Acworth Berlin repair and build

[ADFinlayson]

I had a phone call a few weeks ago from a chap in Oxford about a custom build, he said he had an Eggle Berlin in the early 90s and he didn't like it so he had a local luthier in Kent (where he lived at the time) named Steven Acworth build him a guitar. But said it's getting a bit tatty at nearly 30 years old and wanted a new custom making, so I invited him over for a chat and got him to bring his Acworth build with him - After a bit of research, late Steven Acworth (died about 5 years ago) was a fairly well known luthier in the UK having done guitars for Status Quo, T-rex and Jeff Beck. His website is still alive with a few pics, a real internet relic: http://steve-acworth.co.uk/guitars.htm

So he brought his guitar over... By getting a bit tatty he actually meant neck snapped clean off, apparent'y this is the second time and it was reset by a luthier in Abingdon who has since retired. 

Looking at that neck pocket, it's no wonder it snapped when the guitar went over. It's a weird one, I think the route is actually on the underside which would explain this ebony filler piece on the back but can't really tell because the neck pickup cavity is covered with conductive paint.

But even with this route, it's a flat sawn neck and it's split cleanly along a grain line and not the same place as the previous break. Anyway I've glued it back together - that bit of basswood that came off with it helped it to go back together like a jigsaw. left it clamped for 36 hours then left it flat in the case without strings for another couple of days, then last night  I strung it back up.

Hopefully when I go and look at it later, it will still be in one piece. This is my first experience with Kahler trems, I must have tuned it up 15 times before it stayed in tune!

You can probably tell from the above pics, this gentleman has some specific tastes. So he gave me a list for his build.

1. Same shape as above
2. Quartersawn neckthrough to help mitigate further woes 
3. Hates figured wood, must be plain and fairly pale woods
4. doesn't like lacquer finishes so oil finish "if at all" 
5. Must have a kahler trem
6. steel girders for frets
7. Want's more available sounds so 5-way blade + push pull volume, no tone

So after a bit of hunting I ordered a neckthrough blank from Hades Roasted Maple in Canada, who also had to do some hunting - he said a perfectly quarter sawn and completely plain piece of maple is just has hard to fine as a perfect 5A piece of maple. So that is on the way with a couple of other roasted goodies for me. And we agreed on swamp ash wings. I'm hoping with all that I can keep it fairly light-weight and minimal on finish - I have read in a few places that roasted maple does not require finishing, I can't help but think it's not a bad idea to give the neck a few coats of oil, I'm sure even dry roasted maple would be able to take on water. 
 

[Charlie H 72]

Love these specs. What a weird axe! Looking forward to seeing you carry it out

[JGTay]

Nice fix.

Sounds like a good project to work on, look forward to seeing it progress. 

[ADFinlayson]

2 minutes ago, JGTay said:

Nice fix.

Sounds like a good project to work on, look forward to seeing it progress. 

Thanks man

4 minutes ago, Charlie H 72 said:

Love these specs. What a weird axe! Looking forward to seeing you carry it out

It is a weird axe. There is actually no break angle over the nut at all, there is just a locking string retainer, no headstock angle or scoop down like on a fender neck. One thing I noticed too, this guitar sounds quite dead, play it without amplification and it doesn't really resonate at all to my ears, even with brand new coated slinkys. I'm hoping the Berlin V2 would work out better. 

 

[ScottR]

I have read, that when it comes to maple necks, flatsawn is actually stronger than quartersawn.....or maybe stiffer. Not true for most woods but I've had at least one other luthier chip and and confirm this about maple.

Might be worth looking into.

SR

[mistermikev]

when I saw you post this on facebook I looked at that joint area and thought... "I think I know what the problem is"!  less real estate than an sg.  The prs is kind of like that too... it's an absolute marvel that more of them don't have issues tho... as it's a pretty vetted design.  

this should be quite the departure from prev builds for you - seemingly a shredder... and with a kahler... noice.  look fwd to seeing it come to life.

[ADFinlayson]

27 minutes ago, ScottR said:

I have read, that when it comes to maple necks, flatsawn is actually stronger than quartersawn.....or maybe stiffer. Not true for most woods but I've had at least one other luthier chip and and confirm this about maple.

Might be worth looking into.

SR

Well that's interesting, I've just done some google but can't find anything that corroborates. Not saying I don't believe you but certainly warrants more investigation. I think the main issue with this one is that the neck shaft to heel transition is so tight, goes from 19th to 21st fret so when it went over the other day it just popped clean off. I think he was thinking that the neck-through would make it unbreakable but IMO the heal needs to be a bit more substantial. Though I do wonder if quarter sawn would just make it susceptible to breaking the other way as if it fell sideways on to the headstock instead of back. Ultimately, guitars are designed to be played, not dropped. 

