Saturday, 15 November 2008

Scalloping a fingerboard

I have customers who play all styles of music and this one is most definately ROCK.

It can be such a treat having great musicians playing in the workshop, just showing me what's wrong with their guitars or trying them out after I've worked on them. I get to see them close up so I can analylize their playing style to get the set up just right for them. I love my job :-)

This customer came to the workshop interested in having his fingerboard scalloped from 12th fret up. This is something I'd only recomend having done for players with a high level of technical skill. Check this guy out on YouTube he's got a very accurate right hand and a light, precise touch with his left. After seeing him play I had no hesitation in agreeing to do the job.

The idea behind scalloping is to remove wood from between the frets.

This means that the player's finger tips don't touch the wood at all making vibrato and string bending a lot smoother. Right hand tapping techniques are easier too - with a right hand tap and pull off its the pull off part that can often be weak. With a scalloped board the finger can get under the string more and 'pluck' the string more easily

It all sounds great but there can be problems if the player squeezes too tightly with the left hand - this can bend notes very sharp and sound terrible especially with chords

So I always ask a few questions and watch the customer play before doing this job. If they don't like it there's no turning back.

I've seen a lot of boards (and frets) ruined by enthusiastic amateurs attacking the guitar with a file to try and scallop it. I do the bulk of the job with a router and the neck held firmly in a jig. I want the finished job to look neat and even, not like there's been an accident.

I leave a gap either side of the fret which makes no difference to the feel for the player but makes re-fretting easier.

Without this gap when the frets are pulled out huge chunks of fingerboard wood can come out too. This way the frets have more support and the board stays in good condition.

I clamp the neck in a special jig I have made specifically for scalloping. It holds the neck firmly and has a movable fence to guide the router. This way I can cut the scallops evenly and at the same depth as well as following the profile of the fingerboard. I use a rounded cutter in the router to give a nice smooth curve to each scallop. This is a pretty time consuming job and requires a great deal of accuracy.

The router is a great tool and does a very neat and consistant job but needs to be treated with respect. When I used to teach guitar making at The City of Leeds College of Music i used to say to my students 'no-one ever had a minor accident with a router'.

This is the finish I get with the router. The shape is there but its a bit rough. I finish it off with a cabinet scraper and with fine sandpaper.

After this I give the guitar a light fret stone just to make sure everything is even so i can set it up with a low action.

With the frets polished and the board oiled I'm pleased with the end result.

The player likes it too - he's brought me in two more guitars to do, another Ibanez and an Axis.

Might get some of my work shown off on You Tube soon.

I am no longer repairing guitars - since covid 19 I now work full time making pickups

Friday, 14 November 2008

Mr Glyn's new workshop

On the 1st of December 2008, Mr Glyn's Guitar Repair is moving to 19 Khyber Pass Rd (behind Bungalow Bill's guitar shop).

Hill Street Studios is expanding their recording facility into the old workshop at 10b Hill Street. They plan to build a lounge area for musicians as well as their fantastic recording studio.

