Official Luthiers Forum!
http://www.luthiersforum.com/forum/

Positioning a bridge
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=33126
Page 1 of 1

Author:  cgal_1 [ Sun Aug 07, 2011 4:53 am ]
Post subject:  Positioning a bridge

I'm about to glue on a stew mac acoustic bridge.
Am I correct in this?

Measure from the inside of the nut to the centre of the 12th fret.

Copy this measurement from the centre of the 12th fret to the front edge of the centre of the saddle.

Any help greatly appreciated.

Author:  Mark Mc [ Sun Aug 07, 2011 6:14 am ]
Post subject:  Re: Positioning a bridge

Yes - the scale length is (nut-to-12th) X 2. But you need to add compensation. This varies according to the type of guitar and the string type and gauge. Is this a steel-string with fairly regular strings? If so, I use scale length + 2mm (5/64") for the high e-string and scale length + 5-6mm (13-15/64") for the low E-string.

Different people will give you slightly varying measures for this. See what other opinions pop up here. But the compensation is really important. Without it your fretted notes will be a bit sharp.

Mark

Author:  Mark Groza [ Sun Aug 07, 2011 6:48 am ]
Post subject:  Re: Positioning a bridge

I string it up like this (with a jig i made) to get in intonation and mark the bridge position from there.

Author:  cgal_1 [ Sun Aug 07, 2011 8:31 am ]
Post subject:  Re: Positioning a bridge

Since the bridge is already slotted by stew mac, does this mean that the front edge of the bridge is not necessarily going to be perpendicular to the centre of the guitar?

Do I assume that the angle of the slot will give the correct compensation?

Author:  cgal_1 [ Sun Aug 07, 2011 8:45 am ]
Post subject:  Re: Positioning a bridge

Should have said- It's an OM from the OLF plans and will use medium guage strings.

Author:  cgal_1 [ Sun Aug 07, 2011 1:56 pm ]
Post subject:  Re: Positioning a bridge

Many thanks Todd, I'll go with your suggestion.

Thanks also to all for advice.

Author:  Mark Mc [ Sun Aug 07, 2011 3:33 pm ]
Post subject:  Re: Positioning a bridge

Your goal is to end up with the saddle in the right location. The position of the leading edge of the bridge is a secondary issue (but important for the way the guitar looks!). Basically, you put the bridge wherever it needs to go in order to have the saddle in the right place. No doubt the slot is cut on a slant in the bridge. Stew-Mac have assumed how much compensation that you want (using the usual Martin specs). So happily, it should end up that the right saddle location will give you the leading edge of the bridge being pretty close to a right angle to the centre line of the top (so it looks right as well as playing right). You have some wriggle room with shaping the saddle itself to fine-tune where the inflection point of each string will be.

Author:  WudWerkr [ Thu Aug 11, 2011 9:50 am ]
Post subject:  Re: Positioning a bridge

Mark , I like your approach ! [clap] [:Y:]

Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/