21 minutes ago, mistermikev said:

when I saw you post this on facebook I looked at that joint area and thought... "I think I know what the problem is"!  less real estate than an sg.  The prs is kind of like that too... it's an absolute marvel that more of them don't have issues tho... as it's a pretty vetted design.  

this should be quite the departure from prev builds for you - seemingly a shredder... and with a kahler... noice.  look fwd to seeing it come to life.

yeah that's true PRS don't have a huge amount of glue joint, but they do have a fairly chunky heel and I haven't seen one that isn't quarter sawn mahog. I haven't managed to ruin any of my prs style builds either and I do like a cheeky neck dive.

hehe yeah I know, I am not a trem guy. I did take the Kahler out and have a good look at it though, I quite like it - all encompassed within the trem itself with no back route, just enough clearance for the spring mechanism underneath it (which I need to try and find a template or plan for) and just 4 wood screws attaching it to the top. It seems like a easier entrance into into a whammy build. My only trepidation at the moment is around the locking nut and getting the cut/route for that at the right height and clean, esp on a roasted maple board. I generally don't like maple fretboards because it's way harder to hide any blunders. 

[mistermikev]

3 minutes ago, ADFinlayson said:

yeah that's true PRS don't have a huge amount of glue joint, but they do have a fairly chunky heel and I haven't seen one that isn't quarter sawn mahog. I haven't managed to ruin any of my prs style builds either and I do like a cheeky neck dive.

hehe yeah I know, I am not a trem guy. I did take the Kahler out and have a good look at it though, I quite like it - all encompassed within the trem itself with no back route, just enough clearance for the spring mechanism underneath it (which I need to try and find a template or plan for) and just 4 wood screws attaching it to the top. It seems like a easier entrance into into a whammy build. My only trepidation at the moment is around the locking nut and getting the cut/route for that at the right height and clean, esp on a roasted maple board. I generally don't like maple fretboards because it's way harder to hide any blunders. 

have had/have many a floyd... but never a kahler.  I have one in a drawer but I think I'm req by law to build a pointy guitar for it lol.  with it being a cam... my guess is it feels a lot like the trem king.  very fluid action.  def benefits from a lock nut. 

doing a lock nut- there is not much room for forgiveness.  you can always shim it... but ideally want to nail that.  Another complication is that if you do the bolt thru lock nut... it will significantly weaken the headstock transition... which makes doing a thin neck rather risky... esp if you've got a big truss rod going through right there.  both my jem and my hamer ss are like that... surprise the jem has stress cracks and the hamer was broken.  

yes, maple is a nightmare for inlay work... but I'm sure you won't have any trouble.  now michael j fox... maybe not (lol too soon?)  

[ADFinlayson]

25 minutes ago, mistermikev said:

have had/have many a floyd... but never a kahler.  I have one in a drawer but I think I'm req by law to build a pointy guitar for it lol.  with it being a cam... my guess is it feels a lot like the trem king.  very fluid action.  def benefits from a lock nut. 

doing a lock nut- there is not much room for forgiveness.  you can always shim it... but ideally want to nail that.  Another complication is that if you do the bolt thru lock nut... it will significantly weaken the headstock transition... which makes doing a thin neck rather risky... esp if you've got a big truss rod going through right there.  both my jem and my hamer ss are like that... surprise the jem has stress cracks and the hamer was broken.  

yes, maple is a nightmare for inlay work... but I'm sure you won't have any trouble.  now michael j fox... maybe not (lol too soon?)  

yeah the bolts through on the locking nut is something I am also concerned about, he has atleast said he want;s a big neck on it, I believe it's the R5 locking nut, something like 44.5mm wide, I wonder if there is anyway to avoid screwing through, I don't particularly want to go down that road if I can avoid it. Also I wonder what the value of a locking nut actually is with a premium set of locking tuners? He was talking about a zero fret and a locking string retainer like he has now but that would mean a zero fret, a nut then the string lock which would look weird to me. 

[JGTay]

The other option is to suggest a laminated neck, much stronger and you could just do it with the maple. 

[mistermikev]

1 minute ago, ADFinlayson said:

yeah the bolts through on the locking nut is something I am also concerned about, he has atleast said he want;s a big neck on it, I believe it's the R5 locking nut, something like 44.5mm wide, I wonder if there is anyway to avoid screwing through, I don't particularly want to go down that road if I can avoid it. Also I wonder what the value of a locking nut actually is with a premium set of locking tuners? He was talking about a zero fret and a locking string retainer like he has now but that would mean a zero fret, a nut then the string lock which would look weird to me. 

with a kahler... you have to have a locking nut... no locking tuners going to do it.  you could get the alternative screw down locking nut... just has wood screws instead of bolts.  all that said... if you do things to strengthen the neck I think you'll be fine.  make a vallute, do some precision drilling to ensure you don't bury the nuts too deep in the back... maybe consider a multilam neck.

w a zero fret... i don't think you'd need a nut if you have the locking nut.  haven't looked at the kahler version but the floyd keeps the strings in exact position so no need for a nut before it.

