can think of for glue in a fret slot is to take up the extra air space — in theory for better tone, or so you don't get a dead-sounding note under a fret. My preference has pushed me away from glue toward stocking as many different fret wires as I need to match the tang to the slot, rather than hoping the glue takes up the extra space.
10:16 — Ian: James Roadman, are you a glue guy?
James Roadman: I don't always do it the same, but I agree with Doug — it's not a substitute for a properly prepared fret slot. I do sometimes put fish glue in on the theory that it's filling and solidifying gaps or the end grain, but I'm careful to make sure my frets fit well. Sometimes I don't use anything at all if the slots are new, and sometimes I'll wick CA in from the side.
11:00 — Ian: It's been some time since I've done frets, but I was using fish glue on just about all fret jobs toward the end — the idea being it was swelling the wood up over the barb, giving it that little bit more. But to Doug's point, take any adhesive in your playbook, put a fret on a piece of scrap wood and see how well it sticks. It does not stick. I used Titebond in my younger days, but it's messy. If you do use a water-based glue for that swelling effect, a tip I picked up from Eric Coleman on a StewMac video is to clamp your frets under a radius beam overnight and don't do any leveling until the morning. And watch the heat when you're crowning if you've used glue — getting frets real hot while crowning is probably not a great idea.
13:00 — James Roadman: If you're using a water-based glue, you probably want to let it sit a good while — you're swelling those slots, so let it dry in a way you don't have to with CA.
13:23 — Doug Proper: Your supposition about water-based glue swelling the fingerboard always seemed counterintuitive to me — you spend all that time leveling the board, then swell every inch or so with water and you're asking for an uneven fingerboard as the water saturates and exits the glue. Generally, cyanoacrylate won't swell wood. I only use it sparingly — I won't even wick it in much, just a little on a plastic toothpick run across the frets I'm worried about. My only purpose is to harden the fret-slot wall, not to fill voids — I'd rather all the airspace be taken up by as much of the fret as possible.
14:53 — [Panelist, Colorado]: From dry Colorado: the amount of instruments that come here, factory-made or luthier-built, if they don't have glued frets they're most likely coming loose, because boards move a lot even with your best humidity efforts. I use thin CA — it's more about hardening the grab of the wood itself, not expecting actual adhesion between metal and end grain, just a stiffening to keep the frets in. In an ideal situation it's just the fit, but there's enough movement even with good winter humidity out here. We humidify for the box, not the neck — the neck's a bigger piece of wood and it's going to move. Where you are in the world plays a role.
16:01 — Ian: It's actually not that different from Colorado here. We have ridiculously cold, dry winters — average about 17 degrees in New York all winter, under 15–20% humidity in any unhumidified space. That's enough to fold a guitar too. The problem in the Northeast is really wet, warm summers and then cold, dry winters — that acceleration from one extreme to the other, year after year, is what kills guitars where we live. But I've always approached it by making sure the fret slot is filled with the tang, and not expecting the barb to do anything but dig into the slot walls. That's also why I overbend frets, so when they flatten out the ends go down and things stay seated.
17:24 — Brock: One tip on CA: paste wax works pretty well if you're wicking from the outside in. And if it bites anyway, Alex Glasser showed me that a Q-tip and very light acetone will get superglue off ebony and rosewood boards pretty readily.
18:04 — Q4. Tracking builds & repairs: software vs paper
Ian: From Mo Guitars: he's been using a tool called Luth Tools, built specifically for luthier and repair tickets — Samar Bradley's app, link's in there. He got tired of managing spreadsheets and wanted something simpler and more automated. So the question: how do you keep track of your builds and repairs? Doug, I know you use paper tickets and spreadsheets.
Doug Proper: We use paper tickets, but they're all based on QuickBooks. We use QuickBooks as our financial software and our customer contact, and we track each job through it. Once a guitar's in the shop, the work order is a traveler that goes with the guitar. I know there's lots of cool software out there to track jobs — I've never used any. We tried computerized spreadsheets and other things over the years; I never got into the workflow stuff. As a shameless plug: in June we're doing a Loothing for Dollars episode on this subject, with people showcasing different pieces of software. But I've always just used QuickBooks for the organizational part, and then once it's in the shop it's whiteboards and many lists.
20:12 — Ian: Max, you might have maybe three builds in progress at the same time — do you have to bring software in to keep track?
Max Monterosso: Not really. Once I have the order finalized — which is also a spreadsheet that populates with options and prices with the client — I just save a copy with all the specs, and whenever in doubt I look at that. Sometimes I even print it out.
20:44 — Ian: James Roadman, have you brought software to bear on keeping track of instruments?
