Guitartec Repair

09/12/2026

We have more Acoustic Expander Pickups on the way. A few are already spoken for. UPDATE.... we're down to 3 left. Come and try one out.

Easily installed in any acoustic guitar with a normal size sound hole and normal body depth, the Acoustic Expander pickup gives you adjustable Reverb, Delay and Chorus that comes directly out of the sound hole. THESE ARE TRULY AMAZING AND ARE NOT A GIMMICK. Much like a capo, it makes you play differently and go in new directions. Not only is an amp not needed, it defeats the whole purpose of this wonderful device. The whole point is you can now play your acoustic anywhere and have full reverb, delay and chorus. There is also a second version that is installed permanently into your guitar, but it has Bluetooth so you can play along with your phone's song list! You gotta check these out. It'll knock your sock off!

09/01/2026

(This writing is under construction)

All About.... M A C H I N E H E A D S (rev 2.0, 9/04/26)
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Also know as... GUITAR / BASS TUNERS, GEARS, PEGS, KEYS, ETC. EVERYTHING YOU NEVER WANTED TO KNOW ABOUT GUITAR TUNERS WILL BE WRITTEN HERE.

For this writing, I will keep to calling them "MACHINE HEADS" unless I'm trying to make a specific point.

THIS IS AN ON-GOING WRITING WITH CORRECTIONS AS I WANT TO MAKE IT AS COMPREHENSIVE AS POSSIBLE. MANY PICS WILL BE COMING TOO.

Most machine heads consist of:
- a k**b,
- a worm gear,
- a crown / spur gear,
- the string post
- a post screw
- if tension-adjustable, a nylon & metal compression washers
- the main die-cast body or a plate.
- the mounting screws or a torque screw
- Locking machine heads also have some type of screw-down lock and a locking pin

Most of the more complex machine heads also have a k**b tension screw, a few washers, either a press-fit or screw-down headstock bushing and mounting screws and/or torque screw or torque pins (to keep the body from twisting under string load. Locking tuners usually have either a rear thumb screw to lock down the string in the post or a top post lock-down screw. Some bass tuners have a crown gear tensioner.

ARGUABLY, THERE ARE 6 MAIN TYPES OF GUITAR /BASS MACHINE HEAD:

1. OPEN-BACK (pics 1-6)- These are very basic tuners where you can physically see the worm and crown gear. These are often found on 70s Japanese acoustics and electrics as well as on classical guitars. Comes in either individual or strip style. Some have stamped covers for a cleaner look. Some newer more expensive versions even have k**b tension adjustment. Strip Tuners are almost always found on Classical and vintage parlor guitars as well as Kay and Harmony archtop (and similar guitars from the 1820's to the 1960's. Also included our lower priced mandolins from the same period.

2. SPLIT POST Hybrid

3. HYBRID

4 DIECAST

5 LOCKING TUNERS

6. HYBRID (Planetary, High Ratio, Cutting Edge Design

TOPICS TO BE DISCUSSED LATER:

-K**B STYLE, Tulip, Butterbean, oval, Ketstone, Kidney Bean, Imperial, L5 Ergo, Butterfly, Cloche, Wing, Square, Trapezoid, Schaller M6 style, Industrial, Deco, Spade, Dome, Modern, Clover Leaf/Lolipop bass tuners, Barrel (Ned Steinberger).

K**B MATERIALS: Metal, Plastic, Wood, Celluloid,

-RATIOS (how many times must the k**b be turned by hand to get the post to turn 1 time

-ALL ABOUT BUSHINGS

-FINISHES

-BACKLASH

-APPLICATIONS

08/29/2026

How does a GUITARTEC REPAIR set-up differ from a "typical" set-up?

The best way to describe this is to say that we dial-in your guitar's set-up. This is not a generic set-up that you would get at big box store where they hand your guitar back and that's it. We go beyond this and make your guitar play as good as it possibly can for YOUR playing style.

