Official Luthiers Forum!

Haven't been on the forum for long time due to other commitments. Hello again, everyone!
My friend asked me to make him a parlour guitar.
I'm using CRANE Lacote plans
http://lutherie-amateur.com/Forum/viewtopic.php?t=3878

I've never made a parlour before and I would appreciate some help. I have loads of questions but I'll limited then to a few here:
Is the neck angle like that of a classical guitar and if so can I follow Cumpiano's book on this?
Most of the pictures I've seen the bridge has bridge pins. I presumed that parlours were gut or nylon string. My friend wants a nylon string. He wants a moustache shape bridge. Can I use bridge pins for nylon string, how? Should I just adopt the bridge to a tie-block?

These are the 2 mayor questions.
But also, he wants a pick-up/ microphone installed inside the guitar. We are thinking of a contact mic under the bridge. Can anyone recommend a suitable piece of hardware? Budget (or lack of) is very much an issue.

Looking forward to replies.

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We are all in the gutter but some of us are looking at guitars.

"Parlor guitar" is a modern term and doesn't really have any formal meaning. It's typically used for any guitar which is small by modern standards. A hundred years ago, (virtually) all guitars were 'parlor' 'guitars.

The Lacote guitar was designed for gut strings, so yes you can generally treat it like a classical. The pin bridge was originally designed for gut strings, and it will work with them (and nylon) just fine. Tie knots in the ends of the strings, or use LaBella 'folk singer' strings, which have plastic balls on the ends.

...

How authentic to the Lacote do you want this guitar to be?

The top should be about 3.2 mm treble side, 3.4mm bass side, and flat. The back should be arched about 3mm and is a laminate of hardwood outer layer, and Spruce inner layer, both layers with grain running lengthwise, and thickness totaling about 2.2mm. Sides are about 1.5mm thick.

The Lacote used pins for the gut strings, tie a knot at the end to act like a ball end. A nice modern string to use is Aquila's "Nylgut". The bridge is about 8mm tall, not counting the saddle.

Neck angle is about 1.5 mm. The fingerboard is 4mm. Or you could set the neck angle flat and taper the fingerboard. Both were done.

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Thanks for replies.
How obvious to tie knots at the end of strings!
How thick should bridge plate be? It's not included in the plans.
I'm not looking for an authentic Lacote guitar. My friend just likes the shape. I was going to go for a 28 foot radius on the top.
I was under the impression that neck angle on classicals was opposite to that of steel strings. That is, the angle tapers up from the soundboard. Am I wrong?

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We are all in the gutter but some of us are looking at guitars.

Many of the "romantic" type guitars have fingerboards that are thinner (and sometimes flush with the soundboard) than modern guitars. This will have an effect on the neck angle and in some cases may mean it will be 0 degrees. You should draw the string/ neck /soundboard/bridge planes out full scale to see how they all work together.
Many (most?) of the early guitars have scale lengths that are shorter than modern instruments. With nylon strings tuned to standard pitch they sound a bit wimpy(IMO). If you don't want to use gut or nylgut you might consider tuning the guitar higher or building the guitar with a longer scale length.

These were often 620mm, but 630mm is probably a better scale and does not sound too thin. I've used that on a Panormo and its very good.

I'd go with the flat top and use a 15' radius for the back. I'm making a Lacote now and that is what I'm doing.

Yes, the neck angle is up/forward from the plane of the top.

There usually wasn't any bridge plate but you can put in a thin strip of hardwood just large enough for the strings to pull against.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Good advice.
So Douglas, when you say the neck angle is 1.5 mm (and this is the opposite angle to steel strings) where do you measure that? Not above the saddle location obviously. 12th fret perhaps.
What is the advantage of having a flat top over a slight radius.
My scale length is 630mm

Should I just stop asking these questions until I've read the classical guitar part of Cumpiano and Natelson?

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We are all in the gutter but some of us are looking at guitars.

Reading "Making Master Guitars" by Roy Courtnall would be more informative for nylon string guitars. I find it much more effective and an easier read. However, neither book will help you much for an early Romantic guitar such as a Lacote. The books really focus on the Spanish tradition, not the continental European tradition.