For any inquiries call: 09 307 6501 or 021 912 678

Thursday, 6 November 2008

Gibson Mandolin - 1918

Well its been a busy week - I've finished a neck re-set on a 1963 Gretsch, replaced a classical bridge that had come off, refretted an Ibanez acoustic and made a bone nut and saddle for it, re-wired a Les Paul as well as numerous set ups and a few fret stones.
But the highlight was a beautiful old mandolin from 1918 its owned by by Nigel Gavin - an amazingly versatile player and an absolute legend. I keep seeing his name on credits on a huge amount of cds and not just from New Zealand.
He's best known as a guitarist and the day he brought this mandol into the workshop he also brought with him a 7-string acoustic. The guitar had been made for him by Laurie Williams and what a fantastic piece of work. Laurie's attention to detail is a joy to see and the guitar has a very light, delicate and sophisticated sound. But the reason Nigel came to see me was his mandolin.
The first string has a slight buzz when played open. As you can see from the picture there's also a piece of binding missing but he's not concerned with that and wants it left. The open string buzz implies to me that one of the nut slots has worn and is now too low causing the string to vibrate against the first fret.
For a mandolin to be playable the nut slots need to be cut lower than on a guitar. There's a lot of string tension on a mandolin and with high nut slots its going to hurt. So if I'm going to keep this nut I'm going to have to put something in the slot to give it a little more height.
The best way to do this is to use superglue and bone dust. Whenever I sand or file a bone nut or saddle I keep the bone dust for doing jobs like this. I first need to clean the slot so the glue will stick. I use specially made nut files
I'm happy to make the slot deeper because I'm going to fill it anyway. I only use 'hot stuff' super glue for this job. It comes in a few thicknesses and for this I use the thinnest. Never apply superglue directly front the container to the instrument- its hard to predict and I've seen a few nasty accidents.
I always pour the glue onto an old string packet and then use an old jewellers screwdriver to apply it. First its a thin layer of glue in the slot then a sprinkling of bone dust. The dust soaks up the glue and gets very hard. I repeat this a few times until the slot is almost filled. It dries very quickly with the dust but I still leave it half an hour or so before re-cutting the slot. Once the slot is cut to the right depth and profile I put candle wax in it to lubricate the string. It did the trick and of course can't be seen. I didn't charge Nigel for this little job. He's a guitar teacher and recomends me to his students so its only fair he gets something in return.
I just had to show you these tuning pegs - what beautifuldetail. And they still work perfectly.

I am no longer repairing guitars - since covid 19 I now work full time making pickups

Reducing hum - Screening

It is very common for electric guitars with single coil pickups to hum. Humbucking (double coil) pickups get their name from their ability to get rid of hum. A typical 'Strat' pickup will have over 7000 turns of wire on it. I've never worked out how many kms that is but I'm sure its a long way. This much wire makes a pretty good antenna. There's a lot of electromagnetic interference flying about in the air for this antenna to pick up. Electric devices such as fridges and strip lights are particularly bad for this. Not only can these man made items cause problems but so can cosmic background radiation. This is the radiation present all over the universe caused by the Big Bang - known as the shadow of the big bang. Its been around for nearly 14 billion years just waiting to get into your pickups. The way to reduce this hum to an acceptable level is to incase all of the guitar's electrics in a metal box and earth that box. That way all the interference will be cancelled out to earth before becoming a nusance.

Incidentally - this is how humbuckers do it: An electric guitar pickup is simply a magnet with a coil of wire around it. When something ferrous (a steel guitar string) is passed through the magnetic field is disturbs the magnetic flux and causes electrons in the wire to flow - this is of course electricity. But its not much electricity which is why we need to amplify it if we wanna ROCK. The signal produced is a sine wave (AC current) with peaks and troughs co-inciding to the string moving closer and further away. Imagine two pickups producing two sine waves with peaks and troughs at the same time. If we swap th ewires around on one of these pickups a peak will occur on one at the same time as a trough is on the other. These signals are out of phase and almost cancel each other out. But they also cancel any hum. This is great - no hum - but also much less sound and a funny nasal one at that. Now the clever bit is with the magnet. One coil is given a North pole and the other a South.This puts the pickups out of phase again and therefore back in phase. They are electrically 180 out and magnetically also 180 out. The result is two coils working together with almost no hum.

It this case I am screening a Kramer bass. It has one single coil pickup which the customer is not happy with. It has such a low output as to be almost unusable. He's taken it to a repairer before who recommended an outboard pre-amp to boost the signal. The pre-amp has made it louder but with the gain right up has also boosted any hum. I've decided to go to the root of the problem and re-wind the pickup as well as fit another magnet. I've suggested to him that while all the electrics are out and the pickup is in bits I also screen both the cavities and the pickup coil. This way he will have not only a better sounding and louder pickup but almost no hum. And of course he's now got a pre-amp he can sell to help pay for it.

The body had no screening at all. The pots and jack socket have a small piece of foil on the plate but its not really going to do much good as a screen. I've slackened the strings off to get the plate out but there's no need to take them off. This saves time and also string breakage.

The cavity is screened by lining it with copper foil. Several pieces need to be cut and I make sure they overlap. The idea is to make a box. The foil I use has a sticky back which is also conductive so that each touching piece connects. I don't quite trust this so I also solder each piece together.