We always ask our customers to play their guitar normally before they leave with their dialed-in guitar. This is not to judge how they play, it's so that we can see if it plays in tune in all registers for them, not just for us. Subtle adjustments are what a set-up is about, and we fine-tune those adjustments specifically for you.

We always tell our set-up customers that if the guitar's playability changes, like the string action gets high or they encounter note cancellation anywhere on the fretboard, to bring the instrument back. This is rarely the case, but guitars do react to different environments. They expand and contract according to ambient humidity levels. This is known as Shrink & Swell to those in the industry.

WHEN TO GET A SET-UP....
Over time, as your axe goes through natural shrink & swell cycles, it will no doubt need to be set-up, so if you notice any playability issues, or you just think to yourself, this guitar does not play like it used to, it is time for a Pro Set-Up! This can be up to twice a year as New England makes for very deep shrink and swell cycles. Some players even have set-ups at every string change as it's necessary if you want your axe playing awesome.

08/28/2026

FRIDAY 8/28/26... WE ARE OPEN TODAY FROM 3:30-8PM. Normally, we're not open on Fridays, but we were closed yesterday unexpectedly and want to make up for it by being open today. Tomorrow we have normal Saturday hours from 2:30 to 7:30 PM. C'mon by.... we're OPEN!!!

Send a message to learn more

08/27/2026

GUITARTEC REPAIR WILL BE CLOSED (TODAY) THURSDAY, AUGUST 27, 2026. Sorry, this could not be helped, but to make up for it, we will be open this Friday 8/28 from 3:30-8PM and our typical Saturday 8/29 from 2:30-7:30pm

We HATE not opening the shop when we're supposed to be there, but this could not be helped. Please come by Friday or Saturday is possible. Thanks and sorry for any inconvenience

Send a message to learn more

08/15/2026

GR HOODIES ARE FINALLY IN!

08/08/2026

WHAT IS A BRIDGE TRUSS? (rev 2.0)

Acoustic flattop guitars often suffer from what's known as a bellied top. Bellying occurs from years of string pull on the bridge and conversely, the top. This pull can start to tear the bridge off the guitar's top as well as severely stretch the top behind the bridge. In some cases, the stretching is so bad, it can cause internal braces to unglue and/or snap.

Besides this top bellying behind the bridge, the front "dishes" and becomes concave adding even more distortion to the top of your flattop guitar. This is bad because the top must remain flat in order to maintain the sting height (action) and intonation.

Add to this problem, a little bit of shallow neck angle and what you get is basically a bow and arrow. The strings are so high off the fretboard, the guitar is simply unplayable.

How do you fix this?

Well, about 35 years ago, a company in Roswell, New Mexico called JDL brought to market a device known as a Bridge Truss. At first, this device was sold under two different names: The JDL Bridge, Doctor, and the JDL Bridge System. There are two types, permanent and non-permanent.

The non-permanent model (the Bridge Doctor) is ineffective and has additional cost. IMO the unit must remain in the guitar permanently to truly solve any wood distortion issues, and you cannot fix a bellied top "temporarily". The permanent version is the JLD Bridge System.

SO.... what a JLD Truss is is a wooden cantilever device that hangs down underneath the bridge of an acoustic guitar via an inlaid screw through the bridge. This screw is covered with a pearl dot to hide it. With this adjustable cantilever installed, you can then adjust out any distortion in the guitar's top caused by string tension. It's an absolutely brilliant, simple, fast, inexpensive and effective device, and the side benefits are a more complex tone. It's a total win-win-win!

Here's a little more about this device. Again, it hangs down directly under the bridge inside the acoustic guitar (it does NOT touch the back in any way). Besides the inlaid screw that holds it in, the front of the truss rests against the underside of the bridge right where the saddle sits. It has an adjustable 8" wooden sound post (cut to size for each installation) installed through it which is manually tensioned against the guitar's tailblock (the strongest part of an acoustic guitar) using a large Allen head grub screw. This tensioning pushes the JLD towards the neck which counteracts the pull of the strings in the opposite direction and simultaneously pushes the bridge and top perfectly flat again- back to its original position, and holds it there permanently.