The Lacote guitars, as well as the other Mirecourt makers, and the Viennese builders such as Johannes Stauffer, are all very well developed instruments and don't need any reinvention based upon Spanish or modern thinking. That would change them into something else. To my mind, a top dome would be one of those things. Besides, the top is small and doesn't require doming for structure, and a flat top is faster responding anyway.

The amount of neck angle is measured from the nut relative to a plane described by the top of the guitar. It is within the tradition of this guitar to make the neck angle in line with the top and set the relief by thinning the fingerboard.

Lacote guitars were built at the time when guitars were moving from a fingerboard flush with the top to a fingerboard which sits over the soundboard in the manner which we are now accustomed to.

Check out Scot Tremblay's Roseberry Guitars [url]http://www.roseberryguitars.com/showroom.html
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For more photos, look at the Early Romantic Guitar gallery of dated instruments. http://www.earlyromanticguitar.com/erg/gallery.htm


They were also built with either tuning machines or pegs, so you get to choose.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Joe; just two things determine the neck angle on a guitar: the height of the strings above the top at the saddle position and the action at the twelve fret. These are both critical design dimensions which need to be factored into the construction from the start. The string height at the saddle along with string tension determines the torque on the soundboard and therefore how much structure is required to resist that and the action determines the playability.

String height at the saddle ranges from ~10-12mm for classical guitars to ~12-14mm for SS guitars. The action is whatever the player wants. The rest of the deal is about fitting the woodwork together around your chosen top profile: flat, spherical dome, lower bout "dome" only, "flat rims", etc.. The upper surface of the fretboard needs to be a continuous plane (rarely flat, often with a small amount of relief, which obviously impacts the action, too) whilst it helps construction if the lower surface of the fretboard is flat as well; i.e. the top of the neck (no fretboard) and the surface of the upper bout are co-planar. If you go the coplanar route, the thing that determines the neck angle and action is the projection of a straight edge on the upper bout over the saddle position. i.e. the upper bout curvature. Many classical guitars are built without the neck and upper bout being coplanar, so there is a kink at the body join accommodated by chamfering the underside of the fretboard over the body. I would suggest you draw it out full size so you can see what sort of top geometry is needed to fit your requirements. More here (more related to SS guitars).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Forget modern Classical Guitar construction if you are building on that plan. Lacote comes from a N.European tradition, which is founded partly in Violin making, hence the lining, block types and the Neck joint.
You will need a Neck angle, it is around 1.5 mm's positive. Always best to check on the Guitar that you are constructing i.e. during Neck fitting. It's a plug in Neck anyway. Actually it's the tapered mortice Neck, the same joint as found on a Violin. I refer to it as the shoulderless dovetail joint. Even though it's a very shallow mortice it still has two facets, the taper along the length of the heel and the taper that points down the fretboard. If you are uncomfortable with that then you can use the dovetail joint found on SS or even a bolt on if you want.
Put in a thin veneer under the bridge position. It does save the Spruce a little. I use a thin Maple veneer, near 0.4 mm's. It's never larger than the bridge footprint, there's no need for it to be any larger.
Soundboard is certainly flat. The dimensions given by Douglas are on the higher side for Lacote instruments. He never (as far as I'm aware) went below 2.5 mm's but there certainly are Lacotes that are near to 2.5 mm's, just as there are on other French Romantic guitars. Obviously there is no one single soundboard thickness for Lacotes or other Romantic Guitars. You can only give a guideline, parameters. I'd take 2.5 mm's as a starting point but an average would be closer to 3 mm's. I've never come across one or heard of one being more than 3.5 mm's.
The backs are usually laminated, domed. Usually a fancy exotic hardwood on to Spruce. Except for Maple guitars. They were not laminated but always? one piece i.e. no centre joint. Probably hard to find a piece wide enough (it's certainly possible though). Compromise and do a joint. It's fine to do a solid Back, especially if using a medium density hardwood. Technically speaking you would laminate on all wood types other than Maple but it's only really a factor if you are going for a true copy.
The Backs on these are extremely stiff and rigid compared to most modern Classicals. the combination of the size, the bars and the lamination sees to that. Laminating certainly changes the rigidity, which you can readily feel after it's thicknessed but before the bars are glued on.
Bridges are fairly thin but are stepped or sloped in construction, the slot for the saddle being higher than the rest of the bridge. Near 7 mm at the highest point but I'll have to check my notes to be certain. I'm working off memory, which is not what it once was and I make far too many models to keep all the figures in the ailing brain. The fretboards that I've come across have all been thin - 4, 4.5 mm's, slightly cambered.
The neck to head joint is a very pointy 'V' joint, not a through joint used by someone like romanillos. The technical name for it is the Fussen joint, after the area where all the historical Lute makers came from. It's very elegant but not the easiest to do well. You can simplify it. It's hardly going to have consequences on the sound.