As you can see I make sure it folds over to connect with the screen I'm going to put on the underside of the scratch plate. Although the scratch plate is bolted to the pots which are earthed I take no chances ands older an earth wire to the screen and this wire in turngets soldered to the pots.

So the completed body screening looks like this. I've kept is as neat as possible and left no gaps. Of course not all guitars are as easy to do as this one - Strats are a bit more complicated and of course its usually Fenders that I have to do this job on.Its unusual for a manufacturert o do a good screening job.

The screen on the underside of the scratch plate completesthe box. I use aluminium foil for this and cover the whole plate. The electrics are bolted directly to it so there's no need for an earth wire.

I don't cut this foil to size before sticking it on because its so much easier to do after. I use my knife as a scraper. I run it along the edge at an angle which scrapes through the foil. I then peel off the remainder and its undetectable when you screw the plate on. The same goes for the pickup hole.

So here are the finished items. They should fit together well and made a good earthed box. I often see black carbon spra on screening used in cavities on production guitars - its not a patch on doing it this way. So that's the bulk of the electrics sorted, now its on to the pickup.

Kramer have used a large single coil pickup on this guitar. Its very similar to a P90. I have already re-wound it to give it a bit more oomph. I've potted it in wax and wrapped the coil in some tape to protect it and as an insulating layer between the coil and the screen. I'll go through the winding process another time.

Its back to the copper foil. I first cut the foil to the correct width and then wrap the coil with it. It is very important not to loop it all the way around the coil. A loop of wire is an antenna which would have the opposite effect. I leave a coulpe of mm gap tom ake sure it works propperly as a screen.

Again I run an earth wire from it and to the back of the pots. A lot of care needs to be taken soldering onto the pickup. The windings are delicate and the insulation on the pickup wire
can easily melt causing a short circuit. I've just wound this one so I could wind it again - but if it was a vintage Fender...

Now its just a case of wiring in the pickup and the extra earths, tuning it, setting the pickup height, testing it all and calling the customer. I wonder if he's sold that pre-amp yet.

Here are a few more pics to show you how screening looks in a Strat:



I am no longer repairing guitars - since covid 19 I now work full time making pickups

The Workshop

I thought it was about time I gave you a lookaround my workshop.

This is the main bench where I do most of my work. I also have two other benches which I use mostly for either sawing, cutting, routing work or simply as somewhere to put instruments when they're clamped up.

This is the place in the room with the most natural light. I also use florescent lighting with a combination of tubes - daylight etc. Most of my small handtools are kept close to hand at this bench as well as oils and cleaning products underneath it.

That's a Gibson J45 on the bench - its just had a neck re-set. Panning round to the right is the computer, the all important stereo and the second workbench. There is usually a vice mounted to the corner of this bench and its where I made nuts and saddles. In the shelves I keep strings, fretwire, books, drills...

Then there's the third bench and more shelving. Under the bench are boxes of parts. Behind this bench is an area in which I plan to build a seperate room to use for dirty, dusty jobs. It will contain a bandsaw, belt sander, buffer etc. and of course dust extraction.

I have only been in this space since January 08 so its still evolving and I'm still finding new ways to use the space I have. Finally, we've come around full circle and this is the room looking across the main bench again but in the other direction. On the wall are various tools and jigs with a rack of clamps below. The shelves are covered in jars containing parts- pots, switches, saddles...