James Roadman: I've actually started using a program I coded with Claude, using Notion as the database backend for storage — so it's customized to what I want. I'd say it's a cautionary tale: once you go down that road it's endless tweaking, and if anything goes wrong you have to stop and figure out what's going on. It's not plug-and-play, but if you want to explore and really tweak your workflow, it's an interesting way to approach it.
21:46 — Ian: The thing about that approach: with every software-development project, developers have to throw everything at it to cover as many scenarios as possible, and you've only got a small batch of scenarios for your own shop — so you go into a package and have to learn all the stuff you've got to ignore to find the few things you'll use. What I'm finding with the develop-your-own model is you can build up from scratch just what you need and dial it in completely for yourself. We'll probably do a bit on building your own software at some point — I think Buck and Luke are both working on a kind of DIY shop-flow open-source project. We'd talked about possibly doing a 3D Club on that, as an extension of the AI-code-building conversation from a couple episodes back. If you're curious about AI, reach out to people who are into it — it's really approachable, not as scary as it feels, and it can do a lot more than get you out of writing a spicy email to a customer. It's getting very capable on the code end.
23:47 — Doug Proper: One observation on tracking work through a shop: make sure your motivations point toward the right end. I've seen lots of people promoting bells and whistles — software that sends customers pictures of the guitar in process, where it's at in the shop, spec updates in real time. I can't think of a good reason anybody would want to do that with a customer, because you're changing the motivation away from actually getting work done. The whole idea behind shop productivity is moving work through the shop, not sitting behind a computer sending customers pictures. It's not social media. Unless you can figure out how to get paid for it — if you're developing some kind of repair-concierge service where you're gift-wrapping the event of getting a guitar repaired, then you'd better figure out how to get paid for it. From my understanding we're already having a hard time getting paid just for the repair.
25:38 — Q5. Epiphone "ski jump": a forward-pitching neck
Ian: Corey's question — Epiphone ski jump. "I have a Kalamazoo-made Epiphone with the most extreme fingerboard ramp I've seen. The neck is dead straight from the first fret to the body joint, and I get about 1/16" of gap when I run the straight edge from the first to the last fret. The fret height averages .040", but someone leveled the extension — those frets are half the height. Any suggestions for flattening the extension?" Corey, are you still here?
Corey: I am, yeah.
Doug Proper: One thing that's suspicious to me — stick a light inside and see the condition of the top and the neck block, whether the neck block is moving at all. Did you look at that?
Corey: No, I didn't.
26:40 — Doug: Is this an old Emperor or newer?
Corey: Made in the '80s, I think.
28:10 — Doug: Is there any evidence in the top of checks along the edge of the fingerboard, anything that would suggest the neck block is shifting?
Corey: No — no disruption in the finish, no ripples, and the block looks pretty intact. There's no gap underneath the foot either.
28:48 — Corey: I just didn't know if anyone had had success flattening it in conjunction with refretting it.
Doug Proper: Have you put a straight edge or relief gauge from the nut to the body joint? You said that section is perfectly straight, and all the rise happens from the body joint up. When you sight down the neck, do you see almost a hinge at the body joint?
Corey: Exactly.
29:40 — Doug: What I suspect is happening is the neck angle has changed — very likely from the arch of the back getting longer. A lot of people don't realize that in most guitars with a steep, parabolic arch in the back, if that arch flattens out at all, by definition the curve gets longer. If it gets longer at all, it pushes the back of the heel up — it's got nowhere else to go, just distending the sides a little, even a few thousandths. That causes the neck to come forward, and it reveals itself as a fingerboard extension that looks like it's kicking up, but it's actually forward. That happens to tons of archtops over the years. The easiest way to get rid of it is to pull the frets and plane the incline out of the extension — hopefully you've got enough board to deal with it. Have you measured the differential between where the neck sits and the rise? You can measure in thousandths to project how much to take off at the end.
31:18 — Corey: Without taking the fret-height difference into account, it's about a 32nd of an inch of kick-up by the last fret. I measured with my Proper relief gauge.
Doug Proper: With the neck true and the relief gauge sitting at the body joint, move the outer leg and you can read exactly how many thousandths of kick you have by the tail of the fret. A 32nd is about .031". If your board's about 3/16" thick, .031" isn't going to make it too thin up there.
33:05 — Corey: The other thing is the fret height, since someone leveled these — that'd be another .020".
Doug Proper: The frets are immaterial — they're coming out. Just measure from the board. Whatever you put in is new and hopefully tall. So you've got about .030" of material to remove to get perfectly level. You shouldn't really need much fall-away on an archtop. About .030" of removal at that end on a roughly 3/16" board is not asking too much. That's the approach I'd take: pull the frets, plane the board, do a good compression refret, watch the truss rod, and leave just a couple thousandths of fall-away beyond the tenth fret — the old Frank Ford thing of moving your fall-away from the 12th–14th fret closer to the 10th–12th. On most archtops you should be able to get away without any fall-away at all, but since this one's showing symptoms of a neck shift forward, that's my supposition — the neck is pitching forward from the back becoming flatter.