[ADFinlayson]

1 hour ago, JGTay said:

The other option is to suggest a laminated neck, much stronger and you could just do it with the maple. 

 

1 hour ago, mistermikev said:

with a kahler... you have to have a locking nut... no locking tuners going to do it.  you could get the alternative screw down locking nut... just has wood screws instead of bolts.  all that said... if you do things to strengthen the neck I think you'll be fine.  make a vallute, do some precision drilling to ensure you don't bury the nuts too deep in the back... maybe consider a multilam neck.

w a zero fret... i don't think you'd need a nut if you have the locking nut.  haven't looked at the kahler version but the floyd keeps the strings in exact position so no need for a nut before it.

Yeah we had a chat about neck construction, he's quite adamant about a one piece neck through so he can have as few glue joints as possible,  in fact it's already on route from Hades. The screw down from the top locking nut seems like the best option, I was also thinking that as his current axe has a truss rod wheel at the heel,  could do that too and keep the end of the rod away from the nut by a good 1/2 or so which should help strengthen the area. Volute is always a given for me unless someone says they really don't want it.

The floyd nut with a zero fret could work, would reduce issues if I ended up routing half a mm too low for the nut that way too, but on the other hand, doesn't a metal locking nut completely negate a zero fret (tonally)?

[mistermikev]

oh shoot moving the truss rod out of that area... that'll do it right there.  knowing that I'd do the bolts w/o worrying too much.  

zero fret... interesting thing I heard the other day about zero frets... that they wear out that fret pretty freq.  that totally turned me off on the idea.  what a pita to replace compared to a reg nut.  looked at the kahler locking nuts... they have the sm v shaped string slots so... no worries afa string movement.  might have to snag one of those pro nuts with the flip mechanism.  those are really nice.  

yes, i'd agree that there really is no point in a zero fret w a locking nut.  the only real advantage to zero nut is it makes setting height part of the leveling process, and you can change string gauges... the floyd nuts are just sort of a V shape so pretty sure you could use just about anything in there w/o issue.  I certainly wouldn't do that (zero fret)... but this just in: gtr players have all sorts of crazy ideas about that sort of thing lol.  

[Bizman62]

2 hours ago, JGTay said:

The other option is to suggest a laminated neck, much stronger and you could just do it with the maple

Exactly my thoughts. Done well with just maple and especially with no-figured woods a layman might not even notice the layers!

[curtisa]

I'd advise against using a zero fret with a lock nut, for the same reason that omitting the string retainer bar behind a locking nut makes it impossible to tune and lock the guitar without the string pitch rising.

If the strings are slightly higher as they enter the string clamps due to the zero fret being higher than the leading edge of the nut, as soon as you tighten the clamps the strings are going to kink down slightly between the zero fret and nut, and rise in pitch. Making the zero fret exactly the same height as the locking nut surface will minimise this effect, but at the expense of inviting nut/string buzz. In this situation trying to get the two components the same height would be as much work as installing the locking nut by itself.

[mistermikev]

1 hour ago, curtisa said:

I'd advise against using a zero fret with a lock nut, for the same reason that omitting the string retainer bar behind a locking nut makes it impossible to tune and lock the guitar without the string pitch rising.

If the strings are slightly higher as they enter the string clamps due to the zero fret being higher than the leading edge of the nut, as soon as you tighten the clamps the strings are going to kink down slightly between the zero fret and nut, and rise in pitch. Making the zero fret exactly the same height as the locking nut surface will minimise this effect, but at the expense of inviting nut/string buzz. In this situation trying to get the two components the same height would be as much work as installing the locking nut by itself.

is a good point... that if anything it's going to be more a pita.  that said... every locking nut guitar I've ever owned suffered this to some degree.  my jem, my hamer, a kramer I owned a few years back... i always tighten the fine tuners 30% then lock the nut then drop the fine tuners back out to go back to pitch.  This suggests to me it's kind of inherent in the floyd style lock nut.  my hamer has an original floyd, my jem has low edge pro, my kramer had a more modern floyd (mid 90s).  

[nakedzen]

On 6/29/2022 at 12:37 PM, ADFinlayson said:

2. Quartersawn neckthrough to help mitigate further woes 
3. Hates figured wood
4. doesn't like lacquer finishes so oil finish "if at all" 
6. steel girders for frets

Must be my brother from another mother!

 

[komodo]

I've also got some Hades roasted on the way. I'll watch what you do first, so I don't screw mine up! 

