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PostPosted: Wed Jun 13, 2018 6:51 am 
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Cocobolo
Cocobolo

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First name: Chris
Last Name: Reed
City: Stowmarket
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Country: UK
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I'm building an all-mahogany tailpiece parlor and would like help on the bridge material.

Should I make the bridge from a dense wood, like rosewood or ebony, or use the same mahogany (which is pretty light) and cap it with rosewood or ebony? I guess the real question is, light or heavy?

If it helps, the guitar is 24.5 inch scale and ladder braced. I think I'd like to favour the bass rather than the treble, on the theory that the smaller box will be treble-biased, but tapping the top produces quite a bassy tone so who knows. I want it to end up with a fairly light action and be easy playing, to contrast with the recipient's current guitar, a cheap dreadnaught.

I'm currently leaning towards a mahogany bridge with a rosewood cap, but that's because I have all these to hand and am not sure I have a suitable piece of rosewood for the full bridge!

And any suggestions whether it should have feet, or full contact, would also be welcome.


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PostPosted: Wed Jun 13, 2018 11:03 am 
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Brazilian Rosewood
Brazilian Rosewood

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Chris, I am certainly not an authority on this style guitar but I did a lot of research on ladder braced guitar when I built a "Stella clone" 12 string. One of the questions was whether to use a pinned or tailpiece style bridge. I had a brief e-mail discussion with Todd Cambio of Fraulini Guitars

http://fraulini.com/

who builds traditional small bodied ladder braced guitars with both styles of bridges. I asked him what the differences were - he said he believes the pinned bridges have slightly more complex or modern sound, tail pieces were biased a bit more to the fundimental. I was able to source a 12 string tailpiece so thats the way I built mine - however it is a completely different instrument than the one you are building so you really can not extrapolate.

I'm sure that Haans will chime in, I know that he has built guitars of this style.

There is also a discussion on MIMF along similar lines - several comments about the geometry at the bridge might be important

http://www.mimf.com/phpbb/viewtopic.php?f=3&t=5528

If you are really concerned about the mass of your bridge remember that because you do not have the rotational torque you can probably make it much smaller. You can either glue it in place or make a floating bridge (depending on your geometry). One thing that I did to hedge my bet was to make my bridge big enough that I could pin it if the tailpiece didn't work out (and I put a small maple bridge plate in it which would not be necessary with a tailpiece.

And for what it is worth, I used a rosewood bridge mainly because that is what I had and it matched the rosewood fretboard and trim.

Image


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PostPosted: Wed Jun 13, 2018 12:14 pm 
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Brazilian Rosewood
Brazilian Rosewood

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I have never built any tailpiece guitars. Neil Harpe, who is quite knowledgeable about pre-war Stellas told me that the pin bridges were a little stronger sounding than the tailpiece.
Whatever you decide to do, I would be hesitant to cut "feet" into the bridge. I've seen a lot of mandolins that have had sections of the top sink from being too thin. I would start with a full contact bridge and see where that takes you. You can always cut it out later...
As far as material, another toss up. If you are going to have a floating bridge, you can try a narrower bridge first, or make both and try both.



These users thanked the author Haans for the post: jack (Tue Jun 19, 2018 8:44 am)
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PostPosted: Wed Jun 13, 2018 1:33 pm 
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Cocobolo
Cocobolo

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First name: Chris
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Thanks both. It will be a floating bridge and I'll start with capped mahogany because that's to hand. I can always keep making bridges until I'm happy!


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PostPosted: Wed Jun 13, 2018 4:17 pm 
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Brazilian Rosewood
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Chris, your question got me thinking about questions that I have had about tailpiece guitars. I added a couple of them at the MIMF thread - you might just want to see what happens over there.


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PostPosted: Wed Jun 13, 2018 5:10 pm 
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Cocobolo
Cocobolo

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i'd go with a hardwood. ebony, or rswd (or it's ilk). no point in making a bridge -whatever the type, that has low "Q" imo


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PostPosted: Thu Jun 14, 2018 7:32 am 
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Brazilian Rosewood
Brazilian Rosewood

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If "Q" is like "drop on saw table and listen to ring", I'm all for that. Never weighed any bridges, guitar or mandolin. Always used ebony on mandolins and AFB on guitars.


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PostPosted: Thu Jun 14, 2018 10:37 am 
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Brazilian Rosewood
Brazilian Rosewood

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My typical strategy is to make a test floating bridge out of something quick and cheap at hand - mahogany, cherry, oak, whatever..