I've built this parlor, that name: 3/4 Size Acoustic Guitar (Similar to Martin Style 5)
This plan from LMII by Scott Antes
SC: 21.375"=543mm
Flat top Sitka Spruce, Back & Side Set Rambutan solid wood, two pieces archback with ebony stripe.
with some modified on bridge and tailpiece
here the photos:
My question: is that the guitar the same style with "the Parlor"
thanks

Herry, it's not the same and not relevant to my thread.

Thanks for those who took the time to give me advise.
I drew everything out in AutoCAD. I don't know how to put the drawing on the web so sorry I can't share.
So I've got a flat top, neck co-planer with the top.
height at Saddle= 11mm.
Action at 12th fret= 4mm.
Height of fret board + frets at 12th= 5mm
height of fret board + frets at zero (or nut)= 7mm

Does this look right. The angle would be 2mm positive.
My initial reaction from my experience of making steel strings was to have the fret board taper low at nut end and high at saddle end which obviously would cause hell of a fret buzz.


Out of interest, why are parlours and classical guitars made with the angle opposite to that of steel strings?

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We are all in the gutter but some of us are looking at guitars.

You are a bit high on the saddle height. Bridge depth is near 7 / 7.5 mm's, with a saddle projection of near 3 mm's. Call it 10.5 mm's. That's probably more in keeping with Flamenco rather than Classical Guitars.
I cant the actual Neck rather than taper the fretboard, although I'll taper it if I need to make slight adjustments. It just stops the fretboard getting overly thick at the Nut end. More a visual thing. You can use whichever method suits, it's just a means to an end.
Everything else looks OK or at least in the ball park. 2 mm is probably near to being correct. I don't know for sure because it's not how I set it up. I gauge things when fitting the Neck into the mortice. I just use dummy wood blocks that represent string height at the Nut, string height at 12 th fret and final saddle height. Bing, bang, bosh.
SS have different target 'actions', it's all in the geometry of the two different types of instruments.

Thanks, Michael. If you cant the neck that means you taper the end of the fret board? Is that a case of mark with a sliding bevel and plane to fit? I was thinking of doing a bound finger board so a constant thickness FB might be easier. I think the important thing right now is that after the advise here and drawing it out (initially wrong way round) I understand WHY I'm doing it and the 1.5mm positive neck angle is no longer an arbitrary number.
I can see that your wood blocks is a good method. I presume you bring them all into line with a straight edge?

I'm at the point now when I'm going to glue the braces to soundboard. Following the CRANE plans I'm doing ladder bracing. The braces look rather beefy at the ends. The questions are should I tuck them into the kerked lining or leave them slightly short? And, should I follow the plans and leave the brace ends beefy?
Ladder bracing is new to me as are many aspects of this project- good learning experience and lots of fun.

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We are all in the gutter but some of us are looking at guitars.

Yes, a straightedge.
I just mark the 12 th fret position on the underside of the f.board. I then start planing at the soundhole end of the f,board, moving back until I reach the mark. It's like planing a ramp. I just keep testing the fit on the actual instrument. Cabinet scraper is a useful tool for this as well as a block plane. Keep the fretboard a bit thicker than finished dimensions. That way you can have more than one go at getting it to fit. Once it fits plane the top surface to dimensions.
You may have trouble fretting it over the body. The board gets pretty thin and hammering in frets can cause the board to split. That happened to me on two or three boards before I figured things had to change. I now cut a slightly wider slot and hammer/glue them in. They hammer or rather tap in very easily. They need to be clamped.
Lacote used solid linings but not very wide, around 3 mm's. Kerfed will be OK. The bars are let in to the linings, all of them - Back and soundboard, including the diagonal one.