[ADFinlayson]

13 hours ago, komodo said:

I've also got some Hades roasted on the way. I'll watch what you do first, so I don't screw mine up! 

haha, I'll do the hard work so you don't have to Jeff. I bought a few spares to play with first because I heard that roasted maple doesn't like being routed. I've got a 2" blank to try one of my standard style necks and a over-sized blank for a fender style neck, I want to have a go at a one-piece fender neck with a skunk stripe.

I was going to record some playing on the Berlin after it went back together but I forgot, My playing is awful with a trem anyway. It's been string back up well over a week and holds it's tuning even with some diving which I was surprised by, plays very nicely too once I lowered the action quite a bit. Intonates well and sustain is fairly good, but I did notice that even with brand new coated strings, it just sounds a bit dull, so I'm hoping the V2 will be an improvement.

Anyway he's been and collected and very happy, apparently it's as it was before. I'll give this neck blank a couple of weeks before I do anything with it, need to make a couple of body templates and finish another build. Then I'll rough out the neck profile and leave it for another couple of weeks.
 

[komodo]

Very nice.  Roasted not liking routing is new to me, that's a bit of a head scratcher. The oversized piece I ordered is not in hand yet, and the design is still in flux so I'm not sure what neck(s) will be pulled from it.

I enjoyed your clients distinct tastes, esp. finish "if at all" and hating figured woods. I've realized that the guitars that really tweak my senses are all plain-ish without figured woods. I've been trying forever to design/create something that doesn't revolve around exotic woods but it always sucks me back in because I've got these wicked pieces of wood and feel some obligation to make those into guitars.

[Bizman62]

On 7/9/2022 at 5:51 PM, komodo said:

Roasted not liking routing is new to me, that's a bit of a head scratcher.

It's kin to roasted not liking screws unless pre-drilled. Roasting makes any wood a bit brittle. Further, roasting wood is a bit of a dark art. Too little and it doesn't differ from kiln dried. Too much and it's like charcoal! Hard, rot resistant - and brittle like glass!

[komodo]

I just got a roasted fret board and know what you mean. Interesting stuff. 

[ADFinlayson]

It would appear I forgot to update this one and I didn't take that many pics but here goes... I had to change my processes up a bit, I was going to use the neck template of my Suhr Modern templates for the neck taper but Andy wanted the neck to be a bit wider, so I ended up dimensioning the fretboard to measurements, glueing it on the routing the neck to match the fretboard - normally I would route the neck, glue the board on and trim the board to match the neck.

But before I could do all that, I had to do the route for the neck pickup, so I used locator pins on the board to figure out exactly where the route had to go and do the route before the fretboard was glued on. I also had to route a channel down the side of the neckthrough to where the bridge pickup cavity was going to go so that I could thread a wire through because no drill bit is going to join those two cavities up.

Then I used a surfacing bit on my 1/2" router to take 2mm off the top of the body end of the neck through except the area where the fretboard was going to go, that way the fretboard will sit 2mm higher than the rest of the body and the bridge is the right heigh relative to the strings. Then I got the board glued on.

Then the wings which were just roughed out, apparently after fretting. you can see all the router marks where I skimmed 2mm off the top of the neckthrough part

Then I finalised the body shape, mostly with the bobin sander

Then I got on to the rest of the routes - The Kahler bridge came with a cardboard template for the internal route which I duped on to the mdf, but for the outline, I screw the bridge on, went round it with a find pencil and chiselled out a couple of mm to recess it, like a really big inlay  There is a little grub screw on the back of the bridge which locks it off into a hardtail but that screw isn't accessible if the bridge is recessed so I used a round-nose bit to route a little spot to get an allen key in there. 

Fast forward a little while and it's done. Andy is picking it up later this week.

The wiring is quite cool but it wasn't fun to do. He wanted some quacky sounds but wanted to try series/parallel instead of coil splitting with a push pull which required a special 4DPT pot. Fortunately Andy did the research and found the pot, the only thing suitable that was available was a Warwick pot which was £50 by the time it was shipped and extremely fiddly.  Here is the pot next to a plectrum so you can see how tight it was, and ALL terminals needed something soldered to them. I had to do it in situ because all 8 pickup wires had to connect to the pot. Amazed I managed to get to the end without a massive solder burn on the back fo the guitar.

The push pull part of the pot goes out to the 3-way switch which goes back to the regular part of the pot before the output, the other item you see on the front is a stutter button from Tesi which was way easier to install that I thought it would be. 

Have to say as a non-trem person, I quite like the Kahler, it strikes me as the Betamax to Floyd roses VHS.

[ADFinlayson]

Almost forgot a pic of the headstock

[Professor Woozle]

I picked up an old Kahler flyer several years ago, at a very good price going by what they generally sell for on Ebay, and I do think the build quality is pretty good - it feels a lot more solid than a Floyd Rose. One day I will get round to fitting it to something...