Once that has settled in and is sorted out and it plays like I want with the correct string action, intonation, etc - I then make the "Real" bridge out of something else... Often somehing exotic - ebony, rosewood, jatoba, etc.

And since I have already sorted it out on the test bridge - I can generally get pretty close on the 1st try on the final bridge so it only needs minor final adjustment.


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PostPosted: Thu Jun 14, 2018 10:51 am 
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Cocobolo
Cocobolo

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Haans wrote:
If "Q" is like "drop on saw table and listen to ring", I'm all for that. Never weighed any bridges, guitar or mandolin. Always used ebony on mandolins and AFB on guitars.


yep. in reality "Q" means nothing more than a "quality". and that measure of quality is application specific. for our purposes and IMO, the primary "quality" of a bridge should be an accurate, immediate response to -and transmission of, string energy.



These users thanked the author arie for the post: Haans (Thu Jun 14, 2018 11:09 am)
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PostPosted: Thu Jun 14, 2018 5:05 pm 
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Brazilian Rosewood
Brazilian Rosewood

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All my parlors have been red spruce, matter of fact most all my guitars have been red spruce. I can't speak to mahogany topped ladder braced, but I can say that of the three bracings I used, ladder, laminated X, and regular X. Ladder was the clearest sounding of the three, and regular X, the muddiest, or boomiest of the three. My ladders were like the old Klipsh speakers with the big 12" and 4" horns. Most folks liked the boomy fare that was offered in the age of diksko, but for classical, nothing beat those Klipsh's.
Many folks found the Klipsh's too harsh for them and lots find a new spruce parlor (12") too fundamental for their taste or not boomy enough in the bass. I built some ladder braced Grand Concerts (16") with BRW backs that sounded MUCH better and still had the clarity.
I wish you luck with the mahogany topped ladder braced parlor. Don't know if you will be able to achieve your goals tonally with it, but anything beats a cheap dread-not...
I used .050, .040, .032, .022, .016 and .011 strings. Very easy playing guitar and low action with a 24.875" scale. It is currently my favorite because I can play it sitting up in my adjustable bed...


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PostPosted: Fri Jun 15, 2018 4:59 am 
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Cocobolo
Cocobolo

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First name: Chris
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Thanks to all for the helpful comments.

This is my first real guitar (I've previously made a lot of ukes and a tenor guitar which turned out well) so I'm not quite sure what I'm hoping for tonally - I'm reacting against the boom and jangle of the cheap dreadnaught which the new owner already owns and which doesn't suit her playing at all. If it sounds at all like the tenor guitar I'll be very happy.

I'm going to go with a mahogany bridge with rosewood cap to start with - although this is a small body it taps quite bassy, so a light bridge might help bring out the treble. But making a floating bridge is an easy job, so I can swap something heavier in if it seems to need that.

Will post pictures once it's done. Rather pleased with the MoTS fretboard, and that will distract attention from the slightly uneven body shape as I built it freehand!


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PostPosted: Fri Jun 15, 2018 11:59 am 
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Brazilian Rosewood
Brazilian Rosewood

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I will watch this with interest. I have built parlor sized guitars, ladder braced guitars, all mahogany guitars, guitars with pinned and floating bridges and guitars with tailpieces. I just haven't combined them as you are proposing.

What concerns me the most is the geometry you will need to put the floating bridge on a basically flat topped guitar. The forces on the top are so different between a pinned bridge and a tailpiece and there isn't a lot of guitars out there for you to copy. Good luck and keep us posted.


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PostPosted: Fri Jun 15, 2018 2:11 pm 
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Cocobolo
Cocobolo

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unfortunately, in the world of guitars, light in weight doesn't equal "more treble" and heavy doesn't equal "more bass". there's much more to it than that.



These users thanked the author arie for the post: jack (Tue Jun 19, 2018 8:49 am)
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PostPosted: Fri Jun 15, 2018 5:23 pm 
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Brazilian Rosewood
Brazilian Rosewood

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A light guitar does not mean a better or more responsive guitar either. One of my favorite sayings is that "the tone of the instrument is in the wood on the instrument, not the shavings on the floor".



These users thanked the author Haans for the post: jack (Tue Jun 19, 2018 8:49 am)
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PostPosted: Fri Jun 15, 2018 6:08 pm 
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Cocobolo
Cocobolo

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First name: Chris
Last Name: Reed
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Freeman wrote:
I will watch this with interest. I have built parlor sized guitars, ladder braced guitars, all mahogany guitars, guitars with pinned and floating bridges and guitars with tailpieces. I just haven't combined them as you are proposing.