35:35 — Ian: Are you thinking about just the extension, or refretting the whole board?
Corey: I was thinking about that — he's open to any of it. It'd probably be easier to just do all of it.
Doug Proper: I'm a big believer in "in for a penny, in for a pound." If you're bothering to remove material off the extension, give yourself the opportunity to give him a perfectly level playing surface — just forsake the rest of the frets. It's not a cheap guitar; it's worth doing the work. If somebody brought in a $300 Washburn or a $200 Cort archtop, that's a different conversation — then it's a matter of what kind of lighter fluid you're going to use.
37:05 — James Roadman: One more for the pipe: pulling the fingerboard and planing the riser down, if you wanted to preserve the fingerboard. Sometimes those boards aren't particularly challenging to pull — you're in it for finish work then, but if he's up for anything, that's part of the anything.
37:48 — Doug: With an '80s Epiphone — Korean or Japanese — that's important. I don't know that it rises to the value of warranting all the finish work involved in pulling a fingerboard. That's exploratory surgery to a degree.
Corey: I think it was made in Kalamazoo, actually — let me double-check. Yeah, Kalamazoo-made.
38:47 — Corey: I'll probably give it a try with my original refret plan and see how it goes.
Doug Proper: That's probably the best path forward.
39:12 — Q6. 1960s Gibson LG-0 belly: flattening without TJ Thompson's system
Patrick: I've got a '66 or '67 Gibson LG-0 with a pretty good belly. The bridge plate has been removed and the bridge is off. I'm trying to flatten it, but the TJ Thompson system doesn't go up to that year, so it won't work. What method can I use? It's got a pretty good ledge on it.
Ian: Do you have a picture of the belly?
42:11 — Ian: It looks like it's cracked right across the bridge pins.
Patrick: It does have a crack right in the middle between the two center strings. There's breakout from the remnants of what was left over from the bridge plate.
43:03 — Ian: Have you pulled the bridge plate?
Patrick: Yeah, the bridge plate is off.
Ian: Have you tried damp paper towels and just pressing the top flat?
Patrick: I haven't. I was going to put a couple of pieces of plywood in there with some beanbags sandwiched between a couple of plates — also some thick plexiglass cauls to hold things flat.
44:50 — Doug Proper: If you use plexiglass cauls when you do what Ian was talking about — damp paper towels, saturating the area to clamp it flat — use sizable cauls, something a lot wider than that. I'd like something three or four inches wide by six inches, so you're flattening the area and forcing the whole top flatter, as opposed to just flat in that one spot. The benefit of plexi is that it traps the moisture underneath so it has a better chance to do its trick, rather than plywood, which just soaks up whatever moisture's there.
45:49 — John: Can I make a suggestion? I use cauls made out of aluminum. I make up whatever I need — under the bridge plate it goes through the pin holes, and on top of the guitar it sits like that. Part of the problem with those ridges is it's not a local bulge — the whole thing has rotated. This way I can steam the inside of the guitar a bit and put gentle heat, like a heat lamp, on the aluminum, which transmits a little heat. Too hot and you damage the finish. You gradually, over some hours, push it down so the whole thing's flat, then let it cool and dry for two days. I've had to do this with a bunch of 12-strings, and it's remarkably effective. The aluminum is because the heat seems to help.
46:58 — John: Thanks, guys.
47:12 — Doug Proper: Get that top flat however you want, and then get a nice bridge plate in there that's going to resist those forces. I wouldn't be afraid of putting a robust bridge plate in — about a half-inch larger than the footprint of the bridge. Reinforcement is the entire game in keeping it flat going forward. Part of the problem with that guitar's design — beyond the plastic bridge screwed to the face — is that the bridge pins are right at the back end of the reverse-belly bridge, which was probably close to where the bridge plate ended. So all those forces lined up at the bridge and the plate, letting the whole thing tilt back and forth. That's a stupid design.
49:06 — Ian: What was the original bridge plate — plywood or spruce?
Patrick: I don't remember.
49:12 — John: When I do the 12-strings, I use maple and oversize it, and I'm careful to taper the edges — so I can make it bigger but it tapers at the edge rather than having a square edge. It seems to keep a lot of the resonance even with the bigger plate.
49:49 — John: The cauls are just quarter-inch aluminum from Amazon — you can get a variety of sizes. Six inches wide seems to work given the size of bridges. There's a plate with various holes; there are standard sizes…
[The recording in this transcript ends here, mid-sentence, at the close of Q6.]