It's absolutely the right way to fix most acoustics, but "may" be considered a repair if you're talking a high-end guitar, thus possibly devaluating it. It literally fixes decades of string-pull damage within just a few minutes after installation which is astonishing.

This is one of the best fixes for an acoustic guitar known to Luther's and Techs. Oddly, many traditional Luthiers have poo poo'd the JLD for decades, claiming that it's not a real repair, however, it is a much more cost-effective repair than the neck reset or top straightening (using heat) they would do. Both of those methods still leave you with all the problems of a warped top again in just week to months in my opinion. The JLD is an absolutely permanent, inexpensive and wonderful repair that not only gives your acoustic guitar new life, but also gives it a better sound.

Traditionally, Bridge trusses have been made from wood, but recently a new plastic version has come out. I just installed two of them and both are holding up just fine. Truss me on this!

More pictures and corrections will be coming, so stay tuned

08/06/2026

The air conditioning is on full today at the shop, so come beat the heat and we'll make your axe play GREAT!

Send a message to learn more

08/04/2026

TRUSS RODS.... All ya need ta know. (this writing will be updated over time as it was written from memory- the ones I have left).

Truss rods in guitar necks are for counteracting string tension, and are found in most guitars that are designed to use steel and nickel strings.

Truss rods either have their adjustments made at the headstock, inside the sound hole or at the heel (or base) of a removable neck like a Fender. Some odd styles adjust on the side of a neck's heel or by using a special key on the heel of a vintage acoustic guitar.

Most nylon stringed guitars do not need truss rods, but some modern classicals, like Cordoba classical giuitars, do have adjustable truss rods. Many, pre-war gut string parlor guitars also do not have truss rods at all.

Martin, the oldest guitar company (1833), for over a century and a half had unadjustable trust rods, either shaped like an Ibeam, a T or a square shape rod. In 1985 Martin went to an adjustable single action compression truss rod.

So, to sum it up, there are essentially 3 types of truss rods found in guitars and basses:

1. un adjustable (or non-adjustable) rods like what you would find in the 1930s-60s "steel reinforced neck" Kay or harmony guitars,

2. a single-action compression truss rod, like what you'd find in a Gibson, Martin or older Fender acoustic or electric guItar. This rod either relaxes or compresses the wood at each end of the neck thus forcing the neck to bend.

3. and the much newer, dual action or 2-way self-contained rod that you find in modern guitars, including many high quality and less expensive Asian-made guitars. This rod does not compress any wood in order to function. It does, however, exert force in either a forward or back bow shape inside the guitar's neck.

Unlike a typical compression rods, a 2-way rod does not compress the wood at each end of the neck in order to make its adjustment. It is completely self-contained and literally just sits in the neck's channel. The neck has no other option than to follow the curvature of the rod that you adjust it to. It's brilliant.

Arguably, the 2-way rod is the most effective rod available and is oddly found in some of the least expensive budget guitars like Fireflys and many Ali Express and Temu guitars.

You generally won't find a 2-way rod in any vintage or re-issue style guitar. MIM Teles & Strats also do not have 2-way rods, but the American version Tele and Strat have what's called a bi-flex rod. This works in a slightly different manner than a traditional "self contained" 2-way rod where the rod expands / pushes or contracts / flexes within its capped-off channel

As for vintage style single-action compression rods, these have to be adjusted in a very careful way in order to keep them working as effective as possible. In other words, adjusting a single action rod improperly can cause it to become less and less effective over time. Many Gibsons come in to the shop with rods that do almost nothing. Most of these guitars still play OK, but fine-tuning their adjustment requires another kind of knowledge and skill.

At our shop, when we see an ineffective compression rod that simply won't adjust the neck properly, there are a few ways to approach this: sometimes lubricating the adjuster nut and inserting additional washer to help compress the wood helps. You could also consider replacing the truss rod, which in most cases is very invasive and expensive to do. EXCEPTION: Rickenbackers allow you to push (hammer) out the rod(s) and push a new one in w/o removing the fretboard.