The workshop is at:
19 Khyber Pass Road, Auckland

For any inquiries or comments call on: 021 912 678

What my Customers Say

Here are some emails I have received from happy customers.
Its great to have feedback like this and so nice of people to take the time to email me:
"Hi Glyn used my Epiphone LP at practice last night and there is a HUGE improvement in tone-more clarity,more volume and lots more sustain.With the toggle switch set in the middle position I can now get really good clean tones-much closer to the Tele which our singer uses. Just going to have to re-tweak the patches on my Line 6 now to match it...Thanks S."
"Glyn how goes it? Just to say fantastic job on the Hohner jack. I want to bring in the other bass you did for me and have a new bridge put on it.Cheers A."
"Hi Glyn. I have received the strat and it sounds and feels great. Very nice. Its one of the best SRV sounding gats ive ever heard (dunno why the highway series get such a bad rep) I will send another up next week if your not too busy. Cheers P."
"Hi Glyn, I've enjoyed visiting your site a few times, I enjoy your repair blog =) Have also heard several reports of the high standard of your work, it's good to have reliable people to direct people towards when they ask. D."
"Hello Mr Glyn, I enjoyed your blog, it is fantastic to see a craftsman proud to display his talent for all to see. Thanks."
"Hi Glyn, just wanted to drop you a line to say thanks for doing such a great job on my guitar, it is like a new instrument and i didn't know how good it could sound or play, Thanks I."
"Hey Glyn, The OLP is fantastic. It's amazing how many different sounds we can get out it now, and the action is the lowest I've had on any guitar. Henceforth I shall refer to you as 'the guitar whisperer'. R."
"Hi Glyn If you think a compound radius will look better I am not going to argue with you, do it as you think it will be best,you know way more than me and I have complete trust in your work. L."
"Just a word of thanks. Very nice job on my gibson (black custom re-fret), we've been rockin almost fulltime, it sounds scary!!!!! Will bring sum more work shortly, my squire needs help (badly), might have a 50's f-hole acoustic (not a big brand but an inheritance), when I get it back from the south Is. Has done 4 gens. of parties so gets tired fast all the best, P."
"Hi Glyn, Just wanted to drop you a line to thank you for dialing in my Les Paul - it's mint, as is the SG you re-set the neck on last year. It's re-assuring to know there's a craftsman out there that really knows what he's doing. Is there anything you can do with acoustics? - I've gota 70's Takamini that's sounding a bit dull - can you give it some love? Cheers A."
"Hi Glyn, Guitar is great thanks! here's a link to our MySpace site - i'll bring you a copy of the album next time I see you. Cheers A."

Feel free to contact me about repair work (if you are in NZ). I only check emails weekly so the workshop phone is always the best 09 307 6501.

Workshop Hours

Mon……. 8-6
Tues……. 8-6
Wed…….. Closed
Thurs …..8-6
Fri ……….8-6
Sat/Sun ..Closed

Mr Glyn’s Guitars

  21a Khyber Pass Road
New Zealand
09 307 6501, 021 912678

Harmony 1930's

This is a very interesting old Harmony guitar made sometime in the 1930's.

I am certainly no expert on these guitars - its not often I get guitars in of this age to look at.

There are no markings on it anywhere to indicate a model but I'm sure there's someone out there who can help with that.

She belongs to a well known Kiwi songwriter and performer and I'm pleased to say she gets gigged regularly. So many vintage guitars never get played and I feel its a real shame - they're not ornaments! He's brought me the guitar for me to check the electrics out before it goes on a US tour with him. There's no actual fault with it but its prudent to get it checked in case any wires are just hanging on by a thread. Equipement failiure on stage is rather embarasing.

It has two pickup systems fitted. The bridge is wooden and has a piezo pickup built into it. This is great at picking up the higher frequency more percussive aspects of the tone but as it's only really 'hearing' vibration from the strings doesn't give the full picture.

The under saddle pickup is run through a Barlolini preamp which has a fixed eq setting. Its a great little system and it warms up the otherwise harsh piezo sound nicely. All the wires going to it are sound and have heat shrink over the connections which helps prevent bad connections.

Undersaddle pickups have a sound which tends to be all top and bottom. They have a jangly sparkle at the top end and preamps give thay a boomy rich bass but they can lack mids. So this guitar has a magnetic pickup fitted accross the soundhole. This gives a good midrange sound although can sound too much like an electric guitar at times. The guitar is fitted with a blend control so you can decide how much of each pickup system you want, and a volume control. The volume and tone are the most likely places for bad connections.

I took both the potentiometers out and removed all the connections, cut and stripped back the wire and re-soldered them all. I applied heat shrink to all the connections as well. Its important to tin the wires before connecting them.