What concerns me the most is the geometry you will need to put the floating bridge on a basically flat topped guitar. The forces on the top are so different between a pinned bridge and a tailpiece and there isn't a lot of guitars out there for you to copy. Good luck and keep us posted.


I was (vaguely) channelling the pre-war Stellas and Harmonies. So it's ladder braced with the main brace below the bridge, and a little curve to the top via curving the brace. This should give me a bridge height of around 15mm (around 5/8 in American) which seems OK.

Fitting the bridge is just a matter of shaping the base to the arch of the top, and mandolin builders have worked that out.

Nothing to copy, as you say, so I took a bunch of ideas and then made it up as I built it.


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PostPosted: Fri Jun 15, 2018 7:21 pm 
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Brazilian Rosewood
Brazilian Rosewood

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I showed you a picture of the Stella clone 12 string that I built a few years ago. There are some pencil sketch plans of one of these from the '30's - mine is based on that. Three big beefy cross braces, a popscicle and an optional bridge plate. I included it because I wasn't sure if I was going to pin the bridge and I was pretty worried about that straight down vector into the top. Yes its a larger guitar than you are building and yes its a 12 string, but that means that I'm dealing with about 250 pounds of tension to your 170. My top is 0.125, I usually use something closer to 0.100 for small X braced guitars. The bridge height is a pretty standard 3/8 with about 1/8 of saddle sticking out, the dome is 20 or 24 foot.

Image

I built that guitar at least 10 years ago, it seems to be holding up fine. It might even be over braced. If I were to extrapolate that to a single ought sized body I would probably drop the top thickness, make the braces both thinner and a little less tall and might just put a spruce patch where the bridge plate is.

It will be fun to see what you do.


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PostPosted: Tue Jun 19, 2018 10:22 am 
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Cocobolo
Cocobolo

Joined: Thu Feb 09, 2012 4:10 pm
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First name: Chris
Last Name: Reed
City: Stowmarket
State: Suffolk
Zip/Postal Code: IP14 2EX
Country: UK
Focus: Build
Status: Amateur
Here's my bracing pattern - pretty minimal! (the blocks are because I built freehand, other than using a mould, so they help keep the shape accurate [though that didn't quite work, the body is a little wonky but not too badly so]).

Attachment:
Top bracing.jpg


Mind you, the top is fairly thick (2.5mm).

I strung it up today for the first time and I'm pleased so far. I've got more sustain than I expected, but still plenty of volume.

Once I've remembered how to play guitar I'll post a video.


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PostPosted: Mon Jun 25, 2018 9:02 am 
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Brazilian Rosewood
Brazilian Rosewood

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Last Name: Cox
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So a take on a traditional Old Regal guitar pattern then.... Many old French and Austrian guitars have the diagonal ladder as well.

One thing I found with my ladder braced guitars......

It's helpful to pre-fab an extra top brace to install under the bridge (or near it) in case the top has a bit too much sink under the bridge. If you don't need it, fine.... But if you do - it's all ready...

Second is that the string break angles over the bridge are often barely minimal... Well under 10 degrees... Once again - this is to minimize top sinking under string tension...

And so along with this - they tapered the fretboards and even sometimes gave the necks a bit of extra set to further reduce the break angle and reduce top sinking...

All this ends up giving ladder braced guitars some of their characteristic sound....

But it's also why I always use an over-height test bridge.... If the top sinks a bit more (but it sounds awesome and you don't want to monkey with it) - you have a little room for everything to settle in before the strings are laying on the fretboard....


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PostPosted: Tue Jun 26, 2018 9:09 am 
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Cocobolo
Cocobolo

Joined: Thu Feb 09, 2012 4:10 pm
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First name: Chris
Last Name: Reed
City: Stowmarket
State: Suffolk
Zip/Postal Code: IP14 2EX
Country: UK
Focus: Build
Status: Amateur
This is what I ended up with:

Attachment:
Parlour guitar front (small).jpeg


Attachment:
Parlour guitar back (small).jpeg


The mahogany bridge capped with rosewood seems to work fine, so I've just stained and finished it to a uniform colour and gone with that.

I was aiming for a bridge height of 12-15 mm but ended up at 11mm - the top hasn't sunk at all. The break angle is quite shallow and so the unwound strings have tiny notches to stop them slipping sideways when picking hard. As it turns out, this lower bridge height is probably a good thing, as the guitar is loud and amazingly responsive - I'm working hard (as a non-guitarist) to control it. But its about-to-be owner is in love with it, says it exactly suits her playing style which is quite gentle.


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PostPosted: Tue Jun 26, 2018 11:28 am 
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Brazilian Rosewood
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Nice


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