Another fairly effective way of getting a non-functioning truss rod to adjust is by "preloading" the neck with the hopes of getting it to cooperate.

Pictured below is our neck pre-loading jig. The way it works is... With no sting tension, we loosen the truss rod all the way, then mount and adjust the jig slowly to manually cause a severe back (or forward) bow in the neck. Then, while being held in this sever bow, you then tighten the rod as much as safely possible. You then remove the jig with the hopes that the neck holds this severely bowed condition while the instrument is brought up to tuning pitch.

Once up to pitch, you now can loosen the truss rod (as opposed to tightening it) to bring the neck into correct relief. This can be tricky to do and does not work all the time, but it is the best inexpensive, most non-invasive way to get a dysfunctional neck into the proper relief. Sometimes other work is necessary to accommodate the neck in its new state of straightness.

How's your truss rod doing?

07/27/2026

THIS once-in-a-lifetime SALE BELOW IS NOW OVER, BUT CONGRATS TO EVERYONE THAT GOT THE SET-UP DEAL. MAYBE WE CAN DO IT AGAIN NEXT SUMMER IF BUSINESS ALLOWS.

SET-UP -- SALE -- SET-UP-- SALE-- SET-UP -- SALE-- 2 DAYS ONLY

GUITARTEC REPAIR SALE.... It's not often you see a sale at any guitar repair place, so here ya go....

Since Guitartec is run as an extra-efficient operation, we can sometimes make offers other repair shops can't afford to do..... SO, we are going to have a 2-DAY SUMMER SALE (on set-up work only) this Wednesday JULY 29th and Thursday the 30th....

FIXED BRIDGE GUITARS (ie. acoustic steel strings, Classicals Teles, LPs and other fixed bridge guitars (NO GUITARS WITH A TREM and/or LOCKING NUTS)
SALE PRICE- $70.00 cash + strings, parts and other work + MA tax. YES, you can still bring your own strings and correct fitting parts to help save $$$.

NON-LOCKING TREM GUITARS (Strats, guitars with Bigsbys, Vega Trems, etc) NORMALLY $125.00+ Strings, Parts, Extra Labor and taxes SALE: $99.00 cash + MA taxes. Again, you can bring your own fresh strings, parts.

LOCKING TREM GUITARS, Sale $140.00 + Strings, Parts, Extra Labor and taxes SALE: $119.00 cash + MA taxes. Again, you can bring your own fresh strings, parts.

4 & 5 STRING BASSES will be $70.00 & $80.00 respectively + strings with the same rules as fixed bridge guitars.

ACTIVE INSTRUMENTS- Use above pricing as your price guide and add $15.00. Same rules apply

REPAIRS ARE EXTRA and prices vary, but be kept as low as possible unless you specifically need certain work done.

THIS IS ALSO A THE PERFECT TIME TO CONSIDER UPGRADING YOUR GUITAR'S JACK, POTS, SWITCHES, PUPS AND TUNERS AS SET-UPS WILL RARELY BE THIS INEXPENSIVE AGAIN.

LEGAL P**P...
YOU MUST ASK FOR THE SALE PRICE PRIOR TO WORK BEING DONE!!! These are CASH sale prices, no other forms of payment can be accepted- this is how we roll to keep your costs down. This sale is two (2) days only and all guitars must be picked up by the following Saturday August 1, 2026. Customers may bring up to four (2) guitars. Any additional guitars (whether it's yours (or your friend's) will not qualify for this sale price. Guitars must be functional enough to be set up, meaning the truss rod must work and there may not be any other problems with the guitar (like frozen parts, loose frets or electrical issues) that will cause the set up to take extra time. 7 string, multi-string, Baritone, 6 string bass and any other instruments such as Banjos, Ukes and hand-made instruments are not eligible for this sale.These sale prices are only valid for JULY 29 & 30 2026. We always retain the right to refuse any instrument for this sale and for repair.