This is simply applying solder to the bare wire which insures a thorough and deep solder joint. If the wires aren't tinned first it is more likely that there'll be a 'dry joint'. This is simply a joint that although looking ok is not connected properly. Dry joints are harder to track down than broken joints which is why I'm replacing all the soldering on this guitar to make sure its all sound. Since starting this blog I've heard the U.S. tour went well and they're touring Europe now. I'm still here though.


Guild D40 bridge saddle

This is a beautiful Guild D40 from 1977.

The customer is a pro player and bought the guitar new in Sydney. It hasn't been played a huge amount and its in great condition.

The problem is with the intonation - its not out a huge amount but enough to annoy the player who has a very sensitive ear.

So we decided the best solution was to fit a compensated bridge saddle. I also suggested a compensated nut but he doesn't like the look of them.

String compensation and tuning can be a complicated and frustrating subject so I'll save the details for another time and just give a simplified version. All guitars (especially steel strung) need at least a little bridge compensation to play in tune. The reason for this is in the playing action. To play a note (other than open) you need to press the string down onto the fret. Lets say the string is 2mm from the top of the fret - you bend the string (sharp) by a distance of that 2mm before you sound the note. Try fretting a note then bending the string by 2mm - you can hear it. So to compensate for this the string length is made slightly longer by moving the saddle back thus putting the note in tune again. Its made slightly more tricky by the fact that bending a thicker string by the 2mm will sharpen it more than a thinner string - so thicker strings need to be compensated more. Also wound strings react differently to plain ones. So if you change your action, string gauge or tuning you'll need to change your intonation. Another thing worth remembering is its all just compromise, you cannot play exactly in tune - there is no exact - with the limitations of action and equal tempered tuning you can get pretty close but never exactly in tune in all keys. I'll go on about this more another time because its a bit of a pet subject of mine - but anyway, back to the Guild.

The original saddle is straight and made of bone. It is a little too low to be used again so I'm going to make a new bone saddle. Bone is the best material for saddles, I get mine from usually, its at the right price, he nearly always has stock and it arrives the next day. Bone is certainly not the easiest material to work with, it's very hard and the dust isn't too pleasant. I always wear a mask when working with it. This is partly because the fine dust can be harmful and partly because it is exactly the same smell as when the dentist is drilling your teeth. Not something I want to be reminded of.

I start off by cutting the saddle to length with a junior hack saw. I cut it close to the vice jaws to lessen the chances of the bone snapping. Bone it brittle stuff. I leave it slightly oversize so I can sand it to an exact fit later.

To sand the saddle I use a sheet of abrasive paper (about 80 grit) attached to a piece of mdf with double sided tape. The mdf has a kind of handle built in so it can be easily clamped to the work bench. With this I can get the bottom of the saddle flat and true. The bottom must be a right angle to the side for the saddle to connect properly with the bottom of the saddleslot and therefore to the guitar top. This is especially critical if there is an undersaddle piezo pickup fitted.The saddle must be a snug fit in the slot so it doesn't leanf orward under string tension. If it is too tight a fit it can get wedged in and not connect properly with the bottom of the slot. Its worth spending time on the fit of the saddle.

Once I'm happy with the way the saddle sits in the slot I can shape it for height to set the action. As I am replacing a perfectly good saddle I have one to copy. So I sand the new saddle to be about 1/2mm higher than the old one. Then its a case of filing the top of it to achieve the compensated intonation. The 6th string (bass E) is set to the back of the saddle (maximum string length) and the G string to the front with the D and A set in between creating a smooth line on the top of the saddle.The B is set back and the 1st string forward.

Once the filing is finished I sand any scratches out of the bone with 800 wet'n'dry and then 1200 after which I polish it up with some burnishing compound. I love polished bone, it brings out the warm colour of it. The player uses D'Addario 12's which are great strings. I get a lot of my strings from they do a really good range at an amazing price. The delivery is cheap and next day. It means I don't need to leave the workshop to get them too. The last thing is to tune her up and check the intonation. Its a lot better than it was according to the Peterson tuner and to my ears. The customer was very happy with it though I still think it needed a compensated nut as well - ha ha